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From: "Moon, Larry J. (JSC-EA411)" <larry.j.moon@nasa.gov>
Date: November 29, 2013 8:35:35 AM CST
To: "Moon, Larry J. (JSC-EA411)" <larry.j.moon@nasa.gov>
Subject: FW: NASA and Human Spaceflight News Nov. 29, 2013
Happy Friday—hope all of you had a wonderful Thanksgiving! Have a great weekend.NASA and Human Spaceflight NewsFriday – November 29, 2013HEADLINES AND LEADSSpaceX Thanksgiving Day launch scrubbed — twiceKate Santich – Orlando SentinelTwo attempts to launch a SpaceX commercial satellite were aborted Thursday evening — each within the final minute of the countdown.SpaceX launch on hold after launch abortWilliam Harwood – CBS NewsAlready running three days late, launch of an upgraded SpaceX Falcon 9 rocket carrying a commercial communications satellite -- the company's first -- was aborted Thursday two seconds after the booster's nine first stage engines began throttling up for takeoff from the Cape Canaveral Air Force Station.SpaceX Scrubs Falcon 9's First Geo Mission AgainAmy Svitak – Aviation WeekFor the second time this week Space Exploration Technologies (SpaceX) has postponed the first launch of its Falcon 9 v1.1 to geosynchronous transfer orbit from Cape Canaveral AFS, Fla., this time due to a slow ramp-up in thrust on the rocket's nine first-stage engines.SpaceX hopes to try yet again in a 'few' daysJames Dean – Florida TodaySpaceX hopes a Falcon 9 rocket is ready for a third launch attempt within a few days, after coming within one second of a Thanksgiving Day blastoff from Cape Canaveral.JAXA to send Onishi to ISS in 2016The Japan TimesThe Japan Aerospace Exploration Agency said Friday that astronaut Takuya Onishi will travel into space for the first time around July 2016 in a Russian Soyuz spacecraft.Comet ISON lives up to reputation for surprisesWilliam Harwood – CBS NewsAfter a multi-million-year plunge from the frozen fringes of the solar system, Comet ISON may have broken apart and evaporated in the fierce heat and crushing gravity of the sun before or during a close flyby Thursday, presumably scotching long-held hopes for a dramatic sky show on Earth over the next few weeks.Did Comet ISON survive? Scientists see tiny hopeAssociated PressScientists were studying spacecraft images Friday to find out whether a small part of Comet ISON survived its close encounter with the sun.COMPLETE STORIESSpaceX Thanksgiving Day launch scrubbed — twiceKate Santich – Orlando SentinelTwo attempts to launch a SpaceX commercial satellite were aborted Thursday evening — each within the final minute of the countdown.The Falcon 9 rocket, carrying a communications satellite, was initially scheduled to launch at 5:39 p.m. but was called off at virtually the last second. Another attempt at 6:44 p.m. was scrubbed at T-minus 58 seconds.Among the features of the rocket — which Space-X CEO Elon Musk calls the most advanced in the world — is an automated engine shutdown if computers detect any problems.Musk said another launch attempt likely won't come for a few days. Engineers must first lower the rocket to a horizontal position and move it to a hangar for inspections. The launch already had been postponed after an initial attempt on Monday failed. The issue at that time turned out to be a valve problem.The source of Thursday's woes is still unknown, a SpaceX spokesman said.Musk has said a successful launch could bring more commercial satellite business to the U.S. — a potential boon for the Space Coast's ailing economy.SpaceX launch on hold after launch abortWilliam Harwood – CBS NewsAlready running three days late, launch of an upgraded SpaceX Falcon 9 rocket carrying a commercial communications satellite -- the company's first -- was aborted Thursday two seconds after the booster's nine first stage engines began throttling up for takeoff from the Cape Canaveral Air Force Station.
The engines were safely shut down and SpaceX engineers, believing the underlying problem could be resolved, recycled the countdown for a second launch try at 6:44 p.m. EST (GMT-5), the end of a 65-minute window. But with less than a minute to go, the countdown was interrupted again when an engineer on the countdown network called "hold, hold, hold.""This is the LD on countdown net," the launch director said a few minutes later. "We have scrubbed for the day. We'll continue through the abort safing and go into de-tank and site securing. We did call a hold at approximately T-minus 60 seconds. Essentially, we just ran out of time to complete data review from the first engine start.
