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History > 2009 > USA > Space (II)




NGC 6302

Butterfly Emerges from Stellar Demise in Planetary Nebula NGC 6302

This celestial object looks like a delicate butterfly. But it is far from serene.

What resemble dainty butterfly wings

are actually roiling cauldrons of gas
heated to more than 36,000 degrees Fahrenheit.
The gas is tearing across space at more than 600,000 miles an hour
-- fast enough to travel from Earth to the moon in 24 minutes!

A dying star that was once
about five times the mass of the Sun is at the center of this fury.
It has ejected its envelope of gases and is now unleashing
a stream of ultraviolet radiation that is making the cast-off material glow.
This object is an example of a planetary nebula,
so-named because many of them have a round appearance
resembling that of a planet when viewed through a small telescope.

The Wide Field Camera 3 (WFC3),
a new camera aboard NASA’s Hubble Space Telescope,
snapped this image of the planetary nebula, catalogued as NGC 6302,
but more popularly called the Bug Nebula or the Butterfly Nebula.
WFC3 was installed by NASA astronauts in May 2009,
during the servicing mission to upgrade and repair the 19-year-old Hubble telescope.

NGC 6302 lies within our Milky Way galaxy,
roughly 3,800 light-years away in the constellation Scorpius.
The glowing gas is the star’s outer layers, expelled over about 2,200 years.
The "butterfly" stretches for more than two light-years,
which is about half the distance from the Sun to the nearest star, Alpha Centauri.

The central star itself cannot be seen,
because it is hidden within a doughnut-shaped ring of dust,
which appears as a dark band pinching the nebula in the center.
The thick dust belt constricts the star’s outflow,
creating the classic "bipolar" or hourglass shape
displayed by some planetary nebulae.

The star’s surface temperature
is estimated to be about 400,000 degrees Fahrenheit,
making it one of the hottest known stars in our galaxy.
Spectroscopic observations made with ground-based telescopes
show that the gas is roughly 36,000 degrees Fahrenheit,
which is unusually hot compared to a typical planetary nebulae.

The WFC3 image reveals a complex history of ejections from the star.
The star first evolved into a huge red-giant star,
with a diameter of about 1,000 times that of our Sun.
It then lost its extended outer layers.

Some of this gas was cast off from its equator at a relatively slow speed,
perhaps as low as 20,000 miles an hour, creating the doughnut-shaped ring.
Other gas was ejected perpendicular to the ring at higher speeds,
producing the elongated "wings" of the butterfly-shaped structure.
Later, as the central star heated up, a much faster stellar wind,
a stream of charged particles travelling at more than 2 million miles an hour,
plowed through the existing wing-shaped structure, further modifying its shape.

The image also shows numerous finger-like projections pointing back to the star,
which may mark denser blobs in the outflow that have resisted the pressure from the stellar wind.

The nebula's outer edges are largely due to light emitted by nitrogen, which marks the coolest gas visible in the picture.
WFC3 is equipped with a wide variety of filters that isolate light emitted by various chemical elements,
allowing astronomers to infer properties of the nebular gas, such as its temperature, density, and composition.

The white-colored regions are areas where light is emitted by sulfur.
These are regions where fast-moving gas overtakes and collides with slow-moving gas that left the star at an earlier time,
producing shock waves in the gas (the bright white edges on the sides facing the central star).
The white blob with the crisp edge at upper right is an example of one of those shock waves.

NGC 6302 was imaged on July 27, 2009 with Hubble’s Wide Field Camera 3 in ultraviolet and visible light.
Filters that isolate emissions from oxygen, helium, hydrogen, nitrogen, and sulfur
from the planetary nebula were used to create this composite image.

These Hubble observations of the planetary nebula NGC 6302
are part of the Hubble Servicing Mission 4 Early Release Observations.

Credit: NASA, ESA, and the Hubble SM4 ERO Team

Images from Refurbished Hubble        2009















A Sultry World

Is Found Circling a Distant Star


December 17, 2009
The New York Times


Call it Sauna World.

