
Copernical Team
The obliquity of Mars: Periodic bedding in Tithonium Chasma

Earth's seasons are caused by the tilt of our planet's rotational axis to the orbital plane or obliquity. Mars' obliquity is currently about 25 degrees, which is not much different from Earth's 23 degrees. However, numerical calculations by scientists at the Paris Observatory and Massachusetts Institute of Technology suggest that this near-agreement is a coincidence.
Under the influence of gravitational torques from other planets, Mars' obliquity varies chaotically, probably reaching values greater than 60 degrees and lower than 10 degrees. By contrast, Earth's obliquity appears to have been limited to small variations from its current value because of the stabilizing gravitational influence of the Moon. If the calculations are correct, then for most of the Solar System's history, the obliquity of Mars was greater than 25 degrees. This would produce warmer summers and colder winters than on present-day Mars. On Earth, a recent 1 degree rise in obliquity is believed to have triggered ice sheet retreat from the current location of New York City to Greenland. The climatic consequences of 50 degree changes in obliquity on Mars remain unknown.
It is possible, though unproven, that higher obliquity triggered partial melting of some of Mars' water ice.
Image: Frosty scenes in Martian summer

The CaSSIS camera onboard the ExoMars Trace Gas Orbiter captured remnant frost deposits in a region near Sisyphi Tholus, in the high southern latitudes of Mars (74ºS/246ºE).
This image was taken during the early morning of a midsummer day in the southern hemisphere. At these high latitudes, carbon dioxide ice and frost develop. Frost can be seen within polygonal cracks in the terrain, a feature that indicates the presence of water ice embedded in the soil. The black spots observed throughout the scene are due to dark soil being pushed through cracks in the carbon dioxide ice as it sublimates—turns directly from solid ice to vapor—in the summer months.
The scale is indicated on the image.
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Energy from solar wind favors the north

Using information from ESA's Swarm satellite constellation, scientists have made a discovery about how energy generated by electrically-charged particles in the solar wind flows into Earth's atmosphere—surprisingly, more of it heads towards the magnetic north pole than towards the magnetic south pole.
The sun bathes our planet with the light and heat to sustain life, but it also bombards us with dangerous charged particles in the solar wind.
Ariane 6 launch complex – December 2020

Pool preps

Prepping for a spacewalk typically means diving underwater to rehearse and fine-tune operations.
In 2016, ESA astronaut Alexander Gerst performed such an underwater rehearsal for the Colka high speed radio, the brown box imaged above, that will be installed this month on the International Space Station.
NASA astronauts Mike Hopkins and Victor Glover will integrate the small fridge-sized device outside the European Columbus module during a spacewalk scheduled this year. ESA astronaut Andreas Mogensen will be at NASA’s mission control directing the spacewalkers as Capcom. The Columbus Ka-band terminal, nicknamed ‘Colka’, will enable faster communication with Europe.
Orbiting the planet every
Madrid snowbound

Energy from solar wind favours the north

Using information from ESA’s Swarm satellite constellation, scientists have made a discovery about how energy generated by electrically-charged particles in the solar wind flows into Earth’s atmosphere – surprisingly, more of it heads towards the magnetic north pole than towards the magnetic south pole.
New Space Telescope Will Reveal Unseen, Dynamic Lives of Galaxies

Arecibo observatory helps find possible 'first hints' of low-frequency gravitational waves

Astronomers measure enormous planet lurking far from its star
