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Sonntag, 2. März 2014 - 23:00 Uhr

Astronomie - Mars-Meteorit Strukturen: Optimismus für Außerirdisches Leben?

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1.03.2014

This scanning electron microscope image shows speroidal features embedded in a layer of iddingsite, a mineral formed by action of water, in a meteorite that came from Mars.

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A meteorite from Mars has been studied up-close and scientists have detected tiny structures that could be interpreted as having a biological origin.

This moment of déjà vu is brought to you by a new paper published in the February issue of Astrobiology where a team of scientists from NASA’s Johnson Space Center in Houston, Texas, and the Jet Propulsion Laboratory in Pasadena, Calif., describe the results of work on a 14 kilogram (30 pound) meteorite called Yamato 000593 (Y000593). The meteorite sample contains strong evidence that Mars used to be a lot wetter than it is now, but the researchers also report on the discovery of evidence for “biological processes” that occurred on the Red Planet hundreds of millions of years ago.

Although this sounds exciting, there will likely be some skepticism, but the researchers appear to have foreseen the media circus that “Mars life” always inspires and refused to appear overly excited of some pretty fascinating evidence for ancient microbial life.

In 1996, President Clinton made a high profile announcement on national television that evidence for life had been discovered by NASA scientists inside another Martian meteorite called Allan Hills 84001 (ALH84001). The discovery focused around scanning electron microscope images of the microscopic detail of ALH84001. The team, led by David McKay of Johnson Space Center, identified “biogenic structures” inside the meteorite that was theorized to be formed by indigenous life on Mars.

The controversial media storm surrounding that 1996 announcement stirred a backlash that threw McKay’s team’s findings into doubt. However, McKay’s team defended the work after ruling out terrestrial contamination and other factors that may have created the nanometer-sized worm-like structures. McKay also worked on the Y000593 study until his death in February 2013.

This new work focuses around a meteorite that was discovered in the Yamato Glacier, Antarctica, by a Japanese Antarctic Research Expedition in 2000.

Analysis of the meteorite shows that it formed on the surface of Mars 1.3 billion years ago from a lava flow. Then, around 12 million years ago, a powerful impact event shattered the region, blasting quantities of Martian crust, containing any hypothetical lifeforms (and evidence thereof), into space. These chunks of Mars rock then traveled through interplanetary space until one of the samples, Y000593, encountered Earth and fell to the surface as a meteorite, falling on Antarctica some 50,000 years ago.

There are many known samples of Mars crust that have fallen to Earth as meteorites and are considered incredibly valuable scientific specimens that can be used as time capsules into Mars’ geologic past. These meteorites are nature’s ‘sample return missions,’ no spaceship required.

“While robotic missions to Mars continue to shed light on the planet’s history, the only samples from Mars available for study on Earth are Martian meteorites,” said lead author Lauren White, of NASA’s Jet Propulsion Laboratory, in a news release. “On Earth, we can utilize multiple analytical techniques to take a more in-depth look into meteorites and shed light on the history of Mars. These samples offer clues to the past habitability of this planet. As more Martian meteorites are discovered, continued research focusing on these samples collectively will offer deeper insight into attributes which are indigenous to ancient Mars. Furthermore, as these meteorite studies are compared to present day robotic observations on Mars, the mysteries of the planet’s seemingly wetter past will be revealed.”

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This scanning electron microscope image of a polished thin section of a meteorite from Mars shows tunnels and curved microtunnels.

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In their research, the scientists describe features associated with Martian clay deposits — micro-tunnels thread throughout the Y000593 sample. When compared with terrestrial samples, the Martian shapes appear to closely resemble “bio-alteration textures” in basaltic glasses. This basically means that this Mars meteorite contains microscopic features that resemble mineral formations created by bacteria on Earth.

Another factor is the discovery of nanometer to micrometer-sized spherules sandwiched between the layers of rock in the meteorite. These spherules are distinct from the minerals inside the rock and are rich in carbon, another sign that they may have been formed through biological interactions inside the rocky material.

The First Rule of “Mars Life”: Don’t Talk About “Mars Life”

Is this proof of Martian bacteria munching through Mars rock? Sadly, that’s one conclusion that cannot be made from this study and the researchers are very cautious not to write the word “life” at any point in their publication — it’s replaced by technical terms like “biogenic origins” and “biotic activity.”

“We cannot exclude the possibility that the carbon-rich regions in both sets of features may be the product of abiotic mechanisms,” the scientists write in their paper. ‘Abiotic’ means mechanisms that are not caused by microbial life, such as some chemical reaction in the rock’s geology. “However, textural and compositional similarities to features in terrestrial samples, which have been interpreted as biogenic, imply the intriguing possibility that the martian features were formed by biotic activity.”

Their caution has been applauded by other astrobiologists. “(The authors) have done well not to cry wolf and to scientifically speculate on the tubules’ origins, accepting that, as of yet, they do not know whether they are of biological origin or not,” said Louisa Preston of the U.K.’s Open University.

“This is no smoking gun,” said White. “We can never eliminate the possibility of (terrestrial) contamination in any meteorite. But these features are nonetheless interesting and show that further studies of these meteorites should continue.”

Since the 1996 ALH84001 controversy, many other researchers have come forward with meteorite studies that appear to show evidence for life on Mars and other interplanetary locations, but most have been published in sketchy journals with little to no peer review process, which serves to blur valuable research being carried out by astrobiologists. Therefore, skepticism for any Mars life study is often high.

So, until we can detect and analyze DNA of extraterrestrial origin or have the ability to return pristine samples from Mars, work like this will be filed under “fascinating but not conclusive” in the profound hunt for life beyond Earth.

Quelle: D-News

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Update: 2.03.2014

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Putative Indigenous Carbon-Bearing Alteration Features in Martian Meteorite Yamato 000593

