SoylentNews is people
SoylentNews
Astronomers have measured gases in the atmosphere of a "super-Earth" exoplanet, 55 Cancri e:
For the first time, astronomers have managed a direct measurement of the gases present on a "super-Earth" planet orbiting an alien star. They found evidence for hydrogen and helium in its atmosphere, but no water. Called 55 Cancri e, the world is twice the size of Earth and eight times the mass - but orbits unusually close to its host star, with an 18-hour year and surface temperatures above 2,000C. The UK team published their findings in the Astrophysical Journal.
"This is a very exciting result because it's the first time that we have been able to find the spectral fingerprints that show the gases present in the atmosphere of a super-Earth," said Angelos Tsiaras, a PhD student at University College London and the first author of the paper. "Our analysis of 55 Cancri e's atmosphere suggests that the planet has managed to cling on to a significant amount of hydrogen and helium from the nebula from which it formed."
55 Cancri e is at least 48% as massive as Neptune. The exoplanet is about 40 light years away from Earth.
Detection of an atmosphere around the super-Earth 55 Cancri e
(Score: 2) by GreatAuntAnesthesia on Thursday February 18 2016, @12:01PM
Could be way off base here, but surely if most of the material making up the planet is at or above its melting point, then you could expect the whole stew to separate itself quite neatly into layers. If the planet is tidally locked and without any moons then there might not be too much gravitational / tidal stirring to prevent this. All the silica would settle below the iron, and the lighter elements would settle above them, band by band. Anything with a high enough melting point to remain solid would just sink down to the core. This means that any measurements we make from here would only see the uppermost layers, made up of the lightest elements.
(Score: 2) by stormwyrm on Friday February 19 2016, @12:57AM
Numquam ponenda est pluralitas sine necessitate.
(Score: 2) by GreatAuntAnesthesia on Friday February 19 2016, @09:43AM
Well that's what I was thinking. The tidal stresses would be enormous, but (assuming a not-too-elliptical orbit and no other bodies nearby exerting significant gravitational influence) they would be constant. Surely that would result in a state of equilibrium, rather than a state of chaos..? The forces on an astronaut accelerating at 1g are pretty impressive, but it's only when he suddenly stops / accelerates more that things start falling off the shelves.