Probe ends historic Mars mission

[War Profiteer]

BBC News

Spoiler :

Nasa says its Phoenix lander on the surface of Mars has gone silent and is almost certainly dead.

Engineers have not heard from the craft since Sunday 2 November when it made a brief communication with Earth.

Phoenix, which landed on the planet's northern plains in May, had been struggling in the increasing cold and dark of an advancing winter.

The US space agency says it will continue to try to contact the craft but does not expect to hear from it.

"We are actually ceasing operations, declaring an end to operations at this point," Phoenix mission project manager Barry Goldstein said at Nasa's Jet Propulsion Laboratory in Pasadena, California.

"However, since we've been surprised by the robustness of this vehicle, we're going to keep listening. As the orbiters fly overhead every two hours, we'll constantly turn on the radio and try to hail Phoenix to see if it is alive."

Fiery plunge

Launched from Earth in August 2007, the robot arrived on Mars on 25 May, landing further north than any previous mission to the Martian surface.

To make it down, the probe had to survive a fiery plunge through the Red Planet's thin atmosphere, releasing a parachute and using thrusters to control its descent.

The mission was scheduled to last just three months on the surface, but continued to work for more than five months.

During its ground operations, the robot dug, scooped, baked, sniffed and tasted the Martian soil to test whether it has ever been capable of supporting life.

Phoenix's major achievement was in becoming the first mission to Mars to "touch water" in the form of the water-ice it found just centimetres below the topsoil. Chunks of ice were seen to vaporise before the lander's cameras.

"This was quite a thrill for everybody and it has been the study of that ice that has kept us busy for the last five months," said Phoenix principal investigator Peter Smith of the University of Arizona in Tucson.

"We've excavated that ice, we know its depth, we know how it changes over the surface; we've seen different types of ice."

The spacecraft found the Martian soil to be mildly alkaline, quite different from the acidic soils seen by previous missions to other parts of the planet.

Other key results included the identification in the soil of calcium carbonate, which on Earth is a chief component of limestone rock.

Phoenix also detected sheet-like particles, which were probably clays of some kind.

The significance of both minerals is that they form only in the presence of liquid water - which could have supported life.

The lander also detected perchlorate (an ion containing chlorine and oxygen) which is an oxidising chemical and, on Earth, can sustain some microbes.

Phoenix even recorded snowfall; and took more than 25,000 pictures, from the panoramas of its Arctic landing site to the atomic scale images of dust grains delivered to its microscope.

"Phoenix has given us some surprises, and I'm confident we will be pulling more gems from this trove of data for years to come," said Peter Smith.

Phoenix was never expected to be a long mission. At its high latitude (68 degrees North), it was always destined to be starved of light as the Arctic winter deepened.

In the end, though, the demise of Phoenix was hastened by a dust storm which obscured the Sun's precious rays still further.

With so little energy getting into its solar panels, the batteries on Phoenix would have gone flat, preventing the robot from heating any of its systems in temperatures that were heading down to minus 100C.

Nevertheless, Nasa says its Mars Reconnaissance and Odyssey satellites will continue to listen for Phoenix for a further three weeks, until Solar Conjunction, when the Sun moves between Mars and Earth.

Phoenix had risen from the ashes of two previous failures.

In September 1999, the Mars Climate Orbiter spacecraft crashed into the Red Planet following a navigation error caused when technicians mixed up "English" (imperial) and metric units.

A few months later, another Nasa spacecraft, the Mars Polar Lander (MPL), was lost near the planet's South Pole.

Phoenix used hardware from an identical twin of MPL, the Mars Surveyor 2001 Lander, which was cancelled following the two consecutive failures.

Nasa's robot rovers, Opportunity and Spirit, continue to work at their equatorial landing sites five years after arriving at the planet.

The next mission to the surface of Mars is due to leave Earth next year. The Mars Science Laboratory is a "smart" rover that will be dropped on to the surface of the Red Planet by a rocket-powered "skycrane".