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Abstract
We report the first observation of indigenous carbonaceous matter in the martian meteorite Yamato 000593. The
carbonaceous phases are heterogeneously distributed within secondary iddingsite alteration veins and present in
a range of morphologies including areas composed of carbon-rich spheroidal assemblages encased in multiple
layers of iddingsite. We also observed microtubular features emanating from iddingsite veins penetrating into
the host olivine comparable in shape to those interpreted to have formed by bioerosion in terrestrial basalts. Key
Words: Meteorite—Yamato 000593—Mars—Carbon. Astrobiology 14, 170–181.
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1. Introduction
The martian meteorites represent samples of the martian
regolith that were ejected from the planet as a consequence
of bolide impact events that have occurred over the
last 20 million years (Nyquist et al., 2001). Radiometric
crystallization ages determined for individual meteorites indicate
they formed across much of the martian geological
record, from as recently as 165 million years ago (Shergotty)
to as long as 4.1 billion years ago (ALH84001) (Nyquist
et al., 2001). Martian meteorites are principally mafic or ultramafic.
Nearly all those that have been studied in microscopic
detail, however, exhibit evidence of at least transient
interaction with aqueous fluids, such as the presence of secondary
mineral assemblages and evaporitic deposits present
within veins and internal fracture surfaces. Several main
mineral phases associated with these secondary alteration
features include iddingsite, carbonates, sulfates, halite, and
various clay minerals (Gooding and Wentworth, 1987;
Gooding et al., 1988, 1991; Wentworth and Gooding, 1988a,
1988b, 1990, 1991; Wentworth and McKay, 1999; Greenwood,
2000; Wentworth et al., 2001; Treiman, 2005). Other
minor phases include sulfides (Treiman et al., 1993; Wentworth
et al., 1998; Treiman, 2005), ferric oxides (Treiman
et al., 1993; Treiman, 2005) and ferrihydrite (Treiman and
Gooding, 1991; Treiman, 2005). While the exact physical
environment under which these minerals formed and the
composition of the alteration fluid are not well constrained, a
martian origin can be established based on isotopic grounds
(Imae et al., 2002) and through microstratigraphic relationships
between the secondary phases and the fusion crust (e.g.,
Wentworth and Gooding, 1990; Treiman and Goodrich,
2002). The lack of extensive alteration of primary minerals
such as olivine suggests secondary mineral formation during
evaporation of brine-like solutions (Gooding and Wentworth,
1991; Bridges and Grady, 2000; Bridges et al., 2001) at low
temperatures ( < 150C) and over relatively short periods of
time (Wentworth et al., 2005). The abundance of secondary
minerals in different meteorites ranges from *0.2 to
2 vol %, being highest in the nakhlites (e.g., Nakhla and
Lafayette) at*2 vol % (Bridges and Grady, 1999, 2000) and
in ALH84001 at *1 vol % (Mittlefehldt, 1994).
Yamato 000593 (henceforth Y000593) was discovered in
2000 at the Yamato Glacier in Antarctica by the Japanese
Antarctic Research Expedition. Based on oxygen isotope
data (Imae et al., 2002) and mineralogy (Mikouchi et al.,
2002, 2003; Imae et al., 2003a, 2003b; Misawa et al., 2003a,
2003b), it belongs to the nakhlite subgroup of the martian
meteorites. The meteorite represents a fragment of a larger
fall and has been paired with the Yamato 000749 and Yamato
000802 meteorites (Misawa et al., 2003a). Together,
these meteorites compose a whole rock mass of *15 kg
(Meyers, 2003; Misawa et al., 2003a). Mineralogically,
Y000593 is an unbrecciated igneous rock consisting mainly
of coarse-grained crystals of augite and olivine with minor
plagioclase, pyrrhotite, apatite, fayalite, tridymite, and
magnetite (Imae et al., 2003b; Mikouchi et al., 2003).
Evidence of interaction with aqueous fluids is substantiated
by carbonate phases and clay-rich iddingsite veins containing
amorphous silica-rich material, possibly a gel or opalinelike
phase, also present in the matrix (Spencer et al., 2008a,
2008b). Because iddingsite alteration veins in Y000593 are
truncated at the fusion crust, it appears likely that they
formed prior to atmospheric entry and hence have a martian
origin (Treiman and Goodrich, 2002). Additional evidence
of interaction of Y000593 with aqueous fluids includes the
presence of microtubular features or microtunnels emanating
from iddingsite veins and penetrating into the surrounding
olivine crystals. Because olivine is a reactive mineral,
exposure to aqueous fluids results in the epitactic and/or
topotactic nucleation of iddingsite within wedge-shaped etch
channels, which results in a typical lamellar structure observed
in partly altered olivine grains (Eggleton, 1984;
Smith et al., 1987). The observed microtunnels, however,
display curved, undulating shapes consistent with bioalteration
textures observed in basaltic glasses (Fisk et al.,
1998, 2006; Furnes et al., 2001; Preston et al., 2011).
Previous reports describe tunnel features and their associated
mineralogy in Nakhla. However, no investigation has
yet been reported for similar features in Y000593 and
compared to Nakhla. For the first time, we describe features
called microtunnels associated with iddingsite veins in
Y000593. Additionally, we also report the presence of indigenous
organic matter occurring as heterogeneous carbonrich
areas in iddingsite veins and carbon-bearing spheroidal
features interleaved between layers of iddingsite.
2. Methods
Optical identification of secondary phases in a 25.4mm
round polished thin section of Y000593 was performed by
using a Nikon 120 microscope equipped with a digital camera.
Series of images were taken over a range of focal distances and
combined with ImageJ1 software to give extended depth-offield
images through the depth of the section. After optical
imaging, a conductive carbon surface coating <1nm thick
was applied to the thin section to enable chemical characterization
with a JEOL 6340F field emission scanning electron
microscope (FE-SEM) equipped with an IXRF System energydispersive
X-ray spectrometer (EDS) that allows detection of
light elements including carbon. A range of acceleration
voltages and beam currents were used to determine the optimum
conditions for imaging and analysis. The optimum voltage
and current for backscatter, secondary electron, and lower
secondary imaging were determined to be 15kV at 10 lA.
Individual (point) spectra were collected by using 6.5, 10, and
15kV with an analysis spot size ranging from *0.1 to 1 lm.
A polished petrographic thin section of LEW87051, an
Antarctic achondrite recovered from the ice by a US team in
1987 (Mason, 1989), was prepared under identical conditions
to that of Y000593 to serve as a control. While the
provenance of LEW87051 is uncertain (Warren and Kallemeyn,
1990), the oxygen isotopic ratios exclude a martian
origin. This meteorite is classified as an angrite2 composed
predominantly of large magnesium-containing olivine
grains (*Fo80) embedded within a fine-grained groundmass
of euhedral laths of anorthite intergrown with clinopyroxene
and magnesium-poor olivine crystals (up to
*Fo100) (McKay et al., 1990). Its terrestrial residence time
based on 14C radiochronology is estimated to be *50
thousand years (Eugster et al., 1991), which is nearly
identical to that for Y000593 (Nishiizumi and Hillegonds,
2004). LEW87051 weighs *0.6 g (Eugster et al., 1991),
only *0.004% of that of Y000593 at *13.7 kg. The difference
in weights between the two meteorites and consequently
greater surface area to volume of LEW87051
implies effects of terrestrial contamination3 or weathering4
are likely to be more pronounced in LEW87051. While not
recovered from the same blue ice field, LEW87051 provides
a useful means to evaluate whether our observations
of Y000593 could be a product of its residence time in
Antarctica.
A chip of Y000593 (from allocated split Y000593,80)
*2mm in size was attached to a 12.7mm aluminum pin
mount with conductive carbon tape before being sputtercoated
with a thin ( < 1 nm) layer of platinum to enable
charge dissipation during FE-SEM/EDS analysis. Imaging
was performed at 15 kV, while EDS analyses were performed
at 6.5 and 10 kV; the lower kilovolt value allows for
improved detection of light elements (Z < 9).
3. Results
Optical images of the Y000593 thin section show an
extensive network of brown/orange iddingsite veins hundreds
of microns in length that cross-cut fractured olivine
crystals. Extending out approximately perpendicular from a
large fraction of the veins are iddingsite-filled tunnels typically
‡ 0.5 lm in width and tens of microns in length
(Fig. 1). In addition to the large-width ( ‡ 0.5 lm) tunnels,
approximately a third of the veins show threadlike microtunnels
of iddingsite that range from *100 to 200 nm in
width and *<1 to 4 lm in length (Figs. 1 and 2). The
majority of microtunnels display curved and/or sigmodal
(S-shaped) morphologies (Fig. 2). EDS spectra show that the
host olivine contains approximately equimolar *Si:Fe,
while the adjacent iddingsite is strongly iron-enriched with
respect to silicon (Fig. 3). A layer of silica *2 lm in width
rims a portion of the iddingsite vein (Fig. 1). EDS spectrum
of silica shows Si > Fe compared to that for both olivine and
iddingsite (Fig. 3). Two representative EDS spectra of iddingsite
show its heterogeneous nature at the submicron
scale; one contains major carbon, calcium, and manganese
consistent with the presence of mixed cation carbonate
(Fig. 3), while the other contains major carbon with little to
no calcium or manganese, indicating the carbon may be
independent of carbonate.
Y000593 chips revealed close-packed spheroidal structures
encased within and surrounded by multiple layers of
iddingsite-like compositions (Fig. 4). Structures ranged in
diameter from *100 to 500 nm and are enriched in carbon
relative to the underlying host mineral phases and surrounding
iddingsite (Fig. 4).
LEW87051 was characterized by identical techniques and
instrumentation used for Y000593. Minor rusty or oxidized
phases are present, presumably as a consequence of Antarctic
weathering, while LEW87051 showed no evidence of
iddingsite or silica alteration phases. Furthermore, there
were no observations of microtunnels extending from fractures
and veins (Fig. 5).
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FIG. 1. (A) Low-magnification scanning electron microscope/backscattered electron (SEM/BSE) view of a polished thin
section of Y000593. Expanded views of regions enclosed by green and red boxes are shown in (B) and (C), respectively.
Running diagonally across the image from top to bottom is a dark epoxy-filled vein crossing fractured crystals of olivine and
augite (gray). (B) Optical image of region enclosed by green box in (A), showing characteristic red-brown iddingsite
alteration of the silicates at the vein interface. (C) SEM/BSE view of the region enclosed by the red box in (A), the detailed
structure of the alteration edges including tunnels and microtunnels. The four circles indicate the locations that the point
EDS spectra in Fig. 3 were obtained from. The blue inset box indicates the location of the high-magnification region shown
in Fig. 2.
FIG. 3. SEM/EDS spectra of select regions shown by
green circles in Fig. 1. (A) Olivine host matrix with a significant
Fe peak indicating an intermediate composition
between fayalite and forsterite end members. (B) Silica-rich
band along the olivine fracture surface showing depletion of
Fe and enrichment of Al compared to the adjacent host
olivine. (C) Iddingsite Regions 1 and 2 illustrating the significant
heterogeneity in carbon abundance and cation variability
of the iddingsite at the micron scale. Note that the
use of epoxy-embedding medium for thin-sample preparation
makes it difficult to wholly exclude the contribution of
epoxy to observed carbon abundances; this was minimized
by acquiring spectra from alteration regions that were contiguous
at the scale of the analysis spot and showed no
observable surface fracturing or porosity.
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4. Discussion
Terrestrial iddingsite was first described in 1893 as a
mixture of hydrous non-aluminous silicates of iron, magnesia,
and soda pseudomorphous with olivine phenocrysts
having a bright orange-yellow color (Lawson, 1893). Its
composition and mineralogy has remained imprecise, since
it lacks a definite chemical composition and therefore cannot
be regarded as a simple submicroscopic intergrowth of
two or more well-characterized minerals. It is best defined
as a complex mineral assemblage5 where it can be envisioned
to represent the continuous transformation of an ironbearing
olivine crystal as it passes through various stages of
structural and chemical change in the presence of liquid
water at both elevated (300–450 K; Tomasson and Kristmannsdottir,
1972) and lower temperatures ( < 300 K) given
sufficiently long time frames (Zolensky et al., 1988). Typical
iddingsite veins show regular etching in the form of
lamellar fissures formed during the opening of fractures and
cleavage planes in olivine; these fissures display a pattern of
wedge-shaped or sawtooth borders resulting from the crystallographically
controlled dissolution of the olivine crystal
structure (Eggleton, 1984; Smith et al., 1987). Smectite
produced by weathering of olivine contains aluminum and
potassium introduced from another source.
Iddingsite in the nakhlites has long been interpreted as
pre-terrestrial (Wentworth and Gooding, 1989; Gooding
et al., 1991; Romanek et al., 1998; Treiman, 2005) and
provided the first laboratory evidence for indigenous liquid
water and a martian hydrosphere (Wentworth and Gooding,
1988a, 1989; Gooding et al., 1991; Karlsson et al., 1992;
Treiman et al., 1993; Romanek et al., 1998). Isotopic dating
suggests the iddingsite formation in Nakhla iddingsite occurred
*600 million years ago (Swindle et al., 2000), either
in a single event or through episodic aqueous exposure over
a short time interval (Swindle and Olson, 2004). Iddingsite