"So taking the safe path out here, we decided to abort for the day and do sufficient, complete data review. So stand by for more information on our recycle timeline."
A launch opportunity was available Friday, but Elon Musk, SpaceX founder and chief designer, said in a Twitter posting earlier that in the event of a second abort, the rocket's tanks would be drained and the booster lowered to horizontal for a detailed engine inspection.
"We called manual abort," he tweeted. "Better to be paranoid and wrong. Bringing rocket down to borescope (inspect) engines."
As a result, he said earlier, another launch attempt likely will be delayed by a few more days.
This will be only the second flight of an upgraded SpaceX Falcon 9, featuring stretched propellant tanks, a new flight computer and more efficient engines. It is also the company's first flight with a non-government commercial satellite on board.
Perched atop the rocket in a protective nose cone was a 24-transponder GEOStar 2 relay station built by Orbital Sciences Corp. and owned by SES World Skies, a Luxembourg-based company that operates a fleet of more than 50 communications stations.
Martin Halliwell, the chief technology officer of SES, said the company decided to risk a satellite on the first launch of an upgraded Falcon 9 because of a growing need for an alternative, less expensive rocket to offset higher satellite costs and lower revenue streams in emerging markets.
SpaceX already holds a $1.6 billion NASA contract to launch unmanned Dragon cargo ships to the International Space Station and the company is competing for contracts to build a manned version of the rocket and capsule to ferry crews to and from the outpost.
But Musk wants to claim a share of the commercial satellite launch market now dominated by Arianespace, the European consortium that markets Ariane 5 rockets, and International Launch Services, or ILS, which sells Russian-built Proton rockets.
The SES-8 relay station atop the Falcon 9 is valued at around $100 million. The exact cost of the rocket is not known, but the SpaceX website advertises prices between $56.5 million and $77.1 million.
For comparison, Protons are believed to sell for around $100 million while a heavy-lift Ariane 5, which typically carries two satellites at a time, is believed to run around $200 million to $225 million per rocket.
Thierry Guillemin, chief technical officer of Intelsat, a major satellite operator, told Spaceflight Now that SpaceX "has already infused a lot of positive energy and they are poised to be a game-changer. Of course, this particular launch is extremely important for us operators in geostationary orbit. This is the real deal now."
He said SpaceX's competitors will "have to work on the cost side one way or the other. This is all good news for commercial operators and Intelsat in particular."
The dramatic engine start and shutdown Thursday came at the end of an otherwise smooth countdown, three days after a last-minute scrub Monday caused by concern about unusual oxygen pressurization readings in the rocket's first stage.
SpaceX engineers immediately "safed" the towering rocket after Thursday's abort and recycled the countdown in hopes of resolving the problem before the launch window closed.
In a tweet after the shutdown, Musk said the Falcon 9's nine first stage engines did not appear to be throttling up as rapidly as expected, prompting a computer-ordered abort as a safety precaution.
After studying telemetry, engineers decided the engines probably were operating in an acceptable range and they pressed ahead for another launch try.
