If the pace of discovery seems to be accelerating, that's surely because of the network of tools we're putting into place, able to work with each other both in space and on the ground to ferret out new information. Thus the collaborative effort that followed the remarkable observation of a new supernova, one caught so early in the process that it was found before visible light from the blast had begun to become apparent. We have such tools as the Swift satellite to thank for this. Its ongoing observations of a supernova in the spiral galaxy NGC 2770, ninety million light years from Earth in the constellation called the Lynx, caught a three-minute, 40 second x-ray burst from the same galaxy, another supernova in the process of happening. What Swift seems to have uncovered was the shock wave of kinetic energy heating gas in the star's outer layers to the temperatures that produce X-ray emissions. Such an event would be undetectable at optical wavelengths, which is where most supernovae...

By Larry Klaes An alternative title for Larry's new story might be "Toward a Science of Galactic Archaeology." For the vast cities of stars we see in the night sky are in a constant, if extremely long-term, process of re-shaping themselves through encounters with other galaxies, an activity whose traces in the distant past may still be detectable. In fact, astronomers hoping to learn more about such collisions may have a interesting remnant close at hand. As Larry writes, Omega Centauri offers some characteristics that set it apart from the average globular cluster, and point to a much different origin. Just days ago, the team that operates the Hubble Space Telescope (HST) released a large collection of images on the eighteenth anniversary of the astronomical instrument's deployment into Earth orbit that show dozens of galaxies doing what the team called "interactions" with each other, but which can just as easily be described as collisions. The new Hubble images show massive islands...

A tricky aspect of modern astronomy is keeping all the wavelengths straight. Take the case of G1.9+0.3, a supernova remnant (SNR) near the center of the Milky Way. If you look at an X-ray image of this object made with the Chandra satellite in 2007, you'll see clear signs of growth compared to what the Very Large Array saw in 1985. But the VLA was working at radio wavelengths, making the image comparison problematic. Scientists studying G1.9+0.3 therefore went back to the VLA to observe the object for a second time in order to verify their initial impression. The later study confirmed that this supernova remnant -- consisting of the materials ejected by the vast explosion -- really is growing at what seems to be an unprecedented pace. Fifteen percent growth in 23 years is no small matter in astronomical terms, and the growth also makes it possible to work backwards in time to arrive at the time the supernova went off, now pegged at 150 years ago. That makes G1.9+0.3 the youngest of...

With the GLAST mission near launch, keep in mind the possibilities of this unique observatory in terms of findings that could revolutionize our view of distant events. GLAST (Gamma-Ray Large Area Space Telescope) will be looking at things we've only recently learned about, such as the enigmatic gamma-ray bursts (GRBs) now flagged by the Swift satellite and quickly pinpointed for the use of Earth-based observatories. We know we're pushing into uncharted waters given that GLAST represents a major step forward over all previous satellites designed to study gamma ray events. And major new instruments usually deliver new classes of objects. Because of the increase in GLAST's sensitivity over earlier tools like the EGRET instrument on NASA's Compton Gamma-ray Observatory (CGRO), the satellite may find thousands of new point sources. And we have plenty of questions already on the table. Gamma-ray bursts, for example, may be the result of black hole mergers, or the merger of a black hole and...

It's hard enough to figure out what dark energy and dark matter are, a task that will occupy physicists for a long time to come. But even if we confine ourselves to 'normal' or 'baryonic' matter (accounting only for some four or five percent of the universe), we're still left with a problem. Baryons are heavy subatomic particles like protons and neutrons that experience the strong nuclear force, and the problem is that even these relatively familiar particles are only partially accounted for. So where is the missing baryonic matter? The answer may lie in a thin haze of hot, low-density gas that connects galactic clusters. Call it WHIM, for warm-hot intergalactic medium. Dutch and German scientists now think they have uncovered a filament of such gas that connects the clusters Abell 222 and Abell 223. The properties of the gas, visible primarily in the far ultraviolet and X-ray bands, fit with simulations in terms of density and temperature. The scientists used the XMM-Newton X-ray...