Starship Asterisk*

They may only be little, but they pack a star-forming punch: new observations from the NASA/ESA Hubble Space Telescope show that starbursts in dwarf galaxies played a bigger role than expected in the early history of the Universe.

• Astrophysical Journal 789(2) 96 (10 Jul 2014) DOI: 10.1088/0004-637X/789/2/96
  arXiv.org > astro-ph > arXiv:1406.4132 > 16 Jun 2014

Astronomers have discovered strange and unexpected behaviour around the supermassive black hole at the heart of the galaxy NGC 5548. The international team of researchers detected a clumpy gas stream flowing quickly outwards and blocking 90 percent of the X-rays emitted by the black hole. This activity could provide insights into how supermassive black holes interact with their host galaxies.

• Science (online 19 Jun 2014) DOI: 10.1126/science.1253787

This bright spiral galaxy is known as NGC 2441, located in the northern constellation of Camelopardalis (The Giraffe). However, NGC 2441 is not the only subject of this new Hubble image; the galaxy contains an intriguing supernova named SN1995E, visible as a small dot at the approximate centre of this image.

The Sun sets over Paranal Observatory, painting an array of subtle hues across the sky reminiscent of a Monet landscape. The sparse clouds glow warmly under the Sun's last rays, and the crisp clarity of the air is almost palpable — highlighting why ESO has selected this area of Chile for its observatory. Crepuscular rays — and shadows from the clouds — are streaming from the Sun and appear to converge at the antisolar point. ...

Discovered by astronomer William Herschel in the late 1700s, NGC 201 is a barred spiral galaxy similar to our own galaxy, the Milky Way. It lies 200 million light-years from Earth in the constellation of Cetus (The Sea Monster), and is invisible to the naked eye.

This new NASA/ESA Hubble Space Telescope image of NGC 201 shows the galaxy in striking detail, capturing the bright centre and the barred spiral arms — arms that do not start directly from the galactic centre, but instead seem to be offset and stem from a "bar" of stars cutting through the middle of the galaxy.

Along with three of its closest galactic neighbours (outside the frame), NGC 201 belongs to a group known as the HCG 7 compact galactic group. Hickson Compact Groups (HCG) are relatively small and isolated systems containing a handful of bright, compact galaxies that lie close to one another. As the galaxies within these groups move closer together they interact strongly, dragging galactic material out into space and distorting the structure of the other group members.

Eventually, all the galaxies within one HCG will merge together. Simulations have shown that within a billion years, the galaxies within one HCG have merged to form a giant fossil galaxy. It is possible that this is the final fate of all galactic groups.

The little-known cloud of cosmic gas and dust called Gum 15 is the birthplace and home of hot young stars. Beautiful and deadly, these stars mould the appearance of their mother nebula and, as they progress into adulthood, will eventually also be the death of her. ...