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Why NASA plans to crash a spacecraft into an asteroid

Bruce Willis can relax: European and North American 

space agencies have joined forces to prevent an 

asteroid armageddon. Phil Ritchie reports on the mission.


Asteroids have always posed an extinction-level threat to Earth. Most famously, an impact 65 million years ago wiped out around three-quarters of the Earth’s species, including

 the non-birdlike dinosaurs.

Luckily, the chance of another cataclysmic collision is so low we’re unlikely to see one anytime soon. Still – even a minuscule chance is a chance, and eventually, our 

number will come up.

That’s why, in a bid to beef up our planetary defence 

systems, NASA and the European Space Agency (ESA) may mount the first mission to shove an asteroid out of its 

normal trajectory – by crashing a spacecraft into it.

The mission, called the Asteroid Impact and Deflection Assessment (AIDA), actually comprises two smaller

 operations: the Asteroid Impact Mission (AIM), coordinated by the ESA, and the Double Asteroid Redirection Test (DART) on NASA’s end.

If the ESA’s Ministerial Council gives the plan the thumbs 

up in December, it will transition from concept to reality.

Their target is the 800-metre-wide asteroid 65803 Didymos, or more precisely its 170-metre-wide satellite, dubbed Didymoon.

The asteroid pair will come as close as 16 million kilometres from Earth in 2022 – a perfect opportunity for such an experimental mission, because the asteroids will still be far enough away so there will be no chance of accidentally sending one hurtling towards us.

AIM is the first of the two operations to take flight. It will launch from Kourou in South America aboard a Russian Soyuz-Fregat rocket towards the end of 2020.

Once in space, it will deploy solar panels and manoeuvre towards Didymoon.

Once at its destination, it will orbit the two asteroids and conduct preliminary observations from a safe distance. 

But it will also be a rendezvous point for DART when it arrives to crash into the little moon some months later, at which point AIM will move out of the way.

AIM’s job is to assess Didymoon’s structure, composition, rotation and orbit and send that information back to 

Earth. To do so, it will use an assortment of equipment

 such as thermal and visual cameras, an optical laser and radar.

To assist taking these measurements, several other 

vessels will drop out of AIM when it’s in orbit.

A Mascot-2 lander, built by the German Aerospace 

Centre, will land on and conduct an on-site assessment 

of the asteroid, including its mineral make-up, brightness, temperature and radiation. At least two CubeSats – toaster-sized satellites – will also be deployed from AIM. They will observe from positions too risky for the larger AIM mothership.

Part two of the mission – the 300-kilogram DART spacecraft – will depart Earth a few months after AIM. As its name suggests, it will crash into Didymoon at six kilometres per second. Its purpose: to bump Didymoon out of its orbit.

Unlike data-gathering AIM, the only equipment DART will carry is a camera to help its automatic guiding system hit its mark.

AIM will watch closely as DART collides with Didymoon and calculate the results of the impact. And in the aftermath, AIM and its vessels will perform before-and-after comparisons on the structure of the asteroid and its orbit.

Should AIDA get the go-ahead this December, it will mark an important stepping stone as the first time humans have tried shifting a celestial object’s trajectory.

Whether a success or failure, the mission’s data beamed back will be worth the projected mission cost of US$300 million.

As asteroids are scraps left over from the formation of the Solar System, it will provide insights into how ours was formed while providing the groundwork to one day deflect an asteroid – should we be unlucky enough down the track.

 

