Scientists were able to observe the demise of a star and its digestion by a previously dormant supermassive black hole in real time. f a star passes too close to a black hole, tidal forces can rip it apart, and its constituent gases then swirl in toward the black hole. Friction heats the gases and causes them to glow. By searching for newly glowing supermassive black holes, astronomers can spot them in the midst of a feast. Harvard Professor Edo Berger is a co-author on this study. 

Read more at Astronomy Magazine or read the CFA press release. 

Credit: NASA/S. Gezari (JHU)/A. Rest (STScI)/R. Chornock (Harvard-Smithsonian CfA)

The Tycho supernova remnant is the result of a Type Ia supernova explosion. The explosion was observed by Danish astronomer Tycho Brahe in 1572. More than 400 years later, the ejecta from that explosion has expanded to fill a bubble 55 light-years across. In this image, low-energy X-rays (red) show expanding debris from the supernova explosion and high energy X-rays (blue) show the blast wave - a shell of extremely energetic electrons. Credit: X-ray: NASA/CXC/Rutgers/K.Eriksen et al.; Optical: DSS

CFA Clay Fellow R. Foley and Harvard Astronomy Professor R. Kirshner publish new findings. The exploding stars known as Type Ia supernovae serve an important role in measuring the universe, and were used to discover the existence of dark energy. They're bright enough to see across large distances, and similar enough to act as a "standard candle" - an object of known luminosity. The 2011 Nobel Prize in Physics was awarded for the discovery of the accelerating universe using Type Ia supernovae. However, an embarrassing fact is that astronomers still don't know what star systems make Type Ia supernovae.

See this article in Physics.org

CFA Press Release

In physics, the value of a theory is measured by how well it agrees with experimental data. But how should the physics community gauge the value of an emerging theory that cannot yet be tested experimentally? With no reality check, a less than rigorous hypothesis such as string theory may linger on, even though physicists have been unable to work out its actual value in describing nature.

Nature Article by Abraham Loeb

Credit: NASA/JPL-
Caltech/R. Hurt (SSC)

How did the first stars and galaxies bring the young universe out of its dark ages and into the light? Three prominent researchers, including Harvard Astronomy Professor Avi Loeb, discuss how new instruments and observational techniques may find the answer.

http://www.kavlifoundation.org/science-spotlights/searching-first-stars

NASA/Goddard Space Flight Center/Swift

The cores of most galaxies are thought to harbor black holes with masses of a million or more suns. But many remain unseen until an unlucky star passes too close and is pulled apart by tidal forces. The stellar debris gathers into a disk and spirals towards the black hole in the center. As it does, it may form a jet of material that beams high-energy light like a flashlight. Last spring, the Swift satellite measured a flare of x rays and gamma rays from a distant galaxy that has the hallmarks of such a jet that happens to point right at us.... Read more about Synopsis: Tidal Disruption of a Star (N. Stone and A. Loeb)