Beautiful and Unexplained Mars Aurora

(Image: University of Colorado)

Mars is quite a wonderful little planet. Obviously, it’s one of the best potential places to find extra-terrestrial organisms (or, at least, fossilized specimens) within the Solar System. Early on in it’s life it would’ve been quite similar to Earth with water flowing on the planet. And now we’re seeing an aurora on it that we can’t quite explain yet (we’ve seen Martian auroras before, but we COULD explain those ones through the same process we can explain Earth’s auroras, namely highly charged particles from the sun interacting with Earth’s magnetic field). As Jacob Aron from the New Scientist explains:

The new aurora, dubbed “Christmas lights” by the team because it occurred from 18 to 23 December last year, is different. It was seen in many different parts of the northern hemisphere and at much lower altitudes than previous auroras. “We’re seeing it not connected to magnetic regions,” says Jakosky. “We don’t know if it is occurring only at the places we’re observing, or if it is globally distributed.”

The timing lined up with a spike in electrons streaming in from the sun at high enough energies to penetrate down into the atmosphere, suggesting this had a hand in creating the aurora, but exactly how it occurs is unknown. The MAVEN team is now planning to look at the entire hemisphere when the spacecraft is in the shadow of Mars, facing the sun, but it is a risky move as MAVEN is not designed to look straight at the sun. “We have to be really careful because we have to turn off some protective measures,” says Jakosky. “If we screw it up we’re going to burn out the instrument.”

They also detected a cloud of dust, which was at least 200km’s above the surface, that stayed for the duration the spacecraft had been operating. Perhaps it’s dust that falls from one of Mars’ moons (Phobos and Deimos), or perhaps it’s coming from the random bits and bobs that float through the Solar System (like comets or asteroids) or it could even be coming from the planet itself (although we don’t know of a mechanism that would bring dust from the surface to such heights). But they don’t know, more research and observation are needed.

The beauty of the solar system is wonderful. I can’t wait to find out more.

Gamma Ray Bursts, Mass Extinctions and the Fermi Paradox

Interestingly, in a study published on arXiv.org, we find the potential that gamma ray bursts (massive explosions with the majority of the energy directed out of the magnetic poles that occur when stars go hypernova or two neutron stars collide or even coming from black holes) could explain away the Fermi Paradox (the question that given the ubiquity of planets, the age of the universe and some other factors, why haven’t we been visited by aliens yet).

When the universe was younger (the article states from the beginning of the universe to about 5 billion years ago) the galaxies were smaller and much more tightly packed with stars, which meant the chances of a planet being hit by a gamma ray burst was really quite high (95% chance within a billion years). The gamma ray bursts would sterilise the planets, meaning that no life could have evolved before 5 billion years ago. Continue reading