Missing ‘Big Bang’ Antarctic Telescope Found

University of Minnesota faculty and students pose in front of a telescope that, for a nerve-wracking couple of days, went missing aboard a truck while it was being delivered to the NASA-run Columbia Scientific Balloon Facility in Palestine, Texas. The picture was taken in 2009 at Fort Sumner, New Mexico. (Courtesy Shaul Hanany, University of Minnesota)

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Astronomers and students from the University of Minnesota hoping to search for radiation left over from the Big Bang instead spent the past few days looking for their telescope – a 6,000 lb (2729 kg) behemoth of a science experiment. Just how does a telescope that big go missing? You could ask the truck driver who was supposed to deliver it to a NASA facility in Palestine, Texas, but he’s not talking and police in Texas won’t press charges against him. But the good news is that the missing telescope has been found – sitting at a truck wash — after a frantic cross-country search.

The telescope is a high-tech irreplaceable piece of equipment that is 22 ft high 15 ft wide (6.5 X 4.5 meters). It is designed to detect radiation from the Big Bang and it took fifteen people 8 years to build. The telescope will be shipped to Antarctica, where it will be attached to a giant balloon in December and sent 110,000 feet (33,500 meters) into the atmosphere.

Last Friday, a Minnesota trucking company sent off one of their trucks with telescope inside. But by Monday there was no word from the trucker and the scientists started to panic when the truck didn’t show up at the NASA facility. Calls to the trucker went unanswered. The owner of the trucking company sent his son to Dallas to search for the truck and the driver. Their only clue was a credit card charge at a Dallas truck stop.

The son found the driver, asleep in the cab of the truck, but the trailer, with the precious cargo inside, was nowhere to be seen.

The driver said he left the trailer at a hotel parking lot, but when the searchers arrived, it wasn’t there. More searching, and the trucker clammed up and wouldn’t provide any more clues or reasons for why he didn’t deliver his cargo.

Finally another employee of the trucking company found the trailer sitting at a truck wash in Dallas.

“If they would not have found that particular trailer at that time, maybe half a day or a day later someone would have stolen it and taken it for metal or just for scrap,” said physics professor Shaul Hanany, the project’s lead researcher.

NASA unpacked the crate Thursday morning and said the telescope was unharmed and is in great shape.

The owner of the trucking company said sometimes they do have trouble with drivers, but he has never had anything like this happen, especially with such a unique instrument. He wondered, why couldn’t the driver be hauling a load of potato chips instead of something that will solve the mysteries of the Universe?

The driver has been fired, and the telescope will head to Antarctica as planned.

Source: Minnesota Public Radio

Help Astronomers Collect Venus Transit Data!

In the Rapa Nui language, Hetu'u means stars. Image Credit: David Rodriguez (Universidad de Chile).

[/caption]During June 5th/6th 2012, Venus will be transiting the Sun, where it will make a rare appearance as a small dot moving across the face of the Sun. Astronomers around the world are planning observations, and one team is traveling to Easter Island in an attempt to reproduce the measurements first made/proposed by Edmund Halley in the late 1600’s, getting precise data of first contact between Venus and the Sun. They are working with students from around the world and are looking for help to connect with more students to participate in the event.

The team is asking for assistance from astronomy clubs and organizations, especially those who work with school children. Since the team will be observing on Easter Island, their view of the transit will be limited (it begins two hours before sunset). Since the team will only be measuring the time of ingress and not egress, the team is reaching out to additional observers to help collect data. So far, the team has colleagues in Hawaii, New York, Australia, Iran, and Holland who will be assisting with their efforts.

Keep reading to learn how your club (or school group) can help collect transit data!

Dr. Jacqueline Faherty states, “As part of the celebration, we are networking multiple school groups around the world that are also viewing the transit so we can make a measurement of the distance to the Sun, combining timing measurements of first and last contact from various points on the Earth.” Faherty also adds, “This is not about making an accurate measurement but rather an attempt to inspire young students, our next generation of scientists, when they see that astronomical phenomena (while rare) can be used to make real and extremely useful measurements while at the same time connecting a network of students from different countries, cultures, political histories, etc.”