Astronomers said Wednesday that they had discovered a planet composed mostly of water.

You would not want to live there. In addition to the heat — 400 degrees Fahrenheit on the ocean surface — the planet is probably cloaked in a crushingly dank and dark fog of superheated steam and other gases. But its discovery has encouraged a growing feeling among astronomers that they are on the verge of a breakthrough and getting closer to finding a planet something could live on.

“This probably is not habitable, but it didn’t miss the habitable zone by that much,” said David Charbonneau of the Harvard-Smithsonian Center for Astrophysics, who led the team that discovered the new planet and will reports its findings on Thursday in the journal Nature.

Geoffrey W. Marcy, a planet hunter from the University of California, Berkeley, wrote in an accompanying article in Nature that the new work provided “the most watertight evidence so far for a planet that is something like our own Earth, outside our solar system.”

Only 2.7 times the size of Earth and 6.6 times as massive, the new planet takes 38 hours to circle a dim red star, GJ 1214, in the constellation Ophiuchus — about 40 light-years from here. It is one of the lightest and smallest so-called extrasolar planets yet found, part of a growing class that are less than 10 times the mass of the Earth.

Dr. Charbonneau’s announcement capped a week in which the list of known planets, including these “super-Earths,” grew significantly.

An international team of astronomers using telescopes in Australia and Hawaii reported in one paper that they had found three planets, including a super-Earth, orbiting 61 Virginis, a star in the constellation Virgo that is almost a clone of the Sun. In a separate paper, they reported finding a planet somewhat larger than Jupiter at the star 23 Librae. It was the first time, they said, that a super-Earth had been found belonging to a star like the Sun; the other home stars have been dwarfs.

And in yet another paper, a subset of the same group reported finding a super-Earth and probably two bigger planets circling HD 1461, a star in Cetus.

Paul Butler of the Carnegie Institution of Washington, who was involved in all three papers, said astronomers thought that from one-third to one-half of all Sun-like stars harbor such super-Earths orbiting at scorching distances much closer than Mercury is to the Sun.

In the 15 years since the first extrasolar planet was found, more than 400 have been detected. The field is getting more intense as dedicated planet-hunting instruments like the Kepler satellite from the National Aeronautics and Space Administration, due to report a new batch next month, get into the game.

Alan P. Boss, a planetary theorist at the Carnegie Institution of Washington, said of the planet hunters, “Give them a couple more years and they’re going to knock your socks off.”

Dr. Charbonneau’s planet, only 1.3 million miles from its home star, is distinguished by its relative coolness. It bakes rather than roasts, a consequence of the dimness of GJ 1214, which puts out one three-hundredth the Sun’s energy. He and his colleagues had set out to search for planets around such stars, noting that they are more numerous and that it is easier to discern planets around them.

“There is no question,” Dr. Charbonneau wrote in an e-mail message, “that small stars provide us with the fastest track to looking for life outside the solar system.”

His planet-hunting equipment is a bank of eight telescopes called MEarth, pronounced “mirth,” on Mount Hopkins in Arizona. They are only 16 inches in diameter, no bigger than those that grace the backyard of many amateur astronomers. They monitor the light of 2,000 nearby stars, looking for the regular blips caused when a planets passes by, or transits.

In May, Zachory Berta, a first-year graduate student of Dr. Charbonneau’s, called the group’s attention to a series of blips in the Ophiuchus star that seemed to be happening every 1.6 days. If he was right, Mr. Berta said, the next transit would occur at 6 a.m. on May 13.

Dr. Charbonneau was in Washington later that day preparing for a State Department dinner when he got a group e-mail message that began: “We have a winner. Congrats Zach!”

From the drop in starlight, the astronomers could calculate the diameter of the Ophiuchus planet, known now as GJ 1214b. Then they used a sensitive spectrograph on a 3.6-meter telescope in Chile to measure its gravitational tug on the star, thus deriving the planet’s mass. Dr. Charbonneau and his colleagues, using those two numbers, could calculate the density of the planet.

