Boulder CO (SPX) Jun 04, 2010 - Without warning, a mystery object struck Jupiter on July 19, 2009, leaving a dark bruise the size of the Pacific Ocean. The spot first caught the eye of an amateur astronomer in Australia, and soon, observatories around the world, including NASA's Hubble Space Telescope, were zeroing in on the unexpected blemish.

Astronomers had witnessed this kind of cosmic event before. Similar scars had been left behind during the course of a week in July 1994, when more than 20 pieces of Comet P/Shoemaker-Levy 9 (SL9) plunged into Jupiter's atmosphere. The 2009 impact occurred during the same week, 15 years later.

Astronomers who compared Hubble images of both collisions say the culprit may have been an asteroid about 1,600 feet (500 meters) wide. The images, therefore, may show for the first time the immediate aftermath of an asteroid, rather than a comet, striking another planet.

The Jupiter bombardments reveal that the solar system is a rambunctious place, where unpredictable events may occur more frequently than first thought. Jupiter impacts were expected to occur every few hundred to few thousand years. Although there are surveys to catalogue asteroids, many small bodies may still go unnoticed and show up anytime to wreak havoc.

"This solitary event caught us by surprise, and we can only see the aftermath of the impact, but fortunately we do have the 1994 Hubble observations that captured the full range of impact phenomena, including the nature of the objects from pre-impact observations" says astronomer Heidi Hammel of the Space Science Institute in Boulder, Colo., leader of the Jupiter impact study.

In 2009 Hammel's team snapped images of the debris field with Hubble's recently installed Wide Field Camera 3 and newly repaired Advanced Camera for Surveys.

The analysis revealed key differences between the two collisions (in 1994 and 2009), providing clues to the 2009 event. Astronomers saw a distinct halo around the 1994 impact sites in Hubble ultraviolet (UV) images, evidence of fine dust arising from a comet-fragment strike. The UV images also showed a strong contrast between impact-generated debris and Jupiter's clouds.

Hubble ultraviolet images of the 2009 impact showed no halo and also revealed that the site's contrast faded rapidly. Both clues suggest a lack of lightweight particles, providing circumstantial evidence for an impact by a solid asteroid rather than a dusty comet.

The elongated shape of the recent impact site also differs from the 1994 strike, indicating that the 2009 object descended from a shallower angle than the SL9 fragments. The 2009 body also came from a different direction than the SL9 pieces.

Team member Agustin Sanchez-Lavega of the University of the Basque Country in Bilbao, Spain, and colleagues performed an analysis of possible orbits that the 2009 impacting body could have taken to collide with Jupiter. Their work indicates the object probably came from the Hilda family of bodies, a secondary asteroid belt consisting of more than 1,100 asteroids orbiting near Jupiter.

The 2009 strike was equal to a few thousand standard nuclear bombs exploding, comparable to the blasts from the medium-sized fragments of SL9. The largest of those fragments created explosions that were many times more powerful than the world's entire nuclear arsenal blowing up at once.

The recent impact underscores the important work performed by amateur astronomers. "This event beautifully illustrates how amateur and professional astronomers can work together," notes Hammel.

Occasional dark spots have appeared on Jupiter throughout the history of sky watching. Observing records of the planet are filled with references to spots, including "white spots," "peculiar spots," and "well-defined spots." Only a handful may have described possible Jupiter strikes.

In 1686, the Italian astronomer Giovanni Cassini reported a dark spot on Jupiter that was roughly the size of the largest SL9 impact. Nearly 150 years later, in 1834, British astronomer George Airy independently reported a dark feature in Jupiter's southern belts that looked nearly four times as large as shadows cast on the planet by the Galilean moons. Crude telescopes prevented sky watchers from probing the nature of those spots.

The study by Hammel's team appeared in the June 1 issue of The Astrophysical Journal Letters.

Greenbelt MD (SPX) Jun 04, 2010 - NASA's Tropical Rainfall Measuring Mission and Aqua satellites are keeping a close eye on Cyclone Phet, a monster cyclone in the Arabian Sea, now affecting coastal Oman. Cyclone Phet's winds and heavy rains reached Oman's east coast earlier, June 3.