To participate you only need do the following:

  • At the time of the transit have a calibrated clock (GPS clock preferred but not necessary)
  • From your location we need the time of ingress or egress interior (exterior as well if you can do it). This is the time that Venus has passed into the interior of the Sun. See this webpage for an estimated time of when you can expect the events to occur for your location: http://transitofvenus.nl/wp/where-when/local-transit-times/
  • As a secondary measurement of the transit we are also going to try to match images taken of the transit from different positions on Earth. If you will be photographing the event please try to capture an image exactly (or close to exactly) on the 10’s of each hour. We will coordinate the rest.
  • Be sure to take a photograph of you and your students watching/measuring/enjoying the transit
  • Email Dr. Faherty ([email protected]) saying that you are interested in participating in our group so we can add you to our global network and map: http://www.das.uchile.cl/~drodrigu/easter/transit.html
  • Once again the team is especially interested in school groups that will be viewing the transit. The team hopes to inspire the next generation of scientists, by demonstrating how astronomical phenomenon can be used for scientific purposes. The team will feature photos from participating groups and the results of their measurements in a blog series hosted by the American Museum of Natural History.

    For more information on the team, visit their website at: http://www.das.uchile.cl/~drodrigu/easter/index_en.html

    If you’d like to see the math behind the measurements, visit David Rodriguez’s blog: http://strakul.blogspot.com/2012/05/measuring-distance-to-sun-with-transit.html

    Visibility information for the transit of Venus can be found at: http://eclipse.gsfc.nasa.gov/OH/transit12.html.

    Source: Dr. Catherine Kaleida, Dr. Jacqueline Faherty, and the 2012 Transit of Venus Easter Island Public Outreach Team

    Was Pluto Ever REALLY a Planet?

    Pluto, Charon, Nix and Hydra (NASA)

    Ever since the infamous 2006 reclassification of Pluto off the list of “official” planets (which had a rather incendiary effect on many of the distant world’s Earthly fans) the term “planet” has been seen by some as a variable one, difficult to define and apparently able to be given and taken away. But was Pluto ever really deserving of the title to begin with?

    This fun info-animation by C.G.P. Grey suggests that it wasn’t, and offers a compelling explanation why.

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    Grey writes on his blog:

    “To my constant surprise the issue of Pluto’s planetary status — which I think should be a dry technical issue — really gets people riled. But it’s also been my experience that the people who most want Pluto to be a planet know the least about it and the history of its discovery. So, I hope that this video can help correct that a little bit.”

    We still love you, Pluto, no matter what you are!

    See more of Grey’s excellent animations on YouTube here.

    Timelapse of a Moonrise as Seen from the ISS

    Astronaut Don Pettit continues to ‘wow’ us all with his photographic exploits. In this great timelapse video, not only does Pettit capture a stunning Moonrise over Earth, but he had the presence of mind to set up his video camera in such way that he could also show himself opening the shutters in the space station’s Cupola observation windows just in time to watch all the action. The time-lapse scene was photographed from the airlock of the ISS’s Russian segment.

    Stunning Visualization of 56 Years of Tornadoes in the US

    The tracks of tornadoes in the US during the past 56 years, categorized by F-Scale. Credit: John Nelson

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    It’s a wonder of nature, baby. Using information from data.gov, tech blogger John Nelson has created this spectacular image of tornado paths in the US over a 56 year period. The graphic categorizes the storms by F-scale with the brighter neon lines representing more violent storms.

    Makes you want to hang on to something solid.

    Nelson also provided some stats on all the storms in the different categories:

    The numbers represent total deaths, total injuries, average miles the storms traveled
    F0: 7, 267, 2
    F1: 111, 3270, 6.58
    F2: 363, 10373, 11.4
    F3: 958, 18160, 17.80
    F4: 1912, 28427, 28.62
    F5: 1013, 11038, 38.87

    This provides a new appreciation for the term “suck zone” used in the movie “Twister.

