Immense ever-frozen crater is Martian 'winter wonderland'
Tuesday, December 25, 2018, 3:20 PM - An ever-frozen 'winter wonderland' crater, a new science instrument deployed, and continued silence from a venerable explorer. Here's What's Up... on Mars!
For a barren, supposedly lifeless planet, Mars - the fourth planet from the Sun - is quite a beautiful and busy place.
MARTIAN WINTER WONDERLAND
The Red Planet has some truly amazing features. Rovers and landers send back images on a near daily basis, but the most exciting views often come from high above.
With six spacecraft currently orbiting the planet (three operated by NASA, two from the ESA and one from ISRO), there are a number of cameras snapping away, and recently, the European Space Agency's Mars Express orbiter captured this:
This is Korolev crater, an 82-kilometre-wide impact feature, located to the south of Mars' north polar ice cap. The image is a colour composite, produced by combining images taken by Express on five different passes over the area (the last of which was taken in April of 2018).
According to the ESA:
It is an especially well-preserved example of a martian crater and is filled not by snow but ice, with its centre hosting a mound of water ice some 1.8 kilometres thick all year round.
This ever-icy presence is due to an interesting phenomenon known as a ‘cold trap’, which occurs as the name suggests. The crater’s floor is deep, lying some two kilometres vertically beneath its rim.
The very deepest parts of Korolev crater, those containing ice, act as a natural cold trap: the air moving over the deposit of ice cools down and sinks, creating a layer of cold air that sits directly above the ice itself.
Behaving as a shield, this layer helps the ice remain stable and stops it from heating up and disappearing. Air is a poor conductor of heat, exacerbating this effect and keeping Korolev crater permanently icy.
For a much better perspective on this immense crater, the ESA mission team took the data from Express' passes to produce a three-dimensional digital terrain model, resulting in this oblique view of Korolev:
This pristine view of Korolov crater definitely brings to mind a winter wonderland (and appropriately so, since Mars' northern hemisphere is currently in winter), and it is an amazing example of what can be done with the spacecraft's imagery and data, capping off an incredible 15 years in orbit for Mars Express!
MARS INSIGHT SET (DOWN) FOR SCIENCE
NASA's newest Mars lander touched down on the Red Planet roughly a month ago, and has been engaging us all with the images it has been sending back (along with letting us here the winds of Mars)! Taking things slow and steady, the lander has now lifted its sensitive seismometer off of its deck, and has set it down on the Martian surface in front of it.
This animation is comprised of a string of raw images snapped by InSight, starting with an Instrument Deployment Camera (IDC) view of the SEIS instrument, then its Instrument Context Camera (ICC), showing how the lander picked up SEIS and set it down on the ground. Some of the images captured near dawn or dusk have been altered to increase their brightness, to better see what the lander is doing. Credit: NASA/JPL-Caltech/Scott Sutherland
How slow and how steady? The above sequence, of lifting the Seismic Experiment for Interior Structure (SEIS) off the lander and placing it on the surface, was imaged over a total of four (4) days, from December 19 to December 23, 2018 ('Sols' 22-26 of the InSight mission).
There was a very good reason for the slow pace of this deployment.
"Seismometer deployment is as important as landing InSight on Mars," Bruce Banerdt, InSight Principal Investigator at NASA's Jet Propulsion Laboratory, said in a press release. "The seismometer is the highest-priority instrument on InSight: We need it in order to complete about three-quarters of our science objectives."
By resting on the surface (and once it is covered over by the protective weather and thermal shield (WTS) dome), SEIS will record vibrations in Mars' surface, caused by wind, pressure changes, and 'marsquakes'. The data from this instrument will give the mission scientists a detailed look at what the interior of Mars is like.
Next, the team will ensure that the instrument is level, for best results, then cover it with the WTS dome, and begin bringing in this valuable science data!
SILENCE FROM OPPORTUNITY
The Mars Opportunity rover has now been silent for nearly 200 days!
This venerable explorer fell silent on June 10, 2018, in the midst of one of the worst global dust storms we have ever seen on Mars. As of mid-September, however, the skies over Opportunity have cleared enough for the rover's solar panels to collect power, yet we still have heard nothing from it.
According to JPL's latest update:
No signal from Opportunity has been heard since Sol 5111 (June 10, 2018). Opportunity likely experienced a low-power fault, a mission clock fault and an up-loss timer fault. Since the loss of signal, the team has been listening for the rover over a broad range of times, frequencies and polarizations using the Deep Space Network (DSN) Radio Science Receiver.
They have been commanding "sweep and beeps" throughout each daily DSN pass with both right-hand and left-hand circular polarization to address a possible complexity with certain conditions within mission clock fault on the rover. The team has expanded the breath of sweep and beep commanding covering more times of day on Mars.
What do these 'faults' mean?
• A low-power fault: Loss of power causes the rover to hibernate, and it should awaken when its solar panels gather enough power to top up its batteries.
• A mission clock fault: As its batteries ran down during the dust storm, the loss of power likely caused the rover's clock to hibernate. So, even if it wakes up when the skies clear, it doesn't know what time it is, so it doesn't know when it should be trying to communicate with home.
• An up-loss timer fault: the rover may think that its communication equipment is not functioning properly, due to the prolonged period of silence from Earth. The rover is programmed to attempt different ways of communicating, if it experiences this fault, however combined with the mission clock fault, it may not know when to make its attempts.
Combined, these three faults produce a variety of different scenarios for why Opportunity remains silent. It could still be receiving insufficient power from its solar arrays, due to a layer of dust that settled out of the storm. It may be receiving power from its arrays, but its attempts to communicate are always badly timed. There also could be other problems that have cropped up due to the lengthy dust storm and the long period of inactivity since.
The NASA team at JPL continues its attempts to contact Opportunity, however.
An animation of NASA's DSN Now website, on December 25, 2018.
As shown above, the Deep Space Network is still monitoring spacecraft operations throughout the solar system, even during the government shutdown. At the time this animation was captured, one of the Madrid antennas was listening to data from several Mars robots, including Mars Odyssey (M01O), Mars MAVEN (MVN), Mars Reconnaissance Orbiter (MRO), and Mars Opportunity (MER1)!
Does this mean that 'Oppy' is finally phoning home?
Well, it's possible! This is certainly the hope, as that would be an incredible Christmas present for the mission team. The likely truth, however, is that this is simply a scheduled time for the DSN to be listening to see if Opportunity calls. We'll have to wait until the team is back to work before we can know for certain.
Two hundred days is a long time for this rover to be out of contact with Earth, especially when it's been roughly three months since the skies had cleared enough to make contact possible.
Still, there is hope for Opportunity. According to the team, we are now in the right time for what are known as 'dust clearing events'. These are usually 'strong' gusts of wind (strong at least by Martian standards), or the passage of a dust devil, which clears off the rover's solar panels.
These two images from Opportunity's mastcam show a dust clearing event. The left image is from January 2014, while the right is from March 2014. Credit: NASA/JPL-Caltech/Cornell/ASU via The Planetary Society
So, keep Opportunity in your thoughts over the holidays, and maybe we'll hear from its soon!