But that was contingent on a full understanding of the engine abort and throttle sequence and as the countdown ticked into its final minute, engineers decided they needed more time to review the data.SpaceX Scrubs Falcon 9's First Geo Mission AgainAmy Svitak – Aviation WeekFor the second time this week Space Exploration Technologies (SpaceX) has postponed the first launch of its Falcon 9 v1.1 to geosynchronous transfer orbit from Cape Canaveral AFS, Fla., this time due to a slow ramp-up in thrust on the rocket's nine first-stage engines.The Nov. 28 mission was expected to carry the Orbital Sciences Corp.-built SES-8 satellite to a geosynchronous transfer orbit of 295 km x 80,000 km altitude and an inclination of 20.75 deg. for Luxembourg-based SES, the world's second largest commercial fleet operator by revenue.At T-0 seconds into the launch sequence, however, the Falcon 9 flight computer aborted the mission after igniting all nine of the rocket's nine Merlin 1D engines. The abort, which was called at the beginning of a 65-minute launch window beginning at 5:39 p.m. EST, was due to a slower-than-expected ramp up in thrust, according to Falcon 9 Product Manager John Insprucker.After sifting through data from the aborted launch attempt, mission managers set a new launch target of 6:44 p.m. At 6:28 p.m., Insprucker said SpaceX had "made some modifications in the ground systems" and was ready for another launch attempt. At T-48 seconds, however, mission managers aborted the recycled launch attempt, postponing the mission for several days to review data from the first stage engines."The expectation is we will detank the rocket, bring it horizontal, most likely bring it back into the hangar, do some inspections, determine the path forward and then be ready to attempt another launch probably within a few days," Insprucker said.The delay follows a Nov. 25 launch attempt that was scrubbed owing to pressure fluctuations on the Falcon 9's first stage liquid oxygen tank, after which the Falcon 9's first and second stages were detanked and the rocket was rolled back to the hangar. Insprucker said "everything looked good" and tat mission managers addressed the pressurization issue by modifying the countdown sequence for topping off the rocket's oxygen tank.SpaceX hopes to try yet again in a 'few' daysJames Dean – Florida TodaySpaceX hopes a Falcon 9 rocket is ready for a third launch attempt within a few days, after coming within one second of a Thanksgiving Day blastoff from Cape Canaveral.The rocket's nine first-stage engines fired at 5:39 p.m. Thursday, but shut down when computers sensed their thrust was building up too slowly.The countdown was restarted in an effort to pull off a launch before the window closed at 6:44 p.m., but engineers ran out of time to analyze data from the engine cutoff and called off the attempt with a minute left."Better to be paranoid and wrong," tweeted CEO Elon Musk.Musk said the rocket would return to its hangar for engine inspections at Cape Canaveral Air Force Station's Launch Complex 40.No new date was immediately set for the launch of SES-8, a communications satellite owned by Luxembourg-based SES.A first launch attempt on Monday scrubbed because of fluctuating pressures in the rocket booster's liquid oxygen tank, SpaceX said.SpaceX is trying to launch an upgraded version of the Falcon 9 that has flown only once before, on a September test flight from California.This mission would be the company's first of a commercial satellite, after several successful deliveries of cargo to the International Space Station launched by the original Falcon 9.A launch Thursday would have been the first from the Cape on Thanksgiving since 1959.But that launch ended in failure. Musk's better-safe-than-sorry strategy made sure history would not repeat itself.JAXA to send Onishi to ISS in 2016The Japan TimesThe Japan Aerospace Exploration Agency said Friday that astronaut Takuya Onishi will travel into space for the first time around July 2016 in a Russian Soyuz spacecraft.Onishi, 37, who will stay at the International Space Station for about six months, issued a comment saying: "I'm glad from the bottom of my heart. I hope I can convey the various charms of space so children will feel it is familiar to them."He will be the 11th Japanese to travel into space. The 10th is Kimiya Yui, 43, who is scheduled to stay at the ISS in 2015.After studying aerospace engineering at the University of Tokyo, Onishi served as a co-pilot at All Nippon Airways Co. and was chosen as an astronaut candidate in 2009.Comet ISON lives up to reputation for surprisesWilliam Harwood – CBS NewsAfter a multi-million-year plunge from the frozen fringes of the solar system, Comet ISON may have broken apart and evaporated in the fierce heat and crushing gravity of the sun before or during a close flyby Thursday, presumably scotching long-held hopes for a dramatic sky show on Earth over the next few weeks.
Or maybe not.
Well after many casual observers had given up on the comet's survival, updated pictures from the Solar and Heliospheric Observatory spacecraft -- SOHO -- showed what appeared to be a long trail of dust extending away from the sun along ISON's trajectory, brightening sharply toward its tip.Whether it was just a dust trail, or perhaps dust and larger fragments of ISON -- or both -- was not immediately clear. As several observers tweeted and re-tweeted: "It is now clear that Comet #ISON either survived or did not survive, or... maybe both. Hope that clarifies things."
Matthew Knight, an astronomer at the Lowell Observatory in Flagstaff, Az, said in a telephone interview that it wasn't clear exactly what SOHO was observing.