    While tornadoes don’t travel in straight lines, Nelson explains that based on the data, the vectors were created using touchdown points and liftoff points.

    Nelson said he got the data from this Data.gov page doing a “tornado tracks” search.

    See Nelson’s original post.

    It’s Inevitable: Milky Way, Andromeda Galaxy Heading for Collision

    This illustration shows a stage in the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. In this image, representing Earth's night sky in 3.75 billion years, Andromeda (left) fills the field of view and begins to distort the Milky Way with tidal pull. (Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger)

    Astronomers have known for years that our Milky Way and its closest neighbor, the Andromeda galaxy, (a.k.a M31) are being pulled together in a gravitational dance, but no one was sure whether the galaxies would collide head-on or glide past one another. Precise measurements from the Hubble Space Telescope have now confirmed that the two galaxies are indeed on a collision course, headed straight for a colossal cosmic collision.

    No need to panic for the moment, as this is not going to happen for another four billion years. And while astronomers say it is likely the Sun will be flung into a different region of our galaxy, Earth and the solar system will probably just go along for the ride and are in no danger of being destroyed.

    “In the ‘worst-case-scenario’ simulation, M31 slams into the Milky Way head-on and the stars are all scattered into different orbits,” said team member Gurtina Besla of Columbia University in New York, N.Y. “The stellar populations of both galaxies are jostled, and the Milky Way loses its flattened pancake shape with most of the stars on nearly circular orbits. The galaxies’ cores merge, and the stars settle into randomized orbits to create an elliptical-shaped galaxy.”

    The simulations Besla was talking about came from precise measurements by Hubble, painstakingly determining the motion of Andromeda, looking particularly at the sideways motion of M31, which until now has not been able to be done.

    “This was accomplished by repeatedly observing select regions of the galaxy over a five- to seven-year period,” said Jay Anderson of STScI.

    Right now, M31 is 2.5 million light-years away, but it is inexorably falling toward the Milky Way under the mutual pull of gravity between the two galaxies and the invisible dark matter that surrounds them both.

    Of course, the collision is not like a head-on between two cars that takes place in an instant. Hubble data show that it will take an additional two billion years after the encounter for the interacting galaxies to completely merge under the tug of gravity and reshape into a single elliptical galaxy similar to the kind commonly seen in the local universe.

    Astronomers said the stars inside each galaxy are so far apart that they will not collide with other stars during the encounter. However, the stars will be thrown into different orbits around the new galactic center. Simulations show that our solar system will probably be tossed much farther from the galactic core than it is today.

    There’s also the complication of M31’s small companion, the Triangulum galaxy, M33. This galaxy will join in the collision and perhaps later merge with the M31/Milky Way pair. There is a small chance that M33 will hit the Milky Way first.

    The astronomers working on this project said that they were able to make the precise measurements because of the upgraded cameras on Hubble, installed during the final servicing mission. This gave astronomers a long enough time baseline to make the critical measurements needed to nail down M31’s motion.

    The Hubble observations and the consequences of the merger are reported in three papers that will appear in an upcoming issue of the Astrophysical Journal.

    This series of photo illustrations shows the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy. Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas, and A. Mellinger

    First Row, Left: Present day.
    First Row, Right: In 2 billion years the disk of the approaching Andromeda galaxy is noticeably larger.
    Second Row, Left: In 3.75 billion years Andromeda fills the field of view.
    Second Row, Right: In 3.85 billion years the sky is ablaze with new star formation.
    Third Row, Left: In 3.9 billion years, star formation continues.
    Third Row, Right: In 4 billion years Andromeda is tidally stretched and the Milky Way becomes warped.
    Fourth Row, Left: In 5.1 billion years the cores of the Milky Way and Andromeda appear as a pair of bright lobes.
    Fourth Row, Right: In 7 billion years the merged galaxies form a huge elliptical galaxy, its bright core dominating the nighttime sky.

    Source: HubbleSite See more images and videos here and here.

