all Stephen Murray stories

Young pulsar reveals clues to supernova

70652986 — Mon, 26 Mar 2007 05:15:39 -0400

Using the Chandra X-ray Observatory to learn more about pulsars, A team led by Stephen Murray of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., studied 3C58, the remains of a supernova observed on Earth in 1181 AD in the constellation Cassiopeia. 3C58 is one of the youngest known pulsars, and behaves quite differently from the better known pulsar in the Crab Nebula, which is about the same age. The observations of 3C58 will enable scientists to better understand how neutron stars are formed in the seconds just before a supernova explosion, and how they pump energy into the space around them for thousands of years after the explosion. 3C58 is a neutron star rotating 15 times a second, which means it is rotating at about half the rate of the Crab Nebula pulsar.

Uncovering new evidence for 'event horizons' surrounding black holes

70652986 — Mon, 26 Mar 2007 05:04:29 -0400

With results that fundamentally differ from earlier black hole studies, Harvard researchers have shown that some recently discovered black holes are not only ultra-dense, but actually possess event horizons that "vacuum up" energy from their surroundings. "Watching matter flowing into a black hole is like sitting upstream of a waterfall and watching the water seemingly vanish over the edge," said Ramesh Narayan, chairman of the Harvard Astronomy Department. The astronomers used NASA's Chandra X-Ray Observatory to study some of the darkest black holes yet observed. They strongly confirmed the reality of the "event horizon," the one-way membrane around black holes predicted by Einstein's theory of relativity.

Cosmic 'superbubbles' bespeak toil and trouble

70652986 — Mon, 26 Mar 2007 05:09:46 -0400

The merging Antennae Galaxies in constellation Corvus are producing massive bubbles of expanding X-ray-emitting gas at such astonishing rates that they are bumping into each other. Giuseppina Fabbiano, Andreas Zezas and Stephen Murray of the Harvard-Smithsonian Center for Astrophysics used NASA's Chandra X-ray Observatory to capture in unprecedented detail this phenomenon. Fabbiano said that the observations provide a nearby example of the what it was like 15 billion years ago when our universe was young and galaxies were just forming. "Galaxies were much closer together then," explained Fabbiano. "Collisions like the ones that produced the Antennae were much more common, and played a major role in shaping the galaxies we see around us today."

Nebula resembles gigantic cosmic crossbow

70652986 — Mon, 26 Mar 2007 05:09:50 -0400

NASA's Chandra X-ray Observatory captured the details of a compact nebula that resembles a gigantic cosmic crossbow. The nebula, located in the Vela supernova remnant, is created as a rapidly rotating neutron star, or pulsar, spins out rings and jets of high energy particles while shooting through space. The X-ray jet can be traced all the way into the neutron star, and an inner ring is seen for the first time. This ring is thought to represent a shock wave due to matter rushing away from the neutron star. More focused flows at the neutron star's polar regions produce jets of particles that blast away at near the speed of light.

Chandra finds "cool" black hole at heart of Andromeda Galaxy

70652986 — Mon, 26 Mar 2007 05:09:56 -0400

A team of scientists from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., reported that the gas funneling into a supermassive black hole in the heart of the Andromeda Galaxy, designated as "M31," is a "cool" million degrees Celsius. This unexpected result adds one more quirk to the strange behavior previously observed at the center of M31. NASA's Chandra X-ray Observatory took its first X-ray picture of the Andromeda Galaxy on Oct. 13, 1999. More than 100 individual X-ray sources were seen. One of these sources was at the previously determined position of the central supermassive black hole, which has the mass of 30 million suns.