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Space News Update — September 23, 2016 —

Contents

In the News

Story 1: NASA-Funded Sounding Rocket Solves One Cosmic Mystery, Reveals Another

Story 2: Hubble Finds Planet Orbiting Pair of Stars

Story 3: Rosetta’s Final Days of Comet Exploration

Departments

The Night Sky

ISS Sighting Opportunities

Space Calendar

NASA-TV Highlights

Food for Thought

Space Image of the Week

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1. NASA-Funded Sounding Rocket Solves One Cosmic Mystery, Reveals Another

In the last century, humans realized that space is filled with types of light we can’t see – from infrared signals released by hot stars and galaxies, to the cosmic microwave background that comes from every corner of the universe. Some of this invisible light that fills space takes the form of X-rays, the source of which has been hotly contended over the past few decades.

It wasn’t until the flight of the DXL sounding rocket, short for Diffuse X-ray emission from the Local galaxy, that scientists had concrete answers about the X-rays’ sources. In a new study, published Sept. 23, 2016, in the Astrophysical Journal, DXL’s data confirms some of our ideas about where these X-rays come from, in turn strengthening our understanding of our solar neighborhood’s early history. But it also reveals a new mystery – an entire group of X-rays that don’t come from any known source.

The two known sources of X-ray emission are the solar wind, the sea of solar material that fills the solar system, and the Local Hot Bubble, a theorized area of hot interstellar material that surrounds our solar system.

“We show that the X-ray contribution from the solar wind charge exchange is about forty percent in the galactic plane, and even less elsewhere,” said Massimiliano Galeazzi, an astrophysicist at the University of Miami and an author on the study. “So the rest of the X-rays must come from the Local Hot Bubble, proving that it exists.”

However, DXL also measured some high-energy X-rays that couldn’t possibly come from the solar wind or the Local Hot Bubble.

“At higher energies, these sources contribute less than a quarter of the X-ray emission,” said Youaraj Uprety, lead author on the study and an astrophysicist at University of Miami at the time the research was conducted. “So there’s an unknown source of X-rays in this energy range.”

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In the decades since we first discovered the X-ray emission that permeates space, three main theories have been bandied about to explain its origins. First, and quickly ruled out, was the idea that these X-rays are a kind of background noise, coming from the distant reaches of the universe. Our galaxy has lots of neutral gas that would absorb X-rays coming from distant sources – meaning that these X-rays must originate somewhere near our solar system.

So what could produce this kind of X-ray so close to our solar system? Scientists theorized that there was a huge bubble of hot ionized gas enveloping our solar system, with electrons energetic enough that they could release X-rays like this. They called this structure the Local Hot Bubble.

“We think that around 10 million years ago, a supernova exploded and ionized the gas of the Local Hot Bubble,” said Galeazzi. “But one supernova wouldn’t be enough to create such a large cavity and reach these temperatures – so it was probably two or three supernova over time, one inside the other.”

The Local Hot Bubble was the prevailing theory for many years. Then, in the late 1990s, scientists discovered another source of X-rays – a process called solar wind charge exchange.

Our sun is constantly releasing solar material in all directions, a flow of charged particles called the solar wind. Like the sun, the solar wind is made up of ionized gas, where electrons and ions have separated. This means that the solar wind can carry electric and magnetic fields.

When the charged solar wind interacts with pockets of neutral gas, where the electrons and ions are still tightly bound together, it can pick up electrons from these neutral particles, exciting them. As these electrons settle back into a stable state, they lose energy in the form of X-rays – the same type of X-rays that had been thought to come from the Local Hot Bubble.

The discovery of this solar wind X-ray source posed a problem for the Local Hot Bubble theory, since the only indication that it existed were these X-ray observations. But if the hot bubble did exist, it could tell us a lot about how our corner of the galaxy formed.

“Identifying the X-ray contribution of the Local Hot Bubble is important for understanding the structure surrounding our solar system,” said Uprety, who is now an astrophysicist at Middle Tennessee State University. “It helps us build better models of the interstellar material in our solar neighborhood.”

Distinguishing between X-rays from the solar wind and X-rays from the Local Hot Bubble was a challenge – that’s where DXL comes in. DXL flew on what's called a sounding rocket, which flies for some 15 minutes. These few minutes of observing time above Earth’s atmosphere are valuable, since Earth’s blocks most of these X-rays, making observations like this impossible from the ground. Such short-duration sounding rockets provide a relatively inexpensive way to gather robust space observations.

