planetology

The red colour of Mars corresponds to a type of ferrihydrite that is the dominant form of iron oxide in Martian dust, although previous studies have attributed it to anhydrous haematite. The persistence of ferrihydrite, whose formation requires water, suggests that it formed during a cold, wet period, followed by a transition to the planet's current arid environment. The result, based on ESA and NASA space data and new laboratory experiments, is published in Nature Communications.

US researchers have published a model showing that ice in the mid-latitudes of Mars could allow photosynthetic life to develop. Its thickness and composition would attenuate harmful ultraviolet radiation, but allow sufficient visible light to pass through. The work is published in the journal Communications Earth & Environment.

Fifteen years ago, the European Space Agency's (ESA) Mars Express probe revealed the presence of large deep deposits on Mars, in an area called the Medusae Fossae Formation (MFF), located at its equator. Now, new data from the probe's MARSIS radar indicate that the deposits are deeper than previously thought - up to 3.7 kilometers thick - and include both ice-rich and dusty layers. The results are published in Geophysical Research Letters.

A study published in the journal Nature Astronomy suggests the existence of an active mantle plume on Mars - a column of material from the mantle that generates hot spots - with a diameter of about 4,000 kilometres, which would explain its geological activity. The planet was traditionally considered to be geologically inert at present.

Based on a model, a study theorises that Mars may have been habitable for microorganisms 3.7 billion years ago, according to the journal Nature Astronomy.

Research published in Science proposes that an ancient moon of Saturn, which they have named Chrysalis (Chrysalis), may be responsible for Saturn's distinctive rings. According to the authors, the moon orbited around the gas giant for billions of years, but about 160 million years ago, it became unstable and moved too close to the planet, breaking apart under Saturn's tidal forces and forming the planet's rings. According to the research, Saturn's current tilt may also be related to the destruction of this moon.

After the scientific success and popularity of the Hubble and James Webb space megatelescopes, there are other smaller telescopes with important missions. This is the case of the European Space Agency's PLATO, whose telescopes will have the challenge of searching for exoplanets by monitoring hundreds of thousands of stars.

A study based on observations of the Greenland ice sheet, published in Nature Communications, suggests that there may be shallow liquid water on Jupiter's moon Europa. The finding could provide insights into the geophysical processes that formed the moon.