Psychedelic Pluto

NASA has selected three finalists for a new Explorer-class astrophysics satellite mission scheduled to launch by the end of 2020, and two of the proposals aim to fulfill similar goals to an X-ray telescope shelved after cost overruns in 2012.

For the first time, an international team of scientists from NASA, the Institute of Planetology and Astrophysics of Grenoble (IPAG), the European Space Agency and Aalto University in Finland, have predicted that colourful, glowing aurorae can be seen by the naked eye on a terrestrial planet other than Earth — Mars.

We can’t see the wind, but we can learn about it by observing things that are being blown about. And by studying changes in a comet’s bright tail of gas and ions, scientists are on the trail to solving two big mysteries about the solar wind — the supersonic outflow of electrically charged gas from the Sun’s million-degree upper atmosphere, or corona.