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Mission objectives of Space Shuttle Discovery

The major focus of Space Shuttle Discovery(officially named STS-114) will be testing and evaluating new Space Shuttle flight safety procedures.

The STS-114 crewmembers will deliver supplies to the International Space Station. Several elements will be carried in Discovery’s payload bay for delivery to the Station. These include the Multi-Purpose Logistics Module Raffaello, containing racks of supplies, food and water, and the Human Research Facility-2 rack. Also, the External Stowage Platform and a replacement Control Moment Gyroscope will be carried in Discovery’s payload bay.

During Mission STS-114, mission specialists will perform spacewalks to install the External Stowage Platform and the Control Moment Gyroscope onto the Station. They will unberth the logistics module and attach it to the Station to transfer several tons of supplies and equipment, including food and water, for use by the Expedition 11 crew.

posted by: kyawoo at 20:25 | link | comments |
space shuttle

Mars in deep freeze billion years ago

Scientists have long thought that Mars was once temperate enough for water to have existed on the surface and perhaps for life to have evolved there. But a new study by MIT and Caltech scientists gives this idea the cold shoulder. With the evidence turned up by the Mars Exploration Rovers, the Red Planet was once warm enough to have liquid water flowing on its surface. But that period happened more than 4 billion years ago, in fact.

Scientists analyzed the amount of argon in various Martian meteorites. As a noble gas, argon is not very chemically reactive, and because the decay rate is precisely known, geologists for years have dated rocks by measuring their argon content. However, argon is also known to "leak" out of rocks at a temperature-dependent rate. This means that if the argon remaining in the rocks is measured, an inference can be made about the maximum heat to which the rock has been subjected since the argon was first made. The cooler the rock has been, the more argon it will have retained.

posted by: kyawoo at 20:42 | link | comments |
mars

SOHO spacecraft discovered so many sun grazing comets

The Solar and Heliospheric Observatory (SOHO) spacecraft was engineered to watch solar eruptions and the ensuing space weather that sometimes bombards Earth. But early on in the mission, armchair astronomers figured out they could become comet discoverers using SOHO images.

SOHO is equipped with a device that blocks light from the Sun’s main disk so detailed images can be made of the solar atmosphere and surrounding space.

Before SOHO was launched, only 16 sun grazing comets had been discovered by space observatories. In January 2005, mission officials projected SOHO’s 1,000th comet would be found soon.

The comets found with SOHO are very near the Sun, otherwise they wouldn’t appear in the craft’s field of view. These Sun grazers, as they are called, often escape other detection because they cannot be spotted amid the overwhelming glare.

SOHO is a joint effort between NASA and the European Space Agency. It has accounted for about half of all comet discoveries, through history, in which orbits have been calculated.

posted by: kyawoo at 11:56 | link | comments |
unmanned missions, comets

Russia space programme

Russia government approved space programme for next 10 years.

Russia will develop a reusable spacecraft to replace the ageing Soyuz manned launch vehicle. Russia also wants to start experiments to test whether it is possible for humans to make the flight to Mars.

But the new 10-year budget, reported to be about 300 billion roubles ($10.50 billion), is less than the US spends on space in a year.

posted by: kyawoo at 11:11 | link | comments |
space science

Shuttle launching posponed due to faulty sensors

The launch of the Discovery space shuttle has been delayed for several days because of technical problems with one of four low-level fuel sensors, or engine cut-off sensors, on the hydrogen fuel tank.

And even then, the flight will only go ahead if engineers are "lucky" in isolating the problem which caused Wednesday’s launch to be aborted. Shuttle engineers are preparing to enter the vehicle’s aft (rear) section to check a suspect electronics box.

The launch countdown has been stopped while hundreds of engineers working in 12 teams across the US hunt the source of a problem Sensors warn the shuttle computers if the tank is about to run dry, allowing the computers to shut down the three main engines safely. If the sensors gave a false "dry" reading during ascent, the engines could cut out before the shuttle reached orbit, forcing the vehicle to abort and carry out an emergency landing.

The current launch window runs until the end of July, after which Discovery would have to wait until September to get airborne.

posted by: kyawoo at 08:00 | link | comments |
space shuttle

Planet with 3 suns

Scientists have discovered a Jupiter-sized planet in the constellation Cygnus that is 1,500 times the size of Earth and has three suns.

The suns are as close to one another as the one in our own solar systerm is to Saturn, a distance about 10 times that between the Earth and its sun. The discovery, scientists say, could shake up theories of how planets are formed and open the prospect that there may be several more planets than had been previously assumed. The three stars collectively make up a system known as HD188753, and are about 149 light years from Earth.

posted by: kyawoo at 20:23 | link | comments |
astronomy

Evidence Temple-1 comet formed gradually

The plume of debris that spilled from the belly of Temple-1 comet after it collided with Deep Impact space probe is as fine as talcum powder, suggesting the comet formed gradually, scientists said Friday.

