Space and astronomy news
If you’re going to be anywhere near a computer connected to the Internet on Tuesday, why not tune into NASA television and watch the launch of the first Mars Explorer rover. NASA’s set up a fast-loading page that will have operational links when their coverage gets started, so you can tune in.
Coverage begins 1600 GMT (12:00pm EDT). Click here to see the page, and then bookmark it so you can check back tomorrow.
I’ll be watching.
Fraser Cain
Publisher
Universe Today
Image credit: ILS
A Russian-built Proton K rocket successfully launched the AMC-9 satellite on Saturday, completing the 300th launch of this rocket design over the course of 38 years. The Proton lifted off from the Baikonur Cosmodrome at 2215 GMT (6:15pm EDT), and the satellite separated from the Breeze M upper stage nearly nine hours later. The AMC-9 will provide digital television, data, and telecommunications services.
A Proton rocket successfully placed the AMC-9 satellite into orbit this morning for Alcatel Space and SES AMERICOM. The launch was conducted by the U.S.-Russian joint venture International Launch Services (ILS).
This marks the 300th flight of a Proton vehicle, including 38 years of Russian federal missions and seven years with commercial flights under the auspices of ILS. Today?s mission was the first Proton rocket launch of the year for ILS.
The vehicle used today was Proton vehicle with a Breeze M upper stage, which lifted off from the Baikonur Cosmodrome at 4:15 a.m. local time (22:15 June 6 GMT, 6:15 p.m. June 6 EDT). After 8 hours and 55 minutes, the AMC-9 satellite was separated from the Breeze M and placed into geostationary transfer orbit. Satellite builder Alcatel Space of Cannes, France, contracted for the launch as a delivery-in-orbit mission.
?Once again, Proton demonstrated that it is one of the most reliable vehicles in the world,? ILS President Mark Albrecht said. ?It?s a pleasure to provide both Alcatel Space and SES AMERICOM with another excellent launch.?
?I am delighted about the launch of AMC-9, a satellite that is important to our plans for growth of the AMC fleet,? said Dean Olmstead, president and CEO of SES AMERICOM. ?I extend warm congratulations to the entire team on the occasion of this picture-perfect launch and achieving the great 300th Proton mission milestone.?
This also was ILS? 14th launch of a satellite for a member of the SES GLOBAL family of companies ? SES AMERICOM and its predecessor GE AMERICOM, SES ASTRA and AsiaSat. In addition, ILS is scheduled to launch three more AMC satellites on either Proton or Atlas rockets in the 2003-04 time frame, and has recently acquired a fourth, not yet identified AMC mission.
This also is the eighth Alcatel Space-built satellite launched by ILS. AMC-9 is a Spacebus 3000B3 model with 48 transponders. It will enable SES AMERICOM, an SES GLOBAL company, to expand its digital television broadcasting, data transmission and telecommunication service offerings to North America.
ILS is a joint venture of Lockheed Martin Corp. (NYSE:LMT) in the United States, which builds the Atlas rocket; and Russian companies Khrunichev State Research and Production Space Center and RSC Energia. Khrunichev produces the Proton vehicles and the Breeze M upper stage.
ILS was formed in 1995 to provide launch services to customers worldwide, including technical, management and marketing expertise. It offers the broadest range of launch services in the world along with the highest reliability in the industry.
Original Source: ILS News Release
The launch of NASA’s Mars Explorer spacecraft was pushed back to Tuesday because of bad weather at the Cape Canaveral, Florida launch pad. The spacecraft was originally supposed to lift off on Sunday, but storms forced the controllers to delay the launch, and then again on Monday. If the weather behaves, Explorer will lift off at 1758 GMT (1:58 pm EDT) and carry the newly named rover “Spirit” towards Mars. The second rover, “Opportunity” will follow on June 25.
Image credit: NASA
A year’s worth of observations from the Mars Odyssey spacecraft is starting to overturn some older theories about how environmentally active the Red Planet is. Using Odyssey’s Thermal Emission Imaging System (THEMIS), scientists were able to detect geological formations of lava and rock which were deposited under varying environmental condition. One example is kilometre wide sheets of bedrock which are being scoured bare by wind. If Mars were less active, they should be covered in sand and dust.
The first overview analysis of a year’s worth of high-resolution infrared data gathered by the Thermal Emission Imaging System (THEMIS) on NASA’s Mars Odyssey spacecraft is opening Mars to a new kind of detailed geological analysis and revealing a dynamic planet that has experienced dramatic environmental change.
