LSR0602+3910 - Brown Dwarf in Auriga

Dear friends ... and Dave Grennan,

I am delighted to present you with what I believe is the first amateur astrophoto of a brown dwarf! Please find attached a link below to an image of LSR0602+3910 in Auriga which was originally thought to be a high proper motion star (Lepine, 2002) and which was later confirmed to be a brown dwarf (Salim, 2003).

With a visual magnitude of 20.88 (Salim, 2003), this is no easy object to either observe or image and I had to wait for this brown dwarf to be directly overhead during an evening with very good transparency and reasonable seeing (FWHM ~ 3.1"). Furthermore, the nature of this brown dwarf (type L) is that it is brightest in the infrared portion of the spectrum and which explains my inability to get a favourable result in any of the three channels of the visual part of the spectrum.

Further details along with an image at www.perseus.gr/Astro-Star-Dwarf-LSR0602+3910.htm

great work anthony,
it is amazing how deep amateurs can get with todays equipment. keep up the good work, your setting the high standard the rest of us have to follow.
stephen.

:shock: that's some impressive imaging!

I never thought I'd see the day when amateurs got down to magnitudes below 20!

Congrats!

Bart.

WOW :shock: Anthony

Congratulations Anthony! I can appreciate the successful attempt you had to make in order to obtain a magnitude threshold for a target of this nature.

Because the target is in the Red/IR region, was it really neccessary to use the other channels; eg. blue channel, where the magnitude of the target would have been much fainter? Also, is there any gain in doing short exposures and then stacking them. I have tried this out before and I have found I can achieve better results by just doing one long exposure, assuming I know the magnitude threshold already via an (OMT) observing magnitude test' and the tracking is within +/- 0.5 arc sec.

I regularly use 'observing magnitude test' (OMT) before carrying out any long exposures of faint targets. I use a sequence of exposures which then determines on a graph where the threshold occurs. Then I apply this specific long exposure to achieve the end result.

Eamonn A

Anto as usual you are pushing the limits of your set up. Well captured mate.

Eamonn do you have a link to a software routine that does OMT or is it trial and error.