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Space vegetables

"Space vegetables", bred by astronautical mutagenesis are now increasingly found on many of China’s dining tables, China Radio International reported. Astronautical mutagenesis is the science that mutate genes in the radiation of outer space,

Chinese scientists have been growing tomatoes the size of softballs, cucumbers as long as baseball bats and other outsize fruits and vegetables, using seeds that have been shot into space. The seeds are then exposed to seven types of extraterrestrial conditions, from zero gravity and cosmic radiation to subatomic particles. As these space veggies grow back on Earth, they are selected for desirable traits—bulk, appearance or certain nutrients—then bred through successive generations to ensure that the mutations are consistent.

Scientists at the Heilongjiang Academy of Agricultural Sciences in northeast China bred the first "space vegetable" after seven satellite experiments since 1987. The space experiments have resulted in a space bred tomato species in 2000 and a space green pepper species in 2002. The space vegetables are being planted in large areas across China. "Space tomatoes" are already grown on more than 4,900 acres, and "space peppers" on 34,600 acres.

Chinese scientists explain that astronautical mutagenic breeding technology alters the germ plasma of crop seeds, but it’s not just size that changes. Named "Yufan I" (space tomato) and with a fruit weight ranging from 250g to 800g, the new species features large fruit, delicious taste, sweet flavor, and rich vitamin C and sugar content. The space pepper, named Yujiao I, produces a fruit weighing 200g- 400g, characterizing large fruit, sweet and crispy taste, diseases resistance, and high yield. So far the two species have been extensively grown in most provinces. Experiments have confirmed a 20-day storage duration for Yufan I, or a week longer than conventional species. The space pepper is of a vitamin C content 20% higher than conventional species. At the same time, the space-bred vegetables have a shorter maturity period and an increased yield, or 15%-20% higher under the same conditions compared with local prevailing species.

A dozen or so Chinese firms are paying up to $45,000 a gram to place various flora aboard satellites and manned spacecraft. The long-term goal: to feed more people and help endangered species escape extinction. To date, nearly 3,000 botanical species—including garden vegetables, medicinal herbs and flowers—have been sent into orbit and brought back to Earth.

The Heilongjiang Academy of Agricultural Sciences is currently breeding "space cucumber" and "space eggplant," the report said.

posted by: kyawoo at 21:53 | link | comments |
space science

“Swift” hopes to unveil the secrets of gamma-ray bursts

Gamma-ray bursts, whivh can release as much energy in a few minutes as the Sun emits in its 10-billion-year lifetime, are among the most mysterious phenomena in the universe. They are the most powerful explosions the Universe has seen since the Big Bang. They come from all different directions of the sky and last from a few milliseconds to a few hundred seconds. They occur approximately once per day and are brief, but intense, flashes of gamma radiation. Yet what causes these mighty blasts is still unknown.

Gamma-ray bursts were first observed during the Cold War. In the late 1960s, US military satellites designed to look for clandestine nuclear tests picked up powerful bursts of radiation. Some even thought that they might be the product of Soviet nuclear tests on the Moon or on other planets. In fact, they came from deep space.

Scientists think that gamma-ray bursts are generated in two principal scenarios. In one scenario, a star collapses in on itself, giving birth to a black hole. Scientists also think the bursts can form when two neutron stars collide.

Some speculated that gamma-ray bursts could even be implicated in some extinctions in Earth history: Even if a gamma-ray burst went off in the centre of our galaxy, which is 30,000 light years away, it would still rival the Sun in terms of brightness.

As technology improved, astronomers were able to react more swiftly to these fleeting events and turn their telescopes towards them while they lasted, where they sometimes detected a fading optical glow from the same strange object.

On October 2000 four spacecrafts have detected the afterglow of the most distant gamma-ray burst ever recorded. They have revealed that the burst probably came from a gigantic dying star more than 30 times the mass of the Sun and which exploded when the Universe was about one tenth of its present age. The spacecrafts that detected this burst were the Ulysses spacecraft, the Near Earth Asteroid Rendezvous (Near-Shoemaker) craft, the Wind spacecraft, and the Italian Bepposax spacecraft.

The latest breakthrough began on March 2004 when the High-Energy Transient Explorer satellite (Hete) detected one of the brightest and closest gamma-ray bursts ever seen.

Located in the constellation of Leo, the 30-second burst, designated GRB 030329, outshone the entire Universe in gamma rays. Its optical afterglow was still over a trillion times brighter than the Sun over two hours later.

Currently, astronomers see about one or two gamma-ray bursts each month. But it is hoped that after the launch of a space probe called Swift, this could go up to about 100 bursts observed per year.

Swift, The $250m NASA probe with international cooperations, could lift off on 8 November 2004 at the earliest. Swift will orbit Earth in wait for a gamma-ray burst. Within about 20 seconds of a detection, Swift relays the position of the burst to the ground. As it relays this information, the spacecraft veers around to train its two onboard telescopes on the source, enabling precision measurements to be made. The spacecraft gets its name from the speed with which it has to move in order to observe the short-lived phenomena.

