A group of astronomers has been able to follow stardust being made in real time — during the aftermath of a supernova explosion.
For the first time they show that these cosmic dust factories make their grains in a two-stage process, starting soon after the explosion, but continuing for years afterwards.
The team used ESO’s Very Large Telescope (VLT) in northern Chile to analyse the light from the supernova SN2010jl as it slowly faded. The new results are published online in the journal Nature on 9 July 2014.
Pismis 24-1 shines brightest at the top center of this image, which displays the NGC 6357 nebula in Scorpius. Researchers previously considered Pismis 24-1 the most massive star in the galaxy at 200-300 solar masses, far above the current theorized limit of 150 solar masses. However, Hubble and ground-based telescopes have discovered that Pismis 24-1 is not merely a binary star system, but it is composed of a tight binary star system and a third star, meaning the individual stars cannot have broken the mass record.
The Cassini spacecraft looks down on the north pole of Saturn. The scene is serene only from a distance—raging storms are clearly visible in the atmosphere. In this image you can even make out Saturn’s hexagonal storm. The hexagonal vortex is about 20,000 miles (30,000 km) across and is a jet stream made up of 200 mph winds (322 km/h) surrounding a huge storm, Scientists have not found another weather feature exactly like this anywhere in the solar system.
(Credit: NASA / JPL / SSI / processed by Bill Dunford)
Hubble traces the halo of a galaxy more accurately than ever before
Observations reveal that Centaurus A’s halo spreads far further into space than expected.
There is more to a galaxy than first meets the eye. Extending far beyond the bright glow of a galaxy’s center, the swirling spiral arms, or the elliptical fuzz is an extra component — a dim halo of stars sprawling into space.
These expansive halos are important components of a galaxy. The halo of our galaxy, the Milky Way, preserves signatures of both its formation and evolution. Yet we know very little about the halos of galaxies beyond our own because their faint and spread-out nature makes exploring them more difficult. Astronomers have so far managed to detect very few starry halos around other galaxies.