DXL is the second spacecraft to measure the X-rays in question, but unlike the previous mission – a satellite called ROSAT – DXL flew at a time when Earth was passing through something called the helium-focusing cone. The helium-focusing cone is a region of space where neutral helium is several times denser than in the rest of the inner solar system.

“The solar system is moving through interstellar space at about 15 miles per second,” said Uprety. “This space is filled with hydrogen and helium. The helium is a little heavier, so it carves around the sun to form a tail.”

Because solar wind charge exchange is dependent on having lots of neutral material to interact with, measuring X-rays in the helium-focusing cone could help scientists definitively determine how much of the X-ray emission comes from the solar wind, and how much – if any – comes from the Local Hot Bubble.

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DXL’s data revealed that about forty percent of most observed X-rays come from the solar wind. But in higher energy ranges, some X-rays are still unexplained. DXL’s observations show that less than a quarter of the X-ray emission at higher energy levels comes from the solar wind, and the Local Hot Bubble isn’t a good explanation either.

“The temperature of the Local Hot Bubble is not high enough to produce X-rays in this energy range,” said Uprety. “So we’re left with an open question on the source of these X-rays.”

Source: NASA Return to Contents

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2. Hubble Finds Planet Orbiting Pair of Stars

Two's company, but three might not always be a crowd — at least in space.

Astronomers using NASA's Hubble Space Telescope, and a trick of nature, have confirmed the existence of a planet orbiting two stars in the system OGLE-2007-BLG-349, located 8,000 light-years away towards the center of our galaxy.

The planet orbits roughly 300 million miles from the stellar duo, about the distance from the asteroid belt to our sun. It completes an orbit around both stars roughly every seven years. The two red dwarf stars are a mere 7 million miles apart, or 14 times the diameter of the moon's orbit around Earth.

The Hubble observations represent the first time such a three-body system has been confirmed using the gravitational microlensing technique. Gravitational microlensing occurs when the gravity of a foreground star bends and amplifies the light of a background star that momentarily aligns with it. The particular character of the light magnification can reveal clues to the nature of the foreground star and any associated planets.

The three objects were discovered in 2007 by an international collaboration of five different groups: Microlensing Observations in Astrophysics (MOA), the Optical Gravitational Lensing Experiment (OGLE), the Microlensing Follow-up Network (MicroFUN), the Probing Lensing Anomalies Network (PLANET), and the Robonet Collaboration. These ground-based observations uncovered a star and a planet, but a detailed analysis also revealed a third body that astronomers could not definitively identify.

"The ground-based observations suggested two possible scenarios for the three-body system: a Saturn-mass planet orbiting a close binary star pair or a Saturn-mass and an Earth-mass planet orbiting a single star," explained David Bennett of the NASA Goddard Space Flight Center in Greenbelt, Maryland, the paper's first author.

The sharpness of the Hubble images allowed the research team to separate the background source star and the lensing star from their neighbors in the very crowded star field. The Hubble observations revealed that the starlight from the foreground lens system was too faint to be a single star, but it had the brightness expected for two closely orbiting red dwarf stars, which are fainter and less massive than our sun. "So, the model with two stars and one planet is the only one consistent with the Hubble data," Bennett said.

Bennett's team conducted the follow-up observations with Hubble's Wide Field Planetary Camera 2. "We were helped in the analysis by the almost perfect alignment of the foreground binary stars with the background star, which greatly magnified the light and allowed us to see the signal of the two stars," Bennett explained.

Kepler has discovered 10 other planets orbiting tight binary stars, but these are all much closer to their stars than the one studied by Hubble.

Now that the team has shown that microlensing can successfully detect planets orbiting double-star systems, Hubble could provide an essential role in this new realm in the continued search for exoplanets.

The team's results have been accepted for publication in The Astronomical Journal.

Source: NASA Return to Contents

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3. Rosetta’s Final Days of Comet Exploration

An amazing mission of cometary exploration is about to come to aclimactic end next week, as the European Space Agency's Rosetta spacecraft comes to rest on Comet 67P/Churyumov-Gerasimenko on September 30.

