Waid Observatory

Object: Abell 85 / CTB1

Date: Ocr. 11/12, 2022   -    Location: Davis Mountains west of Fort Davis, TX
Telescope: TeleVue 100mm Genesis    -    Mount: Paramount MYT   -  Camera: SBIG ST-8300M
Exposure: Ha & OIII = 21x20 min. each  Binned 1x1  R,G,B for stars = 6x5 min. each   Binned 2x2
Total intergration time = 15.5 hours.

Click on the image to view at higher resolution.

Abell 85

Abell 85 - Supernova Remnant in Cassiopeia

Abell 85, also known as CTB1, is a faint supernova remnant1 located in the northern constellation Cassiopeia approximately 9800 lightyears distant1.  Until 1971 it was considered a planetary nebula and was included in the Abell Catalog of Planetary Nebula as number 851.  In 1971 Willis and Dickel confirmed that Abell 85 was actually a supernova remnant1.  The supernova event that created the nebula occurred approximately 10,000 years ago2.  This supernova produced a high-velocity radio pulsar3,4 (PSR J0002+6216).  This pulsar has a measured transverse velocity of 1100 kilometers per second3 and has already exited the nebula2 where it was created.  An image displaying the position of the pulsar may be viewed here.

The image above was captured using Ha (Hydrogen Alpha) and OIII (Doubly Ionized Oxygen) narrowband filters.  The image was assembled by mapping Ha to red and OIII to green and blue.  The stars were overlaid with RGB filtered data to give them a near true color appearance.

1Metsavainio - https://astroanarchy.blogspot.com/2015/02/abell-85-ctb1-dim-galactic-supernova.html
2NASA APOD Oct. 2, 2022 - https://apod.nasa.gov/apod/ap221002.html
3F.K. Schinzel, et al, 2019 - https://arxiv.org/pdf/1904.07993.pdf
4Pulsars - https://en.wikipedia.org/wiki/Pulsar

Copyright Donald P. Waid