News

No large caverns found inside Comet 67P

Comets are known to be a mixture of dust and ice, and if fully compact, they would be heavier than water. However, measurements have shown some of them to have densities much lower than that of water ice, implying that comets must be highly porous. A new study of low-density Comet 67P/Churyumov-Gerasimenko using data from ESA’s Rosetta spacecraft rules out a cavernous interior.

News

James Webb Space Telescope primary mirror fully assembled

The final primary mirror segment is installed on NASA’s James Webb Space Telescope. Once in space and fully deployed, the 18 hexagonal-shaped mirror segments will work together as one large 6.5-metre mirror. The crowning mirror installation marks an important milestone in the assembly of what will be the biggest and most powerful space telescope ever launched.

News

Mystery within the deep-frozen ‘Flying Saucer’

Astronomers have made the first direct measurement of the temperature of large dust grains in the outer parts of a planet-forming disc around a young star. Observations of an object nicknamed the Flying Saucer reveals that the grains are much colder than expected. This surprising result suggests that models of these discs may need to be revised.

News

Saturn’s rings: less than meets the eye?

You might think that, in the rings of Saturn, more opaque areas contain a greater concentration of material than places where the rings seem more transparent. But this intuition does not always apply, according to a recent study of the rings using data from NASA’s Cassini mission. The research also suggests that the planet’s brightest B ring could be a few hundred million years old instead of a few billion.

News

Blast from black hole in distant Pictor A galaxy

By combining X-ray data from NASA’s Chandra X-ray Observatory over a 15-year period with radio data from the Australia Telescope Compact Array, astronomers have a better understanding of the active galaxy Pictor A, the supermassive black hole at its core and the enormous jet of particles it generates travelling at nearly the speed of light into intergalactic space.

News

Pluto’s blue atmospheric ring in the infrared

A new image from NASA’s New Horizons spacecraft is the first look at Pluto’s atmosphere in infrared wavelengths, and the first image of the atmosphere made with data from the probe’s LEISA instrument. The blue ring around Pluto is caused by sunlight scattered from a haze of hydrocarbon particles in the form of a photochemical smog.

Equipment

Gerd Neumann Ronchi eyepiece

We can become very attached (even fondly) to the instruments that give us such a thrill observing the Universe. It can come very hard, then, for us to question their quality. Reviewer Steve Ringwood takes a look through a Ronchi eyepiece that permits the user to obtain a definitive and exacting exposure of a telescope’s optical quality.

Picture This

The unearthly beauty of the Red Rectangle

Straight lines do not often crop up in space. Whenever they do, they seem somehow incongruous and draw our attention. The Red Rectangle, a so-called planetary nebula surrounding the double star HD 44179 some 2300 light-years away in the constellation of Monoceros, is one such mystery object.