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NASA administrator Michael Griffin said Friday he would proceed with planning for a shuttle visit to the Hubble Space Telescope, despite a two-month delay in the fleet’s return to flight.
Griffin declared a proposed robotic servicing mission to the Hubble Space Telescope "off the table." He told reporters he would proceed with planning for the Hubble servicing mission on the presumption that it will pass muster following return-to-flight technical reviews.
The aging telescope, launched in 1990, is at risk of equipment breakdowns that will make it inoperable. Of particular concern are Hubble’s gyroscopes, which keep the telescope properly positioned for celestial observations and its batteries.
Engineers and managers involved in planning a shuttle servicing mission to Hubble will be meeting soon at the Goddard Space Flight Center in Greenbelt, Md., to resume work, Griffin said.
The launch of space shuttle Discovery was posponed from May until July because of safety concerns.
The shuttle was to take off May 22, a delay from May 15. A July launch will have to be made between the 13th and 31st for conditions to be favorable. The launch window for Discovery is limited because NASA has committed to daytime launches for the next two missions to provide ideal lighting conditions for upgraded cameras that will image the shuttle as it climbs into orbit.
There are concerns about the external fuel tank and the risk of falling debris.A piece of fuel-tank foam insulation was blamed for the disintegration of the shuttle Columbia over Texas as it was returning from space February 1, 2003, killing all seven astronauts aboard.
Comets are observed to come to the solar system from all directions, therefore the place where the comets come from is thought to be a giant sphere surrounding the solar system. This sphere is called the Oort cloud after Jan Oort who suggested its existence in 1950. Location of Oort cloud is as far away as 100,000 AU. (An AU is the distance from the earth to the sun and is equivalent to about 100,000,000 miles.)
Within the cloud, comets are typically tens of millions of kilometers apart. They are weakly bound to the sun, and passing stars and other forces can readily change their orbits, sending them into the inner solar system or out to interstellar space. The total mass of comets in the Oort cloud is estimated to be 40 times that of Earth.
Some comets come from a closer region called the Kuiper Belt, which is located past the orbit of Pluto. Kuiper Belt objects are the source of the Jupiter family, a group of comets whose orbits take them between Jupiter and the sun in a short period of time (3-10 years). Comet Shoemaker-Levy 9, which became trapped in a gravity well and plunged into Jupiter’s atmosphere in 1993, may have been a member of the Jupiter family of comets.
A group of engineers was honored Tuesday for their brilliant jobs done 35 years ago.
On its way to the moon, Apollo-13 was crippled by an oxygen tank that overheated and exploded, raising concerns the carbon dioxide the astronauts expelled from their lungs as they breathed would eventually kill them. Two of Apollo’s three fuel cells, a primary source of power, also were lost. Astronauts Jim Lovell, Fred Haise and Jack Swigert would have died without the engineers’ quick thinking.
Engineers on the ground had to figure out a solution, and then tell the astronauts how to make the fix.
Ed Smylie, who oversaw NASA’s crew systems division in 1970 and is now an aerospace consultant, was glad the engineering side of the mission was being recognized.
Smylie said he was at home watching television when he learned there was a problem aboard Apollo 13. Within minutes, he was at the space center trying to come up with a solution.
The astronauts had moved to the lunar module from the command module to conserve power for the emergency return to Earth. They had lithium hydroxide canisters to cleanse their spacecraft of carbon dioxide, but some of the backup square canisters were not compatible with the round openings in the lunar module.
Smylie and other engineers soon had a proposed solution to retrofit the canisters, but it took a day or two to build a mock-up and get instructions to the crew.
Among the biggest concerns was whether the astronauts had duct tape, Smylie said. He later learned duct tape was commonly used on the spacecraft to clean filters and for other tasks.
Astronaut Fred Haise said the device was tricky to build, but it worked.
"Had someone not figured that out, we wouldn’t have survived. ... We had confidence the right people had been brought in and would work it out," he said.
Since the inception of the space program, NASA has entrusted the delicate task of bringing two spacecraft together in orbit only to its skilled astronauts.
But as the agency plans to replace the space shuttle, it is considering using an autopilot for rendezvous and dockings and tested it on 2005 April 16. The $110 million mission, classified as high-risk because of its automated controls and relatively low budget, was intended to help lay the groundwork for future projects like robotic delivery of cargo to space shuttles and automated docking and repair between spacecraft in orbit. But the mission ended early when the computer-driven craft detected a fuel problem.
The experimental DART spacecraft — short for Demonstration of Autonomous Rendezvous Technology — had moved to within 300 feet of the satellite orbiting 472 miles above the Earth. The spacecraft was supposed to have maneuvered around the satellite, getting as close as 15 feet, for another 12 hours. After the problem arose, the 800-pound craft began coasting and eventually disintegrated in orbit.
Scientists called the mission a partial success because it demonstrated that an entirely computer-controlled craft could find a satellite in space.
The Kuiper Belt is a ring of a few hundred chunks of ice, strung like a dirty diamond necklace in the vastness of space beyond Neptune. It is located in the region about 12 to 15 billion kilometers (7.5 billion to 9.3 billion miles) from our Sun.
Kuiper Belt Objects(KBOs) are very faint, and extremely hard to study from the Earth. Even the powerful cameras of NASA’s Hubble Space Telescope can only produce rough images.
