Our nearest spiral galaxy neighbor, M31, has diffuse bulge emission and probablyhas an extended diffuse halo of hot gas, similar to that seen in other spiralgalaxies. Unlike more distant spirals, where halo gas observations arephoton-starved, a M31 halo will not suffer this problem, allowing the gasdistribution to be measured and the temperature to be mapped with unprecedentedaccuracy. This will define halo gas properties, the disk-halo interface and itwill be a powerful test of models. This X-ray halo can have a radial extent of 1degree (10-15 kpc), so a mosaic of observations will be constructed along theminor axis, leveraging existing observations. By using overlapping fields, wewill flat-field the data to the necessary precision.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2006-07-03T08:07:19Z/2006-07-03T21:02:44Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Prof Joel Bregman, 2007, 'An Extended Hot Halo Gas Around M31', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-q83cghz