At almost three metres in length and weighing 850kg, MSL is considerably bigger than the current rovers.

The goverment is trying to hide the fact that aliens have terminated the lander. I SEE THROUGH THEIR LIES!

 

[Winner]

BTW, one of the findings - that the sand/dust on the surface looks like what we have on the sea floor here on Earth is IMHO very important. It's another proof that the northern plains on Mars are in fact the bottom of some prehistoric ocean.

 

[aelf]

In September 1999, the Mars Climate Orbiter spacecraft crashed into the Red Planet following a navigation error caused when technicians mixed up "English" (imperial) and metric units.

Imperial units for a scientific project?

 

[Winner]

Imperial units for a scientific project?

Just look how it ended

 

[Tee Kay]

I got a question: how deep were the prehistoric oceans on Mars? I read somewhere they were most likely several hundred metres deep.

 

[Winner]

I think nobody can tell until we land there, take some core samples, look for sediments etc. But AFAIK there are huge river basins visible from space. The fact that the ocean was salty means it was there for a long time.

I think that sooner or later we'll find evidence of life that existed there in the past.

 

[Winner]

BTW, imagine the climate on a planet with large bodies of water just on the northern hemisphere.

Climate on Earth is being stabilized by the free circulation of ocean water. On Mars, the southern hemisphere would have no oceans (only two inland seas - in Argyre and Hellas basins). The climate there would have been pretty rough, I guess. Also, the whole Tharsis plateau would be very high, something like Tibet Plateau and due to high humility its slopes would be covered by huge glaciers. There would be huge monsun-like seasonal rains, probably, like in Indian ocean on Earth.

But I'd really love take a raft to Noctis Labyrinthus

 

[@N1k1T0$]

Well Earth a couple of millions years ago also had a rough climate... I am not sure we can wait until Mars becomes another earth...

 

[Winner]

Well Earth a couple of millions years ago also had a rough climate... I am not sure we can wait until Mars becomes another earth...

It won't, not on its own.

The million euro question is "Is there enough water on Mars to form oceans again?"

 

[Bill3000]

I'm highly pleased at how long the craft lasted. It was supposed to last two months; it lasted almost seven.

 

[Thorbal]

Those pics are great!

 

[Eran of Arcadia]

RIP Phoenix, but good job.

 

[ArneHD]

It won't, not on its own.

The million euro question is "Is there enough water on Mars to form oceans again?"

I was under the impression that due to the lack of a magnetic field to protect it (the Marsian core is cold IIRC) it could not maintain a suitable atmosphere. It was essentially torn away by the solar winds.

But shouldn't this be in S&T?

 

[Fuzzz]

Those pics are great!

anyone can photoshop such pictures.

 

[Thorbal]

But they still look nifty .

 

[Thorvald of Lym]

A long life filled with accomplishment. Phoenix stands as inspiration for us all.

 

[Bigfoot3814]

I know what's on the surface of Mars.

A bunch of broken down NASA probes and satellites.

 

[RalofTyr]

Mars, per ratio, had more water than Earth did from 4.5 to 3.8 BYA.

Mars was a very wet world. Most of the water is probably still there, in permafrost.

 

[ParadigmShifter]

I reckon Beagle II tracked it down (while avoiding being detected) and killed it. Go UK!!!!

 

[ArneHD]

Mars, per ratio, had more water than Earth did from 4.5 to 3.8 BYA.

Mars was a very wet world. Most of the water is probably still there, in permafrost.

So Mars is in a "Snowball Mars" period?

As far as I know, a major increase in water (I'm using what I know about Earth here) should make the world relatively colder, while a major decrease in water should make the world relatively hotter, owing to greenhouse/icehouse effects. Now Mars should be colder than the Earth, since it is further from the Sun. As such a higher degree of surface water should make the whole planet go into a permanent Snowball.