Why NASA plans to crash a spacecraft into an asteroid
Bruce Willis can relax: European and North American space agencies have joined forces to prevent an asteroid armageddon. Phil Ritchie reports on the mission.
 An artist's impression of the Asteroid Impact Mission taking notes as the Double Asteroid Redirection Test crashes into Didymoon.CREDIT: ESA / SCIENCE OFFICE
Asteroids have always posed an extinction-level threat to Earth. Most famously, an impact 65 million years ago wiped out around three-quarters of the Earth’s species, including the non-birdlike dinosaurs.
Luckily, the chance of another cataclysmic collision is so low we’re unlikely to see one anytime soon. Still – even a minuscule chance is a chance, and eventually, our number will come up.
That’s why, in a bid to beef up our planetary defence systems, NASA and the European Space Agency (ESA) may mount the first mission to shove an asteroid out of its normal trajectory – by crashing a spacecraft into it.
The mission, called the Asteroid Impact and Deflection Assessment (AIDA), actually comprises two smaller operations: the Asteroid Impact Mission (AIM), coordinated by the ESA, and the Double Asteroid Redirection Test (DART) on NASA’s end.
If the ESA’s Ministerial Council gives the plan the thumbs up in December, it will transition from concept to reality.
Their target is the 800-metre-wide asteroid 65803 Didymos, or more precisely its 170-metre-wide satellite, dubbed Didymoon.
The asteroid pair will come as close as 16 million kilometres from Earth in 2022 – a perfect opportunity for such an experimental mission, because the asteroids will still be far enough away so there will be no chance of accidentally sending one hurtling towards us.
AIM is the first of the two operations to take flight. It will launch from Kourou in South America aboard a Russian Soyuz-Fregat rocket towards the end of 2020.
Once in space, it will deploy solar panels and manoeuvre towards Didymoon.
Once at its destination, it will orbit the two asteroids and conduct preliminary observations from a safe distance. But it will also be a rendezvous point for DART when it arrives to crash into the little moon some months later, at which point AIM will move out of the way.
AIM’s job is to assess Didymoon’s structure, composition, rotation and orbit and send that information back to Earth. To do so, it will use an assortment of equipment such as thermal and visual cameras, an optical laser and radar.
To assist taking these measurements, several other vessels will drop out of AIM when it’s in orbit.
A Mascot-2 lander, built by the German Aerospace Centre, will land on and conduct an on-site assessment of the asteroid, including its mineral make-up, brightness, temperature and radiation. At least two CubeSats – toaster-sized satellites – will also be deployed from AIM. They will observe from positions too risky for the larger AIM mothership.
Part two of the mission – the 300-kilogram DART spacecraft – will depart Earth a few months after AIM. As its name suggests, it will crash into Didymoon at six kilometres per second. Its purpose: to bump Didymoon out of its orbit. 
Unlike data-gathering AIM, the only equipment DART will carry is a camera to help its automatic guiding system hit its mark.
AIM will watch closely as DART collides with Didymoon and calculate the results of the impact. And in the aftermath, AIM and its vessels will perform before-and-after comparisons on the structure of the asteroid and its orbit.
Should AIDA get the go-ahead this December, it will mark an important stepping stone as the first time humans have tried shifting a celestial object’s trajectory.
Whether a success or failure, the mission’s data beamed back will be worth the projected mission cost of US$300 million.
As asteroids are scraps left over from the formation of the Solar System, it will provide insights into how ours was formed while providing the groundwork to one day deflect an asteroid – should we be unlucky enough down the track.

Key results from Comet 67P: No earthly water, no magnetic field
 Published studies undermine the entire theory of planetary formation but suggests organic compounds can be delivered by comets.
 
It was thought that in the early days of the Solar System, 4.6 billion years ago, magnetic fields helped rubble to clump together to become planets. Philae’s bouncy landing allowed it to measure magnetic fields across different sites and heights above the comet. The only magnetic field it detected came from the Sun. Researchers analysing Philae’s magnetometer data reported that the comet lacked a magnetic field.
 
The comet’s lack of overall magnetic fields suggests that, if magnetism did play a role in the early Solar System, it was only to help clump dust particles and pebbles smaller than a metre in size.
 
In the journal Science in July this year, two separate teams reported that Philae detected organic material, including four compounds never before seen on a comet. While the teams didn’t identify amino acids, they did detect several possible amino acid precursors.
 
What about water? Another of the mission’s surprises is that the assumption that comets are filled with water that could have built the oceans on earth is probably incorrect.
 
Earth’s water has a specific ratio of normal water to “heavy” water (in heavy water one of the hydrogen atoms is replaced with a slightly heavier deuterium atom). But the water on 67P has three times as much heavy water as the Earth. So this type of comet couldn’t have been the source of Earth’s water.