    Dragon’s Ocean Splashdown Caps Historic Opening of New Space Era

    1st picture of the Dragon spacecraft as it floats in the ocean awaiting recovery ships. Dragon splashed down successfully on May 31, 2012 at 11:42 a.m. EDT in the Pacific Ocean off the west coast of California. In a carefully timed sequence of events, dual drogue parachutes deploy at 45,000 feet to stabilize and slow the spacecraft. Full deployment of the drogues triggers the release of the main parachutes, each 116 feet in diameter, at about 10,000 feet, with the drogues detaching from the spacecraft. Main parachutes further slow the spacecraft's descent to approximately 16 to 18 feet per second. Credit: Michael Altenhofen

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    Concluding a perfectly executed and history making test flight, the first private spacecraft ever to visit and dock at the International Space Station (ISS) performed a picture perfect splashdown at 11:42 a.m. EDT (1542 GMT) today, May 31, in the Pacific Ocean, off the west coast of Baja, California, some 560 miles southwest of Los Angeles to cap the opening to a historic new Era in Space Exploration.

    Dragon is the linchpin in NASA’s bold Commercial Crew and Cargo program aimed at significantly driving down the cost of transporting cargo and crews to low Earth orbit by using private commercial companies to foster competition and innovation in the free market setting of the new, post-shuttle Era of Commercial Space Transportation.

    NASA aircraft were able to transmit live video of the last few minutes of the Dragon’s breathtaking descent, unfurling of the trio of parachutes and ocean splashdown – pretty much on target at 27 degrees latitude and 127 degrees west longitude.

    The official mission elapsed time on landing was 9 days, 7 hours and 58 minutes.

    Splashdown of the Dragon cargo craft took place barely 6 hours after departing the orbiting lab complex following detachment from the station using the station robotic arm. The ISS astronauts released the craft from the grip of the station’s robot arm at 5:49 a.m. EST (949 GMT) this morning, May 31.

    Screen shot of Dragon after May 31 splashdown in the Pacific Ocean. Credit: NASA TV

    The two spacecraft were soaring some 250 miles (400 km) high above the Indian Ocean east of Africa at the moment of release and departure. Altogether, Dragon spent 5 days, 16 hours and 5 minutes mated to the station.

    The gumdrop shaped Dragon capsule is 4.4 meters (14.4 ft) tall, and 3.66 m (12 ft) in diameter and has an internal pressurized volume of about 350 cubic feet .

    The Dragon cargo resupply capsule was built by SpaceX and is being retrieved from the ocean by a flotilla of three recovery ships. The ships reached Dragon, detached the chutes and are in the process of recovery. It will take about two days to deliver the craft to the port of Los Angeles where the most critical cargo items will be removed for quick shipment to NASA. The capsule will then be shipped to SpaceX’s McGregor,Texas facility for post-flight evaluation.

    Dragon is the world’s first commercial spacecraft whose purpose is to carry supplies to and from the ISS and partially replace the cargo capabilities previously performed by NASA’s now retired fleet of space shuttle orbiters. Dragon was designed, developed and built by Hawthorne, Calif., based SpaceX Corporation, founded in 2002 by CEO and Chief Designer Elon Musk.

    “This has been a fantastic day,” said Musk at a post splashdown briefing for reporters. “I want to thank NASA and the whole SpaceX team for an amazing job.”

    “I’m really proud of everyone. This really couldn’t have gone better. We’re looking forward to doing lots more missions in the future and continuing to upgrade the technology and push the frontier of space transportation.”

    “In baseball terminology this would be a grand slam. I am overwhelmed with joy.”

    The de-orbit burn to drop Dragon out of orbit took place precisely on time at 10:51 a.m. EDT for a change in velocity of 100 m/sec about 246 miles above the Indian Ocean directly to the south of India as the craft was some 200 miles in front of the ISS.

    Screen shot of Dragon after May 31 splashdown in the Pacific Ocean. Credit: NASA TV

    The Draco thruster firing lasted 9 minutes and 50 seconds and sent Dragon plummeting through the Earth’s atmosphere where it had to survive extreme temperatures exceeding 3000 degrees F (1600 degrees C) before landing.