Authorities in Oman have raised the threat level to orange, and evacuations have already taken place.

Yesterday, when Phet was powering up from a Category three to a Category four cyclone on the Saffir-Simpson scale, the Tropical Rainfall Measuring Mission or TRMM satellite traveled almost directly above Phet in the Arabian Sea.

On June 2 at 0140 UTC (June 1 at 9:40 p.m. EDT) TRMM data showed that numerous powerful thunderstorms were imbedded in Phet's well defined eye wall. They were producing very heavy rainfall of over 50 mm/hr (~2 inches). That rainfall is affecting the coast of Oman.

At 0900 UTC (5 a.m. EDT), June 3, Cyclone Phet (a Category 4 storm on the Saffir-Simpson scale) was located about 275 nautical miles south of Muscat, Oman, near 19.2 North and 59.3 East. Phet's maximum sustained winds were near 115 knots (132 mph) with gusts to 140 knots (161 mph). Phet has moved on a north-northwestward track at 4 knots (5 mph).

Phet is creating extremely dangerous seas along the coast of Oman, with waves as high as 30 feet, so all fishing and other boats have been warned not to venture to sea.

Forecasters at the Joint Typhoon Warning Center using animated multispectral imagery noted this morning that the imagery indicates the system has regained a 20-nautical mile wide ragged eye that appeared to wobble as the cyclone underwent a possible eye-wall replacement.

The Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite captured an infrared image of Cyclone Phet on June 3 at 08:59 UTC (4:59 a.m. EDT) in which the western half of the storm was already on top of coastal Oman. It showed a large area of strong thunderstorms with high, cold cloud tops as cold as -63 Fahrenheit.

Phet is in an area of low vertical wind shear. Vertical wind shear means winds blowing at different directions at different levels in the atmosphere that can tear a storm apart. When vertical wind shear is strong, it weakens tropical cyclones. When wind shear is weak, it allows tropical cyclones to maintain or increase intensity.

Water vapor imagery from satellites do indicate that as Phet continues moving through the Arabian Sea, it will encounter dry air, which will help weaken the cyclone. The friction of the storm raking over the Oman coast will also contribute to weakening the cyclone.

After skirting the Oman coast, Phet is expected to swing eastward and make landfall just north of Karachi, Pakistan.

Tempe AZ (SPX) Jun 04, 2010 - It's amazing what cleaning your glasses can reveal. A mineral-scouting instrument developed at ASU's Mars Space Flight Facility has found an outcrop of rock rich in carbonate minerals in the Columbia Hills of Gusev Crater on Mars, according to a report published online June 3 in the journal Science. The instrument is onboard NASA's Mars Exploration Rover Spirit.

What makes the discovery unusual is that Spirit visited the outcrop, dubbed Comanche, back in December 2005. Yet the data pointing to the discovery languished since then because one of the instruments that detected the carbonate minerals was partly blinded by dust.

Dust in your eye
The instrument is the Miniature Thermal Emission Spectrometer, or Mini-TES, developed at Arizona State University. Each of the two Mars rovers carries a Mini-TES to identify minerals in rocks nearby. The instrument was designed by its principal investigator, Philip Christensen, an ASU Regents' Professor in the School of Earth and Space Exploration, part of the College of Liberal Arts and Sciences.

"Mini-TES got dusted months before Spirit reached Comanche, and we didn't have a good way to correct for the dust effects at the time," said Steve Ruff, research scientist at ASU's Mars Space Flight Facility. Ruff is one of a team of scientists on the paper, whose lead author is Richard V. Morris of NASA's Johnson Space Center in Houston. "We knew there was something weird about the outcrop's spectrum as seen by Mini-TES, but couldn't say what caused it."

Ruff added, "Spirit's Mossbauer spectrometer indicated that carbonate was possible, but I didn't believe it."