Launched on March 2, 2004, from Kourou, French Guiana, atop an Ariane 5 rocket, it took Rosetta 10 years to arrive at Comet 67P. This epic journey included flybys of Mars, Earth and asteroids 2867 Steins and 21 Lutetia, after which Rosetta was placed in a risky hibernation mode for several years. Reawakened on January 20, 2014, Rosetta successfully phoned home and got to work.

Thanks to Rosetta, Comet 67P is now arguably the most studied comet in the history of planetary science.

Don't Call it an Impact

Up until now, Rosetta has kept a good distance from Comet 67P, but in its last days, the final orbits of Rosetta will bring it as close as a kilometer from the surface of the comet.

Rosetta will execute its low-speed collision maneuver 20 kilometers above the comet's surface late on the evening of Thursday, September 29th. Contact is set to occur later the next day during a 20-minute window centered on 10:40 Universal Time (UT) — Comet 67P is 40 light-minutes distant, so it will take that long for ESA to receive . Rosetta is expected to come to rest on the comet at a velocity of about 1 meter per second. That's about 3.6 kilometers per hour (2.2 mph, equivalent to a slow walking pace).

“We have observations/measurements of the comet at all scales, from kilometers down to 100s of nanometers and this is giving us a wonderful insight into how the comet was created from the interstellar dust,” says

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project scientist Matt Taylor (ESA) “We have shown that the comet was formed from two smaller similar cometesimals that collided at low velocity.”

The Ma'at region that Rosetta is targeting is dotted with several active sink hole-style pits, measuring about 100 meters wide by 50 meters deep (imagine a football field-sized hole as deep as a typical water tower is high). Researchers plan to bring Rosetta down on a smooth plain between the Ma'at 02 and Ma'at 03 depressions, in hopes of peering inside them.

Pits on Comet 67P show strange meter-sized nodules sometimes called "goosebumps." Scientists believe these lumps could be cometesimals which merged together to create the comet during the origin of the early solar system.

Instruments will continue to measure gas, dust, and plasma all the way down during Rosetta’s descent, including during the 2 kilometers closest to the comet, where some particles and ions in the coma begin accelerating toward the comet's tail. “This is something we have NEVER done with Rosetta,” Taylor says.

The mission team christened the Ma'at 02 pit as Deir el-Medina, after an ancient pit in Egypt that proved to be a modern archaeological treasure trove.

Science and the Final Days of Rosetta

The Rosetta mission provides proof that big projects spanning decades can pay off. We've learned about the dynamic processes on comets that turn them into beautiful celestial spectacles.

Rosetta has also shown that water ice on Comet 67P contains three times more deuterium than water on Earth, disputing primordial comets as the source of Earth's water. Rosetta did, however, discover glycine and other complex compounds on Comet 67P, offering a possible source for delivering organic compounds to early Earth.

And just within a month of the mission's end, Rosetta amazed us once again on September 5th, as the team released images of the Philae lander wedged in a dark crack on the comet's surface. This answered a lingering mystery as to just why Philae had a such rough time phoning home, as it received little sunlight to charge its batteries.

Will we hear from Rosetta again, if it survives surface contact? “No, the spacecraft will be commanded to not try to re-contact Earth,” Says Taylor. “As Jim Morrison once said: 'This is the end... beautiful friend.'”

Still it's fun to wonder just what the final fate of Rosetta and Philae might be over the coming millennia. Discovered in 1969, Comet 67P orbits the Sun once every 6.44 years, its distance ranging from 1.2 to 5.7 astronomical units (a.u., the distance between Earth the Sun). Most likely, the twin lobes of Comet 67P will one day break apart, and perhaps, Philae and Rosetta will once again drift free and derelict around the Sun.

Congrats to ESA and the Rosetta team on an amazing and inspiring mission, as Rosetta joins Philae on a final strange and exotic resting place on the surface of a comet.

Watch the ESA hangout discussing the final fate of Rosetta.

Source: Sky & Telescope Return to Contents

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The Night Sky Friday, September 23 • The starry W of Cassiopeia stands high in the northeast after dark. The right-hand side of the W (the brightest side) is tilted up.

Look along the second segment of the W counting down from the top. Notice the dim naked-eye stars along that segment (not counting its two ends). The one on the right is Eta Cassiopeiae, magnitude 3.4, a Sun-like star just 19 light-years away with an orange-dwarf companion — a lovely binary in a telescope.

The "one" on the left, fainter, is a wide naked-eye pair: Upsilon1 and Upsilon2Cassiopeiae, 0.3° apart. They're orange giants unrelated to each other, 200 and 400 light-years from us.

