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Deneb is the brightest star of the [[Cygnus]] constellation (also known as the Swan) and the 19th brightest star in the night sky overall. The [[star]] itself is of spectral class A2 Ia, making it a white [[supergiant ]] star, with a surface temperature of around 8500K<ref name="uni">http://www.astro.illinois.edu/~jkaler/sow/deneb.html</ref>.

The [[star]] is estimated to be around 1,550 light years away away as measured by the [[Hipparcos]] satellite in 2007<ref>http://arxiv.org/abs/0804.2553</ref>, earlier estimates have placed the star as close as 1340 light years and as far as 1840 light years distant<ref name="uni">http://www.astro.illinois.edu/~jkaler/sow/deneb.html</ref>. Deneb is estimated to have between 20 and 25 times the [[sun|sun's]] mass, showing it to be a low density star which is expected for a supergiant. However, the size of Deneb is estimated to be 108 times that of our star, so that if Deneb was at the center of our [[Solar System]] its diameter would extent to half as far as the orbit of the [[Earth]]. The most incredible difference is that Deneb is 54,400 times as luminous as our own sun, so luminous that if the star was as close as Vega (25 light years away), it would be 15 times brighter then [[Venus]], the brightest object in the night sky (excluding the [[Moon]])<ref name="uni">http://www.astro.illinois.edu/~jkaler/sow/deneb.html</ref>.

Deneb most likely started its life as a Class B blue-white or Class O blue star some ten million years ago before passing into its present stage as a class A [[supergiant]] by consuming all its [[hydrogen]] fuel in its core. The star is burning its fuel so intensely it is losing mass at a rate a millionth of a solar mass per year, 40 million times as quickly as our own [[Sun]]. Because of this, the star will burn through its very short relative stellar lifetime , first by becoming a red supergiant and could finally ending its life [[supernova]] in a few million yearstimes<ref name="uni">http://www.astro.illinois.edu/~jkaler/sow/deneb.html</ref>.