 

 

 

Driving the gravity tractor


NASA Announces Make-Work Mission to Find an Asteroid with

a loose boulder and whatever……Ya know, bring it back

somewhere, somehow to learn how to save the earth.

 

 

"NASA will use the opportunity to test planetary defense techniques to help mitigate potential asteroid impact threats in the future."

 

On March 27, 2014 NASA announced more details in its plan for its Asteroid  Redirect Mission  (ARM), which in the mid-2020s will test a number of new capabilities needed for future human expeditions

to deep space, including to Mars. 

 

NASA also announced it has increased the detection of near-Earth 

asteroids by 65 percent since launching its asteroid initiative three

years ago.

 

For ARM, a robotic spacecraft will capture a boulder from the surface

 of a near-Earth asteroid and move it into a stable orbit around the

 moon for exploration by astronauts, all in support of advancing the 

nation’s journey to Mars. No, really!

 

"The Asteroid Redirect Mission will provide an initial demonstration of several spaceflight capabilities we will need to send astronauts deeper 

into space, and eventually, to Mars," said NASA Associate Administrator Robert Lightfoot. "The option to retrieve a boulder from an asteroid will 

have a direct impact on planning for future human missions to deep 

space and begin a new era of spaceflight."

 

The agency plans to announce the specific asteroid selected for the 

mission no earlier than 2019, approximately a year before launching 

the robotic spacecraft.

 

Before an asteroid is considered a valid candidate for the mission, 

scientists must first determine its characteristics, in addition to size

such as rotation, shape and precise orbit. NASA has identified three valid candidates for the mission so far: Itokawa, Bennu and 2008 EV5.

The agency expects to identify one or two additional candidates each year leading up to the mission.


NASA did not explain how, at that vast distance, it could possibly 
know if the selected asteroid embraced a boulder that fit the 
bill in terms of mass and removability.

 

Nevertheless, following its rendezvous with the target asteroid, the uncrewed ARM spacecraft will just up and deploy robotic arms and then maneuver somehow to capture just the right boulder that just happens 

to be sitting on the surface. It then will begin a multi-year journey to redirect the boulder into orbit around the moon.

 

Throughout its mission, the ARM robotic spacecraft will test a number

 of capabilities needed for future human missions, including

 advanced Solar Electric Propulsion (SEP), a valuable capability 

that converts sunlight to electrical power through solar arrays and

 then uses the resulting power to propel charged atoms to move a spacecraft. This method of propulsion can move massive cargo very efficiently. While slower than conventional 

chemical rocket propulsion, SEP-powered spacecraft require significantly

 less propellant and fewer launches to support human exploration 

missions, which could reduce costs.

 

Future SEP-powered spacecraft could pre-position cargo or vehicles 

for future human  missions into deep space, either awaiting crews 

at Mars or staged around the moon as a waypoint for expeditions to

the Red Planet.



ARM's SEP-powered robotic spacecraft will test new trajectory and 

navigation techniques in deep space, working with the moon's gravity

 to place the asteroid in a stable lunar orbit called a distant retrograde

 orbit. This is a suitable staging point for astronauts to rendezvous with a 

deep space habitat that will carry them to Mars.

 

Before the piece of the asteroid is moved to lunar orbit, NASA will 

use the opportunity to test planetary defense techniques to help

mitigate potential asteroid impact threats in the future.

The experience and knowledge acquired through this operation 

will help NASA develop options to move an asteroid off an 

Earth-impacting course, if and when that becomes necessary.

 

In 2005, NASA's Deep Impact comet science mission tested technology 

that could assist in changing the course of a near-Earth object using a

 direct hit with a spacecraft. The ARM robotic spacecraft opens a new and second option for planetary defense using a technique called a gravity tractor. 


All mass exerts and experiences gravity and, in space, the gravitational attraction even between masses of modest size can significantly affect 

their motion. This means that by rendezvousing with the asteroid and holding a halo orbit in the appropriate direction, the ARM robotic spacecraft can slowly pull the asteroid without touching it.

 

The effectiveness of this maneuver is increased, moreover, if mass is 

moved from the asteroid to the spacecraft by the capture of a boulder.