It was only the second time the density of a super-Earth had been measured, offering a rare chance for comparative planetology. The first — CoRoT 7b, discovered last year by the European Corot satellite — turned out to be about as dense as the Earth, suggesting that it is mostly rock.

The new planet is slightly heavier but significantly larger than the earlier one, and it is only about one-third Earth’s density.

“What we probably have here is a water world,” said Dr. Charbonneau, explaining that there are three basic ingredients abundant enough to go into the recipe for a planet.

They are light gases like hydrogen and helium, rocks like iron and silicates and so-called volatile materials like water.

The best recipe for the new planet would be a world that is predominantly water, with small amounts of rock in a core tens of thousands of miles underwater, surrounded by a suffocating atmosphere. By comparison, Earth is 0.06 percent water.

Dr. Charbonneau said the weight of the new planet’s presumptive atmosphere that kept the water liquid rather than just boiling into space. If all such super-Earths have this type of atmosphere, he and his colleagues write in their paper, none of them is likely to harbor life. Astronomers would have to redouble their efforts to seek even smaller planets to find habitable environments.

Dr. Charbonneau acknowledged that a different recipe, with more rock and a very puffy atmosphere, would also fit the data. That is unlikely, he and other planet experts say, but the sauna world theory may be soon tested.

The planet is close enough to be studied directly by telescopes on or near Earth. Indeed, Dr. Charbonneau said his team had already applied for observing time on the Hubble Space Telescope.

“Our own TV signals,” he said, “have already passed this star.”

    A Sultry World Is Found Circling a Distant Star, NYT, 17.12.2009,






Shuttle Atlantis Leaves Space Station,

Headed Home


November 25, 2009
Filed at 4:56 a.m. ET
The New York Times


CAPE CANAVERAL, Fla. (AP) -- Atlantis and its seven astronauts have left the International Space Station.

The shuttle undocked early Wednesday morning, ending its one-week visit. Pilot Barry ''Butch'' Wilmore was at the controls.

Atlantis is now aiming for a Friday morning landing back at NASA's Florida spaceport.

Two of Atlantis' crew members are especially eager to get home.

Astronaut Nicole Stott has been in orbit since late August. She says she misses her husband and 7-year-old son, being in the sunshine -- and pizza.

NASA's new dad in space, Randolph Bresnik, wants to see his baby daughter as soon as possible after the shuttle lands. Abigail Mae Bresnik was born Saturday night in Houston, shortly after his first spacewalk.

    Shuttle Atlantis Leaves Space Station, Headed Home, NYT, 25.11.2009,






Shuttle to Haul 27,000 Pounds

of Spare Parts


November 16, 2009
The New York Times


The space shuttle has often been called a pickup truck to orbit, and the next flight of the shuttle Atlantis, scheduled to launch Monday afternoon, lives up to that description.

The Atlantis is lugging up to the International Space Station a cargo bay full of spare parts, including a couple of refurbished gyroscopes, pumps, tanks for ammonia and nitrogen and piece called the “trailing umbilical system reel assembly” for the railway system that moves the station’s robotic arm.

“These are the highest priority spare parts for station,” said Eve Stavros, the payload flow manager of Boeing, which built the American portions of the station. “This flight is really the first flight of the last series of flights to stage spare parts up there.”

The parts — 27,250 pounds in all — are crucial, especially as policy makers look to extend the life of the space station by five years to 2020. After the space shuttles are retired in about a year, the National Aeronautics and Space Administration will have no way to take up any big, heavy replacement pieces to the station.

The 11-day mission is commanded by Marine Col. Charles O. Hobaugh, and the pilot is Navy Captain Barry E. Wilmore. The other crew members are Marine Lt. Col. Randolph J. Bresnik, Navy Capt. Michael J. Foreman, Leland D. Melvin and Robert L. Satcher, Jr. The mission includes three spacewalks.

Nicole P. Stott, who has spent three months on the space station, will return to Earth with the Atlantis crew.