During its 2-year mission, Swift is expected to observe more than 200 gamma-ray bursts.

posted by: kyawoo at 10:02 | link | comments (1) |
astronomy, unmanned missions

Redesigning Space Shuttle

First, NASA will remove the foam insulation from the metal struts connecting the shuttle to its external fuel tank. And in case foam peels off from another part of the external tank, NASA has put sensors in Discovery’s wing panels to detect debris impacts and will install a digital camera for viewing the tank after it separates from the shuttle during the ascent.

Second, NASA is trying to devise ways to inspect the shuttle while it is in orbit and repair any serious damage that is discovered. The space agency began work on a sensor system located at the end of a 50-foot-long boom that would be attached to the shuttle’s robotic arm. Equipped with a laser ranger and a television camera, the system is designed to capture three-dimensional images the shuttle’s wings. But inspection effort faced "enormous challenges" because of the tight schedule for developing the sensor system. The plans for repairing damage are also incomplete: although the astronauts will be able to fill cracks in the wings and plug holes up to four inches wide, they will not be able to fix a gash as large as the six- to 10-inch breach that doomed Columbia.

NASA is preparing alternative measures that do not require as much technology development. Before Discovery docks with the International Space Station, the shuttle’s pilot will flip the craft so that astronauts in the station can take photographs of the heat-shield tiles on the shuttle’s underside from 600 feet away. The crew members may also conduct space walks to get a closer look. If they find a hole that cannot be fixed, the Discovery’s crew will remain in the station until the arrival of the shuttle Atlantis, which could be launched on a rescue mission within 45 days. The station should have enough supplies to support the astronauts for that long, assuming there are no breakdowns in critical systems such as oxygen generation or carbon dioxide removal.

NASA has also redesigned some other parts of the shuttle but not all the recommended fixes will be in place at the time of the first flight, limiting the kinds of missions the spacecraft can tackle

posted by: kyawoo at 12:53 | link | comments |
space shuttle

Final module to ISS ready

The final module of the International Space Station, Italian-built cupola, was delivered this month and awaits its flight at Kennedy Space Center. The small, round room with six windows around the sides and one on the top will be the last component installed on the station in 2009.

The cupola has a practical purpose: observation of spacewalks, robotic arm operations, Earth and space.

A number of station components including the cupola are awaiting the shuttles’ return to space which is expected to resume on May 2005 the earliest.

posted by: kyawoo at 12:46 | link | comments |
space station

Back to front switches blamed for Genesis crash

The most likely reason for thr failure of Genesis space probe is the switches designed to trigger its parachute were installed backwards. The switches on Genesis were meant to sense the braking caused by the probe’s high-speed entry into the atmosphere, and then initiate the deployment of the craft’s parachutes.

Lockheed Martin Astronautics is responsible for that fatal mistake. The aeronautics company declined to comment but said it was cooperating with Nasa.

Five years ago Nasa lost two of its missions to Mars thanks to seemingly trivial errors by the company.

posted by: kyawoo at 23:26 | link | comments |
unmanned missions

ISS and beyond

Today even the space enthusiasts are showing less interest in problem-plagued International Space Station(ISS) although it is part of President Bush’s vision for space exploration. The first priority in Bush’s vision is to return the shuttle safely to flight, and the second is to complete the ISS. 28 shuttle flights are needed to finish the station. The last few are just going to put spares on the station, effectively filling up the pantry.

But the big problem is once construction of the station is finished in 2010, the shuttle will be decommissioned. Although Soyuz can carry astronauts up to the station, and there are other resupply vehicles, Russians ships cannot carry as many cargo as shuttle. US industry is requested to find possibilities to resupply the station. But there is not yet clear answer.

If ISS is dead, what’s next?

There may be another station but it won’t be as complex and costly as ISS. There could be a space station that serves some commercial purpose: tourism, or perhaps materials processing.

posted by: kyawoo at 22:02 | link | comments |
space station

Ongoing Space Missions(7)

Voyager Interstellar Mission(VIM)

Mission Objective

To explore the outer limits of the Sun’s sphere of influence and possibly beyond. This extended mission is continuing to characterize the outer solar system environment and search for the heliopause boundary, the outer limits of the Sun’s magnetic field and outward flow of the solar wind.

Mission Characteristic

The VIM is an extension of the Voyager primary mission that was completed in 1989 with the close flyby of Neptune by the Voyager 2 spacecraft.Voyager 1 completed its planned close flybys of the Jupiter and Saturn planetary systems while Voyager 2, in addition to its own close flybys of Jupiter and Saturn, completed close flybys of the remaining two gas giants, Uranus and Neptune.

At the start of the VIM, the two Voyager spacecraft had been in flight for over 12 years having been launched in August (Voyager 2) and September (Voyager 1), 1977.

As of July 2003, Voyager 1 was at a distance of 13.3 Billion Kilometers (88 AU) from the sun and Voyager 2 at a distance of 10.6 Billion kilometers (70 AU).