What finally did the trick was developing a calibration to remove the spectral effects of the dust on the instrument. Combined with the Mossbauer data and chemical data from a third spectrometer, "the Mini-TES spectra put the discovery over the edge," Ruff said.

Warmer, wetter Mars?
Scientists have been searching for Martian carbonate rocks for decades because such minerals are crucial to understanding the early climate history of Mars and the related question of whether the planet might once have held life.

"Small amounts of carbonate minerals have been detected on Mars before," Ruff said.

The difference this time, he said, "is that we're seeing a couple of large outcrops of rock poking through the soil of the Columbia Hills. The rocks are about 25 percent carbonate by weight, by far the highest abundance we've seen on Mars."

Born of water
Comanche and a neighboring small outcrop dubbed Comanche Spur have the same granular texture and Mini-TES spectral nature. Ruff says they are part of a stack of volcanic sedimentary rocks, draped over the underlying terrain.

"They're definitely a puzzle to understand," Ruff said. "The outcrops are very rich in olivine, a volcanic mineral, but they appear to have been soaked in water." He explains that it's as if the granular material settled over a preexisting landscape, then the entire stack was flooded with carbonate-rich water, probably from a hydrothermal source.

NASA's other Mars rover, Opportunity, has discovered ample evidence for alteration of rocks by water in Meridiani Planum, on the other side of Mars from Spirit's Gusev Crater. But the water at Meridiani was strongly acidic. While life can evolve to survive in acidic conditions - such as in some of Yellowstone National Park's geysers and hot springs - few scientists think it can start under those conditions.

Moreover, acidic water quickly destroys carbonate minerals, as for example vinegar dissolves hard water deposits. Thus finding outcrops of carbonate rock shows that the hydrothermal water at Comanche was liquid, chemically neutral, and abundant.

While there's no evidence for life, Ruff said, the conditions would have been more favorable for it.

In plain view
Ironically, Ruff noted that the new finding complicates the story of the Columbia Hills.

"This makes the geology harder to understand," he said. "It adds another environment to incorporate into the picture of how the Hills formed.

"The Comanche data have been available to scientists and the public for about four years now," Ruff said. "The new finding shows that this data set still harbors potentially major discoveries."

"Do other surprises await us? Who knows? But I'll make a strong prediction: More discoveries will be made with old data."

Heidelberg, Germany (SPX) Jun 03, 2010 - By exploiting the exquisite image quality of the NASA/ESA Hubble Space Telescope and comparing two observations made ten years apart astronomers have, for the first time, managed to measure the tiny motions of several hundred young stars within the central cluster of the star-forming region NGC 3603.

The team was surprised to find that the stars are moving in ways that are at odds with the current understanding of how such clusters evolve. The stars in the cluster have not "settled down" as expected.

With a mass of more than 10 000 suns packed into a volume with a diameter of a mere three light-years, the massive young star cluster in the nebula NGC 3603 is one of the most compact stellar clusters in the Milky Way [1] and an ideal place to test theories for their formation.

A team of astronomers from the Max-Planck Institute for Astronomy in Heidelberg and the University of Cologne led by Wolfgang Brandner (MPIA) wanted to track the movement of the cluster's many stars. Such a study could reveal whether the stars were in the process of drifting apart, or about to settle down.

The cluster, formally known as the NGC 3603 Young Cluster, is about 20 000 light-years from the Sun which makes these measurements extraordinarily difficult. It is necessary to compare images that were made years or even decades apart. The telescope and camera used must give very sharp images and be extremely stable over long periods.

Brandner and his colleagues realised that the Hubble Space Telescope was the best for the job. They found good data in the archives for the NGC 3603 cluster from a July 1997 observing run with the Wide Field Planetary Camera 2 (WFPC2), and then made their own follow-up observations in September 2007, using the same camera and the same set of filters as in the original observations. It then took the team two years of very careful analysis to extract reliable estimates for the motions of stars in the images.