veins in Y000593 appear to be consistent in both composition
and mineralogy to veins in other nakhlites (Wentworth
and McKay, 1999; Treiman, 2005; Fisk et al., 2006;
McKay et al., 2006). Observations from Y000593 show
microtunnels radiating from the edges of iddingsite vein into
host olivine (Figs. 1 and 2). Unlike typical sawtooth etch
fissures in the alteration zone, undulating microtunnels
display curved and/or sigmoid-shaped threadlike morphologies
similar in size and shape to those in terrestrial silicates
interpreted as being formed by bioweathering processes
(Fisk et al., 1998, 2006; Furnes et al., 2004; Fisk and
McLoughlin, 2013). Microtunnels may have initially been
hollow but now are filled with iddingsite. It is noteworthy
that similar microtunnels emanating from iddingsite veins
have also been described within Nakhla (Gooding et al.,
1991; Fisk et al., 2006). Features are also consistent with a
recently reported library of bioerosion textures in terrestrial
basalts (Fisk and McLoughlin, 2013).
The surface of Mars has received a significant contribution
of abiotic organic matter derived from exogenous
sources (Bland and Smith, 2000) and through planetary
processes (Chang, 1993). However, current robotic in loco
parentis investigations of martian surface regolith have yet
to provide any definitive evidence for carbonaceous matter.
Nevertheless, it is worth remembering that only the Viking 1
and 2 lander missions carried molecular analysis packages
specifically designed to detect organic matter (Biemann
et al., 1976, 1977; Biemann, 1979). The failure of the Viking
landers to conclusively identify the presence of any
simple organic species in surface soils (Biemann et al.,
1976, 1977; Biemann, 1979) is now generally, although not
necessarily satisfactorily, explained as the result of UV
photocatalytic oxidation combined with an unusual and
highly oxidizing surface soil chemistry (Oro and Holzer,
1979; Zent and McKay, 1992; Yen et al., 2000). The 2012
Mars Science Laboratory Curiosity has a suite of analytical
tools associated with the Sample Analysis at Mars (SAM)
instrument, which can measure the nature of organic matter
within the near-surface of Mars. To date, the results from the
SAM analyses show that indigenous organic content on
Mars is yet to be determined (Leshin et al., 2013; Ming
et al., 2013).
In contrast, many of the martian meteorites contain detectable
organic compounds with measured abundances
typically between 10 and 200 ppm (Wright et al., 1986;
Grady et al., 1994; Romanek et al., 1994; Bada et al., 1998;
Jull et al., 2000; Sephton et al., 2002; Steele et al., 2012).
The problem is that each studied martian meteorite also
contains some terrestrial organic compounds or contaminants,
so the challenge is to discriminate the terrestrial organics
from those purported to be martian. Spatial
association (McKay et al., 2011) and isotopic analyses ( Jull
et al., 2000) have been used previously to establish a martian
heritage for some of these organics. For example, in a
recent report by McKay et al. (2011), regions of carbon-rich
matter in Nakhla were encased within iddingsite and salt
crystals and interpreted as having a martian origin. Investigations
by Jull et al. (2000) of Nakhla in which d13C
and d14C isotope analysis procedures were used discovered
that a significant amount (70–80%) of both the acid-soluble
and insoluble carbonaceous matter in this meteorite was
indigenous. Sephton et al. (2000, 2002) have subsequently
reported the presence of indigenous high-molecular-weight
organic matter in Nakhla by using solvent extraction in
combination with flash-pyrolysis gas chromatography–mass
spectrometry; they observed a suite of isotopically distinct
(d13C) aromatic and Cn-alkyl aromatic hydrocarbons.
The Y000593 iddingsite assemblage displays chemical
and mineral heterogeneity at the submicron scale (Fig. 3C;
Iddingsite Regions 1 and 2), consistent with previous
observations of martian iddingsite (e.g., Wentworth and
Gooding, 1988b, 1989; Gooding et al., 1991; Treiman,
2005). Iddingsite spectrum of Region 1 (Fig. 3C; also see
Fig. 1) shows Fe ‡ Si with minor calcium, magnesium,
manganese, and carbon, indicating the presence of abundant
iron oxides and mixed cation carbonate. By comparison, an
iddingsite spectrum of Region 2 (Fig. 3C; also see Fig. 1)
shows Si > Fe and major carbon with very minor calcium
and magnesium, indicating the presence of few iron oxides
and little, if any, carbonate. The presence of major carbon
and lack of corresponding cations is consistent with the
occurrence of organic matter embedded in iddingsite.
EDS analysis of the polished thin section of Y000593 revealed
some carbon-rich areas heterogeneously distributed
throughout the iddingsite veins. These carbon-rich areas do
not appear to be spatially associated with specific morphological
or mineralogical features.
In contrast, analysis of Y000593 chips revealed submicrometer-
sized spheroids enriched in carbon relative to
the underlying host olivine and some regions of iddingsite
(Fig. 4). Preliminary selected area electron diffraction
analysis of the underlying layer revealed only silicate
compositions; therefore, the carbon enrichment is not likely
bound to carbonate. These structures were observed embedded
in between multiple layers of iddingsite (Fig. 4); and
the spatial association of carbon-rich areas and spheroids
with the iddingsite indicates these features formed either
prior to, or contemporaneously with, the iddingsite in which
they are encapsulated. This suggests that, like the iddingsite,
they also formed on Mars. We note that indigenous organic
matter in martian samples has been arguably confirmed from
multiple meteorites by numerous independent research
groups ( Jull et al., 1999, 2000; Sephton et al., 2000, 2002),
with the most recent report in 2011 describing carbon-rich
features spatially associated with iddingsite and salt crystals
in the martian meteorite Nakhla (McKay et al., 2011).
Martian meteorites Y000593 and Nakhla have experienced
strikingly different environmental conditions after
their impact with Earth. The former was collected as a find
in Antarctica after a *50-thousand-year residence time and
the latter as a sighted fall in Egypt recovered and quickly
placed in a museum after its fall. The observation that these
two meteorites exhibit similar microtunnel features despite
the very different terrestrial landing environments and postrecovery
histories strongly argues that the microtunnels are
not the result of terrestrial contamination and instead were
formed during an aqueous alteration on Mars. For example,
while some contact with wet ground cannot be excluded for
Nakhla, its terrestrial exposure history was many orders of
magnitude less than that of Y000593. While Antarctic meteorites
undergo some terrestrial weathering, non-martian Antarctic
meteorite LEW87051 showed no evidence of iddingsite
or silica alteration phases, nor were any of the microtunnels
observed extending from fractures and veins (Fig. 5A). Again,
the presence of these microtunnels and iddingsite veins in
Y000593 (Fig. 5B) and their absence in LEW87051, coupled
with the presence of similar iddingsite veins and microtunnels
in Nakhla, is strong evidence that they were not formed
during terrestrial weathering but were formed on Mars.
This is the first report of purported indigenous carbonaceous
matter in martian meteorite Y000593. This matter is
embedded within spherules encased in layers of iddingsite
compositions and embedded within iddingsite veins presumably
formed by the action of liquid aqueous fluids on
Mars (Gooding et al., 1991). Both the spherules and microtunnel
features formed either prior to, or contemporaneously
with, iddingsite and hence have a martian origin. It
is possible the carbonaceous matter has an abiotic origin or
origins derived from exogenous (cometary/asteroidal/interplanetary
dust) sources (Flynn and McKay, 1989, 1990;
Flynn, 1993, 1996) and/or through planetary process including
magmatic and impact-generated gases (Zolotov and
Shock, 1998, 1999). Alternatively, the spherules and associated
carbonaceous matter may have biogenic origins because
spherulitic features are similar in both size (*0.1–0.5
lm) and shape to known terrestrial fossilized microbes reported
in the range of 0.13–0.55 lm (Folk and Chafetz,
2000; Brigmon et al., 2008). The presence and distribution
of carbon-rich areas with tunnel erosion patterns in iddingsite
imply this matter is relatively insoluble, consistent with
the geopolymer kerogen (Kim et al., 2006). While detailed
analyses of carbonaceous matter are outside the scope of this
paper, given abundant sample amounts, future analysis in
which techniques more destructive to the sample are used
(e.g., mass spectrometry) may provide deeper insight into
the nature of the carbon.
The Y000593 microtunnels are remarkably similar in
morphology to bioerosion textures found in terrestrial Fe-
Mg silicates described by Fisk et al. (2006), Preston et al.
(2011), and Furnes et al. (2004). The microtunnels are inconsistent
with alteration channels produced by the crystallographically
controlled abiotic dissolution of olivine
(Eggleton, 1984; Smith et al., 1987). Fisk et al. (2006)
suggested common features of biotic alteration include the
following: tunnels that emerge from a glass or mineral
surface that has been in contact with water, a host mineral or
glass replaced with hydrous minerals, dark brown to black
boundary between the glass and fracture-filling clay, uniform
tunnel size and shape in a single sample, uniform
tunnel diameter along the length of the individual tunnel,
and localized, nonuniform distribution of tunnels along
fractures or mineral edges. We suggest that the microtunnels
in Y000593 display all the aforementioned characteristics.
Previous studies of terrestrial glass and olivine samples
interpreted the presence of tunnels and microtunnels to be of
biogenic origin (Fisk et al., 1998, 2006; Furnes et al., 2004;
Preston et al., 2011). This interpretation is greatly
strengthened by the presence of DNA in some of these
terrestrial features (Fisk et al., 1998, 2006). Similar DNA
fluorescence experiments performed by Fisk et al. (2006) on
microtunnels in Nakhla did not detect DNA. As noted earlier,
however, the nakhlites appear to have been subjected to
aqueous alteration during a period as old as 600 million
years ago. Therefore, if martian DNA were introduced into
the tunnel structure of nakhlites at that time, its instability
during weathering and aging would likely preclude its survival
in present-day samples.
Previous studies reveal that a combination of SEM and
EDS can be used to differentiate between mineralized carbonate
and organic matter by analyzing composition and
texture (Toporski et al., 2000; Toporski and Steele, 2007;
McKay et al., 2011). Specifically, the composition of carbonate
requires the presence of cations (e.g., Mg, Ca, Mn, or
Fe) to balance the CO2 3 anion. Therefore, the relative
abundances of the cations can be detected by EDS and should
correlate to carbon in carbonaceous material. If no cations are
detected by EDS to correlate with carbon, one may consider
the possibility of this material existing in the organic in
phase. Furthermore, observed textures such as stringlike
membranous material, tubular features, honeycomblike
networks of material are inconsistent with typical mineralcarbonate
structures and, in correlation with compositional
observations, may indicate organic material. However, we
note that when both phases are intermixed, such as may be
the case in Y000593, differentiating between these phases is
complex. Due to the often limited sample size for meteoritic
and lunar materials, SEM and EDS are well-established
nondestructive analytical methods that are frequently utilized
to characterize extraterrestrial samples (Heiken et al., 1972;
Wentworth and McKay, 1987; Toporski et al., 2000; McKay
et al., 2011; Ross et al., 2011; Ruzicka et al., 2012).
5. Summary and Conclusions
The martian meteorite Y000593 contains two distinctive
sets of features associated with the martian-derived iddingsite.
The tunnel and microtunnel structures are typically
found in olivine along the margins of mineralogically complex
iddingsite veins. These microtunnels contain areas of
enhanced carbon abundance that, in some cases, are not associated
with common carbonate cations and therefore are
interpreted as carbonaceous material, perhaps similar to
kerogen. The second set of features consists of nanometer- to
micrometer-sized spherules sandwiched between layers of
indigenous iddingsite and distinct from carbonate and the
underlying silicate layer. Similar spherules have also been
described in Nakhla (Gibson et al., 2001). EDS spectra of the
Y000593 spherules show that they are significantly enriched
in carbon compared to the nearby surrounding iddingsite
layers. A striking observation is that these two sets of features
in Y000593, recovered from Antarctica after about
*50-thousand-year residence time, are similar to features
found in Nakhla, an observed fall collected shortly after
landing. We cannot exclude the possibility that the carbonrich
regions in both sets of features may be the product of
abiotic mechanisms; however, textural and compositional
similarities to features in terrestrial samples, which have
been interpreted as biogenic, imply the intriguing possibility
that the martian features were formed by biotic activity.
Acknowledgments
We gratefully acknowledge the allocation of Yamato
000593 by the Polar Institute of Japan. This research was
conducted at NASA Johnson Space Center while the first
author (L. White) was under contract with Jacobs Engineering
(Jacobs Engineering, ESCG, 2400 Bay Area Blvd,
Houston, TX). Part of this work was also conducted at Jet
Propulsion Laboratory, California, Institute of Technology,
under contract with National Aeronautics and Space Administration.
This manuscript is dedicated to our colleague
David S. McKay, who died on February 19, 2013. Dave’s
guidance and perception of the important features within
martian materials will long be remembered.
Quelle: ASTROBIOLOGY