• Last-quarter Moon (exact at 5:56 a.m. Eastern Daylight Time on this date). The Moon rises around midnight or 1 a.m. on the morning of Saturday the 24th. Once it's fairly well up you'll see that it's in Gemini, with Castor and Pollux to its left. Orion is much farther to its right.

• Algol is at its minimum light, magnitude 3.4 instead of its usual 2.1, for about two hours centered on 11:19 p.m. EDT. Info and comparison-star chart.

Saturday, September 24 • This is the time of year when the rich Cygnus Milky Way crosses the zenith in the hour after nightfall is complete (for skywatchers at mid-northern latitudes). The Milky Way rises straight up from the southwest horizon, passed overhead, and runs straight down to the northeast.

Sunday, September 25 • About a half hour after sunset, you shouldn't have much trouble spotting Venus very low in the west-southwest through the twilight, if you have a clear view down that low.

But can you see twinkly little Spica 2½° beneath Venus, perhaps as twilight fades further? You'll likely need binoculars or a telescope, the more so the farther north you live. Spica is only magnitude +1.0 compared to Venus's –3.9. In other words, it's only 1% as bright. (And that's before the more severe atmospheric extinction for lower Spica.)

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Monday, September 26 • Arcturus shines in the west these evenings as twilight fades out. Equally-bright Capella (they're both magnitude 0) is barely rising in the north-northeast, depending on your latitude; the farther north you are, the higher it will be. Late in the evening, Arcturus and Capella shine at the same height in their respective compass directions. When will this happen? It depends on both your latitude and longitude.

• Early Tuesday morning the 27th, the waning crescent Moon is about 6° upper right of Regulus (for North America), as shown at right. Look 17° below or lower right of Regulus for Mercury.

Tuesday, September 27 • This is the time of year when, during the evening, the dim Little Dipper "dumps water" into the bowl of the Big Dipper way down below. The Big Dipper will dump it back in the evenings of spring.

• As dawn brightens Wednesday morning the 28th, spot the thin crescent Moon between Regulus above it and Mercury below it, as shown at right.

Source: Sky & Telescope Return to Contents

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ISS Sighting Opportunities

For Denver: Date Visible Max Height Appears Disappears

Fri Sep 23, 4:45 AM 2 min 39° 39° above ENE 11° above ESE

Fri Sep 23, 6:18 AM 5 min 18° 10° above W 10° above S

Sat Sep 24, 5:29 AM 3 min 36° 36° above SW 10° above SSE

Sun Sep 25, 4:40 AM < 1 min 10° 10° above SE 10° above SE

Mon Sep 26, 8:22 PM < 1 min 11° 11° above S 11° above S

Tue Sep 27, 7:31 PM 2 min 13° 10° above SSE 12° above ESE

Tue Sep 27, 9:05 PM < 1 min 12° 10° above WSW 12° above WSW

Sighting information for other cities can be found at NASA’s Satellite Sighting Information

NASA-TV Highlights (all times Eastern Daylight Time)

• Check NASA-TV’s Upcoming Events listing for multiple viewing times of ISS Expedition 49 in-Flight Interviews.