The Atlantis will also bring back part of a balky toilet system that recycles urine into drinkable water. NASA officials said the station has sufficient fresh water for now, and they hope to send replacement parts on a future shuttle flight.

After the Atlantis’s flight, only five shuttle flights remain on the schedule.

The countdown, which began Friday, has proceeded without glitches. “We’ve had a very clean countdown to date, and are currently on schedule with no problems to report,” Stephen J. Paine, a shuttle test director, said during a news conference Sunday morning.

Forecasts give a 90 percent of favorable weather for the 2:28 p.m. launching Monday from the Kennedy Space Center. The countdown has been so trouble-free that a reporter asked Mr. Paine if he thought the mission was jinxed.

“I’ll take any good luck we can get,” Mr. Paine replied, “and a smooth count is good to have every now and again.”

    Shuttle to Haul 27,000 Pounds of Spare Parts, NYT, 16.11.2009,






Setting Sail Into Space,

Propelled by Sunshine


November 10, 2009
The New York Times


Peter Pan would be so happy.

About a year from now, if all goes well, a box about the size of a loaf of bread will pop out of a rocket some 500 miles above the Earth. There in the vacuum it will unfurl four triangular sails as shiny as moonlight and only barely more substantial. Then it will slowly rise on a sunbeam and move across the stars.

LightSail-1, as it is dubbed, will not make it to Neverland. At best the device will sail a few hours and gain a few miles in altitude. But those hours will mark a milestone for a dream that is almost as old as the rocket age itself, and as romantic: to navigate the cosmos on winds of starlight the way sailors for thousands of years have navigated the ocean on the winds of the Earth.

“Sailing on light is the only technology that can someday take us to the stars,” said Louis Friedman, director of the Planetary Society, the worldwide organization of space enthusiasts.

Even as the National Aeronautics and Space Administration continues to flounder in a search for its future, Dr. Friedman announced Monday that the Planetary Society, with help from an anonymous donor, would be taking baby steps toward a future worthy of science fiction. Over the next three years, the society will build and fly a series of solar-sail spacecraft dubbed LightSails, first in orbit around the Earth and eventually into deeper space.

The voyages are an outgrowth of a long collaboration between the society and Cosmos Studios of Ithaca, N.Y., headed by Ann Druyan, a film producer and widow of the late astronomer and author Carl Sagan.

Sagan was a founder of the Planetary Society, in 1980, with Dr. Friedman and Bruce Murray, then director of the Jet Propulsion Laboratory. The announcement was made at the Hart Senate Office Building in Washington at a celebration of what would have been Sagan’s 75th birthday. He died in 1996.

Ms. Druyan, who has been chief fund-raiser for the society’s sailing projects, called the space sail “a Taj Mahal” for Sagan, who loved the notion and had embraced it as a symbol for the wise use of technology.

There is a long line of visionaries, stretching back to the Russian rocket pioneers Konstantin Tsiolkovsky and Fridrich Tsander and the author Arthur C. Clarke, who have supported this idea. “Sails are just a marvelous way of getting around the universe,” said Freeman Dyson, of the Institute for Advanced Study in Princeton, N.J., and a longtime student of the future, “but it takes a long time to imagine them becoming practical.”

The solar sail receives its driving force from the simple fact that light carries not just energy but also momentum — a story told by every comet tail, which consists of dust blown by sunlight from a comet’s core. The force on a solar sail is gentle, if not feeble, but unlike a rocket, which fires for a few minutes at most, it is constant. Over days and years a big enough sail, say a mile on a side, could reach speeds of hundreds of thousands of miles an hour, fast enough to traverse the solar system in 5 years. Riding the beam from a powerful laser, a sail could even make the journey to another star system in 100 years, that is to say, a human lifespan.

Whether humans could ever take these trips depends on just how starry-eyed one’s view of the future is.

