NuSTAR continues to do well - our first official image release came out. It shows the giant flare from the Galactic center black hole, Sgr A*. NuSTAR got lucky and caught it on the first night we looked at the GC. Just last week we got lucky again, and saw another big one - this time at the same time the Chandra observatory was looking. What will be interesting is to look at the distribution of X-ray energies, especially above energies of 10keV, where no telescope has been senstive enough to isolate the emission from Sgr A* itself.
NuSTAR continues to do well. Right now we're pointing at a neutron star called Hercules X-1. Neutron stars have masses somewhat larger than our Sun, but are as compact as San Francisco. A teaspoon weighs as much as all the humans on Earth. These objects also have very intense magnetic fields. When they are in a binary system with a "normal" star matter can be transferred from the star to the neutron star. The huge magnetic fields create distortions in the spectrum (or rainbow) of X-rays that result, and NuSTAR will study this distorted spectrum to understand the physics taking place in these systems.
In other news - want to catch up in person? We're hosting a google+ event to roll out the KQED (Bay Area public television) show on black holes, highlighting NuSTAR.
Add KQED Science to your circle and you'll find the event.
NuSTAR is finally really in science mode - we're planning the observations for the whole month of September. Its an exciting month. We'll be looking at a nearby "starburst galaxy" - or a galaxy that is forming stars at an amazing rate - much greater than our Milky Way. The rate of star formation is so great for a galaxy undergoing a starburst that, if the rate was sustained, the gas reservoirs from which stars are formed would be used up on timescales much shorter than the age of the galaxy. So, these special galaxies must have something in their recent past that triggers this amazing rate of star formation. A consequence of forming a lot of stars is that you end up with a lot of black holes and neutron stars, which are the endpoints of massive star formation. These objects shine in the X-ray band, and in particular extending sensitivity to the high energy X-ray band can tell us about the composition of the population of compact objects (black holes vs. neutron stars) which is interesting for understanding the ratio of high to low mass star formation.
NuSTAR continues to look at the Cassiopeia A supernova remnant through tonight. Then, we slew to pick up a simultaneous observation with Chandra of an ultraluminous infrared galaxy, to help answer the question of whether a central black hole or star formation power these galaxies. Then, back to a new position on Cas A. We plan to post an image of the supernova remnant taken with NuSTAR soon.
Right now NuSTAR is looking at a famous remnant of a supernova explosion in the constellaton Cassiopeia. The remnant, called "Cas A" is the brightest extrasolar radio source in the sky. The supernova occurred approximately 11,000 light-years (3.4 kpc) away in the Milky Way.The expanding cloud of material left over from the supernova is now approximately 10 light-years (3 pc) across. Despite its radio brilliance, however, it is extremely faint optically, and is only visible on long-exposure photographs.
NuSTAR's high energy X-ray image will trace the distribution of radioactive elements in this remnant, telling us about the explosive dynamics in the core of the supernova.
The NuSTAR team is working hard to interpret the data taken during calibration of the observatory so that the data from this science observation can be used to understand the absolute brilliance of this object in the high energy X-ray region of the spectrum.