3202 Views

Sonntag, 2. März 2014 - 19:59 Uhr

Raumfahrt - Airbus Defence and Space erstellt "Weltraumofen", um Werkstoffe der Zukunft auf der ISS zu testen

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Airbus Defence and Space builds ‘space furnace’ to test materials of the future on the ISS (c) NASA

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Airbus Defence and Space builds ‘space furnace’ to test materials of the future on the ISS

The Electromagnetic Levitator will be launched to the International Space Station (ISS) on ATV-5

EML Electromagentic Levitator - Dennis Mitschke is fixing the Sample chamber to the Experiment module (c) Airbus Defence and Space
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Airbus Defence and Space, world’s number two in space technologies, has built the Electromagnetic Levitator (EML) facility which was developed under parallel contracts of the European Space Agency ESA and the DLR Space Administration. EML is a containerless processing furnace for materials research in the European Columbus lab, set to uncover a deeper understanding of advanced alloy and semiconductor materials and their molten state properties for the optimisation of industrial scale casting as well as for basic research. The EML together with the first batch of samples is part of the cargo complement scheduled to be transported to the International Space Station (ISS) in June by the European resupply spacecraft ATV-5 (Automated Transfer Vehicle).
At least until 2020 the unique test facility will process various metal and semiconductor samples at temperatures of up to 2,000 degrees Celsius in a series of experiments, using the principle of electromagnetic levitation and inductive heating. Several teams of materials scientists and industrial researchers have the objective to acquire high precision data of temperature-dependent thermophysical properties of molten advanced materials, which play a key role in complex casting and solidification processes for these materials when they are used for parts manufacturing on an industrial scale. Performing levitation under microgravity conditions requires only small levitation forces, and deformation of the samples will be avoided which falsifies the measurements based on in-situ optical principles.
It is almost impossible to imagine modern life without products made from high-tech materials. They are used in industrial goods such as jet turbine blades and clean engines for cars. They include supermetals used to make electronic components and high-performance magnets, as well as medical devices such as artificial joints and prosthetics. They are even found in fine metal powders used as catalysts in chemical reactions. Understanding more about materials properties in liquid state for casting models and solidification parameters for these advanced materials is essential both for monitoring the parts’ production process and secure a high quality of the manufactured products.
To this end, a continuous series of experiments are due to be performed by the new EML facility, which will be accommodated in the European Drawer Rack in the Columbus Laboratory on the ISS. Weighing in total approximately 360 kilograms, the EML facility consists of four modules, the most important of which is the Experiment Module (EXM). The samples, which are stored in special containers made from ceramic and rhenium, are fed into the process chamber in a similar arrangement to the magazine of a revolver. This magazine contains 18 spherical metal samples for the experiments, including various aluminium, copper and nickel alloys.
For processing one sample at a time is positioned using electromagnetic levitation and then molten by inductive heating in an electromagnetic field generated by a coil system. Numerous parameters can then be measured simultaneously on the levitated metal droplet. Containerless non-contact methods will be used for all the experiments in order to avoid any interference on the measurements compared to the necessary use of a crucible on ground.
Operation of the Electromagnetic Levitator will be controlled and monitored by the German Aerospace Centre’s User Control Centre (MUSC) in Cologne. The scientists in charge of the experiments can carry out real-time, direct tracking of each and every detail of the melt cycles from this control centre thanks to a digital video observation camera, a high-speed data camera capable of capturing up to 30,000 images per second, and a pyrometer. Before flight the individual sample materials have been thoroughly characterized before on parabolic flights with the Tempus facility provided by DLR. The ISS samples can even be returned to Earth at a later point in time to enable the researchers to perform further testing.
The Electromagnetic Levitator facility was developed and built by teams of Airbus Defence and Space Space Systems as industrial prime contractor. With over 25 years of experience in this field, Friedrichshafen experts built a number of flight units as part of the Tempus project, for parabolic flights (20 second experiment duration), sounding rockets (6 minutes) and for three Spacelab missions on board the U.S. Space Shuttle (1–2 weeks’ mission duration) in the 1990s. Nowadays the ISS laboratories provide continuous access to microgravity conditions.
About Airbus Defence and Space
Airbus Defence and Space is a division of Airbus Group formed by combining the business activities of Cassidian, Astrium and Airbus Military. The new division is Europe’s number one defence and space enterprise, the second largest space business worldwide and among the top ten global defence enterprises. It employs some 40,000 employees generating revenues of approximately €14 billion per year. 
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Quelle: Airbus

2761 Views

Sonntag, 2. März 2014 - 19:43 Uhr

Astronomie - UC Irvine Astrophysiker beobachten Gammastrahlen-Photonen in der Mitte von Milchstraße

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UC Irvine researchers reveal more data from NASA’s Fermi Gamma-ray Telescope
 

UC Irvine astrophysicists report that gamma-ray photons observed from the center of the Milky Way Galaxy are consistent with the intriguing possibility of dark matter annihilation, according to research submitted to the journal Physical Review D.

