[Home]
[Full version]
Images show threat the rovers face in giant Martian dust storm
Aug 30 ,Space & Earth science
The mighty Mars rovers Spirit and Opportunity continue to persevere in brutal conditions, as revealed in images of the sun they are sending home. The images show how opaque the Martian atmosphere has been in the face of a raging, two-month dust storm.
To understand the gravity of the storm, engineers and astronomers monitor the situation by examining the images of the sun and measuring the amount of dust or the opacity of the atmosphere.
Emily Lakdawalla of the Planetary Society assembled the mosaic of images, which were taken daily by the panoramic cameras (Pancams) on both rovers, Spirit and Opportunity. The images were calibrated by students in Cornell's MarsLab image-processing facility and made available through collaboration with Jim Bell, Cornell professor of astronomy and the principal investigator on the rovers' Pancam imaging team.
"Emily's mosaics are quite remarkable. They show a rover's-eye view of the storm getting worse, and this little light bulb we call the sun getting dimmer and dimmer and dimmer as the dust clouds built up," said Bell.
Since June, a massive dust storm has engulfed much of the Martian surface. The storm has put the rovers in danger, as they depend upon solar power to run during the day and to survive the harsh, cold Martian nights. As dust clouds block the sunlight and dust settles on the solar panels, the rovers' energy is depleted. Only wind can remove the dust, Bell said.
For the rover Spirit, the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., reports that even though the Martian sky above Gusev Crater is clearing, solar power levels remained fairly low and constant dust now appears to be accumulating on the solar panels. Between sol -- a Martian day -- 1283 (Aug. 12) and sol 1286 (Aug. 16), the atmosphere cleared by about 35 percent, leading to daily energy levels of about 300 watt-hours (the amount of energy needed to light a 100-watt bulb for three hours). Typical levels before the dust storms were around 700 to 900 watt-hours for the rovers.
On the other side of Mars, Opportunity, now waiting to enter Victoria Crater from the rim, is currently experiencing its lowest power levels to date. The sky was so dark in mid-July that less than 200 watt-hours of daily energy was available, according to JPL. But skies are slowly clearing, offering hope that the rover will be ready for a descent into the crater soon. Opportunity benefited from wind blowing some dust off solar panels on Aug. 22. Under gradually clearing skies, Opportunity's solar panels were producing about 300 watt hours daily by Aug. 24.
Source: Cornell University
Related stories:
NASA Plans to Visit the Sun
For more than 400 years, astronomers have studied the sun from afar. Now NASA has decided to go there. "We are going to visit a living, breathing star for the first time," says program scientist Lika Guhathakurta of NASA Headquarters. "This is an unexplored region of the solar system and the possibilities for discovery are off the charts."
Cassini sees collisions of moonlets on Saturn's ring
A team of scientists led from the UK has discovered that the rapid changes in Saturn's F ring can be attributed to small moonlets causing perturbations. Their results are reported in
Nature. Saturn's F ring has long been of interest to scientists as its features change on timescales from hours to years and it is probably the only location in the solar system where large scale collisions happen on a daily basis. Understanding these processes helps scientists understand the early stages of planet formation.
NASA Scientists Pioneer Method for Making Giant Lunar Telescopes
Scientists working at NASA’s Goddard Space Flight Center in Greenbelt, Md., have concocted an innovative recipe for giant telescope mirrors on the Moon. To make a mirror that dwarfs anything on Earth, just take a little bit of carbon, throw in some epoxy, and add lots of lunar dust.
Phoenix probe lands on Mars (Update 4)
NASA's Phoenix spacecraft landed in the northern polar region of Mars Sunday to begin three months of examining a site chosen for its likelihood of having frozen water within reach of the lander's robotic arm.
100 Explosions on the Moon
Not so long ago, anyone claiming to see flashes of light on the Moon would be viewed with deep suspicion by professional astronomers. Such reports were filed under "L" ... for lunatic.
Astrophysicists discover youngest known supernova in Milky Way
A North Carolina State University researcher has discovered the youngest known supernova in our galaxy. Estimated at a mere 140 years old, this celestial whippersnapper is at least 200 years younger than the next oldest known supernova, and its discovery may pave the way to a greater understanding of exploding stars.
NASA calls on APL to send a probe to the sun
The Johns Hopkins University Applied Physics Laboratory is sending a spacecraft closer to the sun than any probe has ever gone - and what it finds could revolutionize what we know about our star and the solar wind that influences everything in our solar system.
Solar games at Paranal
Cerro Paranal, home of ESO's Very Large Telescope, is certainly one of the best astronomical sites on the planet. Stunning images, obtained by ESO staff at Paranal, of the green and blue flashes, as well as of the so-called 'Gegenschein', are real cases in point.
[Home]
[Full version]