It is now widely accepted that Mars was once a very wet place. About four
billion years ago Mars would have had enough water to
cover its entire surface in a liquid layer about 140 metres deep. It is likely that the liquid would have pooled to form an ocean
occupying almost half of Mars’s northern hemisphere, and in some regions
reaching depths greater than 1.6 kilometres. This artist’s impression shows what the planet may have looked like with its ancient ocean. Imagine: could life have lived in such a place?
“This broad image of the Carina Nebula, a region of massive star
formation in the southern skies, was taken in infrared light using the
HAWK-I camera on ESO’s Very Large Telescope. Many previously hidden
features, scattered across a spectacular celestial landscape of gas,
dust and young stars, have emerged.”
This image was captured in the infrared by ESO’S HAWK-I, an infrared instrument on the Very Large Telescope array in Chile. This new image reveals 10 times as many brown dwarfs and isolated planetary objects as was previously known.
This spidery nebula, known as the Tarantula Nebula, is seen in the top center of this cosmic image. If you look to the lower right of the Great Nebula, a web of filaments contain the famous supernova SN
1987A - with its remnants now illuminating these regions. Many other reddish nebulae are visible in the image, as well as a
cluster of young stars on the left, known as NGC 2100.
Here, within the stellar nursery IC 2944, we see a group of thick clouds of dust known
as the Thackeray globules (a more specific Bok Globule) silhouetted against the pale pink glowing gas
of the nebula. These globules are under fierce bombardment from the
ultraviolet radiation from nearby hot young stars within the surrounding emission-type nebula. They are both being
eroded away and also fragmenting, rather like lumps of butter dropped
onto a hot frying pan. Due to this process, it is likely that Thackeray’s globules will be
destroyed before they can collapse and form new stars.