When galaxies collide, stars seldom crash into each other because they are still separated by enormous distances. But as this Hubble Space Telescope view of NGC 3256 shows, gas and dust in colliding galaxies can come together with spectacular consequences, triggering the formation of vast numbers of new stars and clusters. NGC 3256, located about 100 million light-years from Earth in the constellation of Vela, is the result of the collision of two Milky Way-size galaxies that began about 500 million years ago. It is now an especially luminous starburst galaxy oriented face-on to Earth and showing two distinct nuclei, one of them shrouded by gas and dust, surrounded by more than 1,000 bright star clusters embedded in crisscrossing dust lanes and a large disk of molecular gas. The two galaxies merging in NGC 3256 had similar masses and in a few hundred million years, astronomers say, the two cores will complete the merger to produce a single large elliptical galaxy.
Astronomers harnessing the combined power of NASA’s Hubble and Spitzer space telescopes have found the faintest object ever seen in the early universe. It existed about 400 million years after the big bang, 13.8 billion years ago. The new object is comparable in size to the Large Magellanic Cloud (LMC), a diminutive satellite galaxy of our Milky Way.
This glorious spiral galaxy is known as NGC 24, measures some 40,000 light-years across and lies about 25 million light-years away in the southern constellation of Sculptor. However, there may be more to this picture than first meets the eye: 80 percent of NGC 24’s mass is thought to be held within an invisible dark matter halo.
A new analysis of 13 supernovae — including archived data from NASA’s Hubble Space Telescope — is helping astronomers explain how some young stars exploded sooner than expected, hurling them to a lonely place far from their host galaxies. It’s a complicated mystery of double-star systems, merging galaxies, and twin black holes.