BBC Sky at Night Magazine
Eye on the sky
Cosmic clouds of glowing gas may hold the secrets to star formation
HUBBLE SPACE TELESCOPE, 18 MARCH 2020 Its rather dull name, LHA 120-N 150, belies the beauty of this bright pink crucible of star formation sitting on the edge of the Tarantula Nebula. A super-concentrated area of massive stars, called a super star cluster, it lies relatively near to us at 160,000 lightyears away in the Large Magellanic Cloud. With little obscuring cosmic dust in between, the region is readily viewable from Earth and so is now a favourite target for astronomers hoping to understand how stars, particularly massive stars, are born. One theory is that they form within and are then ejected from clusters in the glowing clouds of gas and dust. Already, though, this would appear to be contradicted by observations that many of the stars studied seem to form in isolation. What makes the task even harder is that although the region potentially hosts dozens of ‘stars’ to study, young massive stars can appear similar to dense clumps of dust.
HUBBLE SPACE TELESCOPE, 23 MARCH 2020
Instead of the conventional two or more arms, unusual barred spiral galaxy NGC 4618 has just one curling out from its centre. Found 21 million lightyears away in Canes Venatici, its asymmetry may come from a long-past gravitational tussle with nearby neighbour NGC 4625. If so, it’s hard to know which came off worst, as both combatants lost an arm in the galactic face-off. Lop-sided, single-armed galaxies like this are sometimes called Magellanic spirals because of their resemblance to the Magellanic Clouds.
Face of a killer?
OSIRIS-REX SPACECRAFT, 19 MARCH 2020
This mosaic, compiled by NASA from 2,155 images taken by the OSIRIS-REx spacecraft last spring, reveals the surface of the asteroid Bennu as never seen before. OSIRIS-REx passed just 3–5km above the asteroid’s surface to capture these detailed pictures. Bennu, dubbed a Doomsday asteroid by some, is on both NASA’s and ESA’s risk lists, with a 1-in-2,700 chance of striking Earth in the late 22nd century.
What Apollo 13 saw
LUNAR RECONNAISSANCE ORBITER, 24 FEBRUARY 2020
It was a cruel twist that, their mission aborted, the only way Apollo 13’s crew could steer for home was to ‘slingshot’ their stricken craft around the far side of the Moon, passing tantalisingly close to the lunar surface on which they would never land. Lovell, Swigert and Haise could only look down and take photos in those 25 minutes of radio silence as they passed from light, to dark, to light again. Their view in those moments of isolation has now been digitally recreated in crisp 4K from detailed images taken by the robotic Lunar Reconnaissance Orbiter. View the full film here: nasa.gov/multimedia/videogallery/index.html
Peace on Earth?
INTERNATIONAL SPACE STATION, 20 MARCH 2020
The lights of Europe and Asia glint prettily beneath a star-packed sky in this image taken from the International Space Station in March. The three crew members on board, safely isolated from COVID-19, orbit 400km above Earth, their home a football pitch-sized craft travelling at 28,000km/h. As work at space agencies around the globe is put on pause in the face of the pandemic, the station’s international crew continue their schedule of maintenance tasks and experiments. They still see 16 sunrises and sunsets every day: the world keeps turning.