Kevork Abazajian, Nicolas Canac, Shunsaku Horiuchi and Manoj Kaplinghat analyzed data from NASA’s space-borne Fermi Gamma-ray Space Telescope and found that only a narrow range of dark matter models can produce an excess of gamma rays coming from the Milky Way. These gamma rays could be produced as particles of dark matter annihilate one another. The data was collected August 2008 – May 2013. The findings were also presented today at UCLA’s the 11th Symposium on Sources and Detection of Dark Matter and Dark Energy in the Universe.

“The data provides a better-than 10 percent precise determination of the dark matter’s particle mass with the best estimates we have of what else is going on in the Galactic Center,” says Abazajian.

According to Kaplinghat, the signal is robust because its key features did not change even when several other possible sources were included. He also pointed out that a large number of yet unseen pulsars emitting gamma rays could also be an explanation for this signal.

The nature of 85 percent of the matter in the universe is an unknown material called dark matter. The leading theory is that dark matter consists of weakly interacting massive particles (WIMP’s).  When two WIMP particles meet, they annihilate each other to produce more familiar particles – including gamma rays. 

Quelle: University of California

 


2510 Views

Sonntag, 2. März 2014 - 10:16 Uhr

Raumfahrt-History - Hugh Dryden: Ein Mann und sein Vermächtnis

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A brilliant aerodynamicist and leader, Hugh Dryden may well be the most influential NASA official of whom you’ve never heard.

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A brilliant aerodynamicist who not only conducted critical aerospace research far ahead of his time, but also a quietly effective government leader, Hugh Dryden may well be the most influential NASA official of whom you’ve never heard.

Dryden was born in the rural village of Pocomoke, Maryland on November 7, 1898. After suffering various career and financial setbacks his family settled in Baltimore, where his father worked as a streetcar conductor. Despite his modest background, Dryden showed signs of superior aptitude, having achieved a fifth-grade reading level by age 8. After graduating high school first in his class at age 14, Dryden was awarded a full scholarship to study at the prestigious Johns Hopkins University. Asked later in his life what he thought made the United States a great nation, he replied “…the equality of opportunity offered to each of its citizens to develop his personal talents to the fullest and to participate in the development of those accomplishments and ideals which make our national environment beneficial to all people.” Dryden’s life embodied this perspective and aspiration.

While at Johns Hopkins, he studied under Professor Joseph Ames, the legendary physicist, founding member of the National Advisory Committee for Aeronautics (NACA) and namesake of the Ames Research Center. Ames became Dryden’s mentor and shaped his career. In three years, the young Dryden completed his bachelor’s degree, followed by his master’s degree a year later.

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T. Keith Glennan (second from right), the new NASA Administrator, and Hugh L. Dryden (left), Deputy Administrator, are sworn in August 19, 1958, as President Eisenhower looks on.
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Ames then placed Dryden in a full-time job at the National Bureau of Standards testing munition gauges as the First World War wound to a close. Despite a long commute by train each day, Dryden simultaneously worked in the Bureau’s laboratory while completing his doctoral degree at Johns Hopkins. A year later, at the age of 20, Dryden was granted a doctorate in applied physics, making him the youngest person ever to receive a Ph.D. from Johns Hopkins University. His doctoral dissertation “Air forces on circular cylinders” broke new ground on the scale effects of air flows and won him the post of Chief of the Aerodynamics Section of the National Bureaus of Standards. 

In charge of one of the country’s most advanced wind tunnels, Dryden quickly won grants from the fledgling NACA and conducted research on the problems of wind tunnel turbulence and boundary layer flow that earned him international recognition.  Working closely with his research partner and mentor, Dr. Lyman J. Briggs, Dryden produced a series of path-breaking NACA Technical Reports and other publications that dealt with supersonic flight at a time when the top speed of airplanes was just over 200 miles per hour.

Dryden’s keen mind was accompanied by a self-effacing sense of teamwork that not only won him research success, but rapid promotion to management positions at the Bureau of Standards and recognition by national and international professional societies. It also brought him to the attention of the leading scientific minds of the time, including Theodore von Kármán. Although their personalities could not be more different, von Kármán and Dryden developed a close relationship and would, together, have a huge impact on the course of U.S. science and technology policy.

During World War II Dryden led the development of the U.S. Navy’s BAT radar homing missile, which was used to great effect in the final phases of the war in the Pacific. Von Kármán then recruited Dryden to serve as his deputy on the Army Air Force’s Scientific Advisory Group. After inspecting European science facilities (dressed as an Army Colonel), including intense debriefings of German rocket scientists, Dryden served as the general editor for the seminal “Toward New Horizons” Scientific Advisory Group report to General Hap Arnold. The report set the agenda for post-war research for both military and civilian efforts in air, and space, flight.

On the retirement of long-standing leader Dr. George W. Lewis in 1947, Dryden was selected to take his place at the helm of the NACA. Building on the insights gained during the War, Dryden quietly, but effectively, overhauled the NACA to pursue high-speed flight and space research. Within a month of his appointment, he travelled across the country to visit the Muroc Flight Test Unit that had been set up as a temporary NACA deployment for the initial supersonic flights of the Bell X-1. Shortly afterward the temporary operation at Muroc became a full-fledged permanent NACA research facility (that was later named in honor of Dryden). 

Dryden’s standing as a world-class scientist, familiarity with his military and industry partners, and focused patience served the NACA and the country well during this critical period of research and development. He brokered the arrangement with the U.S. Army and U.S. Navy that led to the creation of the hypersonic X-15 and served as Chairman of the interagency committee in charge of that project. Dryden was also the key facilitator in creating the National Unitary Wind Tunnel Plan that resolved industry and military service disputes over the creation of the family of supersonic and hypersonic wind tunnels that proved crucial to U.S. success in aerospace research. He also encouraged brilliant researchers, particularly at the Langley and Ames research centers, to focus on rocketry and re-entry studies. Without changing the NACA charter, and largely on his own initiative, Dryden transformed the focus of research so that by the mid-1950s a quarter of the NACA’s research projects were focused on the topic of space travel. 

When the Soviet Union surprised the world with the first Sputnik launches in 1957, the NACA was already a de facto space agency. Dryden had hopes of continuing to lead the NACA as it was transformed into the National Aeronautics and Space Administration (NASA) in 1958. However, some senior members of Congress held Dryden responsible for the Sputnik surprise. Dr. T. Keith Glennan was appointed the first Administrator of NASA, but he accepted the post only on the condition that Dryden remain as Deputy Administrator. With characteristic humility Dryden swallowed his pride and put his all into transforming the NACA into NASA. The rapid development of Project Mercury, other human spaceflight programs, and scientific work at NASA were a testament to Dryden’s technical insight, deft hand at selecting and encouraging young leaders of promise, and selfless devotion to the mission. In the spring of 1961, Dryden also played a critical role in convincing Vice President Johnson and President Kennedy that a human mission to the Moon was a feasible goal for the 1960s.

Although diagnosed with cancer in 1962 Dryden kept up a punishing schedule of work as Deputy Administrator. In addition to overseeing the spectacular growth of NASA’s staff, facilities, budget, and assignments in the early 1960s, Dryden was also charged with leading negotiations with the Soviet Union on space cooperation. His international standing and previous encounters with Soviet scientific leaders through his membership in a wide variety of international professional societies made him the natural choice for initial contacts with the Soviets during the Eisenhower Administration. Later, under President Kennedy, Dryden brokered the very first space cooperation agreement with the USSR in 1962. He died in December 1965, several years before the Apollo Program came to fruition, and decades before his efforts at international space cooperation with Russia would bear lasting fruit. Throughout his adult life Dryden also served as a very active lay Methodist minister, spending many of his Sundays preaching at churches around the country. In March 1976, the NASA Flight Research Center at Edwards, California, was renamed the Hugh L. Dryden Flight Research Center, in his honor.

On Saturday, March 1, 2014, the Hugh L. Dryden Flight Research Center will be officially renamed Neil A. Armstrong Flight Research Center, in remembrance of the first astronaut to walk on the lunar surface in 1969, a feat achieved as a result of Dryden’s enduring legacy. Dryden’s name will, however, remain attached to this key facility; the Western Aeronautical Test Range located at the Center will be named in Dryden’s honor.

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Showing the resolve with which he took over the directorship of the NACA, Hugh L. Dryden poses in front of the motor and fan powering Langley's 19-foot pressure tunnel.

Seal of the National Advisory Committee for Aeronautics (NACA), established by Congress in 1915. The seal depicts the first flight by the Wright brothers at Kitty Hawk, North Carolina, in December 1903.
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Quelle: NASA

2642 Views

Sonntag, 2. März 2014 - 10:10 Uhr

Raumfahrt - ISS-Alltag - Abschluss von CubeSats-Einsatz und Crew 38 vor Rückkehr

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The International Space Station completed this week’s deployment of the NanoRacks CubeSats. The six-member Expedition 38 crew also worked on various science activities and prepared for a March 10 Soyuz undocking.