Watch NASA TV on the Net by going to the NASA website. Return to Contents

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Space Calendar • Sep 23 - Cassini, Orbital Trim Maneuver #460 (OTM-460) • Sep 23 - Comet 73P-AA/Schwassmann-Wachmann Closest Approach To Earth (1.081 AU) • Sep 23 - Comet 338P/McNaught Closest Approach To Earth (1.356 AU) • Sep 23 - Comet 31P/Schwassmann-Wachmann At Opposition (3.703 AU) • Sep 23 - Comet 294P/LINEAR At Opposition (4.100 AU) • Sep 23 - Asteroid 43844 Rowling Closest Approach To Earth (1.283 AU) • Sep 23 - Asteroid 9951 Tyrannosaurus Closest Approach To Earth (1.346 AU) • Sep 23 - Asteroid 12490 Leiden Closest Approach To Earth (2.517 AU) • Sep 23 - Kuiper Belt Object 308933 (2006 SQ372) At Opposition (26.252 AU) • Sep 23 - Kuiper Belt Object 120347 Salacia At Opposition (43.735 AU) • Sep 23 - Willie McCool's 55th Birthday (1961) • Sep 23 - 170th Anniversary (1846), Johann Galle's Discovery of Neptune • Sep 23 - Johann Encke's 225th Birthday (1791) • Sep 24 - Cassini, Distant Flyby of Polydeuces • Sep 24 - Comet 62P/Tsuchinshan Closest Approach To Earth (2.797 AU) • Sep 24 - Asteroid 441 Bathilde Occults HIP 38092 (6.9 Magnitude Star) • Sep 24 - Asteroid 6216 San Jose Closest Approach To Earth (1.588 AU) • Sep 24 - Asteroid 5608 Olmos Closest Approach To Earth (1.589 AU) • Sep 24 - Asteroid 2200 Pasadena Closest Approach To Earth (1.750 AU) • Sep 24 - Educator Workshop: Comets Close Up, Pasadena, California • Sep 24 - 5th Anniversary (2011), UARS Reenters Earth's Atmosphere • Sep 24 - Pols Swings' 110th Birthday (1906) • Sep 25 - Comet 73P-BE/Schwassmann-Wachmann Perihelion (1.006 AU) • Sep 25 - Comet 343P/NEAT-LONEOS Closest Approach To Earth (1.545 AU) • Sep 25 - Comet 24P/Schaumasse At Opposition (3.121 AU) • Sep 25 - Comet 123P/West-Hartley At Opposition (4.027 AU) • Sep 25 - Apollo Asteroid 2016 RL20 Near-Earth Flyby (0.047 AU) • Sep 25 - Apollo Asteroid 363831 (2005 PY16) Near-Earth Flyby (0.075 AU) • Sep 25 - Asteroid 3850 Peltier Closest Approach To Earth (0.930 AU) • Sep 25 - Atira Asteroid 164294 (2004 XZ130) Closest Approach To Earth (1.139 AU) • Sep 25 - Asteroid 8952 ODAS Closest Approach To Earth (1.646 AU) • Sep 26 - [Sep 21] WorldView 4 (GeoEye 2) Atlas 5 Launch • Sep 26 - [Sep 20] ScatSat 1 PSLV Launch • Sep 26 - Comet P/2008 SH164 (LINEAR) Closest Approach To Earth (2.174 AU) • Sep 26 - Comet 86P/Wild Closest Approach To Earth (2.868 AU) • Sep 26 - Comet C/2011 KP36 (Spacewatch) Closest Approach To Earth (3.971 AU) • Sep 26 - [Sep 20] Apollo Asteroid 2016 RH40 Near-Earth Flyby (0.048 AU) • Sep 26 - Asteroid 8622 Mayimbialik Closest Approach To Earth (1.579 AU) • Sep 27 - [Sep 22] Cassini, Titan Flyby • Sep 27 - Comet 73P-BH/Schwassmann-Wachmann Perihelion (1.005 AU) • Sep 27 - Comet 73P-BI/Schwassmann-Wachmann Perihelion (1.005 AU) • Sep 27 - Comet 73P-BM/Schwassmann-Wachmann Perihelion (1.005 AU) • Sep 27 - Comet 73P-BP/Schwassmann-Wachmann Perihelion (1.005 AU) • Sep 27 - Comet 175P/Hergenrother At Opposition (3.906 AU) • Sep 27 - Comet C/2015 V3 (PANSTARRS) At Opposition (4.281 AU) • Sep 27 - Amor Asteroid 2016 QB2 Near-Earth Flyby (0.081 AU) • Sep 27 - Asteroid 10168 Stony Ridge Closest Approach To Earth (1.583 AU) • Sep 27 - Asteroid 243097 Batavia Closest Approach To Earth (1.641 AU) • Sep 27 - Asteroid 2791 Paradise Closest Approach To Earth (1.701 AU) • Sep 27 - Asteroid 54522 Menaechmus Closest Approach To Earth (1.945 AU)

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• Sep 27 - Plutino 469372 (2001 QF298) At Opposition (42.405 AU) • Sep 27 - Stephanie Wilson's 50th Birthday (1966) • Sep 27 - Alberto Conti's 50th Birthday (1966) • Sep 27 - 60th Anniversary (1956), 1st Man to Reach Mach 3 (Mel Apt)

Source: JPL Space Calendar Return to Contents

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Food for Thought

NASA to have limited role in SpaceX’s planned Mars campaign

Expertise, input and advice from seasoned NASA engineers will improve SpaceX’s chances of nailing the first commercial landing on Mars as soon as late 2018, a senior space agency official said Wednesday, but Elon Musk’s space transport company will likely seek more independence from U.S. government support on later expeditions to the red planet.