It will take approximately six years for the ARM robotic spacecraft to 

move the asteroid mass into lunar orbit. In the mid-2020s, NASA's 

Orion spacecraft will launch on the agency’s Space Launch System 

rocket, carrying astronauts on a mission to rendezvous with and explore the asteroid mass. 


The current concept for the crewed mission component of ARM is a two-astronaut, 24-25 day mission.

 

This crewed mission will further test many capabilities needed to 

advance human spaceflight for deep space missions to Mars and 

elsewhere, including new sensor technologies and a docking system 

that will connect Orion to the robotic spacecraft carrying the asteroid 

mass. Astronauts will conduct spacewalks outside Orion to study 

and collect samples of the asteroid boulder wearing new spacesuits

designed for deep space missions.

 

Collecting these samples will help astronauts and mission managers determine how best to secure and safely return samples from future 

Mars missions. And, because asteroids are made of remnants from the formation of the solar system, the returned samples could provide 

valuable data for scientific research or commercial entities interested in asteroid mining as a future resources.


In 2012, the president's NASA budget included, and Congress 

authorized, $20.4 million for an expanded NASA Near-Earth Object

(NEO) Observations Program, increasing the resources for this critical program from the $4 million per year it had received since the 1990s. 

The program was again expanded in fiscal year 2014, with a budget 

of $40.5 million. 


NASA is asking Congress for $50 million for this important work in 

the 2016 budget.

 

"Asteroids are a hot topic," said Jim Green, director of NASA Planetary Science.

"Not just because they could pose a threat to Earth, but also for their scientific value and NASA's planned mission to one as a stepping 

stone to Mars."


NASA has identified more than 12,000 NEOs to date, including 96 

percent of near-Earth asteroids larger than 0.6 miles (1 kilometer) 

in size. NASA has not detected any objects of this size that pose an

 impact hazard to Earth in the next 100 years. Smaller asteroids do 

pass near Earth, however, and some could pose an impact threat. 

In 2011, 893 near-Earth asteroids were found.  In 2014, that

number was increased to 1,472.


The harder they look the more threatening rocks they find, which is the actual primary justification for this exercise.

 

In addition to NASA's ongoing work detecting and cataloging asteroids, 

the agency has engaged the public in the hunt for these space rocks 

through the agency's Asteroid Grand Challenge activities, including prize competitions. 


During the recent South by Southwest Festival in Austin, Texas, the agency announced the release of a software application based on an algorithm created by a NASA challenge that has the potential to increase the number of new asteroid discoveries by amateur astronomers.


More information about the Asteroid Redirect Mission, visit:

/asteroidinitiative

All Three NASA Mars Orbiters Healthy After Comet Flyby

All three NASA orbiters around Mars confirmed their healthy status Sunday after each took shelter behind Mars during a period of risk from dust released by a passing comet.

Mars Odyssey, Mars Reconnaissance Orbiter and the Mars Atmosphere and Volatile Evolution (MAVEN) orbiter all are part of a campaign to study comet C/2013 A1 Siding Spring and possible effects on the Martian atmosphere from gases and dust released by the comet. The comet sped past Mars today much closer than any other know comet flyby of a planet.

Read mission status reports from each of the three orbiters at:

› Mars Odyssey mission status report

› Mars Reconnaissance Orbiter mission status report

› MAVEN mission status report

 

NASA Scientists Find Evidence of Water in Meteorite, Reviving Debate Over Life on Mars

Microtunnels in Yamato Meteorite From MarsThis scanning electron microscope image of a polished thin section of a meteorite from Mars shows tunnels and curved microtunnels. Image Credit: NASA
› Full image and caption
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February 27, 2014

A team of scientists at NASA's Johnson Space Center in Houston and the Jet Propulsion Laboratory in Pasadena, Calif., has found evidence of past water movement throughout a Martian meteorite, reviving debate in the scientific community over life on Mars.

