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Observation by Nick Hewitt: Omicron -2 Eridani: no ordinary triple

Uploaded by

Nick Hewitt

Observer

Nick Hewitt

Observed

2018 Nov 17 - 23:48

Uploaded

2018 Nov 19 - 17:00

Objects

Keid

Planetarium overlay









Constellation

Eridanus

Field centre

RA: 04h15m
Dec: -07°40'
Position angle: +4°06'

Field size

0°26' × 0°21'

Equipment
  • TMB 115mm f7 triplet
  • Trius 814 CCD
  • EQ8 mount
  • Astronomik RGB filters
Exposure

RGB 10 x 30 sec each averaged

Location

Northampton

Target name

40 or Omicron-2 Eridani (Keid)

Title

Omicron -2 Eridani: no ordinary triple

About this image

The primary is an undistingished 4th magnitude K-type star low down in the Celestial River; but at 85" distance lie a closer pair that represent the easiest white dwarf and one of the easiest red dwarfs to observe. They are far enough away from the primary that glare is not an issue (unlike the Pups of Sirius and Procyon). Omicron-2B was the first white dwarf to be recognised as such. Omicron-2C is not the brightest red dwarf by any means, but its location makes pinning it down easy. BC are at 8" separation, with a 240 year orbit. Enlarge image to bring out the red dwarf's colour. 

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