Category Astronomy/Space

During Cassini’s ‘Grand Finale’ plunge into Saturn’s innermost ring and upper atmosphere in 2017, the mass spectrometer aboard the probe sampled chemicals at altitudes between Saturn’s rings and atmosphere.
Credit: NASA

A new study based on data from the final orbits last year of NASA’s Cassini spacecraft shows the rings of Saturn – some of the most visually stupendous objects in the universe – are far more chemically complicated than previously was understood. Political humorist Mark Russell once joked, “The scientific theory I like best is that the rings of Saturn are composed entirely of lost airline luggage.”

Well, there’s no luggage, it turns out...

Artist’s conception of a Gamma Ray Burst. Jets of fast-moving material are propelled outward through a spherical shell of ejected material from the initial explosion of a massive star and its collapse into a black hole.
Credit: Bill Saxton, NRAO/AUI/NSF

A team of astronomers has detected the sonic boom from an immensely powerful cosmic explosion, even though the explosion itself was totally unseen. For years, astronomers have been hunting all over the sky for an example of this strange phenomenon, known as an “orphan afterglow.” At last, now they’ve finally found one.

The titanic eruption, known as a Gamma Ray Burst (GRB), was generated by the collapse of a massive star in a galaxy nearly 300 million light-years from Earth...

This is an artist’s impression of the exoplanet Kepler-1625b, transiting the star, with the candidate exomoon in tow.
Credit: Dan Durda

New Neptune-sized exomoon candidate has been observed around a star some 8,000 light years away. A pair of Columbia University astronomers using NASA’s Hubble Space Telescope and Kepler Space Telescope have assembled compelling evidence for the existence of a moon orbiting a gas-giant planet 8,000 light-years away.

In a paper published Oct. 3 in the journal Science Advances, Alex Teachey and David Kipping report that the detection of a candidate exomoon – that is, moons orbiting planets in other star systems – is unusual because of its large size, comparable to the diameter of Neptune...

A universe aglow.
Credit: ESA/Hubble & NASA, ESO/ Lutz Wisotzki et al.

MUSE spectrograph reveals uncovered vast cosmic reservoirs of atomic hydrogen. An unexpected abundance of Lyman-alpha emission in the Hubble Ultra Deep Field (HUDF) region was discovered by an international team of astronomers using the MUSE instrument on ESO’s Very Large Telescope (VLT). The discovered emission covers nearly the entire field of view – leading the team to extrapolate that almost all of the sky is invisibly glowing with Lyman-alpha emission from the early Universe.

Astronomers have long been accustomed to the sky looking wildly different at different wavelengths, but the extent of the observed Lyman-alpha emission was still surprising...