For several decades, Mars has been a busy place, with orbiters, landers, and rovers providing unprecedented views of the Red Planet. Another exciting possibility which has yet to be realized is an airplane, which could soar through the atmosphere, showing Mars in a way not possible before – closer than an orbiter, but unique from a lander or rover stuck on the surface. NASA is now testing just such a concept, the first Mars airplane which could fly in the Martian skies in the 2020s.
The fact that Mars used to have large amounts of liquid water on its surface is pretty much accepted among scientists, but there is still the question of how long that water lasted. How long ago was it still present? A billion years? A few million? New evidence based on data from the Mars Reconnaissance Orbiter (MRO) suggests that water was still on the surface within the past million years, perhaps even as recently as 500,000 years ago, which is indeed recent, geologically speaking.
The puzzle of methane on Mars has taken an interesting new twist: for the first time, the gas has been detected within Martian meteorites. The finding adds another layer to the ongoing controversy over the origin of the methane, whether it is abiotic and geological or a potential biosignature of life, either past or present.
The debate over whether Mars used to be warmer and wetter or colder and wetter earlier in its history has been a long and contentious one. Now, a new study suggests it may be the latter, that Mars was indeed wetter, as overwhelming evidence has already shown, but that it was still a rather cold and icy climate overall.
The next NASA mission to Mars, the InSight lander, will include some additional experimental technology: the first deep-space CubeSats. Two small CubeSats will fly past the planet as the lander is descending through the atmosphere; this will be the first time CubeSats have been used in an interplanetary mission.