In 1996, a group of scientists at Johnson led by David McKay, Everett Gibson and Kathie Thomas-Keprta published an article in Science announcing the discovery of biogenic evidence in the Allen Hills 84001(ALH84001) meteorite. In this new study, Gibson and his colleagues focused on structures deep within a 30-pound (3.7-kilogram) Martian meteorite known as Yamato 000593 (Y000593). The team reports that newly discovered different structures and compositional features within the larger Yamato meteorite suggest biological processes might have been at work on Mars hundreds of millions of years ago.

The team's findings have been published in the February issue of the journal Astrobiology. The lead author, Lauren White, is based at the Jet Propulsion Laboratory. Co-authors are Gibson, Thomas-Keprta, Simon Clemett and McKay, all based at Johnson. McKay, who led the team that studied the ALH84001 meteorite, died a year ago.

"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 White. "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."

Analyses found that the rock was formed about 1.3 billion years ago from a lava flow on Mars. Around 12 million years ago, an impact occurred on Mars which ejected the meteorite from the surface of Mars. The meteorite traveled through space until it fell in Antarctica about 50,000 years ago.

The rock was found on the Yamato Glacier in Antarctica by the Japanese Antarctic Research Expedition in 2000. The meteorite was classified as a nakhlite, a subgroup of Martian meteorites. Martian meteoritic material is distinguished from other meteorites and materials from Earth and the moon by the composition of the oxygen atoms within the silicate minerals and trapped Martian atmospheric gases.

The team found two distinctive sets of features associated with Martian-derived clay. They found tunnel and micro-tunnel structures that thread their way throughout Yamato 000593. The observed micro-tunnels display curved, undulating shapes consistent with bio-alteration textures observed in terrestrial basaltic glasses, previously reported by researchers who study interactions of bacteria with basaltic materials on Earth.

The second set of features consists of nanometer- to-micrometer-sized spherules that are sandwiched between layers within the rock and are distinct from carbonate and the underlying silicate layer. Similar spherical features have been previously seen in the Martian meteorite Nakhla that fell in 1911 in Egypt. Composition measurements 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 50,000 years residence time, are similar to features found in Nakhla, an observed fall collected shortly after landing.

The authors note that they cannot exclude the possibility that the carbon-rich 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.

"The unique features displayed within the Martian meteorite Yamato 000593 are evidence of aqueous alterations as seen in the clay minerals and the presence of carbonaceous matter associated with the clay phases which show that Mars has been a very active body in its past," said Gibson. "The planet is revealing the presence of an active water reservoir that may also have a significant carbon component.

"The nature and distribution of Martian carbon is one of the major goals of the Mars Exploration Program. Since we have found indigenous carbon in several Mars meteorites, we cannot overstate the importance of having Martian samples available to study in earth-based laboratories. Furthermore, the small sizes of the carbonaceous features within the Yamato 000593 meteorite present major challenges to any analyses attempted by remote techniques on Mars," Gibson added.

"This is no smoking gun," said JPL's White. "We can never eliminate the possibility of contamination in any meteorite. But these features are nonetheless interesting and show that further studies of these meteorites should continue."

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov 

The Meteors

Earthlike biolstructures in Mars Meteor

Tiny Blobs and Tunnels in Meteorite Revive Debate Over Life on Mars

BY ALAN BOYLE

Eighteen years after a Martian meteorite sparked a debate over alien-looking "nanofossils," researchers are reporting that different structures inside an even bigger space rock suggest biological processes might have been at work on the Red Planet hundreds of millions of years ago.

"We're convinced that this is another one of the important data points that is going toward answering the big question: Was there life on Mars?" Everett Gibson, a researcher at NASA's Johnson Space Center who was involved in both studies, told NBC News.

He made clear, however, that even the latest study won't settle the big question. "We don't come out and say we have found life on Mars," Gibson said.

Microscopic structures

Gibson and his colleagues focused on microscopic structures deep within a 30-pound (13.5 kilogram) meteorite known as Yamato 000593, which was found in Antarctica by a Japanese team in 2000. An analysis of the rock's composition showed that it was formed on Mars about 1.3 billion years ago and altered by interaction with water on Mars. Scientists say the rock was blasted into space by a cosmic impact and fell to Earth within the past 10,000 years.