    The Dragon capsule is the first US vehicle of any kind to arrive at the ISS since the July 2011 forced retirement of NASA’s Space Shuttle Program resulted in the total loss of all US capability to send cargo and humans crews to the massive orbiting outpost.

    SpaceX signed a contract with NASA in 2006 to conduct twelve Falcon 9/Dragon resupply missions to carry about 44,000 pounds of cargo to the ISS at a cost of some $1.6 Billion over the next few years.

    This was the third test flight of the Falcon 9 rocket and the first test flight of the Dragon in this vastly upgraded configuration with solar panels. A future variant of Dragon will eventually blast US astronauts to space and restore US crew capability – perhaps by 2017 thanks to repeated cuts to NASA’s budget.

    Only four entities have ever sent a spacecraft to dock at the ISS – the United States, Russia, Japan and the European Union. SpaceX is the first commercial entity to accomplish the same feat.

    The precedent setting Dragon mission has opened a new era in spaceflight by giving birth to the first fully commercial mission to the orbiting space station complex and unlocking vast new possibilities for its utilization in science and exploration.

    On May 22, Dragon thundered to orbit atop a SpaceX built Falcon 9 rocket during a pre-dawn liftoff at 3:44 a.m. EDT from Space Launch Complex-40 on Cape Canaveral Air Force Station, Florida.

    After a three day chase, Dragon arrived at the ISS on May 25 and was deftly berthed at an open Earth-facing port on the Harmony Node 2 module after being dramatically captured by the astronaut crew using the station’s robotic arm in a landmark event in space history as the Dragon and the ISS were passing about 251 miles above Earth. Capture was confirmed at a mission elapsed time of 3 days, 6 hours and 11 minutes and 23 seconds.

    Working in tandem, NASA astronaut Don Pettit and ESA astronaut Andre Kuipers snared the Dragon craft as it was drifting in free space about 10 m (32 ft) away with the 18 m (58 ft) long Canadian robot arm at 9:56 a.m. EDT and parked the first privately built capsule to an open port at 12:02 p.m. EDT on May 25.

    The astronauts opened the hatch and ‘Entered the Dragon’ for the first time a day later on May 26 and then proceeded to unload the stowed cargo and refill it for the return trip to Earth.

    On this first NASA sponsored Dragon test flight to rendezvous and dock at the ISS, the cargo craft was packed with 460 kilograms (1014 lbs) of non-critical cargo including 306 kg (674 lbs) of food and crew provisions; 21 kg (46 lbs) of science experiment; 123 kg (271 lbs) prepositioned cargo bags to be used for future flights; and 10 kg (22 lbs) of assorted computer supplies and a laptop.

    Dragon splashed down successfully on May 31, 2012 at 11:42 a.m. EDT in the Pacific Ocean off the west coast of California. In a carefully timed sequence of events, dual drogue parachutes deployed at 45,000 feet to stabilize and slow the spacecraft. Full deployment of the drogues triggers the release of the main parachutes, each 116 feet in diameter, at about 10,000 feet, with the drogues detaching from the spacecraft. Main parachutes further slow the spacecraft's descent to approximately 16 to 18 feet per second.

    Unlike the other Russian, European and Japanese cargo freighters that service the ISS and then disintegrate on reentry, the SpaceX Dragon is uniquely equipped with a state of the art PICA-X heat shield that allows it to plunge safely through the Earth’s atmosphere and survive the fiery temperatures exceeding more than 3000 degrees F (1600 degrees C).

    SpaceX Falcon 9 rocket clears the tower after liftoff at 3:44 a.m. on May 22, 2012 from Space Launch Complex-40 at Cape Canaveral Air Force Station, Fla., on the first commercial mission to loft the Dragon cargo resupply vehicle to the International Space Station. The Dragon mission was a resounding success from launch to splashdown in the Pacific Ocean on May 31 at 11:42 a.m. EDT. Credit: Ken Kremer/www.kenkremer.com

    The down mass capability restores another critical capability lost with the forced retirement of NASA’s Space Shuttle orbiters in July 2011. The astronauts filled Dragon with about 620 kilograms (1367 pounds) of science experiments, trash and non-critical items on this historic test flight.

