Posted on 08/09/2005 1:18:11 PM PDT by LibWhacker
NASA's twin Mars rovers continue to turn up intriguing new rock formations after a combined total of nearly 1120 Martian days on the planet.
After discovering relatively little, other than basaltic lava flows, during its first six months on the Red Planet, Spirit continues to make up for lost time as it ascends Husband Hill - unearthing clues to violence in the planet's youth.
Meanwhile, Opportunity is also experiencing a reversal of fortune on the other side of Mars. After trudging over desolate stretches of sand for about five months, it has finally reached an island of bedrock that appears unlike anything yet seen in the mission.
Spirit landed in the lava plains of Gusev Crater, getting off to a slow start in its mission. But since it began clambering up to higher ground in the Columbia Hills in July 2004, it has seen granular rocks with a mix of grain sizes. And recently it has seen the most extreme case of this from a spot about 20 metres below the summit of Husband Hill, which rises about 80 metres above the floor of Gusev Crater.
Plum pudding
About a week ago, Spirit paused to study an outcrop called Voltaire. The outcrop is made of large, often angular "pebbles" that appear to have a different composition than the finer-grained material in which they are embedded.
The rovers' chief scientist, Steve Squyres at Cornell University in Ithaca, New York, US, says the "plum pudding" composition hints at an explosive event such as a volcanic eruption or impact.
That view is strengthened by another rock that Spirit has been scrutinising for the last few days. Called Assemblee, it appears to be made of "cruddy glass" that may have been melted by such an event.
"The diversity of rock types is staggering," Squyres told New Scientist. He believes impacts may be to blame, pointing out that Spirit has previously uncovered rocks with high concentrations of nickel - an element found in many meteorites. The impacts would blast away different layers of the surface and jumble them together as they crashed down again. "You're basically throwing it into a blender," he says.
Early influences
But colleague Ray Arvidson of Washington University in St. Louis, Missouri, US, says there may be more to the story. "I think the crust is too complicated to have been produced by one process or one event," he says, adding that volcanic eruptions, impacts, wind and water all may have played a role. "These granular rocks were broken up, transported, put in place and cemented."
He says the Columbia Hills are even older than the approximately 3 billion-year-old volcanic plains that make up Gusev's floor and therefore contain clues about the events that shaped early Mars.
As Spirit continues towards the summit of Husband Hill and then proceeds down its southern slope, team members will compare the rocks to others they have studied. "If we see an even greater variety of rocks than we’ve observed so far, it will argue against one or two big events," Arvidson says.
Out to sea
On the other side of the planet, Opportunity is beginning to do some serious science of its own after a long stint of somewhat fruitless roaming. "Opportunity was the glamour rover for the first six months of the mission, but for the last five months, it has been trudging across a bleak plain of sand," says Squyres. "We felt like sailors who have been out to sea for months."
But within the last couple of days, the rover finally reached a little spot of bedrock - one of several scattered around the area. And it may prove worth the wait.
The rover used its rock abrasion tool to scrape the rock and found "blueberries” - broadly similar to those found in other places on Mars - that appear to have formed in the presence of water. But these have different size distributions and are not as spherical as those seen previously, suggesting the composition of the rock is different, says Squyres.
After studying this outcrop further, the team may send Opportunity farther south on Wednesday, towards an old, shallow crater called Erebus.
On Wednesday, NASA's Mars Reconnaissance Orbiter is also set to blast off to Mars. It will begin its work in November 2006, scanning the surface from a relatively low altitude of about 305 kilometres.
We've certainly gotten our moneys worth out of those two.
Another Mars ship is being prepped for lift off tomorrow on an Atlas 5.
Our space agency could be doing a better job of promoting this accomplishment to middle and high schools around the country.
Husband's Hill?? That would be named after a beer belly?
The little "engines" that could!
And some people say that American made vehicles aren't any good. What these things were supposed to last 30 days I think?
Sheesh, it's named after one of Columbia's commanders.
Its named after Rick Husband, the commander of the Columbia mission that broke up on re-entry.
Update from SpaceflightNow.com :
TUESDAY, AUGUST 9, 2005
1855 GMT (2:55 p.m. EDT)
Engineers are working to determine if there are any problems with a pair of Redundant Rate Gyro Units (RRGUs) aboard the Atlas 5 rocket that will launch the Mars Reconnaissance Orbiter. The units are part of the vehicle's flight control system.
The concern stems from an RRGU that failed factory testing while being readied for a future launch.
If the issue can be resolved promptly, liftoff will proceed on Thursday morning.
90 days.
I check their progress every single day.
Meanwhile, Opportunity is also experiencing a reversal of fortune on the other side of Mars. After trudging over desolate stretches of sand for about five months, it has finally reached an island of bedrock that appears unlike anything yet seen in the mission.
Amazing! They try to make what are the two most successful planetary probes in history sound hum drum, as if they border on failures, and this is the New Scientist.
How politically corrupt even the science magazines have become.
There is no future in space and they know it.
All they want is to retire with a government pension.
Yeah and remember the European Space Agency's Mars explorer - complete dud - no data whatsoever.
That's what they get for sending Le Probe, did Renault make that thing?
Wait a second, people around here told me NASA was incompetent. How did they manage to land two robots on the exact spot on Mars they chose, and explore it for more than a year?
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