The final set of CubeSats, used for Earth observations, were released from the Kibo laboratory’s Multi-Purpose Experiment Platform (MPEP) Friday at 2:30 a.m. EST. Japanese flight controllers then guided the Japanese robotic arm to place the MPEP back inside Kibo’s airlock. The airlock was then repressurized wrapping up the micro-satellite deployment activities.

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Expedition 37/38 crew members (from left) Mike Hopkins, Oleg Kotov and Sergey Ryazanskiy are preparing to return to Earth inside their Soyuz TMA-10M spacecraft March 10.

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Japanese astronaut Koichi Wakata worked on an internal robotics project partnering with NASA astronaut Rick Mastracchio. The duo participated in the SPHERES-SLOSH experiment using tiny satellites to study how fluids behave inside a container in microgravity. The tiny satellites, also known as SPHERES, may provide advances for rocket fuel delivery systems.

Wakata also had time set aside Friday morning for work with the Aniso Tubule plant experiment. He retrieved experiment samples and set them up for microscopic observation.

Flight Engineer Mike Hopkins opened the Fluids Integrated Rack inside the Destiny laboratory for some maintenance work. He temporarily removed an optics bench in the rack to replace an avionics package and a white light lamp. Hopkins later joined Mastracchio for a live question and answer session with students from Osage Beach, Mo.

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Astronaut Mike Hopkins works inside the Light Microscopy Module which is part of the Destiny laboratory's Fluids Integrated Rack.

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Commander Oleg Kotov and Flight Engineer Sergey Ryazanskiy teamed up to prepack gear for their upcoming return to Earth. Hopkins will join them for the ride home on March 10, officially ending Expedition 38. In preparation for the departure Kotov on March 9 will ceremonially handover command to Wakata, who will become the first Japanese station commander.

Veteran cosmonaut Mikhail Tyurin photographed the conditions of the windows inside the Station’s Russian segment. He also monitored the reaction of jet and propulsion system exhaust on the Earth’s upper atmosphere and the space station’s external environment for the Relaxation experiment.

 

Objective:

Investigation of chemiluminescent chemical reactions and atmospheric optical phenomena occurring during high-speed interaction between jet engine exhausts and the Earth's upper atmosphere, atmospheric optical phenomena during re-entry of bodies into rarified upper atmosphere and its optical properties in the UV range.

Tasks:

Conducting radiometric and spectrometric measurements in the UV range:

  • Radiation emitted in reactions of interaction between ISS RS propulsion system exhaust products and atomic oxygen;
  • Radiation emitted in reactions of interaction of Soyuz and Progress propulsion system exhaust products during undocking maneuvers, retroburns and re-entry into the Earth's upper atmosphere;
  • Spacial distribution and emission spectra of atmospheric formations and phenomena.

Science Hardware Used:

"Fialka-MV-Kosmos multispectral UV system which includes

  • UV camera
  • Spectrometer
  • Video camera
  • A set of interference filters

Consumables:

  • Mini-DV video tapes
  • Diskettes

Expected Results:

Determining the effects of propulsion system exhausts on the Earth upper atmosphere and ISS environment, on optically sensitive surfaces (windows, equipment lenses, solar array panels). In perspective, simulation of atmospheric optical phenomena in ultra-violet, visible and near-infrared spectral bands (Earth atmosphere nightglow, SC re-entry glow, planetary atmospheric glow).

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Waiting to replace the returning astronauts are Expedition 39/40 crew members Steve Swanson, Alexander Skvortsov and Oleg Artemyev. The trio is in Star City, Russia, conducting suited dress rehearsals inside a Soyuz simulator. They are scheduled to launch aboard a Soyuz TMA-12 Soyuz spacecraft on March 25 for a six-hour ride to the station’s Poisk mini-research module for a docking.

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Quelle: NASA


Tags: Final CubeSats Deployed 

2390 Views

Samstag, 1. März 2014 - 15:30 Uhr

Raumfahrt - Vorbereitungen für Chinas Mondsonde Chang'e -5 im Jahre 2017

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BEIJING, Preparation for the 2017 launch of China's lunar probe Chang'e-5 is going as planned, the country's leading space scientist Ye Peijian told Xinhua on Saturday.

Chang'e-5, as part of China's third-phase lunar program, is expected to bring back moon rock samples to Earth, a move hailed by Ye as "a historic moment" for the country.

China's lunar program covers three stages. It completed the second phase after the Chang'e-3 probe soft-landed on the Moon on Dec. 14, with the country's first moon rover Yutu (Jade Rabbit) aboard.

But Yutu has experienced a mechanical problem that scientists are still trying to repair.

Ye said the Chang'e-3 mission has helped China to better understand the lunar environment and has paved the way for further explorations.

As the backup probe of Chang'e-3, Chang'e-4 should not repeat the mission, but do something more "innovative and meaningful", said Ye, without elaborating.

The more sophisticated Chang'e-5 mission, including unmanned sampling and returning, requires technology breakthroughs in moon surface takeoff, sampling encapsulation, rendezvous and docking in lunar orbit, as well as high-speed Earth reentry.

To make sure the returning mission is a success, a Chang'e-5 test probe will be launched this year to rehearse the route, Ye disclosed.

Chang'e-1 and Chang'e-2 missions were in 2007 and 2010.

Launched on Oct. 1, 2010, China's first man-made asteroid Chang'e-2 is now about 70 million km from Earth and continues heading to deep space.

Ye said the asteroid could travel as far as 300 million km from Earth.

Despite a latecomer in space development, China has made steady progress in recent years. It is the third nation, after the United States and Russia, to acquire the skills necessary for extravehicular activities and space docking.

Quelle: Xinhua

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2357 Views

Samstag, 1. März 2014 - 14:54 Uhr

Luftfahrt - Mega-Luftschiff Airlander in England vorgestellt

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Das Airlander genannte Luftschiff kann nach Herstellerangaben bis zu drei Woche in der Luft bleiben und bis zu 60 Tonnen transportieren.

Das ist der neue König der Lüfte

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Ist es ein Vogel? Ist es ein Flugzeug? Nein, es ist das größte Luftschiff der Welt. Mit dem "Airlander" ging in England ein neuer König der Lüfte vom Band. Der Heliumriese strotzt vor Superlativen.

In Großbritannien ist ein neuartiges Luftschiff vorgestellt worden, das laut seinem Hersteller über lange Zeit auf umweltfreundliche Weise große Lasten transportieren können soll. Das riesige Luftschiff, das an drei aneinander gefügte Zeppeline erinnert, wurde am Freitag in einem Hangar im mittelenglischen Cardington von der Herstellerfirma Hybrid Air Vehicles der Öffentlichkeit präsentiert. Ihren Angaben zufolge soll der mit Helium gefüllte Riese bis zu drei Wochen in der Luft bleiben und bis zu 60 Tonnen transportieren können.Das Airlander genannte Luftschiff, das mit 91 Metern noch länger als das russische Transportflugzeug Antonov An-225 ist, hat kurze Flügel und Rotoren als Antrieb. Es ist allerdings deutlich kleiner als der deutsche Zeppelin Hindenburg, der 244 Meter maß. Der Airlander wurde zunächst für das US-Militär entworfen, doch wurde der Auftrag nach Auslieferung des ersten Exemplars storniert. Die Herstellerfirma erhielt nun einen Staatskredit von 2,5 Millionen Pfund (drei Millionen Euro) und hat angekündigt, hunderte Luftschiffe bauen zu wollen.

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Make sure you take this truly once-in-a-lifetime opportunity

Win a pair of tickets to join our shareholder, Iron Maiden's Bruce Dickinson and a host of celebrities on this unique flight, complete with an invitation to our launch party*.

Our first passenger flight is scheduled to be in 2016. Join us on the maiden voyage over the skies of Bedfordshire and southern England in an entirely new type of aircraft.

The Airlander uses cutting edge materials and engineering, is environmentally friendly, innovative, and Britain at its best.

Its ground breaking technology will open up new capacities from delivering humanitarian aid to disaster zones with no runways, to opening up slow travel and unique ways of seeing our precious earth from the skies.

Quelle: Airlander

'World's longest aircraft' Airlander unveiled in Britain

LONDON: An airship-type vehicle billed by its makers as the world's longest aircraft currently in operation was unveiled in Britain on Friday.

The Airlander, which was originally developed for the US military, is 300 feet (91 metres) long, according its British maker Hybrid Air Vehicles.

The environmentally friendly helium-filled behemoth is designed to stay airborne for up to three weeks and can carry up to 60 tonnes, the company said.

It was shown off on Friday in a ..

LONDON: An airship-type vehicle billed by its makers as the world's longest aircraft currently in operation was unveiled in Britain on Friday.

The Airlander, which was originally developed for the US military, is 300 feet (91 metres) long, according its British maker Hybrid Air Vehicles.

The environmentally friendly helium-filled behemoth is designed to stay airborne for up to three weeks and can carry up to 60 tonnes, the company said.

It was shown off on Friday in a giant hangar in Cardington, central England, where great British airships of the past were built, including the ill-fated R101.

The R101 crashed in 1930 on its maiden voyage, killing 48 passenger and crew.