    The first operational Dragon resupply mission to the ISS could blast off as early as September, said Alan Lindenmoyer, manager of NASA’s Commercial Crew and Cargo Program.

    “We’ll await the final post flight report to make the determination that this was an extremely successful mission. But they should be well on their way to starting [delivery] services,” said Lindenmoyer at the briefing. “Of course, officially we will look at the post flight data and make an official determination. But I would say at this point it looks like 100 percent success.”

    Ken Kremer

    Video of California Daytime Fireball Surfaces

    Dr. Peter Jenniskens take a closer look at the image from the AVS Cineflex HiDEF camera mounted on the nose of the Eureka Airship. Mike Coop, can be seen in the background checking the map, further back other flight members continue to look for potential impact sites. Image credit: NASA / Eric James

    Video footage has finally surfaced of the daytime fireball that illuminated the sky over the Sierra Nevada Mountains in California back in April. NASA and the SETI Institute had asked the public to submit any amateur photos or video footage of the event, and previously a just few photos were taken of the event, even though it happened in broad daylight and created sonic booms that were heard over a wide area, back on Sunday, April 22, 2012 at 7:51 a.m. PDT. A few weeks later, Shon Bollock, who was making a time-lapse kayaking video just outside Kernville, California realized he had captured the bolide streaking through the air. This video shows the event several times, successively zooming in for a closer look. According to NASA it is the only footage of the meteor thus far.


    Meteorite hunters have been successful in locating fragments of the meteor, now called the Sutter’s Mill meteor since the event occurred near the area famous for where gold was discovered back in 1848, creating the California gold rush.

    NASA estimated fragments could be dispersed over a 16-km (10-mile) area.

    Phil Plait says the video is being studied by astronomers and meteoriticists to try to calculate the trajectory, speed, and possible orbit of the object, which is difficult with just one video, so if anyone finds they have ‘accidently’ taken footage of the event, contact the NASA Lunar Science Institute at the NASA Ames Research Center.

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    NASA used an airship to search for meteorites from this event. Noted meteorite expert Peter Jenniskens said the meteorites found so far from the fall are Carbonaceous Chondrites from the CM group of meteorites, “a rare type of primitive meteorite rich in organic compounds,”and scientists have precious few samples of this kind of material. The meteorites are very interesting to scientists from an astrobiology perspective, as they contain molecules related to how the building blocks for life on Earth may have been delivered from outer space. Scientist believe that this meteor could hold the answers to the origin of life on Earth and the universe. By studying the meteor, scientists also will learn more about the early solar system and the formation of our planets.

    “This is among the most chemically primitive meteorites,” said NLSI Deputy Director Greg Schmidt. “It’s like asking ‘how did life on Earth begin?’ and then having a fossil fall right in your back yard. This is exciting stuff — who knows what’s inside? The Sutter’s Mill Meteorite could be the most profound sample collected in over 40 years.”

    Via the Bad Astronomer

    Astrophoto: A Smokestack on the Sun by Monty Leventhal

    A Digital filtergram of a prominence on the Sun, May 29, 2012. Credit: Monty Leventhal, OAM.

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    This unusual prominence on the Sun looks like an exhaust-spewing smokestack. It was captured by noted Australian amateur astronomer Monty Leventhal on May 29, 2012. He used a Canon 600D camera with a Hydrogen-alpha filter and a Meade S.C. 10 inch telescope.

    Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

    Dragon Heading to Ocean Splashdown

    SpaceX Dragon has undocked from the International Space Station and is on course for May 31 splash down in the Pacific Ocean off the Baja California coast. Credit: NASA

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    History’s first commercial cargo ship ever to visit the International Space Station (ISS) has safely and successfully departed the orbiting lab complex after astronauts released the craft from the grip of the station’s robotic arm at 5:49 a.m. EST (949 GMT) this morning, May 31, 2012 for the return trip to Earth to conclude a precedent setting stay that fully accomplished all objectives.