Soon after the 820-pound probe hit the surface of Tempel 1, scientists detected evidence of hot water, carbon dioxide and organic substances spewing from the comet. The high-speed collision produced two flashes of light and hurled a plume of fine, powdery dust from the pit of the comet thousands of miles into space.

Comets are believed to be abundant in water and partially responsible for replenishing Earth’s oceans after asteroids bombarded the planet during its early years and wiped out its water source.

But astronomers were surprised to find a lack of water vapor after the collision. Preliminary findings by a science instrument aboard a NASA satellite in Earth orbit showed Tempel 1 released about 550 pounds of water per second, similar to the amount before the impact, suggesting the comet contain more dust than ice.

posted by: kyawoo at 20:20 | link | comments |
comets

Space Shuttle will be closely watched

A total of 107 cameras will be trained on Space Shuttle Discovery during its launch. From lift-off and for about 30 seconds, while the shuttle is still in view, the cameras should be able to spot falling pieces of foam or ice as small as 2.5 centimetres across. If there is a problem, the cameras should be able to pinpoint where the debris strikes the orbiter and where it came from on the tank to within 15 cm.

Two WB-57 aircraft will also snap pictures as they circle the site during launch. And radar will track the launch from two ships - the same vessels that retrieve the solid rocket boosters from the Atlantic Ocean - and from a 15-metre radar dish on a nearby island.

The shuttle itself will also be used to search for possible damage. Temperature sensors and accelerometers have been added to the wings to detect heat and impacts. And once in orbit, astronauts will meticulously inspect the orbiter using the shuttle’s upgraded robotic arm.

The 15-metre arm is not long enough to reach underneath the orbiter. So after the Columbia accident, NASA extended it with a 15-metre boom built from spare parts for the arm. The boom is fitted with a video and laser system.

Astronauts will use it to scan the leading edges of the wings, the nose cone, and the underside of the orbiter - where debris from the external tank would probably strike. The data will then be made into 3-D images of the orbiter’s heat shield.

Astronauts will operate the boom on Discovery from inside the shuttle and must avoid it hitting the orbiter. They will monitor what is going on by looking out of the windows, and viewing images from cameras on the arm. "Probably the most difficult part is when we’re doing the port wing because there are some positions there where we don’t have as good views as we would like," says veteran astronaut Andy Thomas, one of three shuttle crew who will operate the boom.

The boom manoeuvre’s timing - on the second day of the flight - will add to its difficulty. The task requires good hand-to-eye co-ordination but the astronauts will still be adjusting to life in microgravity and might suffer from bouts of space sickness.

Astronauts aboard the International Space Station will also inspect the orbiter, with the shuttle flipping nose-over-tail as it approaches the docking bay to provide a better view.

posted by: kyawoo at 22:25 | link | comments |
space shuttle

Deep Impact

Comets are among the most primitive objects in the solar system, containing beneath their surface relatively unchanged chemical and physical records from the time the system was formed some 4.6 billion years ago — clues to the primordial soup from which life on Earth eventually emerged. By creating a large crater in the elongated comet — a mass of ice, rock and dust — and then to observe the crater’s development, measurements and ejected matter. Scientists believe they can reveal some secrets of comets and the solar system.

So, they sent a $333-million U.S.spacecraft named Deep Impact to hit a comet called Temple-1 and the 37,000-kph collision created the biggest Fourth of July blast ever. When the cosmic smash-up occurred on Monday, some 130 million kilometers from Earth, scientists and people around the world leapt to their feet in rapturous applause.

The impactor was destroyed when it hit the comet but its traveling companion, Deep Impact’s fly-by craft, is recording scientific data and sending them back to earth.

Even as the data begins filtering back to Earth, the Deep Impact mission has already answered a number of scientific questions. The comet is not so fluffy that it would completely disintegrate at time of impact.

This was a violent event that really dominated the comet’s appearance after the impact. The brightness increased over 10 minutes, then leveled off. It is still very visible. Now scientists are eager to see the newly exposed surface.

Scientists hope Deep Impact will have its greatest impact after its data are fully analyzed.

posted by: kyawoo at 21:27 | link | comments |
comets

Budget cut for unmanned missions

NASA.s new focus on human exploration—including the resumption of space shuttle flights scheduled for this month—is pulling funds from the unmanned spacecraft that study Earth, the sun and the outer reaches of the solar system.

In addition to devoting 40 percent of its $16.5-billion budget to the shuttle and the International Space Station, NASA has earmarked $753 million for the design of the Crew Exploration Vehicle, which will carry astronauts into orbit after the shuttle is retired in 2010. To help pay for this effort, the agency has proposed deep cuts to its Earth-Sun System Division, which operates Voyagers 1 and 2 and a dozen other probes that have completed their primary missions but are still yielding valuable data. Ordered to lop $20 million from the $75-million budget for the missions, the division will hold a review this fall to determine which spacecraft must be sacrificed. Potential victims include solar observatories (such as Ulysses and TRACE) as well as probes that investigate space weather around Earth (such as Polar, FAST, Geotail and Wind).

posted by: kyawoo at 21:28 | link | comments |
unmanned missions