Dr. Friedman said it would take too long and involve too much exposure to radiation to sail humans to a place like Mars. He said the only passengers on an interstellar voyage — even after 200 years of additional technological development — were likely to be robots or perhaps our genomes encoded on a chip, a consequence of the need to keep the craft light, like a giant cosmic kite.

In principle, a solar sail can do anything a regular sail can do, like tacking. Unlike other spacecraft, it can act as an antigravity machine, using solar pressure to balance the Sun’s gravity and thus hover anyplace in space.

And, of course, it does not have to carry tons of rocket fuel. As the writer and folk singer Jonathan Eberhart wrote in his song “A Solar Privateer”:

No cold LOX tanks or reactor banks, just Mylar by the mile.

No stormy blast to rattle the mast, a sober wind and true.

Just haul and tack and ball the jack like the waterlubbers do.

Those are visions for the long haul. “Think centuries or millennia, not decades,” said Dr. Dyson, who also said he approved of the Planetary Society project.

“We ought to be doing things that are romantic,” he said, adding that nobody knew yet how to build sails big and thin enough for serious travel. “You have to get equipment for unrolling them and stretching them — a big piece of engineering that’s not been done. But the joy of technology is that it’s unpredictable.”

At one time or another, many of NASA’s laboratories have studied solar sails. Scientists at the Jet Propulsion Laboratory even once investigated sending a solar sail to rendezvous and ride along with Halley’s Comet during its pass in 1986.

But efforts by the agency have dried up as it searches for dollars to keep the human spaceflight program going, said Donna Shirley, a retired J.P.L. engineer and former chairwoman of the NASA Institute for Advanced Concepts. Dr. Shirley said that the solar sail was feasible and that the only question was, “Do you want to spend some money?” Until the technology had been demonstrated, she said, no one would use it.

Japan continues to have a program, and test solar sails have been deployed from satellites or rockets, but no one has ever gotten as far as trying to sail them anywhere.

Dr. Friedman, who cut his teeth on the Halley’s Comet proposal, has long sought to weigh anchor in space. An effort by the Planetary Society and the Russian Academy of Sciences to launch a sail about 100 feet on a side, known as Cosmos-1, from a Russian missile submarine in June 2005 ended with what Ms. Druyan called “our beautiful spacecraft” at the bottom of the Barents Sea.

Ms. Druyan and Dr. Friedman were beating the bushes for money for a Cosmos-2, when NASA asked if the society wanted to take over a smaller project known as the Nanosail. These are only 18 feet on a side and designed to increase atmospheric drag and thus help satellites out of orbit.

And so LightSail was born. Its sail, adapted from the Nanosail project, is made of aluminized Mylar about one-quarter the thickness of a trash bag. The body of the spacecraft will consist of three miniature satellites known as CubeSats, four inches on a side, which were first developed by students at Stanford and now can be bought on the Web, among other places. One of the cubes will hold electronics and the other two will carry folded-up sails, Dr. Friedman said.

Assembled like blocks, the whole thing weighs less than five kilograms, or about 11 pounds. “The hardware is the smallest part,” Dr. Friedman said. “You can’t spend a lot on a five-kilogram system.”

The next break came when Dr. Friedman was talking about the LightSail to a group of potential donors. A man — “a very modest dear person,” in Ms. Druyan’s words — asked about the cost of the missions and then committed to paying for two of them, and perhaps a third, if all went well.

After the talk, the man, who does not wish his identity to be known, according to the society, came up and asked for the society’s bank routing number. Within days the money was in its bank account. The LightSail missions will be spread about a year apart, starting around the end of 2010, with the exact timing depending on what rockets are available. The idea, Dr. Friedman said, is to piggyback on the launching of a regular satellite. Various American and Russian rockets are all possibilities for a ride, he said.

Dr. Friedman said the first flight, LightSail-1, would be a success if the sail could be controlled for even a small part of an orbit and it showed any sign of being accelerated by sunlight. “For the first flight, anything measurable is great,” he said. In addition there will be an outrigger camera to capture what Ms. Druyan called “the Kitty Hawk moment.”