The new craft is longer than the current record holder, the Russian Antonov An-225, which is 84 metres long, and the Boeing 747-8, at 76 metres long.

But it is dwarfed by airships of the past such as the German zeppelin the Hindenburg, which was 244 metres long.

Filled with hydrogen, the Hindenburg famously crashed in the United States in 1937, killing 36 people.

The Airlander is essentially three streamlined airship-type bodies merged into one with wings and rotary engines.

It was built for the US military but the latter cancelled the contract after it was delivered.

Its makers, who have received a £2.5 million ($4.1 million, 3.0 million euro) British government grant, now say they intend to build hundreds of the aircraft.

British Business Secretary Vince Cable said the "innovative" craft "has the potential to lead the world in its field".
Quelle: ET

Tags: Airlander GB 

2905 Views

Samstag, 1. März 2014 - 12:17 Uhr

UFO-Forschung - Wie man seltsame Raumfahrt Fälle knackt

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How  to crack strange space cases
Lone sleuth uses the internet and his wits to solve ufo mysteries

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HOUSTON — When a space station astronaut made an offhand remark about an unusual formation of lights he saw passing in front of him during a spacewalk, the report had all the earmarks of an unsolvable space mystery. But it didn't take long to crack the case, thanks to the power of the Internet and one amateur space sleuth’s passion to find out.

It turned out that the case of the formation-flying lights was only the latest in a string of spooky space effects with perfectly natural explanations.

The investigation began when NASA astronaut Leroy Chiao told Aviation Week & Space Technology about "something interesting" he saw during a March 28 spacewalk with Russian crewmate Salizhan Sharipov.

“As the sun started rising after the first dark period, I looked out in the opposite direction of the sun and saw a line of five lights,” Chiao said. The lights seemed to be flying past fairly quickly "in an echelon formation, except that 'No. 2' was offset," he said.

Chiao admitted that he didn't know what the lights were, but he speculated that they might have been a constellation of satellites catching the sun's glint. Or perhaps they were "bright lights from oil platforms actually down on the Earth" that seemed to move due to the space station's own orbital speed.

Whatever they were, Chiao was delighted to have seen them. "It just shows you that after spending a lot of time in space and out on EVAs, there are still things that you can see that still surprise you," he mused.

Enter the investigator
One person who read the story was not surprised, since he had long been fascinated with unusual visual phenomena associated with space missions. James C. Smith, an aerospace engineer in Fairfax, Va., doesn't believe such phenomena are signs of alien visits. What he does believe — and what makes his work on this and other cases so impressive — is that such mysteries can often be solved, using resources available over the Internet. You just have to know where to look and what to do.


 
Based on Chiao's descriptions, Smith figured out the time and the station's location over Earth when the lights were sighted — and deduced that Chiao must have been looking toward the coast of South America, which was still shrouded by night

Smith knew that the place to go for images of bright lights on the night side of Earth was the home page of the Defense Meteorological Satellite Program, a military weather satellite network now closely integrated with the National Oceanographic and Atmospheric Administration.

After a day's worth of research, Smith came up with a solution to the mystery.

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Satellite imagery shows the lights of squid fishing boats off the coast of South America — lights that most likely piqued the interest of astronaut Leroy Chiao during a recent spacewalk at the international space station.

“A little research on the Internet shows that the area has a fleet of squid fishing boats which are the ones that use bright lights to attract the squid,” he reported by e-mail. "These unusually bright zones are the result of fleets of fishing vessels using powerful electrical lights at night to attract squid. The fleets regularly show up in images from weather satellites and from space stations."

Smith said Chiao was most likely looking at the fishing boats. “Since they are in the middle of a dark area of sea, and he was likely seeing them near the edge of his area of possible viewing, it may have been so dark opposite the sun that determining whether they were on the Earth surface or not may have been difficult,” Smith said.

“You can see that the lights are apparently brighter than any other lights around there,” he concluded. In photographs he obtained of the fleet that night, one light blob is indeed "off line" with a number of others. Viewed in the darkness below the onrushing space station, the lights would rapidly zoom off toward the horizon.

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Decades' worth of anomalies
Reports of space anomalies are almost as old as the space program itself: For instance, John Glenn, the first American to orbit the Earth, reported seeing clouds of "fireflies" outside his window outside his window during the 1962 spaceflight — sparkles of light that were later attributed to ice particles coming off his Mercury capsule.

Smith himself recently came up with the solution to a three-decade-old mystery, involving a strange image from the Apollo 16 moon mission in 1972: The picture, widely distributed among UFO investigators, showed a disk-shaped structure that was seen in 16mm movie footage shot out the window as the Apollo spacecraft left the moon and headed back toward Earth.

None of Apollo 16's astronauts mentioned the disk at the time. Later, one NASA photo technician misidentified the disk as the crescent Earth (it was in the wrong part of the sky), and other space experts speculated that it might be a window reflection of the camera lens itself. But there was no truly satisfactory explanation, and UFO enthusiasts seized upon the picture as evidence that a flying saucer may have been monitoring the moon mission.

In 2003, the Journal of Scientific Exploration, a scholarly-sounding publication that focuses on “anomalies and topics outside mainstream science.” contained an article about the Apollo 16 disk by Japanese engineer Hiroshi Nakamura. “We believe that the object is a large extraterrestrial artifact. ... This is the only hypothesis that is consistent with the data," Nakamura wrote.

Another case cracked
Smith’s interest was piqued, and he began digging into the case. On Sept. 29, 2003, he posted his own findings.

“I ordered all possible 16mm film and reviewed them all to locate the above image and to see if any explanation (lens flare, reflection, etc.) could be the cause of the image,” he reported. He also searched all NASA online references about the Apollo missions and the Apollo spacecraft mechanical systems, seeking potential correlations between the image and candidate hardware.

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This photo from the Apollo 16 moon mission seems to show a flying saucer. What does the image actually show?

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“Of interest is the more or less horizontal line or bar sticking out part of the UFO,” Smith pointed out, noting a feature that was visible in the high-quality film he had received — a feature unnoticed by all previous analysts. He then pored over the web pages for any disk-shaped structures mounted on long booms — and found one

“The most likely cause of the UFO object is the EVA floodlight,” he said. The pole-mounted lamp was set up to illuminate shadowy areas on the Apollo spacecraft, during an unusual spacewalk aimed at retrieving film from a mapping camera. The spacewalk occurred a day after the picture was taken.

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A sharper image of the Apollo 16 "flying saucer," produced from the original flight film, reveals a pole sticking out from the disk — which is actually a floodlight that was set up for a spacewalk.

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NASA weighs in
Meanwhile, a parallel line of inquiry was being set in motion by Donald Ratsch, a Maryland truck driver and UFO enthusiast. Ratsch was apparently unaware of Smith's conclusions, and on Oct. 27, 2003, he sent a letter to his congressman asking that NASA be required to explain the images.

About six months later, he received his reply: NASA had looked at the original flight film, and concluded that the image showed ... the EVA floodlight.

 

 
NASA
A NASA diagram from the Apollo era shows how the EVA floodlight was mounted on the spacecraft.

Gregory Byrne, a NASA imaging expert at Johnson Space Center in Houston, explained to MSNBC.com that the review was conducted “only because it was requested of us by NASA HQ in response to a congressional inquiry.”

“I had no choice in the matter,” Byrne said, “and reluctantly had to pull image analysis resources away from shuttle return-to-flight to work Apollo 16.  It actually turned out to be an interesting diversion from the tedium, and almost like stepping back in time.”

Quelle: NBC / J.Oberg


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Samstag, 1. März 2014 - 11:30 Uhr

Astronomie - Reaktivierte NEOWISE-Mission - Update

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24.01.2014

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Reaktivierte NEOWISE-Mission hat im ersten Monat bereits 857 kleine Körper im Sonnensystem, darunter 22 erdnahe Objekte (NEO) und vier Kometen entdeckt.