    “Dragon is Free !” announced Josh Byerly, a NASA spokesman at Houston Mission control a short while ago as NASA astronauts Joe Acaba and Don Pettit released the first ever private spacecraft to attach to the ISS into a free drift mode for a fiery plunge through Earth’s atmosphere and splash down in the Pacific Ocean off the coast of Baja California less than 6 hours from now.

    “Everything looking safe and sound.”

    The two spacecraft were some 250 miles (400 km) high above the Indian Ocean east of Africa at the moment of release and departure. Altogether, Dragon spent 5 days, 16 hours and 5 minutes mated to the station.

    A minute later Dragon successfully conducted its first departure burn to back away from the massive orbiting complex followed shortly thereafter by two more short pulsed firings of the capsules thrusters. The last of the three short separation burns took place at 6:02 a.m. EDT.

    Dragon released from ISS robot arm on May 31. Credit: NASA

    The Dragon then passed outside the imaginary 200 meter (656 ft) circular zone known as the Keep-Out-Sphere (KOS) and was placed under the exclusive control of SpaceX mission controllers with NASA control duties completed

    The next major event is the de-orbit burn scheduled for 10:51 a.m. EDT which is a 100 m/sec burn lasting 9 minutes and 50 seconds. The thruster firing will send Dragon plummeting through the Earth’s atmosphere at 17000 MPH where it must survive temperatures exceeding 3000 degrees F before landing.

    Earlier this morning, Acaba and Pettit unhooked the final 16 motorized bolts and latches holding Dragon firmly to the station at the common berthing mechanism and detached Dragon from the station’s Earth facing Harmony node at 4:07 a.m. EDT using the 18 m (58 ft) Canadian robot arm. The astronauts worked at robotic work stations inside the multi-windowed Cupola observation dome.

    Dragon Splashdown Zone

    The SpaceX Dragon is now headed for a splashdown in the Pacific Ocean at 11:44 a.m. EST (1544 GMT) some 490 nautical miles southwest of Los Angeles off the West Coast of California.

    SpaceX has dispatched three recovery vessels to retrieve Dragon from the ocean.

    Following launch from Cape Canaveral, Florida on May 22, Dragon arrived at the ISS on May 25 and the astronauts opened the hatch on May 26 and then proceeded to unload the cargo and refill it for the return trip.

    Dragon is the world’s first commercial spacecraft and was built by Hawthorne, Calif., based SpaceX Corporation, founded in 2002 by CEO and Chief Designer Elon Musk.

    “This is SpaceX’s second demonstration flight under a 2006 Commercial Orbital Transportation Services (COTS) agreement with NASA to develop the capability to carry cargo to and from the International Space Station’” says SpaceX spokeswoman Kirstin Grantham.

    “With the first demonstration flight, in December of 2010, Dragon became the first commercial spacecraft to orbit the Earth and safely return. During that mission SpaceX conducted similar recovery operations to retrieve Dragon from a water landing in the Pacific. Demonstration missions are conducted to determine potential issues so that they might be addressed; by their very nature, they carry a significant risk. If any aspect of the mission is not successful, SpaceX will learn from the experience and try again.”

    Live NASA TV coverage of the Dragon splashdown resumes at 10:15 a.m. EDT

    Ken Kremer

    ……..

    Updated Dragon Return Timeline from SpaceX – (times are approximate and subject to change)
    Time (Pacific) Event
    02:49 Dragon released by the station’s robotic arm
    02:36 Dragon’s Draco thrusters fire first departure burn
    07:51 Draco thrusters fire deorbit burn
    08:09 Dragon’s trunk is jettisoned
    08:35 Drogue parachutes are deployed
    08:36 Main parachutes are deployed
    08:44 Dragon lands in the Pacific