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MINERVA robot failed to land on asteroid Itokawa

The 1.3 pound (600-gram) MINERVA, whose name stands for Micro/Nano Experimental Robot Vehicle for Asteroid, was released by Japanese space probe Hayabusa Saturday toward Itokawa asteroid. The hopper robot was deployed at 3:24 p.m. Japan time, from a distance of about 180 feet (55 meters). But the robot have failed to land and has likely drifted away from the asteroid.

MINERVA was designed to hop gently across Itokawa’s surface. Three small TV cameras were supposed to take pictures, while temperature sensors would have provided insight into the texture of the soil.

Meanwhile, the Hayabusa mothership has safely returned to its home position, about 4 miles (6.4 kilometers) distant from the asteroid.

posted by: kyawoo at 20:59 | link | comments |
unmanned missions, asteroids

Hayabusa spacecraft ready to land on asteroid

Japan’s Hayabusa spacecraft is on track to attempt a sampling of asteroid Itokawa on November 19. In a rescheduled practice run on November 9, the craft has approached within 230 feet (70 meters) of the asteroid during a descent test that verified the probe’s guidance and navigation functions.

On November 4 landing rehearsal, an onboard navigation computer detected anomalous information during the practice run and the spacescraft backed away from the asteroid.

Mission officials are now prepared to carry out a landing at the "Muses Sea" site, performing sampling tasks on both November 19 and another touchdown on November 25.

Hayabusa is now ready for its historic attempt to gather and return asteroid specimens to Earth.

Not only is Hayabusa equipped to collect samples of the asteroid for return to Earth. A tiny robot will hop about Itokawa and relay pictures from the space rock’s surface.

Plans call for the probe’s return capsule carrying asteroid specimens to return to Earth in June 2007, landing by parachute in a remote desert spot in Woomera, Australia.

posted by: kyawoo at 10:54 | link | comments (1) |
unmanned missions, asteroids

Galileo satellite navigation program

The first of 30 satellites of the European Union’s Galileo satellite navigation program was unveiled Wednesday, one month before it will be launched into space.

The "Giove A" (acronym for Galileo In-Orbit Validation Element.satellite) will be launched in the second half of December. A second satellite named "Giove B" will be launched next spring. Two more satellites will be launched in 2008 to complete a testing phase that requires at least four satellites in orbit to guarantee an exact position and time anywhere on earth.

When finished, the $4.3 billion Galileo project will comprise 30 satellites and should end Europe’s reliance on the Global Positioning System, or GPS, which is ultimately controlled by the U.S. military. The Galileo program will be under civilian control.

Galileo, working alongside US GPS and Russian Glonass systems, will more than double the coverage of GPS, providing satellite navigation for a wide range of people from motorists to sailors to mapmakers.

By using Galileo, rescue services will be able to pinpoint the exact location of a car driver’s accident and will allow someone to find their way in an unfamiliar city using their mobile phone

posted by: kyawoo at 11:16 | link | comments |
space science

How Global Positioning System(GPS) works

GPS is based on a constellation of 24 solar-powered orbital satellites about 12,000 miles above the Earth. A GPS receiver on the ground seeks tracking signals from at least three satellites, then interpolates the data to establish latitude and longitude. If a device can pick up four or more signals, it can also determine a user’s altitude.

The GPS first satellite was launched in 1978 and the system was fully operational by the early 1990s. Originally, the military programmed the system for "selective availability," which gave the military 10-meter precision and civilians 100-meter precision. Selective availability was eliminated in 2000.

Users can get accurate location information across the globe, and most equipment can interpret it to provide speed, distance to a destination and even exact local sunrise and sunset times. Devices are installed in most large ships and aircraft, and the FAA has incorporated GPS as a key part of instrument flight. Many cars use it, and transit companies use it to track trucks and buses. Handheld devices are used by everyone from hikers to land surveyors. The military has adapted bombs with GPS receivers that can guide the weapons to targets.

With the military controls removed, GPS users can now get a precise latitude and longitude to within 10 to 15 meters. Advanced systems known as differential GPS and the Wide Area Augmentation System incorporate the use of stationary ground stations to interpolate signals, and can offer accuracy of 1 to 3 meters or better.

The U.S. Department of Defense continues to run the system, though other federal agencies such as the Department of Transportation have taken a role in upgrading and maintaining it.

(Source MSNBC)

posted by: kyawoo at 10:54 | link | comments |
space science

Space station crew takes walk to install new camera

In a 5 ½-hour space walk, ISS crew detached an old environmental probe that hadn’t worked in at least two years, and tossed it into the void about 210 miles above Earth. It should burn up in the atmosphere in 100 days. Debris left in orbit at altitudes under 300 miles typically burns up in the atmosphere within a few years.

In the case of the environmental probe, NASA engineers had feared its fasteners could come loose and damage the orbiting outpost if it wasn’t removed. To protect the space station, the probe was tossed in the opposite direction the station was moving. The probe had been installed in 2000 to collect data and measure the magnetic field around the station.

The crew, McArthur and Valery Tokarev, also used Monday’s space walk to install an external camera that will help future station astronauts add new segments to the lab.

The spacewalking pair, who arrived at the station in early October, helped each other into their spacesuits without the assistance of a third crewmember. Normally, one crewmember stays aboard while two others venture outside. But the space station crew has been reduced to two since the space shuttle Columbia disaster in 2003, and it has been left empty nine times during spacewalks since then.