The report by THEMIS’s science team will appear in an upcoming issue of Science and will be released on June 5 in the magazine’s online preview, Science Express.
“THEMIS is creating a set of data that is going to revolutionize our mapping of the planet and our idea of the planet’s geology,” said lead author and THEMIS Principal Investigator Philip Christensen, Korrick Professor of Geological Sciences at Arizona State University. “It will keep Mars scientists busy for the next 20 years trying to understand the processes that have produced this landscape.”
THEMIS is providing planetary geologists with detailed temperature and infrared radiation images of the martian surface. The images reveal geological details that were impossible to detect even with the high-resolution Mars Orbital Camera on NASA’s Mars Global Surveyor and that have 300 times higher resolution than MGS’s Thermal Emission Spectrometer. Among the significant findings noted in the report is the detection of layers in the martian surface that indicate major changes in past environmental conditions.
“With a visible light camera, I can take a picture of a lava flow, but even with the highest resolution cameras that we have today the smallest thing we can see is the size of a bus and in order to do geology I need to have more detail,” said Christensen.
“The camera on Mars Global Surveyor takes exquisite images that show layers, but it doesn’t tell me anything about composition – is it a layer of boulders with a layer of sand on top? I have no way of knowing. With the THEMIS temperature data, I can actually get an idea because the layers vary – and each layer has remarkably different physical properties.”
Daytime and nighttime temperature data can allow scientists to distinguish between solid rock and a variety of loose materials, from boulders to sand and dust. As any beach-goer knows, fine-grained sand heats up more rapidly at the surface than solid stone (which transmits more heat inward) but it also cools off more rapidly at night, when solid materials retain heat.
“We have seen layers, each with dramatically different physical properties, in places like Terra Meridiani,” Christensen said. “Why do the physical properties in the different layers change? They change because the environment in which those rocks were deposited changed.
“It’s very difficult to say exactly what happened in any particular place, but what we’ve found is that in many places on Mars it hasn’t just been the same old thing happening for year after year for billions of years. These data have been so remarkable and so different from all of our previous experience that it has taken time to sift through the images and figure out what we’re seeing.”
Among the details that have stood out so far are kilometer-wide stretches of bare bedrock that Christensen notes were unexpected, given the Mars’ known dustiness. Large areas of exposed rock indicate that strong environmental forces are currently at work, “scouring” from the surface any past sediment as well as any new material that might be falling from the atmosphere.
Also unexpected is the finding that accumulations of loose rock are common on martian hillsides, indicating recent processes of weathering continuing to affect the planet. ” If those rocks had been made a billion years ago, they’d be covered with dust,” Christensen pointed out. “This shows a dynamic Mars – it’s an active place.”
However, despite Odyssey’s past findings of significant martian ice deposits, there are also indications that, in many places on the planet, water may not be one of the active causes behind the observed geological features.
Analyzing the spectra from the ten different bands of infrared light the instrument can detect, the THEMIS team has begun to identify specific mineral deposits, including a significant layer of the mineral olivine near the bottom of a four-and-a-half kilometer deep canyon known as Ganges Chasma. Olivine, Christensen notes, is significant because it decomposes rapidly in the presence of water.
“This gives us an interesting perspective of water on Mars,” he said. “There can’t have been much water – ever — in this place. If there was groundwater present when it was deep within the surface, the olivine would have disappeared. And since the canyon has opened up, if there had ever been water at the surface it would be gone too. This is a very dry place, because it’s been exposed for hundreds of millions of years. We know that some places on Mars have water, but here we see that some really don’t.”
Overall, Christensen notes that the emerging diversity and complexity of the planet point to the likelihood of future surprises and keep enlarging the possibilities for discovery on Mars.
“With Odyssey, we are looking at Mars in its entirety, in context. It’s remarkable how much this has already changed our view of the complexity and richness of the planet. We discovered that it has a really dynamic geologic history. It has far more ice and water than we thought — we’re seeing snow and gullies, layers – and there are also processes involving volcanoes, impact craters and wind. It’s a fascinating place.”
Original Source: NASA News Release
Our Earth might have formed a lot earlier that astronomers previously believed, maybe as quickly as 10 million years after the birth of the Sun. In fact, all of the inner planets might have started forming as soon as 10,000 years after the Sun ignited 4.5 billion years ago. Within 10 million years, the Earth had reached 64 percent of its mass, and later collided with a Mars-sized object to provide additional mass and create the Moon. Scientists originally believed that the Earth took 50 million years to form.