In February's issue of the journal Astrobiology, the research team — led by Lauren White of NASA's Jet Propulsion Laboratory — describes microscopic tunnels that thread their way through the meteorite's interior, as well as tiny blobs of carbon-rich minerals that are embedded within layers of rock.

WHITE ET AL. / ASTROBIOLOGY

This photomicrograph shows bands of minerals inside a meteorite from Mars, including "micro-tunnels" that researchers say are suggestive of microbial weathering.

WHITE ET AL. / ASTROBIOLOGY

The red circle in this photomicrograph highlights spherules in a meteorite from Mars that are enriched in carbon, compared with the background material indicated within the blue circle.

The team says such structures are suggestive of ancient weathering through biological processes. If the meteorite had come from the bottom of Earth's oceans, "we'd say, 'Gee, this rock contains evidence that there was microbial activity that was eating away at the rock,'" Gibson said.

The researchers emphasize that they "cannot exclude the possibility that the carbon-rich regions in both sets of features" are the product of non-biological processes. However, they say the "textural and compositional similarities to features in terrestrial samples, which have been interpreted as biogenetic, imply the intriguing possibility that the Martian features were formed by biotic activity."

White told NBC News that she didn't want to make any "life on Mars" claim prematurely. "I definitely don't think this is a 'smoking gun' paper," she said. "I want the reader to decide in the context of everything that we show."

Revisiting controversy

A similar tale was told in 1996 about a Martian meteorite known as ALH84001. Back then, researchers said that chemical analysis as well as wormlike features they called nanofossils supported their view that life was once present. The report caused a sensation — but other experts insisted that the features weren't biological in origin. As a result, the "life on Mars" claims faded into scientific limbo.

Since then, Gibson and other researchers who were involved in the original ALH84001 study have been trying to gather more evidence for their case. White joined the team as a summer-session researcher in 2007 and was asked to take a close look at Yamato 000593. "Who's going to turn that down, right?" she said.

White was intrigued by the micro-tunnels and the spherules, and worked with other researchers to determine they were similar to geological features on Earth created through biological processes. The key challenge was to show that the features were the result of activity on Mars rather than earthly contamination. "Whatever these features are, the data suggests they likely originated from Mars," White said.

One of the paper's authors was NASA scientist David McKay, who took center stage during the controversy over ALH84001. McKay died a year ago after a long struggle with heart problems. His health difficulties complicated the years-long publication process.

"He was actually working on this paper the day he passed away," White said. "I promised his wife that I would publish this paper, because it meant so much to him to keep this work going."

Skepticism persists

Most planetary scientists accept the view that Mars was once warmer, wetter and more Earthlike — and thus more hospitable to life — than it is today. It's also plausible to suggest that if life did exist on ancient Mars, it should have left characteristic traces in rocks from the Red Planet. But the evidence laid out in the Astrobiology paper isn't likely to settle the controversy.

"I don't think the science community will find 'textural and compositional similarities' compelling enough to be proof of a biological origin," Chris McKay, an astrobiologist at NASA's Ames Research Center and no relation to David McKay, told NBC News in an email.

"We have our critics, and that's what science is all about."

Gibson acknowledged that the case for life on Mars is far from closed. "We have our critics, and that's what science is all about," he said.

He and his colleagues are following up on their findings with more detailed chemical analysis. "We have to go to the next step of going in there and tearing these carbon molecules apart," Gibson said.

NASA's Curiosity rover is searching for evidence of organic carbon on the Red Planet. But to settle the big question conclusively will probably require bringing fresh rock samples back from Mars and analyzing them on Earth with high-precision scientific instruments. That could take a decade or more.

"Until that time, we need to use the best thing we have," Gibson said, "and that's the meteorites from Mars."

In addition to White, Gibson and McKay, the authors of"Putative Indigenous Carbon-Bearing Alteration Features in Martian Meteorite Yamato 000593" include Kathie Thomas-Keprta and Simon Clemett.

Tip o' the Log to NBC News space analyst James Oberg.

NBC News' Alan Boyle will discuss the latest from Mars as well as developments in commercial spaceflight from 10 to 11:30 p.m. ET Tuesday on "The Space Show," a live streaming-audio program hosted by Dr. David M. Livingston.

 

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