The NASA/ESA Hubble Space Telescope has captured a new photo of a stunning and slightly eerie nebula called IC 63.
IC 63 is classified as both a reflection nebula (as it is reflecting the light of a nearby star) and as an emission nebula (as it releases hydrogen-alpha radiation); both effects are caused by the gigantic star Gamma Cassiopeiae; the radiation of this star is also slowly causing the nebula to dissipate. Image credit: NASA / ESA / Hubble.
IC 63 is located in the constellation, Cassiopeia, approximately 550 light-years away.
Also known as the ‘Ghost of Cassiopeia,’ the nebula is being blasted by a torrent of radiation from a nearby, blue-white subgiant variable star called Gamma Cassiopeiae.
This star is 19 times more massive and 65,000 times brighter than our Sun.
It also rotates at the incredible speed of 0.93 million mph (1.6 million km per hour) — more than 200 times faster than our parent star. This frenzied rotation gives it a squashed appearance.
The fast rotation causes eruptions of mass from the star into a surrounding disk. This mass loss is related to the observed brightness variations.
The colors in IC 63 showcase how the eerie nebula is affected by the powerful radiation from the distant star.
The hydrogen within the nebula is being bombarded with ultraviolet (UV) radiation from Gamma Cassiopeiae, causing its electrons to gain energy which they later release as hydrogen-alpha radiation — visible in red in this Hubble image.
This hydrogen-alpha radiation makes IC 63 an emission nebula, but we also see blue light in this image.
This is light from Gamma Cassiopeiae that has been reflected by dust particles in the nebula, meaning that IC 63 is also a reflection nebula.
IC 63 is slowly dissipating under the influence of UV radiation from Gamma Cassiopeiae.
However, this colorful and ghostly nebula is not the only object under the influence of the mighty star.
It is part of a much larger nebulous region surrounding Gamma Cassiopeiae that measures approximately two degrees on the sky — roughly four times as wide as the full Moon.
