We can use galaxy clusters for many different science goals, but first we need to figure out where they are.

Miszalski et al. show that the well-known planetary nebula Abell 70 has a white dwarf companion at its center with a messy past.

I just vacuumed my apartment and asked the question, 'how does so much dust accumulate in one week?' These authors ask a more scientifically interesting question: how can galaxies accumulate more than 100 million solar masses of dust in just a few hundred million years?

What will happen if Cygnus X-1 evolves to become a system of two massive, compact objects (and will we ever find out)?

What do grad students do all day? Read on for more than a dozen personal reports from the field.

A 2011 article for GradHacker about being an astronomy graduate student.

SN 2009nz may be the sixth GRB-supernova ever confirmed spectroscopically.

Star formation at the center of galaxies can be triggered by both internal and external processes. In their new work, Ellison et al. argue that the internal processes may be more important.

These authors use the surface of the Moon to distinguish between binary star systems separated by just thousandths of an arcsecond - far smaller than can be resolved by traditional imaging.

A 2011 article for Physics Today about public engagement for science.

The BOSS project of the Sloan Digital Sky Survey is exploiting the Lyman-α forest in distant quasars to make a 3D map of neutral hydrogen in the early universe.

The SMC is one of the best studied galaxies in the sky, but there is still plenty to learn from the stars far from its center.

Bulges are a familar feature of spiral galaxies, but bulges seem to come in many shapes and sizes. Studying bulges can provide clues for the role of galaxy mergers in the history of the universe.

If you see a bunch of galaxies together in a cluster, are their orientations and orbits random or do they align?

The SAO ds9 image viewer is one of the most widely used tools in astronomy. Read more to learn the basics of ds9 and check out some of the advanced features.

Compositional investigations of comets have suggested that they are "icy dirtballs," so would it be possible to detect traces of hydrogen and oxygen if they were flung from one stellar system into the atmosphere of another star?

Each galaxy in the sky will probably produce just one or two supernovae in our lifetimes, so you have to be lucky to spot one. But if you happen to be observing hundreds of thousands of galaxies anyway, you're bound to catch a few.

This morning I was delighted to receive an email from Avi Loeb, who's paper on the (far) future of astronomy [we discussed yesterday](https://astroph.

Update: you can read Avi Loeb and Freeman Dyson's discussion of this issue in [our latest post](https://astroph.wordpress.com/2011/02/03/avi-loeb-and-

Supernovae are vitally important in the chemical and dynamical evolution of galaxies, but we don't yet fully understand the physics that produce these explosions. This new work simulates the turbulent instabilities in a star at the brink of core-collapse.