The Andromeda Galaxy Just Had a Bright Gamma Ray Event 129
First time accepted submitter SpaceMika (867804) writes "We just saw something bright in the Andromeda Galaxy, and we don't know what it was. A Gamma Ray Burst or an Ultraluminous X-Ray Object, either way it will be the closest of its type we've ever observed at just over 2 million light years away. It's the perfect distance: close enough to observe in unprecedented detail, and far enough to not kill us all."
False alarm -- just a normal background source (Score:5, Informative)
The team which announced the event has now figured out that it wasn't interesting after all:
TITLE: GCN CIRCULAR
NUMBER: 16336
SUBJECT: Swift trigger 600114 is not an outbursting X-ray source
DATE: 14/05/28 07:57:12 GMT
FROM: Kim Page at U.of Leicester
K.L. Page, P.A. Evans (U. Leicester), D.N. Burrows (PSU), V. D'Elia (ASDC) and A. Maselli (INAF-IASFPA) report on behalf of the Swift-XRT team:
We have re-analysed the prompt XRT data on Swift trigger 600114 (GCN Circ. 16332), taking advantage of the event data.
The initial count rate given in GCN Circ. 16332 was based on raw data from the full field of view, without X-ray event detection, and therefore may have been affected by other sources in M31, as well as background hot pixels. Analysis of the event data (not fully available at the time of the initial circular) shows the count rate of the X-ray source identified in GCN Circ. 16332 to have been 0.065 +/- 0.012 count s^-1, consistent with the previous observations of this source [see the 1SXPS catalogue (Evans et al. 2014): http://www.swift.ac.uk/1SXPS/1... [swift.ac.uk].
We therefore do not believe this source to be in outburst. Instead, it was a serendipitous constant source in the field of view of a BAT subthreshold trigger.
This circular is an official product of the Swift-XRT team.
Better luck next time.
No, it's a ULX (Score:4, Informative)
http://www.star.le.ac.uk/~pae9... [le.ac.uk]
Re:False alarm -- just a normal background source (Score:5, Informative)
And here's a very nice, easy-to-understand explanation of what happened, written by one of the SWIFT astronomers:
http://www.star.le.ac.uk/~pae9... [le.ac.uk]
Woops! Nevermind. (Score:5, Informative)
This has been withdrawn. From
http://gcn.gsfc.nasa.gov/gcn/g... [nasa.gov]
We therefore do not believe this source to be in outburst. Instead, it was
a serendipitous constant source in the field of view of a BAT subthreshold
trigger.
This circular is an official product of the Swift-XRT team.
Re:far enough (Score:5, Informative)
It would instantly fry half the planet. The rest of the planet gets to die slowly.
Apparently it was a false alarm... (Score:5, Informative)