The next flight will feature a larger sail and will last several days, building up enough velocity to raise its orbit by tens or hundreds of miles, Dr. Friedman said.

For the third flight, Dr. Friedman and his colleagues intend to set sail out of Earth orbit with a package of scientific instruments to monitor the output of the Sun and provide early warning of magnetic storms that can disrupt power grids and even damage spacecraft. The plan is to set up camp at a point where the gravity of the Earth and Sun balance each other — called L1, about 900,000 miles from the Earth — a popular place for conventional scientific satellites. That, he acknowledges, will require a small rocket, like the attitude control jets on the shuttle, to move out of Earth orbit, perhaps frustrating to a purist.

But then again, most sailboats do have a motor for tooling around in the harbor, which is how Dr. Friedman describes being in Earth orbit. Because the direction of the Sun keeps changing, he said, you keep “tacking around in the harbor when what you want to do is get out on the ocean.”

The ocean, he said, awaits.

    Setting Sail Into Space, Propelled by Sunshine, NYT, 10.11.2009,






In Test of Water on Moon,

Craft Hits Bull’s-Eye


October 10, 2009
The New York Times


MOUNTAIN VIEW, Calif. — More than 230,000 miles from Earth, a NASA spacecraft hit a bull’s-eye on the Moon on Friday morning. Actually, two bull’s-eyes.

But at least the early images failed to show the expected plumes of debris rising out of the impacts.

At 4:31 a.m. Pacific time (7:31 a.m. Eastern time), one piece of the Lunar Crater Observation and Sensing Satellite — LCROSS, for short — slammed into the bottom of a crater at 5,600 miles per hour, excavating about 350 metric tons of the moon and leaving behind a hole about 65 feet wide, 13 feet deep.

Trailing four minutes behind, a second piece sent its observations back to Earth before it also slammed into the same crater.

Disappointingly, the live images sent back by the trailing spacecraft did not show the plume.

“It would have given us all an adrenaline rush this morning,” said David Morrison, director of the NASA Lunar Science Institute. Nonetheless, there was a wealth of other data taken by other instruments.

Many ground-based telescopes that had been pointed to that one crater at the bottom of the Moon also failed to spot the theatrics.

“As far as I can tell from our quick processing, we did not see any plume,” said William Keel, a professor of astronomy at the University of Alabama who was operating a telescope at the Kitt Peak National Observatory in Tucson, Ariz.

If the spacecraft hit a rocky area, the debris may not have been tossed as high and perhaps not even high enough to reach sunlight.

Of greatest interest is whether there is water ice hidden in the crater’s perpetual darkness and frigidness. The data could play into the debate over where NASA’s human spaceflight program should aim next, whether to return to the Moon or head elsewhere in the solar system neighborhood. The presence of large significant amounts of water could make it easier to set up future settlements with the ice providing water and oxygen.

Data from NASA’s Lunar Reconnaissance Orbiter has already confirmed the presence of hydrogen deep within permanently shadowed craters near the Moon’s poles, and hydrogen is most likely in the form of water.

“There is hydrogen down in that crater, and we’re going to go dig some of it up,” Anthony Colaprete, the mission’s principal investigator, said in a telephone news conference Thursday. A few days of data analysis will be needed to determine whether water was indeed present in any debris kicked up by the impact.

LCROSS is a $79 million companion mission to the Lunar Reconnaissance Orbiter, sharing the same rocket into space in June. The mission designers took advantage of what would have otherwise been space junk — the rocket’s 2.2-ton, second stage — and turned it into a projectile to hit the Moon, shepherded by a car-size spacecraft.

While the orbiter entered orbit around the Moon, LCROSS swung into a wide polar orbit around the Earth that, by design, would intersect with the Moon’s path four months later at 5,600 miles per hour, or twice the speed of a speeding bullet.

The target of LCROSS is Cabeus crater, about 60 miles wide near the south pole.

