At noon Eastern time on Wednesday, the NuSTAR (Nuclear Spectroscopic Telescope Array) blasted towards low-Earth orbit from a Pegasus XL rocket, after it was dropped from the belly of a carrier jet circling near the Kwajalein Atoll in the Pacific Ocean.

The X-ray mission, a low-cost NASA mission in its small Explorer line of competitive missions, is expected to discover hundreds of supermassive black holes in the hearts of distant galaxies.

A lot is riding on the NuSTAR — it is one of few missions in sight for X-ray astronomers. Just last week, GEMS (the Gravity and Extreme Magnetism Small Explorer), a similar-looking mission that would have gathered polarized X-ray light, was cancelled because of budget over-runs. Although NuSTAR is no replacement for general purpose X-ray observatories such as Chandra and XMM-Newton, it will have unprecedented sensitivity in the ‘hard’, or high-energy, X-ray part of the spectrum.

Fifteen minutes after launch, the science payload had separated from the rocket. By 12:22 p.m. Eastern time all five of NuSTAR’s solar panels had been deployed successfully. But it will be another week before the most nerve-wracking phase of the mission begins — the 26 minutes during which a deployable mast will unfurl itself so that NuSTAR can reach its full 10-metre focal length.

Image: NASA via UStream