"Initially when something came out (after close approach), we thought this is just the dust trail and there's not much left, it's just going to fade away," he said. "And then images keep coming in and ... the last few, it seems pretty definitely like it's getting brighter. So we do not have a good answer as to what's going on.
"My best guess right now, and it's really only an educated guess, is that there is something left, probably smaller fragments, because it still doesn't look like there's a nuclear condensation. Inbound, the leading edge was brighter. It doesn't look like that. It just looks to me like there are some smaller fragments that may just actually be disintegrating. They just took longer to do it."
But it's also possible, he said, there could be "still a substantial nucleus there and it's actually outgassing. ... But I don't have any explanation for it if there's just nothing left."
Monitored by a fleet of space telescopes, ISON, an ancient remnant of the solar system's birth, made its close approach to the sun just after 1:25 p.m. EST, streaking by at more than 200 miles per second at an altitude of less than a million miles -- an exceedingly close shave by astronomical standards.
Astronomers around the world were on the edges of their seats as the comet approached the sun, many of them convinced the three-quarter-mile-wide snowball would break up due to the blistering heat of the encounter and the tidal stresses imposed by the sun's gravitational grip.
The comet appeared to fade and smear out as it closed in on the sun and astronomers monitoring instruments aboard two sun-watching spacecraft reported they were unable to immediately spot any traces of ISON after perihelion, its point of closest approach.
"In the case of Comet ISON, it appears to have disappeared and broken up into small enough chunks that over the course of hours, or a day or so, that those chunks have all evaporated," said Dean Pesnell, project scientist with NASA's Solar Dynamics Observatory spacecraft.
"And once it gets small enough and sees the sun's magnetic field ... (the fragments) don't stay together and we don't get to see them."
Karl Battams, a comet scientist with the U.S. Naval Research Laboratory, agreed, saying ISON "probably hasn't survived this journey."
Studying an image from a coronagraph aboard the Solar and Heliospheric Observatory spacecraft, Battams said he saw no sign of ISON emerging from behind the instrument's occulting disk, used to block out the glare of the sun, "and that, I think, could be the nail in the coffin."
Asked whether the comet might still make an appearance in Earth's sky as the presumed remnants move back out into deep space over the next few weeks, Pesnell said "probably not," adding that "if we don't see it coming out from behind ... the chances of it being bright enough as it moves away from the sun are fairly small."
Later in the day, spacecraft images showed what appeared to be a trail of dusty debris along the comet's path, but there was no sign of a nucleus or any large fragments.
"It looks like it disappeared completely," Pesnell said in a telephone interview. "You see some dust continuing around the orbit, but that could just be large dust particles that haven't yet evaporated. But there appears to be no source of dust."
Based on initial observations with the SDO spacecraft, Pesnell believes ISON must have broken up and evaporated before it reach the sun.
"If it had done that near the sun, we would have seen it," he said. "We see oxygen and pretty much every molecule has some oxygen in it. We should have seen oxygen. The fact that we didn't see it means that it must have evaporated before it got to where we could see it."
In the meantime, he added, "we do now have a conundrum -- how do we take a half-mile wide comet and turn it into nothing? Where did that go? And I think over the next couple of months we'll figure that out."
But later in the evening, updated pictures from SOHO led many to wonder if a large fragment of ISON had managed to survive its brush with the sun. The pictures clearly showed the dust left in the wake of the comet as it approached the sun, and extending on beyond it to a brighter point.
Whether that was a remnant of the comet, or just a cloud of dusty debris left in ISON's wake, was not immediately clear.
"It's been an emotional roller coaster," Knight said.
Going into the encounter, astronomers said there were three possibilities. The most favorable, if least likely: the comet could survive the encounter in one piece and perhaps live up to its billing as "comet of the century," developing a long tail that would grace northern hemisphere skies over the next few weeks.
More likely, they said, the comet would fracture and break apart. In that case, there were two scenarios. In one, the fragments would remain "active" as the sun's heat boiled away ice and dusty debris, still producing a visible tail visible on Earth. Comet Lovejoy suffered a similar fate last year and still put on a dramatic show for viewers in the southern hemisphere.
