As one NASA marks the end of one of the missions on Mars, another is preparing for a future mission.
NASA's InSight mission has been on Mars for nearly four years.
Over time, dust has built up on the solar arrays, slowly been caked on. Missions that go to Mars are equipped with little blowers that use pressurised air to blow some of the dust off.
However, over time, too much dust builds up and it won't come off. As it does, the charge of the batteries reduces, much like one in an old phone or computer, and they do not get fully charged.
At some point, they finally get too low on power, and turn off.
A similar fate happened to the rover Opportunity after about 12 years of operation on Mars.
A massive global dust storm kicked up - it was so noticeable telescopes on Earth were able to see it.
The vast amount of dust deposited on the solar arrays, and enough could not be cleaned off until it too ran out of power.
A few days ago, InSight sent this likely final, and somewhat sad, message to Earth:
"My power's really low, so this may be the last image I can send. Don't worry about me though: my time here has been both productive and serene. If I can keep talking to my mission team, I will - but I'll be signing off here soon. Thanks for staying with me."
InSight has been studying what is happening underneath Mars - such as its layers - the crust. mantle, and core. It found the crust is a bit thinner than expected, while its core is molten, like Earth, but larger than expected.
It also measured a lot of Marsquakes - the Martian equivalent of earthquakes It detected hundreds of them form a variety of sources - such as meteors hitting Mars and activity underneath like on Earth.
Some of the Marsquakes were more violent and lasted a long time - one lasted nearly 100 minutes.
It has been an amazing mission that has given us lots of data on what is happening underneath our red neighbour.
As InSight ended its mission though, this week, NASA's latest rover, Perseverance, which landed on Mars in February of last year, stored its first sample for an eventual return to Earth.
It has been gathering samples underneath, drilling down and extracting rocks and other samples. It is exploring an area we think may have had a lot of water, and therefore likely to have signs of life.
In a 15 centimetre titanium tube, that looks more like a lightsaber or sonic screwdriver from Doctor Who, sample of rocks are stored and left on the surface.
The plan is that later this decade, two drones will go to Mars, collect the sample along with nine others, and bring them back to a launch vehicle, which will then return to Earth towards the end of the decade. It is the ultimately game of drone fetch.
The science on Mars never stops, and it is never dull. Farewell InSight.
- Brad Tucker is an astrophysicist and cosmologist at Mount Stromlo Observatory and the National Centre for the Public Awareness of Science at the ANU.
