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Ep. 27, Page 8
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Comic 1957 - Ep. 27, Page 8

24th Aug 2015, 10:29 PM in Episode 27 :: Save My Place | Load My Place
Average Rating: 5 (2 votes)

Author Notes:

smbhax 24th Aug 2015, 10:29 PM edit delete
smbhax
A couple years ago, a magnetar was discovered very close to the supermassive black hole (called "A*") at the center of our galaxy: the source of a powerful X-ray burst detected by Swift on April 24, 2013 (source), having a larger Faraday rotation (magnetic polarization of light) than any other detected source in our galaxy besides A* itself (source), was eventually deduced to have come from a previously unknown magnetar, designated SGR J1745-2900 ("SGR" stands for soft gamma repeater, a class of objects that emit gamma and/or X-rays at irregular intervals). An estimate (source) places SGR J1754-2900 at roughly 0.1 parsecs—about 1/3rd of a light year—from A* itself.

The Wikipedia page for SGR J1745-2900 says it is the first discovered magnetar, which is very incorrect: the first magnetar (magnetars are neutron stars—remnants of stellar collapses that weren't quite massive enough to break standard laws of physics and collapse completely into black holes—with extremely powerful magnetic fields) was discovered in 1979. I think, then, that claim on the Wikipedia page is just the result of a misplaced comma, and it's trying to say that it is the first magnetar (out of the 24 or so known magnetars) discovered in orbit around a black hole, implying that it is orbiting A*; this has not yet been proven conclusively, especially given the uncertainty of the exact distance (and even at 0.3 light years, A*'s gravitational effect on the magnetar would be "small"), but further observation (here, for instance), suggests that SGR J1745-2900 likely *is* part of the group of very massive young stars in wide orbits around A*; that won't be known with certainty, though, until later observations can be used to calculate the magnetar's acceleration, because it is still possible that it is accelerating fast enough to break A*'s gravity and move out of the galactic core.

Comments:

cattservant 25th Aug 2015, 2:23 AM edit delete reply
cattservant
Welcome Wagon!
smbhax 25th Aug 2015, 8:52 PM edit delete reply
smbhax
: o
moizmad 25th Aug 2015, 10:54 AM edit delete reply
moizmad
Is that a really big ship or a really small planet?
smbhax 25th Aug 2015, 8:52 PM edit delete reply
smbhax
Nah! ^_^