Paul Alsing
July 12th, 2016, 11:52 PM
Object of the Week - July 10th, 2016, CRL 2688, AFGL 2688, RAFGL 2688, PK 080-6.1, V1610 Cyg, UGC 11668, the Egg Nebula - in CYGNUS
R.A. 21h02m18.6s DEC +36°41'35" (2000)
Size: 1.0' Mag: 13.50
CRL 2688 (the Cygnus Egg) has had a bad case of mis-identification over the years, carrying labels denoting it as a variable star, a galaxy, a planetary nebula, an infrared source, and in Simbad it has about 20 designations! Megastar still calls it a planetary nebula.
Currently CRL 2688 is considered to be a bipolar protoplanetary nebula approximately 3,000 light-years away from Earth. It is basically a Sun-like star that is in the very early stages of becoming a planetary nebula, an expanding cloud of dust and ejected by a dying star that has burned most of its fuel. The Hubble has provided amazing pictures...
http://imgsrc.hubblesite.org/hu/db/images/hs-2003-09-a-print.jpg
http://imgsrc.hubblesite.org/hu/db/images/hs-1997-11-a-web_print.jpg
... and there is a lot of information on the internet explaining just what is happening here. Amazing stuff.
http://hubblesite.org/newscenter/archive/releases/1997/11/background/
http://arxiv.org/pdf/astro-ph/0309677v1.pdf
http://authors.library.caltech.edu/53934/1/36446.pdf
The Egg Nebula is a tiny little fellow and is not much to look at, visually, but learning about its true nature is a fascinating adventure. In my 25" dob it initially looked like an uneven double star of about 8" separation, but boosting the power to 300-500 diameters made each component nebulous, but still with a dark lane between them. The nebulosity around the brighter component (just east of north) smeared outwards along a line connecting the 2 lobes, quickly fading away. There is a smaller and dimmer extension from the dimmer lobe (just west of south). I tried every filter I had (OIII, H-beta, LPR, UHC) but there was no response to any of them. I can only assume that this means that CRL 2688 is mostly a reflection nebula.
Cygnus is well-placed this time of year, so give it a go and let us know!
R.A. 21h02m18.6s DEC +36°41'35" (2000)
Size: 1.0' Mag: 13.50
CRL 2688 (the Cygnus Egg) has had a bad case of mis-identification over the years, carrying labels denoting it as a variable star, a galaxy, a planetary nebula, an infrared source, and in Simbad it has about 20 designations! Megastar still calls it a planetary nebula.
Currently CRL 2688 is considered to be a bipolar protoplanetary nebula approximately 3,000 light-years away from Earth. It is basically a Sun-like star that is in the very early stages of becoming a planetary nebula, an expanding cloud of dust and ejected by a dying star that has burned most of its fuel. The Hubble has provided amazing pictures...
http://imgsrc.hubblesite.org/hu/db/images/hs-2003-09-a-print.jpg
http://imgsrc.hubblesite.org/hu/db/images/hs-1997-11-a-web_print.jpg
... and there is a lot of information on the internet explaining just what is happening here. Amazing stuff.
http://hubblesite.org/newscenter/archive/releases/1997/11/background/
http://arxiv.org/pdf/astro-ph/0309677v1.pdf
http://authors.library.caltech.edu/53934/1/36446.pdf
The Egg Nebula is a tiny little fellow and is not much to look at, visually, but learning about its true nature is a fascinating adventure. In my 25" dob it initially looked like an uneven double star of about 8" separation, but boosting the power to 300-500 diameters made each component nebulous, but still with a dark lane between them. The nebulosity around the brighter component (just east of north) smeared outwards along a line connecting the 2 lobes, quickly fading away. There is a smaller and dimmer extension from the dimmer lobe (just west of south). I tried every filter I had (OIII, H-beta, LPR, UHC) but there was no response to any of them. I can only assume that this means that CRL 2688 is mostly a reflection nebula.
Cygnus is well-placed this time of year, so give it a go and let us know!