More than 100 asteroids were captured in this view from NASA's Wide-field Infrared Survey Explorer, or WISE, during its primary all-sky survey. Image credit: NASA/JPL-Caltech/UCLA

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In its first 25 days of operations, the newly reactivated NEOWISE mission has detected 857 minor bodies in our solar system, including 22 near-Earth objects (NEOs) and four comets. Three of the NEOs are new discoveries; all three are hundreds of meters in diameter and dark as coal.
The mission has just passed its post-restart survey readiness review, and the project has verified that the ability to measure asteroid positions and brightness is as good as it was before the spacecraft entered hibernation in early 2011. At the present rate, NEOWISE is observing and characterizing approximately one NEO per day, giving astronomers a much better idea of the objects' sizes and compositions.
Out of the more than 10,500 NEOs that have been discovered to date, only about 10 percent have had any physical measurements made of them; the reactivated NEOWISE will more than double that number.
JPL manages the NEOWISE mission for NASA's Science Mission Directorate in Washington. The Space Dynamics Laboratory in Logan, Utah, built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colo., built the spacecraft. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.
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The six red dots in this composite picture indicate the location of the first new near-Earth asteroid seen by NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) since the spacecraft came out of hibernation in December 2013. The asteroid, called 2013 YP139, is the first of hundreds of space-rock discoveries expected during its renewed mission. The inset shows a zoomed-in view of one of the detections of 2013 YP139. Image credit: NASA/JPL-Caltech
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NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft has spotted a never-before-seen asteroid -- its first such discovery since coming out of hibernation last year.
NEOWISE originally was called the Wide-field Infrared Survey Explorer (WISE), which had made the most comprehensive survey to date of asteroids and comets. The spacecraft was shut down in 2011 after its primary mission was completed. But in September 2013, it was reactivated, renamed and given a new mission, which is to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects (NEOs). NEOWISE also can assist in characterizing previously detected asteroids that could be considered potential targets for future exploration missions.
NEOWISE's first discovery of its renewed mission came on Dec. 29 -- a near-Earth asteroid designated 2013 YP139. The mission's sophisticated software picked out the moving object against a background of stationary stars. As NEOWISE circled Earth scanning the sky, it observed the asteroid several times over half a day before the object moved beyond its view. Researchers at the University of Arizona used the Spacewatch telescope at the Kitt Peak National Observatory southwest of Tucson to confirm the discovery. Peter Birtwhistle, an amateur astronomer at the Great Shefford Observatory in West Berkshire, England, also contributed follow-up observations. NASA expects 2013 YP139 will be the first of hundreds of asteroid discoveries for NEOWISE.
"We are delighted to get back to finding and characterizing asteroids and comets, especially those that come into Earth's neighborhood," said Amy Mainzer, the mission's principal investigator from NASA's Jet Propulsion Laboratory in Pasadena, Calif. "With our infrared sensors that detect heat, we can learn about their sizes and reflectiveness."
2013 YP139 is about 27 million miles (43 million kilometers) from Earth. Based on its infrared brightness, scientists estimate it to be roughly 0.4 miles (650 meters) in diameter and extremely dark, like a piece of coal. The asteroid circles the sun in an elliptical orbit tilted to the plane of our solar system and is classified as potentially hazardous. It is possible for its orbit to bring it as close as 300,000 miles from Earth, a little more than the distance to the moon. However, it will not come that close within the next century.
WISE discovered more than 34,000 asteroids and characterized 158,000 throughout the solar system during its prime mission in 2010 and early 2011. Its reactivation in September followed 31 months in hibernation.
NEOWISE will continue to detect asteroids and comets. The observations will be automatically sent to the clearinghouse for solar system bodies, the Minor Planet Center in Cambridge, Mass., for comparison against the known catalog of solar system objects and to determine orbit if the object is not known. A community of professional and amateur astronomers will provide follow-up observations, establishing firm orbits for the previously unseen objects.
Infrared sensors, similar to the cameras on NEOWISE, are a powerful tool for discovering, cataloging and understanding the asteroid population. Some of the objects about which NEOWISE will be collecting data could become candidates for NASA's announced asteroid initiative, which will be the first mission to identify, capture and relocate an asteroid for astronauts to explore. The initiative represents an unprecedented technological feat that will lead to new scientific discoveries and technological capabilities that will help protect our home planet and achieve the goal of sending humans to an asteroid by 2025.
JPL manages the project for NASA's Science Mission Directorate in Washington. The Space Dynamics Laboratory in Logan, Utah, built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colo., built the spacecraft. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.
Quelle: NASA
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Update: 1.03.2014
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NEOWISE entdeckt seinen ersten Kometen:C/2014 C3
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Comet NEOWISE was first observed by NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft on Valentine's Day, 2014.
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NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft has spotted a never-before-seen comet -- its first such discovery since coming out of hibernation late last year.

"We are so pleased to have discovered this frozen visitor from the outermost reaches of our solar system," said Amy Mainzer, the mission's principal investigator from NASA's Jet Propulsion Laboratory in Pasadena, Calif. "This comet is a weirdo - it is in a retrograde orbit, meaning that it orbits the sun in the opposite sense from Earth and the other planets."

Officially named "C/2014 C3 (NEOWISE)", the first comet discovery of the renewed mission came on Feb. 14 when the comet was about 143 million miles (230 million kilometers) from Earth. Although the comet's orbit is still a bit uncertain, it appears to have arrived from its most distant point in the region of the outer planets. The mission's sophisticated software picked out the moving object against a background of stationary stars. As NEOWISE circled Earth, scanning the sky, it observed the comet six times over half a day before the object moved out of its view. The discovery was confirmed by the Minor Planet Center, Cambridge, Mass., when follow-up observations were received three days later from the Near Earth Object Observation project Spacewatch, Tucson, Ariz. Other follow-up observations were then quickly received. While this is the first comet NEOWISE has discovered since coming out of hibernation, the spacecraft is credited with the discovery of 21 other comets during its primary mission.

Originally called the Wide-field Infrared Survey Explorer (WISE), the spacecraft was shut down in 2011 after its primary mission was completed. In September 2013, it was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects. NEOWISE will also characterize previously known asteroids and comets to better understand their sizes and compositions.

JPL manages the NEOWISE mission for NASA's Science Mission Directorate in Washington. The Space Dynamics Laboratory in Logan, Utah, built the science instrument. Ball Aerospace & Technologies Corp. of Boulder, Colo., built the spacecraft. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.

Quelle: NASA


Tags: NEOWISE-Mission 

2425 Views

Freitag, 28. Februar 2014 - 18:39 Uhr

Raumfahrt - Skepsis gegenüber bemannter Mars-Vorbeiflug-Idee 2021

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A hurry-up launch in 2021 for a human flyby of Mars proposed by pioneer space tourist Dennis Tito would make a good “bridge” between the International Space Station and more sustainable missions closer to Earth, according to experts testifying before a skeptical House Science Committee Feb. 27.

The mission would require an advanced version of NASA’s heavy-lift Space Launch System (SLS) and other new hardware to take advantage of a unique opportunity to reach Mars with a gravity assist from Venus. Committee witnesses were unwilling to put a price tag on that work, and conservative members of the panel said they were uneasy with open-ended spending for a high-risk project on a tight deadline.

“Do you really see right now that there’s a commitment in this country so that we don’t start down this trail, spending a lot of money, and then at the end of the trail not have accomplished the mission because the window wasn’t there?” Rep. Dana Rohrabacher (R-Calif.), asked Sandra Magnus, executive director of the American Institute of Aeronautics and Astronautics.

Magnus, an astronaut and former ISS crew member, had testified that the U.S. would be capable of conducting the mission, provided Congress makes adequate funds available. Tito, who was the first “spaceflight participant” to purchase a ride to the space station on a Russian Soyuz crew vehicle, has testified that he could tap “private philanthropy” for $300 million toward the 2021 mission, and believes NASA could develop the necessary hardware for $100 million a year over the next seven years.

“I continue to believe, as do many Americans, that Mars is the logical destination to put human space exploration back on track and demonstrate the ‘can do’ spirit that seems to have faded over time,” Tito said in a statement after the hearing. “The window of opportunity in 2021 is challenging but achievable and waiting to be claimed.”

Doug Cooke, a former NASA associate administrator for exploration systems who has advised Tito’s Inspiration Mars Foundation on the Mars flyby, testified that the 70-ton variant of the SLS is on track for its critical design review this year, and an instrumented prototype of NASA’s Orion multipurpose crew vehicle is set for a Delta IV flight test in September. That test is designed to validate the design of the heat shield that would be needed to protect an Orion returning from the vicinity of the Moon, but Cooke testified that a more robust shield would be needed for the planetary-return velocities associated with reentry after a Mars flyby.

Also required by 2021 would be the advanced, “dual-use” upper stage on NASA’s books to take the SLS to its intermediate, 105-ton capability to low Earth orbit. Ultimately, the agency plans to add advanced strap-on boosters to give the big rocket the 130-ton-to-LEO capability Congress mandated.

After detailed study, Tito and his engineers rejected an early concept of a 501-day direct flight around Mars with a two-person crew during a particularly opportune launch window in 2018, and opted instead for the 580-day flight in 2021 that would fly by Venus and Earth before heading to Mars. Once there, Cooke said, the Orion crew would have 40 hours to observe the Red Planet from a distance that would make it appear at least as large as the Moon from Earth.

The mission also would require a habitat with advanced life support systems where the crew would reside during the long transits between planets, Cooke said. Tito funded a year-long study by Paragon Space Development Corp. that produced a benchtop life support system. The system appeared to meet the 2021 requirements, but testing on the ISS probably would be required. The habitat itself could be an Orbital Sciences Corp. Cygnus commercial cargo module, or perhaps an inflatable habitat provided by Bigelow Aerospace, according to Taber MacCallum, the Paragon CEO and chief technology officer.

Scott Pace, director of the Space Policy Institute at George Washington University and a White House and NASA official under President George W. Bush, testified that he personally would favor a return to the Moon as the next human step beyond low Earth orbit. But the 2021 flyby would be a useful project to focus development on the systems that would be needed for work in cislunar space, asteroids and perhaps the Martian moons that would not require development of an expensive lander.

“The Mars flyby mission serves as an interesting potential bridge between where we are with the ISS, where we would like to be with Mars, and where our international partners and commercial opportunities are with human spaceflight beyond low Earth orbit,” Pace said.

Quelle: Aviationweek


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