At 6:50 p.m. Pacific time Thursday, the LCROSS spacecraft separated from the expended second stage and, 40 minutes later, fired thrusters to slow slightly and drop behind. While LCROSS itself had the best view of the first impact, sending back live television images, a host of telescopes in space and on Earth, including the Hubble Space Telescope and the Keck telescope in Hawaii, were gazing at the Moon. The other telescopes also saw the second impact of the spacecraft.

Several hundred people spent a chilly night on a grassy lawn at NASA’s Ames Research Center here, where the mission is being run. Some pitched tents to spend the night. Others wrapped themselves in sleeping bags and Google-contributed mylar blankets as they listened to Charlie Duke, one of the Apollo 16 astronauts, and then watched three space-themed films — “Fly Me to the Moon,” “The Dish” and “October Sky” — projected on a big screen.

Then they watched the same NASA coverage of the mission, streamed over the Internet, that they could have watched at home.

“It’s adventurous and nerdy at the same time,” said Karin Atkins of Sunnyvale, Calif., one of those pulling an outdoors all-nighter.

Nine-year-old Alberto Rodriguez of Redwood City, Calif., had asked his mother if he could go to the all-night NASA event, and at around 10 p.m., his mother woke him up and took him to Ames.

“I just wanted to see the real thing,” said Alberto, who said he wants to become an astronaut and head to the Moon and Mars. “This is history. Just like the lunar landing.”

    In Test of Water on Moon, Craft Hits Bull’s-Eye, NYT, 10.10.2009,






Shuttle Glides to a California Landing


September 12, 2009
The New York Times


The shuttle Discovery glided to a day-late Mojave Desert touchdown Friday, leaving a fresh crew member and nine tons of equipment and supplies behind aboard the International Space Station.

Bringing another astronaut home after two months in space, the shuttle settled to a flawless landing on Runway 22 at Edwards Air Force Base just north of Los Angeles to close out a successful two-week resupply mission.

The astronauts had hoped to land at the Kennedy Space Center in Florida, but showers and thunderstorms blocked two efforts on Thursday and two more Friday. With an equally poor forecast for Saturday, the entry flight director, Richard Jones, diverted the Discovery to Edwards.

Flying upside down and backward over the southern Indian Ocean, Col. Frederick W. Sturckow of the Marines, the commander, and Kevin A. Ford, the pilot and a retired Air Force colonel, fired the shuttle’s twin braking rockets at 7:47 p.m. Eastern time to begin the hourlong descent.

Approaching from the southwest, Colonel Sturckow monitored a steep computer-controlled descent across the Los Angeles Basin before taking manual control 50,000 feet above the Mojave Desert and guiding the shuttle to a crisp landing at 8:53 p.m.

“Houston, Discovery, wheels stopped,” he radioed when the shuttle coasted to a halt.

“Welcome home, Discovery. Congratulations on an extremely successful mission, stepping up science to a new level on the International Space Station,” Col. Eric A. Boe of the Air Force replied from mission control in Houston.

Colonel Sturckow, Mr. Ford and the other astronauts — José M. Hernández; John D. Olivas; Col. Patrick G. Forrester of the Army, retired; Christer Fuglesang of Sweden; and Col. Timothy L. Kopra of the Army — planned to fly back to Houston on Saturday for reunions with friends and family members.

Colonel Kopra made the trip back to Earth resting on his back in a recumbent seat to ease his return to gravity after 58 days in space. Flight surgeons were standing by to assist and collect medical data on his re-adaptation.

“This experience has completely exceeded anything that I thought it would be like, just the sights, the sounds, the experiences with a great crew,” Colonel Kopra said last week, adding that the main thing he was looking forward to was “seeing my family again, my wife and two kids — and maybe have a sip of a beer.”

Nicole P. Stott replaced Colonel Kopra on the space station and is to remain there until the next shuttle visit, in November.

Colonel Sturckow and his crewmates delivered nine tons of equipment and supplies to the station, including two experiment racks, a sample freezer, a second treadmill, a crew sleep station and a carbon dioxide removal system.

