Category Astronomy/Space

The High-Altitude Water Cherenkov Gamma-Ray Observatory (HAWC) is a detector designed to look at gamma-ray emission coming from astronomical objects such as supernova remnants, quasars and rotating dense stars called pulsars. Located roughly 13,500 feet above sea level near the Sierra Negra volcano in Mexico, the detector is composed of more than 300 tanks of water, each about 24 feet in diameter. When particles strike the water, they produce a shock wave of blue light called Cherenkov radiation. Special cameras in the tanks detect this light, allowing scientists to determine the origin of incoming gamma rays.
Credit: Jordan Goodman/University of Maryland

Space jets accelerate particles and send a high-energy signal to Earth...

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...