But given how close ISON came to the sun, they said there was a good chance the comet would break up and be completely consumed in the glare of the star, leaving burned-out cinders -- or nothing at all -- in its wake to disappoint comet enthusiasts around the world.
And that may be what happened Thursday.
"Breaking up is hard to do. Like Icarus, #comet #ISON may have flown too close to the sun," NASA tweeted. "We will continue to learn."
Comets are believed to be frozen relics left over from the solar system's birth, made up of materials in the original cloud of dusty debris that came together 4.5 billion years ago to form the sun, its retinue of planets and the asteroids now orbiting between Mars and Jupiter.
A sphere of icy debris known as the Oort Cloud extends from the outermost planets halfway to the nearest star. The most distant objects are barely held by the sun's gravity and an occasional disturbance -- a passing star, for example, or perhaps an unusual planetary alignment -- can alter orbits and cause an object to fall into the inner solar system.
Several million years ago, long before humans ever looked up at the night sky in wonder, Comet ISON was nudged onto a different trajectory, beginning the long fall toward the sun.
Unlike some comets, which make repeated trips around the sun in long, elliptical orbits, ISON was making its first visit and thus represented a pristine sample of the original solar nebula that coalesced to form the solar system.
ISON was discovered by two Russian astronomers in September 2012, early enough to give astronomers time to plan a coordinated global observing campaign using a battery of ground- and space-based telescopes, including the Hubble Space Telescope, the Chandra X-ray Observatory, a Mars orbiter and even the MESSENGER spacecraft orbiting Mercury.
Close in to the sun, a fleet of solar observatories focused on ISON, including the Solar and Heliospheric Observatory, or SOHO, NASA's Solar Dynamics Observatory, and the twin STEREO spacecraft.
In a SOHO coronagraph view, the comet could be seen on final approach, racing toward perihelion but appearing to fade somewhat in the final stages. Astronomers said comets in such images typically show up as bright pinpoints at the head of the tail, but no such pinpoints were visible in the imagery.
The SDO spacecraft was re-aimed to target the limb of the sun where ISON was expected to pass. But no signs of the comet were immediately seen.Did Comet ISON survive? Scientists see tiny hopeAssociated PressScientists were studying spacecraft images Friday to find out whether a small part of Comet ISON survived its close encounter with the sun.The comet at first seemed to have fallen apart as it approached the sun's sizzling surface, but new images showed a streak of light moving away from the sun that some said could indicate it wasn't game over just yet."It certainly appears as if there is an object there that is emitting material," said Alan Fitzsimmons, an astronomer at Queens University in Belfast, Northern Ireland.The European Space Agency, which had declared ISON's death on Twitter late Thursday, was backtracking early Friday, saying the comet "continues to surprise."Comet ISON, essentially a dirty snowball from the fringes of the solar system, was first spotted by a Russian telescope in September last year.Some sky gazers speculated early on that it might become the comet of the century because of its brightness, although expectations dimmed over time.The comet was two-thirds of a mile wide as it got within 1 million miles (1.6 million kilometers) of the sun, which in space terms basically means grazing it.NASA solar physicist Alex Young said Thursday the comet had been expected to show up in images from the Solar Dynamics Observatory spacecraft at around noon eastern time (1700 GMT), but almost four hours later there was "no sign of it whatsoever."Images from other spacecraft showed a light streak continuing past the sun, but Young said that was most likely a trail of dust continuing in the comet's trajectory.However, instead of fading, that trail appeared to get brighter Friday, suggesting that "at least some small fraction of ISON has remained in one piece," U.S. Navy solar researcher Karl Battams wrote on his blog. He cautioned that even if there is a solid nucleus, it may not survive for long.Two years ago, a smaller comet, Lovejoy, grazed the sun and survived, but fell apart a couple of days later.ISON's mysterious dance with the sun left astronomers puzzled and excited at the same time."This is what makes science interesting," said Fitzsimmons, who specializes in comets and asteroids. "If we knew what was going to happen, it wouldn't be interesting."ENDMore detailed space news can be found at:-----No virus found in this message.Checked by AVG - www.avg.comVersion: 2014.0.4158 / Virus Database: 3629/6848 - Release Date: 11/19/13Internal Virus Database is out of date.
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