During three spacewalks, they also installed a new 1,800-pound ammonia coolant tank, deployed a cargo attachment mechanism, retrieved two external experiments and made preparations for attachment of a new module next year.

    Shuttle Glides to a California Landing, NYT, 12.9.2009,






After Hubble Repair,

New Images From Space


September 10, 2009
The New York Times


The cosmic postcards are back.

Astronomers on Wednesday unveiled new pictures and observations from the Hubble Space Telescope. With the exception of a picture last month of the bruise on Jupiter caused by a comet, they were the first data obtained with the telescope since a crew spent 13 days in orbit last May replacing, refurbishing and rebuilding its vital components.

“This is truly Hubble’s new beginning,” Edward Weiler, the associate administrator for science at the National Aeronautics and Space Administration, said at a news conference in Washington.

The event, which included Senator Barbara A. Mikulski, Democrat of Maryland, and the NASA administrator, Maj. Gen. Charles F. Bolden Jr., who is retired from the Marine Corps, was a mix of science and celebration of the human spirit and innovation.

“I’m in awe of the human ingenuity that could conceive of such a thing and then make it happen,” said K. Megan McArthur, an astronaut who flew on the repair mission last spring

Heidi Hammel of the Space Science Institute in Boulder, Colo., said, “We’re giddy with the quality of the data we’re getting.”

Among the images were gas flying from a dying star that looked like a butterfly spreading its wings, and a galaxy nearly 10 billion light-years away whose image had been stretched and magnified by the gravity of a cluster of galaxies into a “dragon” shape. Examining such images, astronomers can study details of galaxies that existed before the Milky Way was born and chart the distribution of mysterious dark matter in the universe.

Dr. Weiler noted that the telescope was now in the best shape of its 19-year life in orbit, far surpassing the ambitions of its founders, and that it could last for at least another five years.

“Hubble gets better and better and better,” he said.

The telescope has had almost as many reincarnations as a cat. It was born in a vision of Lyman Spitzer, a Princeton astronomer who realized in 1946 that a telescope in space above the blurring effects of the atmosphere could make more precise measurements of stars, as well as see infrared and ultraviolet radiation that cannot make it through air.

Launched with great fanfare from the space shuttle in 1990, the telescope became a national joke when it was discovered that its primary mirror had been painstakingly polished to the wrong shape.

The mistake was so simple, however, that it could be repaired. In 1993, an astronaut crew installed corrective optics on the telescope, and the heavens snapped into focus. Astronauts have visited the telescope four more times in a series of increasingly ambitious servicing missions, and the telescope became increasingly powerful.

By the time of the final servicing mission, only one of the telescope’s three cameras was working and its spectrograph had shut down. In May, a crew from the shuttle Atlantis installed a new camera and spectrograph and repaired the other spectrograph and the telescope’s prime camera, the Advanced Camera for Surveys, among other tasks.

The job was almost a complete success. The exception was that the astronauts were unable to restore a high-resolution capability on the survey camera. It is mostly used in a wide-field mode, astronomers say, but one of the more exciting Hubble pictures recently was a high-resolution image of a planet orbiting the star Fomalhaut obtained by Paul G. Kalas of the University of California, Berkeley, and his colleagues.

At the news conference, David S. Leckrone, longtime Hubble senior scientist, announced that another of the telescope’s instruments, an infrared camera known as Nicmos that had been dormant but that had not been worked on by the astronauts, was now back.

Dr. Leckrone said he was proud to report that there were no problems with the spacecraft.

“Somehow,” he said, addressing the entire NASA and astronomical community, “you guys managed to pull it off.”

Dr. Weiler, the NASA associate administrator, thanked the 32 astronauts “who have risked their lives flying up to Hubble and keeping the scientists happy.”

Asked their reactions to seeing the new pictures, most of the astronauts who were on the mission in May said some version of “wow.” Michael J. Massimino, who performed two spacewalks then, said, “Thank God we didn’t break it.”

After Hubble Repair, New Images From Space,