Observation by Paul Leyland: LS And at minimum
Uploaded by
Paul Leyland
Observer
Paul Leyland
Observed
2019 Dec 28 - 22:00
Uploaded
2020 Jan 03 - 19:58
Planetarium overlay
Constellation
Eridanus
Field centre
RA: 03h56m
Dec: -02°49'
Position angle: +49°21'
Field size
10° × 6°
Equipment
- 0.4m Dilworth-Relay
- SX Trius Pro 814
- Johnson-V filter
Exposure
4860s in 30s subs
Location
Tacande Observatory, MPC J22
Target name
LS And
Title
LS And at minimum
About this image
Jeremy Shears and I have recently had an email discussion concerning the ability of amateurs to perform precision photometry of faint objects. Purely for the fun of it, I took 80 minutes worth data on LS And through a Johnson V filter. I'd not usually spend that much time for anything but astrometry and then it would be unfiltered for maximum sensitivity.
LS And is a UGWZ eruptive which spends most of its time at minimum, that is with a B-magnitude around 20.2 according to the AAVSO. Jeremy mentioned that he had never managed to image it.
The image above shows LS And and the AAVSO sequence stars labelled. The variable is clearly visible in the image above but, alas, the SNR is such that it can not be measured to the precision (0.15 magnitude) where I would submit it to the VSS database. Three hours of data through a V filter, or 90 minutes unfiltered, would likely have been sufficient.
Files associated with this observation
Like this image
Comments
A more careful selection of the aperture diameters in APT has given a measurement of v=19.068 ± 0.149 so it just squeaks through.
The take-home message is that amateurs can now perform precision photometry down to twentieth magnitude as long as the target is thought worthy of an observation which is several hours long.
Copyright of all images and other observations submitted to the BAA remains with the owner of the work.
Reproduction of work by third parties is expressly forbidden without the consent of the copyright
holder. By submitting images to this online gallery, you grant the BAA permission to reproduce them in any
of our publications.