Voyager 1 is escaping the solar system at a speed of about 3.6 AU per year, Voyager 2 is also escaping the

solar system at a speed of about 3.3 AU per year,

Both Voyagers are headed towards the outer boundary of the solar system in search of the heliopause, the region where the Sun’s influence wanes and the beginning of interstellar space can be sensed. The heliopause has never been reached by any spacecraft; the Voyagers may be the first to pass through this region, which is thought to exist somewhere from 8 to 14 billion miles from the Sun.

The Voyagers have enough electrical power and thruster fuel to operate at least until 2020. Eventually, the Voyagers will pass other stars. In about 40,000 years, Voyager 1 will drift within 1.6 light years (9.3 trillion miles) of AC+79 3888, a star in the constellation of Camelopardalis. In some 296,000 years, Voyager 2 will pass 4.3 light years (25 trillion miles) from Sirius, the brightest star in the sky . The Voyagers are destined—perhaps eternally—to wander the Milky Way.

Before leaving our solar systems, Voyagers made following major discoveries.

· Jupiter has complicated atmospheric dynamics, lightning, and auroras.

· Three new moons.

· Jupiter has rings.

· Io has active sulfur volcanoes, and these volcanoes have major effects on Jupiter’s magnetosphere.

· The Great Red Spot rotates once every six days, an it can survive almost indefinitely because it pulls in smaller eddies and adds their spin to its own.

Saturn:

· Saturn has over 1000 ringlets.

· Saturn’s rings have braids, kinks, and spokes which have not yet been explained.

· Seven new moons, including shepherd moons which keep the rings stable.

· Massive jet streams which change rarely.

· Saturn’s magnetic poles lie exactly on its true north and south poles.

· Titan, a moon, has a smoggy atmosphere, mostly composed of nitrogen, and at the surface has a density about 1.5 times Earth’s at sea level.

· Mimas, a moon, has a crater in it that covers about 25% of the surface.

posted by: kyawoo at 10:01 | link | comments |
astronomy, unmanned missions, sun

Monitoring atmospheric pollution from space

Envisat, launched in February 2002 by ESA, is making good progress in monitoring atmospheric pollution.Global air pollution map produced by Envisat proves clear just how human activities impact air quality.

Localised measurements of atmospheric nitrogen dioxide are carried out in many western industrial countries, but ground-based data sources are generally thin on the ground. Space-based sensors are the only way to carry out effective global monitoring. Nitrogen dioxide (NO2) is a mainly man-made gas, excess exposure to which causes lung damage and respiratory problems. It also plays an important role in atmospheric chemistry, because it leads to the production of ozone in the troposphere.

Nitrogen dioxide is produced by emissions from power plants, heavy industry and road transport, along with biomass burning. Lightning in the air also creates nitrogen oxides naturally, as does microbial activity in the soil.

Measurements from Envisat show very high Nitrogen dioxide concentration above north eastern China, across South East Asia and much of Africa. Ship tracks are visible in some locations: such as the Red Sea and the Indian Ocean. The smoke stacks of ships crossing these routes send a large amount of NO2 into the troposphere.

Envisat is the world’s largest satellite for environmental monitoring.

posted by: kyawoo at 13:02 | link | comments |
unmanned missions, earth

Smart Report Card of SMART-1

SMART-1(Small Missions for Advanced Research in Technology), launch on 27 September 2003, is doing well. The first phase, testing of primary solar-electric propulsion and of a miniaturised payload for cruise science experiments, telecommunications and spacecraft navigation, is successfully completed.

So far, the SMART-1 ion engine has operated for about 3300 hours and covered a distance of some 78 million kilometres, with only 52 kilograms of propellant. With this successful demonstration, SMART-1 is paving the way for future deep-space missions, using a solar- electric engine as primary propulsion.

For the first time, SMART-1 has used very short radio waves (called Ka band at 32 Gigahertz, with the KaTE instrument) to communicate with Earth. These enable far more information to be transmitted over deep space than the commonly used frequencies and in a shorter period of time.

Another SMART-1 achievement is the successful testing of a laser communication link experiment with ESA’s optical ground station in Tenerife, Canary Islands in February of this year. This laser technology, in which Europe is a leader, has already been applied to telecommunications satellites, but this was the first time a laser link had been used to communicate with a distant, rapidly moving spacecraft.

With all these achievements to celebrate after its first year in space, SMART-1 is now preparing for the next big milestone, the lunar capture which is expected to take place less than two months from now.

SMART-1 is Europe’s first lunar mission and will perform a detailed scientific study of the Moon.

posted by: kyawoo at 22:58 | link | comments |
unmanned missions, space science, moon

Return to Flight Journal

As it is preparing necessary steps that will put Space Shuttle again in earth orbit, NASA published a new series of monthly articles providing a behind the scenes look at ongoing Return to Flight activities. For more details, visit

http://www.nasa.gov/news/highlights/returntoflight.html

posted by: kyawoo at 09:10 | link | comments |
space science