Monday’s spacewalk was also delayed by an hour as they tried for the first time in two years to exit the U.S. airlock, which did not completely depressurize on the first try. When shuttle Discovery returned to orbit in July, it brought new U.S. spacesuits and a new heat exchanger was installed for the U.S. airlock.

posted by: kyawoo at 11:31 | link | comments |
space station

Mining the moon

The findings by Hubble Space Telescope support the potential existence of some unique varieties of oxygen–rich glassy soils in both the Aristarchus and Apollo 17 regions. They could be well suited for visits by robots and human explorers to learn how to live off the land on the moon.

Since the moon does not have a breathable atmosphere, and spacecraft have limited load capacities, harvesting oxygen from the soil may be critical for long-term human missions. Hubble found that the soil in the regions examined contained abundant amounts of ilmenite, a mixture of titanium, iron and oxygen.

Laboratory experiments on Earth have shown that applying certain chemical processes to terrestrial ilmenite can easily liberate oxygen and water. Water can then be turned into oxygen and hydrogen, which could also be used for rocket fuel.

The Hubble team examined three lunar sites, including the Apollo 15 and 17 landing sites, where soil chemistry is well-known. The third was the Aristarchus Crater region, a "geologic wonderland" that has piqued geologists’ interest for decades.

Aristarchus Crater is the brightest feature of the Moon’s near side, nearly twice as bright as most spots on the moon and visible to the naked eye. It’s just 25 miles (40 kilometers) across but more than 2 miles (3.2 kilometers) deep. At only 450 million years old, it is one of the younger major features on the moon.

More importantly, it sits in a region of the moon that scientists believe was once rocked by volcanic explosions and tectonic shifts. The 2-mile gouge exposes the historical record of what went on in the region, including the history of crust and mantle formation on a young satellite.

Aristarchus Crater was the planned landing site for Apollo 18, but no human or robot has ever set foot there, making it a likely target for the Lunar Reconnaissance Orbiter as it explores the lunar surface in 2008, according to current plans. Data from that mission, combined with Hubble’s observations, will help plan the location of future robotic and human missions.

posted by: kyawoo at 01:26 | link | comments |
moon

Asteroids mission on hold

A NASA mission to Vesta and Ceres, two of the largest asteroids in the solar system, has been placed in "stand down" mode. The ion-engine propelled Dawn mission is dedicated to investigating the two most massive asteroids known: . These two "baby planets" are very different from each other yet both offer tantalizing clues about the formation of the solar system. Dawn is designed to improve scientific understanding of how planets formed during the earliest epoch of the solar system.

Dawn has been on NASA’s books for liftoff in mid-June 2006. The decision to stand down appears related to budget-related measures and workforce cutbacks at the Jet Propulsion Laboratory (JPL) in Pasadena, California.

Dawn is a NASA Discovery-class mission, selected in December 2001. The goal of the Discovery program is to launch many smaller missions with fast development times, each for a fraction of the cost of NASA’s larger missions. Such spacecraft missions are designed to tackle important questions in science yet do it for a very modest cost.

The importance of spacecraft exploration of Ceres, for instance, was recently underscored by astronomical study of the object.

In September it was announced that observations of Ceres made by NASA’s Hubble Space Telescope revealed that the object may be a "mini planet" — perhaps loaded with large amounts of pure water ice beneath its surface.

posted by: kyawoo at 02:02 | link | comments |
asteroids

NASA’s top priorities

NASA’s top priorities are a replacement for the space shuttle and completing the international space station, NASA Administrator Michael D. Griffin said Thursday.

NASA has been developing the new crew exploration vehicle, which is intended to fly to the moon but also can replace the space shuttle when it goes out of service.

Delaying that work could result in the United States being out of the manned spaceflight business for a few years after the shuttle is retired, at the same time other nations are increasing their space programs, Griffin said.

In addition, he said, NASA is encouraging private industry to submit proposals to carry cargo and crew to the space station.

posted by: kyawoo at 02:52 | link | comments |
manned missions, space station

Martian dust is the big problem for manned missions

Martian dust poses as one of the biggest potential problems for manned missions to Mars, a NASA report said.

Compared to here, dust on Mars is thought to be larger and rougher, like the dust that covers the Moon. When Apollo astronauts landed there, they were covered in just a few minutes. Within hours, rough lunar dust had scratched up lenses and degraded seals.

If astronauts make the six-month journey to Mars, they’ll likely be expected to stay a while. That would give potentially hazardous dust plenty of time to accumulate in equipment, cause airlock malfunctions, or even infiltrate astronauts’ lungs.

Dust on Mars doesn’t just sit on the ground — it gets furiously swept about in dust devils and massive dust storms. Every once and a while, Mars experiences the "perfect dust storm," where powerful winds kick dust up into the atmosphere where it is spread around until it eventually clouds the entire planet.

posted by: kyawoo at 11:27 | link | comments |
mars

Scientists confirm helpful Moon mineral

Scientists using the Hubble Space Telescope have confirmed the presence of a mineral on the moon that might someday provide human explorers with life-sustaining oxygen and rocket fuel.

Researchers said Wednesday that they could detect ilmenite — a compound of iron, titanium and oxygen — at two old Apollo landing sites and one other region that astronauts never visited.

The telescope’s capacity to gather ultraviolet light is impossible to duplicate from beneath the Earth’s atmosphere. It offered a unique opportunity to use reflected light to remotely map minerals on the moon’s surface and learn something about its natural history.

Hubble safely made 60 brief exposures, snapped over three days during 12 orbits of the Earth.

posted by: kyawoo at 22:27 | link | comments |
moon