Most of the detected "KBOs" are small, with diameters typically around 62 mi/100 km. The first KBOs were discovered only in 1992 but its existence was hypothesized since 50 years ago.
In 1950, Dutch astronomer Jan Oort proposed that comets came from a vast shell of icy bodies about 50,000 times farther from the Sun than the Earth. The region Jan Oort was refering was later called Oort cloud. A year later astronomer Gerard Kuiper suggested that some comet-like debris from the formation of the solar system should also be just beyond Neptune. This notion was reinforced by the realization that there is a separate population of comets, called the Jupiter family, that behave strikingly different than those coming from the far reaches of the Oort cloud. Besides orbiting the Sun in less than 20 years (as opposed to 200 million years for an Oort member), the comets are unique because their orbits lie near the plane of the Earth’s orbit around the Sun. In addition, all these comets go around the Sun in the same direction as the planets.
Kuiper’s hypothesis was reinforced in the early 1980s when computer simulations of the solar system’s formation predicted that a disk of debris should naturally form around the edge of the solar system. According to this scenario, planets would have agglomerated quickly in the inner region of the Sun’s primordial circumstellar disk, and gravitationally swept up residual debris. However, beyond Neptune, the last of the gas giants, there should be a debris-field of icy objects that never coalesced to form planets.
The Kuiper belt remained theory until the 1992 detection of a 150-mile wide body, called 1992QB1 at the distance of the suspected belt. Several similar-sized objects were discovered quickly confirming the Kuiper belt was real.
The most recent exciting discovery to come out of the Kuiper Belt is "Quaoar" (Kwa-whar), officially known as 2002 LM60, a frozen world orbiting our sun about a billion miles beyond the orbit of Pluto. The tiny world’s diameter is 1,300 km (800 miles) - about half the size of Pluto. It is the largest of the more than 500 Kuiper Belt Objects discovered in the last decade. Quaoar/2002 LM60 orbits our Sun in a near circle, more so than any of the other planets or bodies in our solar system.
NASA’s proposed New Horizons spacecraft could fly through Kuiper belt in 2026.
When the Space Shuttle Discovery returns to flight, it will have a special escort. The pair of high-flying chase planes, carrying on-board video imaging systems, dubbed the WB-57 Ascent Video Experiment (WAVE), will provide NASA with extra "eyes in the sky" to watch Discovery.
The system will capture detailed images of how the Space Shuttle behaves, as it climbs toward orbit. During the launch, the jets will keep pace with Discovery, flying at a distance of 15 to 20 miles. The WAVE systems will track the Shuttle for approximately 150 seconds, from liftoff to separation of the Solid Rocket Boosters, the power systems that provide the main thrust to lift Discovery off the pad.
NASA has approved up to 18 months of further operations for its twin Mars Exploration Rovers - Spirit and Opportunity - which were originally meant to carry out missions lasting just three months. They both have found signs of a watery past on Mars since landing on the Red Planet in January 2004.
The rovers are showing signs of wear - for example, the teeth on Spirit’s rock grinding tool seem to have worn down - but otherwise remain in good shape.
The original mission cost $820m and the two previous mission extensions cost $15m. Nasa officials have declined to say how much the third will cost.
For the first time ever, the public have a chance to see at the University of Wisconsin-Madison a tiny speck of zircon crystal that is barely visible to the eye is believed to be the oldest known piece of Earth at about 4.4 billion years old. With the aid of a microscope, anyone has a chance to check out the tiny grain, which measures less than two human hairs in diameter.
Analysis of the object in 2001 by John Valley, a UW-Madison professor of geology and geophysics, startled researchers around the world by concluding that the early Earth, instead of being a roiling ocean of magma, was cool enough to have oceans and continents — key conditions for life.
Valley found that the planet had cooled to about 212 degrees Fahrenheit (100 degrees Celsius) less than 200 million years after it was formed. Before the research, the oldest evidence for liquid water on the planet was from a rock estimated to be much younger — 3.8 billion years old.
After the festivities the object will return to its native Australia with Simon Wilde, professor at Curtin University of Technology in Perth, Western Australia, who made its discovery in 1984. The sample will eventually be put on display at a natural history museum in that country.
A European Space Agency mission to Mars would leave Earth in June 2011 and arrive at the Red Planet in June 2013.
The 500-million-euro mobile laboratory would "sniff" the air for signs of biology and listen to the ground for evidence of Marsquakes.
The likely final mission will emerge and evolve from concepts that are already on the table and have been debated for some time.
Although the final architecture of the mission will not become clear for several months, there are certain "must haves" scientists have said should be built in to any lander - and these go to technologies that Europe feels will complement any instrumentation the American plan to send on their future rovers. The must haves include:
· a drill or "mole", such as the one designed for Beagle 2, that could go under the oxidised surface of Mars to find water and help investigate the subsurface geochemistry
· "life-marker" experiments that would analyse the soil, rocks and gases in the atmosphere for signs of biological activity. Life traces would have specific chemical "signatures"
· a seismometer to detect Marsquakes and other geological activity.
Esa’s last landing attempt, Beagle 2, went missing without a trace in 2003.
Mo'nonymous on New companion of Nep...
Mo'nonymous on New companion of Nep...
Mo'nonymous on New companion of Nep...
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