While considered high risk by NASA standards, the Red Dragon Mars mission revealed by SpaceX in April has a “reasonable likelihood” of success, according to Phil McAlister, NASA’s director of commercial spaceflight development.

McAlister said NASA will act as a consultant to SpaceX on the Red Dragon project, the first of a series of Mars landers planned by the Hawthorne, California-based company. NASA’s participation will diminish in later missions, he said.

“NASA’s role is somewhat limited,” McAlister said in a conference call with space industry experts Wednesday. “We don’t have full insight into the overall mission design, nor should we.”

SpaceX plans multiple robotic Mars missions over the next decade leading up to a human expedition. It is all part of Elon Musk’s long-term vision to colonize Mars, a topic the business mogul plans to discuss in detail during a presentation at the International Astronautical Congress in Guadalajara, Mexico, next week.

The company’s first Mars mission — Red Dragon — is slated to launch from Cape Canaveral as soon as May 2018 aboard a Falcon Heavy rocket, SpaceX’s heavy-lift launcher that is now scheduled for its maiden flight in the first quarter of 2017.

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SpaceX recently announced the Falcon Heavy’s debut will slip from later this year as the company investigates a major launch pad mishap Sept. 1 that destroyed a Falcon 9 rocket and its communications satellite payload.

Any impact from the accident on Red Dragon’s 2018 launch date — a schedule NASA officials already said was ambitious — is unclear.

Red Dragon will not carry any people — Dragon is not designed to transport astronauts all the way to Mars on its own — but it is based on the human-rated spaceship SpaceX is developing under the auspices of NASA’s commercial crew program to haul residents between Earth and the International Space Station.

Musk has hinted at a concept for an “Interplanetary Colonial Transporter” to ferry people from Earth to Mars and beyond. The system would be launched by a giant rocket that is still on the drawing board.

McAlister said SpaceX approached NASA in late 2015 seeking help with the Red Dragon mission, and the parties concluded an agreement in April. NASA is not providing any funds to SpaceX, but the agency is contributing labor and expertise valued at approximately $32 million over four years, according to Jim Reuter, deputy associate administrator for programs in NASA’s space technology mission directorate.

Reuter said in July that he estimates SpaceX is spending about 10 times more than NASA’s planned expenditure on Red Dragon, or roughly $300 million.

SpaceX has not said how much it is spending on Red Dragon, and McAlister did not offer his own cost estimate Wednesday.

“NASA’s participation, the way SpaceX characterized it, is it was highly desired, but it was not enabling necessarily,” McAlister said. “Our participation, we believe, will increase the likelihood that it will be successful, and SpaceX agrees with that, too… But SpaceX could eventually do all this on their own.”

he Red Dragon spacecraft will weigh between 8 and 10 tons when it lands, Reuter said in July, up to ten times heavier than the Curiosity rover, largest vehicle ever to reach the Martian surface.

A new type of landing system is needed to accommodate the leap in mass, replacing braking parachutes with rocket engines.

NASA engineers believe supersonic retro-propulsion, using thrust from large rocket engines to do the parachute’s job, is the best way to deliver hefty spacecraft to the Martian surface. The Red Dragon spacecraft’s SuperDraco thrusters, mounted in pairs on four pods outside the capsule, will ignite at supersonic speed after the ship passes through the hottest part of its entry into Mars’ atmosphere.

Landing legs should deploy just before the craft settles onto Martian soil.

McAlister said all of NASA’s concepts for placing large habitats and crews on Mars employ supersonic retro-propulsion, a capability already demonstrated by SpaceX in Earth’s atmosphere during recoveries of the company’s large Falcon 9 first stage boosters.

NASA needs data on how supersonic retro-propulsion works at Mars before sending people there, and McAlister said the Red Dragon partnership will give NASA the results it needs “at least a decade sooner and at a small fraction of the cost” than if the agency developed its own mission.

“We don’t even have a mission on the books, so it’s not even clear how long it would take, but certainly at least a decade,” McAlister said.

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“They like to get 80 percent of the answers sooner, as opposed to getting 95 percent of the answers later,” McAlister said of SpaceX. “They’ve got a desire to get on with this.”