If you’ve spent some time on the Internet, you’ve come across the Astronomy Picture of the Day (APoD) website, run by astrophysicists Robert Nemiroff and Jerry Bonnell. Once a day they post up a space-related picture, provide a handy description. I’ve said to myself on several occasions, that these guys should write a book. Well, now they have.
The Universe: 365 Days ($20.97 from Amazon.com) is a print version of APoD, and it’s one of the most gorgeous astronomy books I’ve ever seen. Open it up to any page: on your right is a full-page photograph, and on your left is a paragraph description about the picture. That’s it, 365 pages of description/picture, rinse, repeat. Not much else to say. If you like pictures of space and astronomy, then you’re going love it, page after page.
Because there are so many photographs, the authors were able to draw from a large pool of images. So, it isn’t just the same old NASA/Hubble pictures that everyone uses, there are some from more obscure observatories and even amateur astronomers. There’s a handy index at the back so you seek out images by topic.
I understand why they decided to go with the whole 365 days concept; it’s a connection to their website. But then, it’s not like you’re going to read the book one day at a time, like some kind of yearlong astronomical advent calendar.
Let me just stick my drooling tongue back in my mouth for a second and let you know my complaints with the book. First, the text is really small. Unreasonably small considering that it’s swimming in white space. The layout person should have been thinking about all the people who might be reading this book, and steered well away from 9 point font. My other complaint is that it feels fragile. Imagine you’re holding a stack of nearly 400 photographs bound together on the left-hand side. I’m worried that it might come apart with all the use it’ll get sitting on a coffee table. I’m afraid to let Chloe look through it, as she’ll render it into pulp in minutes.
Still, complaints aside The Universe: 365 Days is a fantastic book. Gorgeous photographs put into context by scientists who’ve had years of experience boiling complex concepts into handy, bite-sized write-ups. Hey, that’s what I do?
Image credit: ESA
Europe’s mission to Mars continues with the next crucial step of Mars Express’ journey out of the way. The clamps holding Beagle 2 tightly during launch were released over the course of 30 minutes on Thursday morning. If this phase had malfunctioned, Mars Express wouldn’t have been able to release Beagle 2 when they reached Mars, ending the mission before it had begun. The spacecraft is expected to arrive at Mars in late December.
Europe’s first mission to the Red Planet, continues its successful mission with another successful ‘high-risk’ post-launch milestone. Mars Express engineers breathed a sigh of relief this morning at the European Space Operations Centre (ESOC), in Germany.
If a particularly delicate operation had not proceeded as planned, it would have been impossible to deploy the Mars Express lander, Beagle 2, on arrival at Mars.
This crucial operation consisted of releasing Beagle-2’s launch clamps. These clamps are extra attachments that ensure the lander stays perfectly fixed to the spacecraft during the launch and is not affected by launch vibrations. After the launch, these clamps are no longer needed, since another mechanism keeps Beagle 2 in place during the six-month trip to the Red Planet.
This second mechanism allows Mars Express to deploy Beagle 2 on arrival at Mars. However, if the launch clamps had not released today, the second mechanism would have failed. “The Beagle-2 mission would have been over before it had even started!” commented ESA Lander Manager, Con McCarthy.
The release of the launch clamps started at 10.10 CEST and lasted about 30 minutes. The release mechanism itself is unusual. Usually, launch clamps contain a firework-like mechanism, but Mars Express had a much gentler release mechanism for Beagle. It consisted of a sleeve over a clamp bolt; an electric current heats the sleeve to about 100?C. At that temperature, the sleeve expands and the bolt snaps. There were three bolts and they all broke in sequence.
“We had to wait two minutes for the expansion of the sleeve which snapped the bolt. The atmosphere in the room was tense and those two minutes seemed to last an eternity! When the first bolt went, a lot of tension was released,” says McCarthy.
There are more hurdles ahead but Mars Express is demonstrating that it can deal with the many challenges on the way to the Red Planet.
Original Source: ESA News Release
Thunderstorms in Texas have forced investigators to push back a crucial test to determine if foam could actually cause the damage that destroyed the space shuttle Columbia in February. On this next test, they will fire a chunk of foam at a real shuttle wing, donated by the space shuttle Discovery. Investigators didn’t want to risk getting their camera equipment wet from the driving rain, so they decided it was best to push the test back.
Image credit: NASA
When the Voyager spacecraft zipped past Saturn in 1980/81, they clocked the ringed planets equatorial winds at 1700 km/h. But a team of Spanish and American astronomers recently measured the motions of clouds and storms on Saturn using the Hubble Space Telescope and found they were only going 990 km/h. Although the equatorial winds have slowed down, other jets further away from the equator are still moving the same speed. This has led the astronomers to believe that the slow-down has something to do with the change of seasons on Saturn.
