Astronomers searching for Earth-like planets have discovered one in another solar system that seems to have one of the unique criteria for sustaining life – a magnetic field.
You may not often pause to thank Earth’s magnetic field for you being here today, but it’s vital to protecting our planet’s life-sustaining atmosphere.
It does that by deflecting the high energy particles and plasma regularly blasted out of the sun.
Now scientists think they’ve found another Earth-sized planet with a magnetic field – YZ Ceti b, a rocky planet orbiting a star about 12 light-years away from Earth.
Because magnetic fields are invisible, it’s challenging to determine if a distant planet actually has one, according to Jackie Villadsen, an astronomer at Bucknell University in the US.
But being able to work out if they do is vital to the search for potentially habitable or life-bearing worlds, Joe Pesce from the National Science Foundation said.
“This research shows not only that this particular rocky exoplanet likely has a magnetic field but provides a promising method to find more,” he added.
The researchers detected radio waves which they theorised were generated by the interactions between the planet’s magnetic field and the star it orbits.
The research was published on Monday in the journal Nature Astronomy.
A planet’s magnetic field can prevent its atmosphere from being worn away over time by particles spewed from its star, Sebastian Pineda, an astrophysicist at the University of Colorado, said.
In other words, a strong magnetic field can mean life or death for a planet’s atmosphere.
YZ Ceti b is not habitable – it’s too close to its star for that, but it does have another similarity to Earth -the Northern Lights.
The sun’s high energy particles create solar weather around Earth, and the interaction between this and Earth’s magnetic field and atmosphere creates the phenomenon of the aurora borealis, or northern lights.
The interactions between YZ Ceti b and its star also create an aurora – but on the star itself.
However, the scientists said there should also be aurora on the planet if it has its own atmosphere.
Both researchers agreed YZ Ceti b is the best candidate yet for a rocky exoplanet with a magnetic field but said there will need to be “a lot of follow-up work” before it is confirmed.