Boyke Rochau (MPIA), the paper's lead author, who performed this analysis as part of his PhD work, explains: "Our measurements have a precision of 27 millionths of an arcsecond per year. This tiny angle corresponds to the apparent thickness of a human hair seen from a distance of 800 km."

In this laborious way, they were able to measure the precise speeds of more than 800 stars. About 50 were identified as foreground stars that are unrelated to the cluster, but more than 700 cluster stars of different masses and surface temperatures remained. The results for the motion of these cluster stars were surprising: this very massive star cluster has not yet settled down. Instead, the stars' velocities were independent of their mass and thus still reflect conditions from the time the cluster was formed, approximately one million years ago.

Stars are born when a gigantic cloud of gas and dust collapses. In cases such as the star forming region NGC 3603, where the cloud is unusually massive and compact, the process is particularly quick and intense. Most of the cloud's matter ends up concentrated inside hot young stars and the cluster keeps much of its initial gravitational attraction [2].

In the long term such massive compact star clusters may lead to the development of the huge balls of stars known as globular clusters, whose tightly packed stars remain held together by gravity for billions of years.

Wolfgang Brandner adds: "This is the first time we have been able to measure precise stellar motions in such a compact young star cluster." Team member Andrea Stolte from the University of Cologne adds: "This is key information for astronomers trying to understand how such clusters are formed, and how they evolve."

Moscow, Russia (ESA) Jun 04, 2010 - Hatch closed: 18-month Mars500 mission has begun. Mars500, the first full-length simulated mission to Mars, started today in Moscow at 13:49 local time (11:49 CET), when the six-man crew entered their 'spacecraft' and the hatch was closed. The experiment will run until November next year.

The mood was serious and very determined in the Mars500 facility at the Institute of Biomedical Problems in Moscow this afternoon, as the crew talked to the press and then walked into the modules that will be their home for the next 520 days.

Diego Urbina and Romain Charles from Europe, Sukhrob Kamolov, Alexey Sitev, Alexandr Smoleevskiy and Mikhail Sinelnikov from Russia and Wang Yue from China face a mission that is as close as possible to a real space voyage without leaving the ground. They will live and work like astronauts, eat special food and exercise in the same way as crews aboard the International Space Station.

Their mission is to 'fly to Mars' in 250 days, 'land on and explore Mars' for a month and 'return to Earth' in 230 days, using their imitation interplanetary spacecraft, lander and martian surface.

The hatch will remain closed until November 2011 and the crew must manage using the food and equipment stored in the facility. Only electricity, water and some air will be fed into the compartments from outside.

Problems ahead
In addition to testing many novel technologies, Mars500 is an extreme test of human endurance. Staying almost 18 months inside the metallic containers will be hard, even after being trained and briefed by astronauts and submariners.

The crew will no doubt have their ups and downs during the long mission, and these psychological changes are a key part of the experiment.

The 'astronauts' will normally divide their weekdays equally between work, free time and rest, with the weekends usually free. They have taken plenty of films, books, games, musical instruments and entertainment with them.

Their bodies will start to adapt to the new conditions - a closed environment with restricted space can quickly lead to poor physical condition. The crew need to exercise up to two hours a day, but they can shower only once a week.

What have I forgotten? Preparing everything from soap and clothing to food and spare camera batteries for a self-contained 18-month mission is a critical and complex task.

And finally the technology: the facility is not a spacecraft, but it uses many systems that will be found on a real Mars craft. Testing these in realistic conditions is important. The crew have been trained to repair every single bolt of their 'craft' and outside help will be given only in extreme situations.

related report
Mars 'expedition' starts in Moscow
The participants in a simulated Mars expedition waved good-bye to journalists, sealed the hatches and "took off" for a 520-day "space trip" on Thursday, a spokesman for the Moscow Institute of Medical and Biological Problems said.

Six people will take part in the experiment in the Mars-500 module, which will simulate all aspects of a journey to the Red Planet, with a 250-day trip there, a 30-day stay on its surface, and a 240-day return flight, Pavel Morgunov said.