Saturn, one of the windiest planets, has recently had an unexpected and dramatic change in weather: its equatorial winds have subsided from a rapid 1700 km/hr during the Voyager spacecraft flybys in 1980-81 to a modest 990 km/hr from 1996 to 2002. This slow-down in the winds has been detected by a Spanish-American team of scientists, including Richard French of Wellesley College in Massachusetts, who report their findings in the June 5 issue of the journal, Nature. (5 June 2003, Vol. 423, pp. 623-625)
Using Hubble Space Telescope (HST) images of the ringed giant planet, the scientists (A. Sanchez-Lavega, S. Perez-Hoyos, J. F. Rojas, and R. Hueso from Universidad Pais Vasco in Bilbao, Spain, and French from Wellesley College), measured the motions of cloud features and storm systems on the ringed giant planet.
“One of the major mysteries in atmospheric sciences is why the giant planets Jupiter and Saturn — huge spheres composed mainly of hydrogen and helium — have an alternating pattern of east-west winds, which vary in direction with latitude,” explains French. “Unlike winds on terrestrial planets like Earth, which are powered primarily by sunlight, winds on the giant planets have an additional energy source in the heat that escapes from their deep interiors. Even though the strength of this interior heat is a mere fraction of the sunlight on Earth, the giant planets’ winds are ten times more intense than terrestrial winds.”
The role of these interior energy sources in sustaining these strong winds in giant planets and understanding why the maximum speed is reached at the equator constitute major challenges to theories of atmospheric motion in planets and stars.
There currently are two quite different explanations for the system of jets on giant planets. At one extreme, the winds are thought to extend very deep into the interior of the planet, tapping the heat released from the planet to drive their motions. At the other extreme, the atmospheric circulation is modelled as on the terrestrial planets, driven by the solar heat deposited in a shallow upper atmospheric layer. Both explanations have important drawbacks, and neither can account for the strong equatorial winds.
One way to test these models is to analyse the long-term behaviour of the winds by measuring their sensitivity to changes in the amount of sunlight due to seasonal effects or to other influences. Previous studies showed that Jupiter?s winds are quite stable, and not sensitive to seasonal changes, but little was known about Saturn, whose muted cloud features are much harder to measure.
Using the high-resolution capability of the Wide Field Planetary Camera onboard the HST, the Spanish-American team has been able to track enough cloud elements in Saturn to measure the wind velocity over a broad range of latitudes. The equatorial winds measured in 1996-2001 are only half as strong as was found in 1980-81, when the Voyager spacecraft visited the planet. In contrast, the windy jets far from the equator have remained stable and show a strong hemispheric symmetry not found in Jupiter.
The different behaviour of Saturn?s winds could have a simple explanation, note the scientists. The long seasonal cycle in Saturn?s atmosphere (one Saturn year is about thirty terrestrial years) and the equatorial shadowing by the planet?s giant rings could account for the sudden slowdown in the equatorial winds. Rather than being tied to the deep interior of Saturn, driven primarily by internal heat, the equatorial winds could be in part a shallow surface phenomenon, affected as well by seasonal variations in sunlight. In fact, Saturn?s equatorial region has been the location of giant storm systems, such as those seen in 1990 and 1994. These storms may have induced strong dynamical changes, perhaps resulting in the observed weakening of the equatorial winds.
Another possibility is that the winds measured by the team are at higher altitudes where the winds are likely to decrease in speed. In the Nature article, the team notes that Saturn?s non-equatorial winds have remained unchanged during this period, resembling Jupiter in this respect, which hints that these winds could be more deeply rooted.
New HST observations by the Spanish-American team are planned for the end of this year. The new data and the high-resolution imaging to be obtained by the NASA-ESA Cassini orbital mission expected to arrive at Saturn in mid-2004 will enable them and other scientists to learn whether the current wind pattern will persist or will change over the course of Saturn?s seasonal cycle. In either case, notes French, “these results will be important tests of our theoretical understanding of winds on the giant planets.”
Original Source: Wellesley College News Release
The accident investigator searching for the cause of the Columbia disaster said he was surprised by the force that foam tearing off of the shuttle’s fuel tank could cause to its wing. In a recent experiment, investigators fired a 760 gram chunk of foam at a fiberglass replica of the shuttle’s wing and tore open an important seal. Even more damage is expected when the next round of tests are performed with real shuttle wing parts, removed from Discovery, which are composed of reinforced carbon.