NASA renames Swift telescope to honor Neil Gehrels

NASA has renamed the Swift space telescope, designed to quickly detect and observe fast transient events in space like gamma ray bursts, to honor the late Neil Gehrels, the man who led the project from day one.

During a presentation at a NASA town hall meeting at the 231st Meeting of the American Astronomical Society here, Thomas Zurbuchen, NASA associate administrator for science, said that Swift would now be known as the Neil Gehrels Swift Observatory.

Gehrels, who died in February 2017, had been principal investigator for Swift, a mission launched in 2004. The spacecraft was designed to be able to rapidly respond to transient events, such as gamma-ray bursts, observing them at wavelengths ranging from gamma rays to visible light.

“Neil wore many hats in service to the astrophysics community,” said Paul Hertz, director of NASA’s astrophysics division, at a later press conference at the meeting. In addition to being the principal investigator for Swift, had served as project scientist on the Compton Gamma-Ray Observatory and Fermi missions. At the time of his death last year he was project scientist for the Wide-Field Infrared Survey Telescope, NASA’s next flagship astronomy mission after the James Webb Space Telescope.

Knowing astronomers, they will now refer to this observatory as the NGSO. Not I. It will be “Gehrels Swift” to me, whenever I need to mention it. Gehrels was one of the most friendly, open, and easy-to-work-with astronomers I ever had to deal with. He is sorely missed.

A bullseye in space

Cool image time! The science team of the Swift space telescope has released a movie compiled from X-ray images taken of the first outburst from black hole V404 Cygni in 26 years. [link fixed!]

Astronomers say the rings result from an “echo” of X-ray light. The black hole’s flares emit X-rays in all directions. Dust layers reflect some of these X-rays back to us, but the light travels a longer distance and reaches us slightly later than light traveling a more direct path. The time delay creates the light echo, forming rings that expand with time.

Detailed analysis of the expanding rings shows that they all originate from a large flare that occurred on June 26 at 1:40 p.m. EDT. There are multiple rings because there are multiple reflecting dust layers between 4,000 and 7,000 light-years away from us. Regular monitoring of the rings and how they change as the eruption continues will allow astronomers to better understand their nature.

V404 Cygni is located about 8,000 light-years away. Every couple of decades the black hole fires up in an outburst of high-energy light. Its previous eruption ended in 1989.

The animation below the fold is a smaller resolution version of the movie, showing the rings as they expand outward.
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Engineers have returned to full operation the x-ray instrument on the Swift gamma-ray burst space telescope.

Engineers have returned to full operation the x-ray instrument on the Swift gamma-ray burst space telescope.

They are still investigating what went wrong this week, but have figured out how to get the instrument back in full automatic robotic mode so that it can gather x-ray data on gamma ray bursts within seconds of their occurence.

Not only can the very fast rotation of neutron stars sometimes speed up suddenly, scientists have now discovered that their rotation can suddenly slow as well.

Not only can the very fast rotation of neutron stars sometimes speed up suddenly, scientists have now discovered that their rotation can suddenly slow as well.

The neutron star, 1E 2259+586, is located about 10,000 light-years away toward the constellation Cassiopeia. It is one of about two dozen neutron stars called magnetars, which have very powerful magnetic fields and occasionally produce high-energy explosions or pulses. Observations of X-ray pulses from 1E 2259+586 from July 2011 through mid-April 2012 indicated the magnetar’s rotation was gradually slowing from once every seven seconds, or about eight revolutions per minute. On April 28, 2012, data showed the spin rate had decreased abruptly, by 2.2 millionths of a second, and the magnetar was spinning down at a faster rate.

Astronomers had a theory which explained the sudden increase in a neutron star’s rotation. They don’t have one yet for why this star slowed.

Last Saturday the space telescope Swift detected the most powerful gamma ray bursts ever detected.

Last Saturday the space telescope Swift detected the most powerful gamma ray burst ever detected.

You can see the raw reports of the detection, followed up immediately by a host of other ground-based and space-based observations at this website. Click on the circulars for GRB130427A, starting with circular 14448. When this happened last Saturday I was out camping. When I got home there were dozens of circulars to look at. Based on the data here, this gamma-ray burst was relatively close for a grb, approximately 3.6 billion light years away.