Earlier this year, Musk said SpaceX intends to send a robotic mission to Mars during every launch opportunity. Mars launch windows come about every 26 months when the planets are properly positioned in their orbits.

“SpaceX’s goal is to increase their independence from NASA on each mission as fast as possible,” McAlister said. “The heaviest reliance will obviously be on this first mission.

“How fast that happens is completely to be determined,” McAlister said. “We’ll have to see, but I would suspect future campaigns to be potentially more independent as we go forward.”

NASA will provide deep space communications support to Red Dragon through a network of dish antennas in California, Spain and Australia, and experts at the Jet Propulsion Laboratory will provide navigation solutions to help plot the spacecraft’s trajectory.

Government engineers will give advice to SpaceX on the capsule’s entry, descent and landing at Mars, the design of the spacecraft and its heat shield, and the aerodynamic environment in the rarefied Martian atmosphere.

“In return, we are receiving most of SpaceX’s EDL (entry, descent and landing) flight data,” McAlister said. “This is a critical, critical technology for us. This is flight data that would not be available for us by any other means.”

NASA is also charged with advising SpaceX on planetary protection and the steps required to ensure the Dragon capsule does not contaminate Mars with Earth-based microbes, which could ruin future research into potential extant or past life there.

McAlister said the government is still working on a plan to certify or approve commercial spacecraft for landings on other planets. The Red Dragon mission is “charting new territory” in planetary protection requirements and oversight authority, he said.

“The paradigm for approving this mission is still somewhat immature,” he said. “It’s not necessarily NASA’s role to approve that. It is the responsiblity of the U.S. government. We are still working out the roles and responsibilities among the various agencies.”

NASA, the Federal Aviation Administration and the U.S. State Department might be involved in that process, he said.

SpaceX and NASA are also discussing whether Red Dragon could fly with research instruments, such as payloads to demonstrate how future astronauts could live off resources in the Martian environment.

McAlister said NASA would not share data on the Red Dragon’s performance during entry, descent and landing, but lessons learned could improve the agency’s computer models.

“This has never been done before — putting a large mass into the Mars atmosphere using supersonic retro-propulsion,” McAlister said.

NASA aims to put human crews in orbit around Mars by the mid-2030s.

Two keystones of that plan are the Space Launch System heavy-lift rocket and Orion crew capsule. NASA may procure commercially-built habitats and electric propulsion units for the half-year trips to and from Mars.

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McAlister said he sees SpaceX’s Mars efforts as vital to NASA’s “Journey to Mars,” an often-repeated tagline that permeates the space agency’s communications and public relations campaigns.

“We need efforts of all U.S. capabilities, NASA and the private sector, if we’re going to be successful on our ‘Journey to Mars,'” he said Wednesday. “We’re going to Mars as a nation. It’s not just NASA’s journey. It’s U.S.-led, but (it’s) even an international journey.

“I think redundancy — multiple capabilities to do even the same thing — I see that as a feature, not a bug,” McAlister said. “We’ve seen through crew, and particularly cargo, to the International Space Station (that when) one system goes down and another system can do the same thing, that is a strength.

“I don’t believe in having one uber czar in charge of a specific technology or a specific capability.”

SpaceX’s own privately-developed Mars exploration plan would rely on the company’s own rockets and spaceships, plus other systems expected to be revealed by Musk on Sept. 27.

“SLS has got its own unique mission,” McAlister said. “It’s a very difficult mission. It’s going to be one of the biggest launch vehicles ever built, and we’re going to need that if we do deep space exploration.”

Source: Spaceflight Now Return to Contents

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Space Image of the Week

Harvest Moon Eclipse Image Credit & Copyright: Miguel Claro (TWAN, Dark Sky Alqueva)

Explanation: A Harvest Moon rises over Sesimbra Castle south of Lisbon in this impressive series of telephoto exposures. Captured at its full phase, the golden Moon was also gliding through the Earth's more diffuse outer shadow during September's penumbral lunar eclipse. The eclipse shading is subtle compared to a total lunar eclipse. Still, the penumbral shadow does darken the Moon's upper limb, the pale shadow receding as the Moon climbs into Portugal's evening sky. In this eclipse timelapse the effect of sunlight and earthshadow on the Moon looks remarkably like the coloring of light and shadow along the illuminated castle walls.

Source: APOD Return to Contents