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Spirit rover attempting spot the ghost of the Halley’s comet

NASA’s rover Spirit has turned its gaze away from the Martian rocks at its wheels and looks skyward in an attempt to spot a meteor shower. Mars is currently passing through debris left by Halley’s comet and the Spirit team hope the rover might spot bright streaks left in the sky as the Red Planet spins through the ghost of the comet’s tail.

The rover’s panoramic camera has so far spotted several streaks in the Martian night sky. However, these may turn out to be the result of cosmic rays. Scientists on the ground are now poring over images, trying to see if the orientation of the streaks is consistent with the comet’s path.

He adds that the team hopes to gain insight into the amount of meteoritic debris that hits Mars during a shower. The observations could also tell scientists more about the chemical effects of meteors in an atmosphere replete with carbon dioxide – the modern Martian atmosphere may be similar to that of early Earth.

Earth passes through Halley’s trail every May and October, resulting in two visible meteor showers. The showers are named the eta Aquarids and Orionids after regions of the sky in which they appear.

It is the first time that Spirit has turned its attention to the sky to try and spot a meteor shower. But the rover previously spotted a meteor flying through the atmosphere by chance, on 7 March 2004. Based on the meteor’s trajectory and speed scientists later concluded that it was probably caused by debris from the comet Wiseman-Skiff.

Spirit also celebrated its first Martian anniversary on 20 November. It has spent one full Martian year – 687 Earth days – roaming across Gusev Crater, even though it was only designed to last about 90 Martian days. Each Martian day lasts only 39 minutes longer than a day on Earth.

Spirits twin rover, Opportunity, will celebrate its first Martian anniversary on 12 December. Since arriving on Mars it has covered 6.4 kilometres of terrain. Opportunity is currently heading for the western rim of Erebus Crater, to investigate an unusual two-textured rock outcrop 150 metres inside the crater.

posted by: kyawoo at 20:01 | link | comments |
unmanned missions, mars, comets

Hayabusa successfully landed on the asteroid

Japanese space probe Hayabusa has successfully landed on the asteroid on Sunday for about half an hour. It landed on the asteroid within about 100 feet of the landing target. However, the probe failed to collect material and then departed.

The probe had moved as far as 62 miles from the asteroid but was now getting closer for a second attempt

The asteroid is named after Hideo Itokawa, the father of rocket science in Japan, and is orbiting the sun between Earth and Mars. It is 2,300 feet long and 1,000 feet wide and has a gravitational pull of only 1/100,000th of Earth's, which makes landing a probe there difficult.

 

posted by: kyawoo at 19:33 | link | comments |
unmanned missions, asteroids

Cracks found in shuttle fuel tank foam

A total of nine cracks — only two of them visible on the surface —were found in shuttle fuel tanks, in the same area where foam popped free during the July launch of the Discovery orbiter.

 Shuttle program manager Wayne Hale added that, while the engineering assessment of the cracks is still pending, it appears that the thermal and pressurization changes involved in fueling the tank during two tests may be one potential cause.

posted by: kyawoo at 06:32 | link | comments |
space shuttle

Hayabusa fails to land on asteroid

Hayabusa, the Japanese research probe failed to touch down on an asteroid Sunday after maneuvering within meters (yards) to collect surface samples, Japan’s space agency said. The probe was on a mission to briefly land on the asteroid, collect material, then bring it back to Earth.

When Hayabusa was 40 meters (130 feet) above the asteroid Itokawa, it dropped a small object as a touchdown target, then descended to 17 meters (56 feet), said officials from Japan’s space agency, JAXA. At that point, ground control lost contact with the probe for about three hours, the officials said.

The exact location of the probe was unknown, Horiguchi said, but it was believed to be within 10-100 kilometers (6-60 miles) of the asteroid. Officials plan to make a second landing attempt on Friday.

Examining asteroid samples is expected to help unlock secrets of how celestial bodies were formed because their surfaces are believed to have remained relatively unchanged over the eons, unlike those of larger bodies such the planets or moons, JAXA said.

A NASA probe collected data for two weeks from the Manhattan-sized asteroid Eros in 2001, but did not return with samples.

posted by: kyawoo at 11:08 | link | comments |
unmanned missions, asteroids

Women are in bed - for space science research

A joint study by the European Space Agency, the French space agency CNES, the Canadian Space Agency and NASA is being carried out to learn how to protect women astronauts from the dramatic physical side effects of weightlessness.

The female volunteers are required to stay in bed for 60 days. They are not allowed to stand or sit up, ever, and there’s a 24-hour surveillance camera to make sure. Each showers lying down and even jogs in bed, strapped in to a vertical treadmill that makes people feel they are racing up a wall.

Twelve women completed the study six months ago; the rest are now in bed at a hilltop research center overlooking the red tile roofs of Toulouse, in southwest France. Day and night, in comfy T-shirts and pajamas, they lounge on hospital beds tilted so their feet are 6 degrees higher than their heads — provoking a physical reaction akin to weightlessness.

Bed-rest studies are frequent in space study, and testing nutritional supplements and exercise routines is important to keep astronauts fit for longer missions. A manned trip to Mars, for example, would expose astronauts to weightlessness or reduced gravity for up to three years. When they land on the Red Planet, they have to be strong enough to work.