The exploration of Mars has been an important part of the space exploration programs of the Soviet Union, the United States, Europe, and Japan. It has become a focus of the U.S. space program as President Barack Obama scrapped the lunar program earlier this year.

During nearly two years of isolation, the crew members will experience many of the conditions likely to be encountered by astronauts on a real space flight, except for radiation and weightlessness.

Three of the six crew members will leave the "spacecraft" and "walk" on Mars, becoming the first people to "set foot" on the Red Planet.

Each of the crew members will receive about 3 million rubles ($100,000) for participating in the mission, which is headed by Russia's Alexei Sityev.

The crew will communicate with Earth via e-mails with a 40-minute delay, Morgunov said. The crew's "spacecraft" is equipped with a laboratory, living area, warehouse and mini-garden.

The project initially involved 11 candidates: seven candidates from Russia and one each from China, France, Italy and Belgium. Three Russians, a Frenchman, a Chinese, and an Italian have been selected to take part in the mission.

The French astronaut packed a guitar for the mission, while his Italian space buddy took an electronic percussion instrument "to accompany his friend."

Morgunov said that after this mission is completed, the next one was proposed to be comprised of women.

related report
Google launches Mars flight simulation mission's online flight logbook
The Russian scientific institute that started on Thursday the Mars-500 simulation of a manned mission to the Red Planet has launched an interactive website on the experiment in cooperation with Google.

The new website, created by Google and the Moscow Institute of Medical and Biological Problems, carries a wealth of information about the 520-day experiment and about the planet itself.

The logbook is based on Google Blogger platform and is fully devoted to the Mars-500 project.

Google said in a statement that the site (http://mars500main.appspot.com/#en) would allow visitors to "experience what the flight to Mars is like" and let them explore the Red Planet.

"You'll be able to watch detailed video reports about Mars-500 and take a virtual tour of Mars. Walk along the Valles Marineris canyons, climb the Olympus Mons, (or even) take a peek into the Gusev crater or climb down into one of Mars' lakes," the statement said.

Visitors will also be able to monitor the progress of the flight with an interactive map showing the location of the 'spaceship,' its speed and distance covered.

Six people are taking part in the experiment in the Mars-500 module, which will simulate all aspects of a journey to the Red Planet, with a 250-day trip there, a 30-day stay on the surface, and a 240-day return flight.

During nearly a year and a half of isolation, the crew members will experience many of the conditions likely to be encountered by astronauts on a real space flight, except for radiation and weightlessness.

Meanwhile, a real mission to the Red Planet will not become possible until at least 2030 or 2035, the head of Roscosmos manned spaceflight programs, Alexei Krasnov said on Thursday.

"A real mission to Mars before 2035 is hardly possible. Present technology does not allow us to build a Martian spacecraft small enough: if you built it now, it would be the size of the International Space Station," Krasnov said.

Pasadena CA (JPL) Jun 04, 2010 - These images, acquired on May 24, 2010 by the Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard NASA's Terra spacecraft, show the encroachment of oil from the former Deepwater Horizon rig into Louisiana's wildlife habitats. The source of the spill is located off the southeastern (bottom right) edge of the images.

Dark filaments of oil are seen approaching the shores of Blind Bay and Redfish Bay at the eastern edge of the Mississippi River delta, and also nearing Garden Island Bay and East Bay farther to the south. These areas are home to many varieties of fish. To the north, the arc-shaped pattern of land and runoff is associated with the Chandeleur Islands, which are part of the Breton National Wildlife Refuge.

This refuge is the second oldest in the United States and is a habitat for dozens of seabird, shorebird and waterfowl species. Oil is reported to have reached the islands on May 6. Eighteen days later, this image shows filaments of oil crossing the island barrier - which had been heavily eroded by Hurricane Katrina in 2005 - and entering the Breton and Chandeleur Sounds.

The left-hand image contains data from MISR's vertical-viewing camera. It is shown in near-true color, except that data from the instrument's near-infrared band, where vegetation appears bright, have been blended with the instrument's green band to enhance the appearance of vegetation.

