Picture This

New views of dwarf planet Ceres as Dawn moves higher

19 November 2016 Astronomy Now

The brightest area on Ceres stands out amid shadowy, cratered terrain in a dramatic new view from NASA’s Dawn spacecraft, taken as it looked off to the side of the dwarf planet. Dawn snapped this image from about 920 miles (1,480 kilometres) above Ceres in its fifth science orbit, in which the angle of the Sun was different from that in previous orbits.

News

Did early Earth spin on its side?

1 November 2016 Astronomy Now

New theoretical modelling of the ancient history of the Earth and the Moon suggests that the giant collision that spawned our natural satellite may have left Earth spinning very fast, and with its spin axis highly tilted. The simulations give new insight into the question of whether planets with big moons are more likely to have moderate climates and life.

Observing

See asteroid 2 Pallas at its best during August 2016

15 August 2016 Ade Ashford

During the Perseid meteor shower, second-largest asteroid 2 Pallas passed close to the southeast of globular cluster Messier 15 in the constellation of Pegasus. The minor planet still lies in the vicinity of this beautiful deep-sky object, reaching opposition on 20 August — here’s our in-depth guide to Pallas at its best.

News

The case of the missing Ceres craters

27 July 2016 Astronomy Now

Ceres is covered in countless small, young craters, but none are larger than 175 miles (280 kilometres) in diameter. To scientists, this is a huge mystery, given that the dwarf planet must have been hit by numerous large asteroids during its 4.5 billion-year lifetime. Where did all the large craters go?

News

Mystery solved: Martian moons formed by a giant impact

5 July 2016 Astronomy Now

Where did the two natural satellites of Mars, Phobos and Deimos, come from? For a long time, their shape suggested that they were captured asteroids. However, the shape and course of their orbits contradict this hypothesis. Two independent and complementary studies now provide an answer: these satellites formed from the debris of a gigantic collision between Mars and a protoplanet one-third its size.

News

New details on Ceres seen in Dawn images

13 January 2016 Astronomy Now

Features on dwarf planet Ceres that piqued the interest of scientists throughout 2015 stand out in exquisite detail in the latest images from NASA’s Dawn spacecraft, which recently reached its lowest-ever altitude at Ceres. Dawn took these images near its current altitude of 240 miles (385 kilometers) between 19 and 23 December 2015.

News

Dawn gets the lowdown on dwarf planet Ceres

27 December 2015 Astronomy Now

NASA’s Dawn spacecraft, cruising in its lowest and final orbit at dwarf planet Ceres, has delivered the first images from its best-ever viewpoint. The new images showcase details of the cratered and fractured surface. Dawn is now approximately 240 miles (385 kilometres) above Ceres, which is where it will remain for the rest of its mission.

News

Stanford astronomers observe the birth of an alien planet

19 November 2015 Astronomy Now

Stanford University researchers announce evidence of an exoplanet being born that could move us one step closer to understanding the process of planet formation around other stars. The alien planet, called LkCa 15 b, orbits a star 450 light-years away and appears to be on its way to growing into a world similar to Jupiter.