Few of the studies have focused on women, however, as 10 times as many men than women have been astronauts, Jost said. Today, nearly 21 percent of NASA’s astronauts are women.

One question mark is the ideal level of exercise to protect women from bone loss, keeping in mind that strenuous workouts can modify women’s complex hormonal systems and cause their periods to stop.

In the first group of bed-rest volunteers, all lost bone mass at first, but after six months they are back to normal, said Dr. Arnaud Beck, the coordinator in charge of medical ethics.

One surprise find: Past research from short-term missions suggested that women astronauts are more susceptible to dizziness after returning home. But that did not prove true during tests in Toulouse. One possibility is that the difference may fade or disappear during long-term missions.

Volunteers came from across Europe to spend 100 days at the center, more than half of it in bed. They are paid $17,500 to give constant blood samples, submit to electrocardiograms and take tests for bone density and muscle strength. Their urine — all of it — is stored and analyzed. The women also receive counseling and are meticulously cared for. Scientists will check up on them for three years.

posted by: kyawoo at 09:57 | link | comments |

Planet with Three Suns

A Jupiter-class planet orbiting a triple-star system known as HD 188753 was found, according to a report In the July 14 issue of Nature. The three stars are about 149 light-years from Earth and are about as close to one another as the distance between the sun and Saturn.

In other words, a viewer there would see three bright suns in the sky. In fact, the sun that the planet orbits would be a very large object in the sky indeed, given that the planet’s "year" is only three and a half days long. And it would be yellow, because the main star of HD 188753 is very similar to our own sun. The larger of the other two suns would be orange, and the smaller red.

The new type of planet is referes as "Tatooine planets," because of the similarity to Luke Skywalker’s view of his home planet’s sky in the first Star Wars movie.

The fact that a planet can even exist in a multiple-star system is amazing in itself. Binary and multiple stars are quite common in the solar neigborhood, and in fact outnumber single stars by some 20 percent.

Researchers have found most of the extrasolar planets discovered so far by using a precision velocity technique that is easier to employ on studies of single stars.

posted by: kyawoo at 10:38 | link | comments |
astronomy, planets

Spitzer Captures Cosmic Mountains of Creation

The majestic image featuring star-forming clouds of cool gas and dust that have been sculpted into pillars by radiation and winds from hot, massive stars was aptured by Spitzer infrared telescope.

The Spitzer image, which can be found at http://www.spitzer.caltech.edu/Media, shows the eastern edge of a region known as W5, in the Cassiopeia constellation 7,000 light-years away. This region is dominated by a single massive star, whose location outside the pictured area is "pointed out" by the finger-like pillars. The pillars themselves are colossal, together resembling a mountain range. They are more than 10 times the size of those in the Eagle Nebula.

The largest of the pillars observed by Spitzer entombs hundreds of never-before-seen embryonic stars, and the second largest contains dozens.

Spitzer was able to see the stars forming inside the pillars thanks to its infrared vision. Visible-light images of this same region show dark towers outlined by halos of light. The stars inside are cloaked by walls of dust. But infrared light coming from these stars can escape through the dust, providing astronomers with a new view.

The W5 region and the Eagle Nebula are referred to as high-mass star-forming regions. They start out as thick and turbulent clouds of gas and dust that later give birth to families of stars, some of which are more than 10 times more massive than the sun. Radiation and winds from the massive stars subsequently blast the cloudy material outward, so that only the densest pillar-shaped clumps of material remain. The process is akin to the formation of desert mesas, which are made up of dense rock that resisted water and wind erosion.

According to theories of triggered star formation, the pillars eventually become dense enough to spur the birth of a second generation of stars. Those stars, in turn, might also trigger successive generations. Astronomers do not know if the sun, which formed about five billion years ago, was originally a member of this type of extended stellar family.

posted by: kyawoo at 11:08 | link | comments |
astronomy

Hubble Telescope captures images of the stars being born

Hubble Space Telescope reveals stars in the process of being born amid a fantastic scene of wispy space structures and intense radiation. The stars have yet to condense into small enough packages to trigger thermonuclear fusion, which is what powers stars, but they appear to be on the verge.

The setting is 210,000 light-years away in the Small Magellanic Cloud (SMC), a satellite galaxy of our Milky Way. Energetic outflows and radiation from hot young stars erode the dense outer portions of the star-forming region, formally known as N66, exposing new stellar nurseries.

The Small and Large Magellanic Clouds are diffuse irregular galaxies visible to the naked eye in the southern hemisphere. They are two smallish satellite galaxies that orbit our own Milky Way Galaxy and will eventually merge with it.

posted by: kyawoo at 10:36 | link | comments |
astronomy

Stereo View of the Sun

The two Solar TErrestrial RElations Observatory (STEREO) spacecrafts are set to launch in Spring 2006, STEREO is the first mission to image the sun and solar wind in 3-D. This new view is critical to improving our understanding of space weather and its impact to space and on Earth systems.

During its two-year mission, the two nearly identical spacecraft will explore the origin, evolution, and interplanetary consequences of coronal mass ejections (CMEs), the most violent explosions in our solar system. When directed at Earth, these billion-ton eruptions can disrupt satellites, radio communications, and power systems. In addition, energetic particles associated with CMEs are a serious hazard to spacecraft and astronauts.

posted by: kyawoo at 21:36 | link | comments |
unmanned missions, sun

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