The Mississippi River delta is located below the image center. The slick is seen approaching the delta from the lower right, and filaments of oil are also apparent farther to the north (towards the top). The oil is made visible by sun reflecting off the sea surface at the same angle from which the instrument is viewing it, a phenomenon known as sunglint.

Oil makes the surface look brighter under these viewing conditions than it would if no oil were present. However, other factors can also cause enhanced glint, such as reduced surface wind speed. To separate glint patterns due to oil from these other factors, additional information from MISR's cameras is used in the right-hand image.

Previous MISR imagery of the spill shows that the contrast of the oil against the surroundings is enhanced by using a combination of vertical views and oblique-angle views.

The right-hand panel was constructed by combining data from several MISR channels. In this false-color view, oil appears in shades of inky blue to black; silt-laden water due to runoff from the Mississippi River shows up as orange, red and violet; and land and clouds appear in shades of cyan.

The images cover an area measuring 110 by 119 kilometers (68 by 74 miles).

A detailed literature review by Showman et al available on arXiv, outlines the scant observational data available on exoplanet atmospheres and then explores in detail what exoplanet atmospheres might be like, based on solar system examples and associated theory.(...)
Read the rest of Astronomy Without A Telescope – Exoplanet Weather Report (613 words)

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Logical explanations take all the fun out of UFO's. After the Falcon 9 rocket launched successfully, later, over on the other side of the world, people in Australia saw a spiraling object in their early morning skies, about 6 am local time. Geoffrey Wyatt, from the Sydney Observatory, said it appeared to have been the Falcon 9 rocket, which launched about an hour earlier.

Another image below.
(...)
Read the rest of Spirialing 'UFO' Over Australia Was Likely Falcon 9 Rocket (76 words)

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SPACE.com - The long-standing mystery over exactly what famed poet Walt Whitman saw streaking though the sky 150 years ago has apparently been solved by a team of bookworm astronomers.

A Prandtl–Glauert singularity, or shock cone forms around the Falcon 9 rocket during launch. Credit: Alan Walters (awaltersphoto.com) for Universe Today.

Universe Today photographer Alan Walters was on hand for Friday's spectacular and picture-perfect launch of SpaceX's Falcon 9 rocket. Enjoy a gallery of images, including this great shot of a Prandtl–Glauert singularity, or shock cone that formed around the rocket, which sometimes occurs when a sudden drop in air pressure occurs when rockets or aircraft are traveling at transonic speeds.

"This has really been a fantastic day," said an exuberant Elon Musk, CEO of SpaceX, speaking with reporters after the flight. “It’s been one of the best days of my life. It’s certainly been one of the greatest days for the people of SpaceX.”
(...)
Read the rest of Falcon 9 Launch Gallery; 'Fantastic Day,' P–G Singularity and More (113 words)

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The brand new commercial Falcon 9 rocket soared into orbit from Florida on its maiden flight Friday, the first test for a new era of private vehicles that could one day send cargo - and possibly astronauts - into space.

NASA's space shuttle fleet may be retiring but here are 10 new spaceships ready to fill the void.

Is national hero Neil Armstrong being manipulated? SPACEX founder Elon Musk thinks it's a possibility.

The successful liftoff of a new private rocket helps vindicate President Barack Obama's plan to rely on commercial spaceships to carry cargo and possibly astronauts to orbit, the rocket's millionaire owner said.

The Rockot launcher, a modified Russian ballistic missile, lifted off Wednesday. June 2, 2010, with a Japanese satellite.

SPACE.com's launch updates for the first SpaceX Falcon 9 rocket launch on June 4, 2010.

As the era of private spaceflight takes a step forward with SpaceX's Falcon 9 rocket test, here's a look at 6 companies that could launch humans into space soon.

The planet Uranus can be spotted in the night sky using Jupiter as guide this week, a challenging — but rewarding — target for skywatchers.

A huge fireball has been spotted on Jupiter in yet another collision from space caught on camera and video by amateur astronomers.

The stakes are high for SpaceX's new private Falcon 9 rocket for its first test launch today.