Right area for Pluto ?

[Davey-T]

Aimed at Pluto with GOTO this morning about 1.30am, using 10"SCT  and DSLR at prime focus and took a few snaps.

Been trying to work out where it should be from star charts and Stellarium but I never seem to be able to match images to star charts.

This area seems to resemble star chart somewhat, does anybody think it's the right spot in the circle, or anywhere else in the image? if so will try again using Powermate.

Tricky conditions low down through atmosphere so not expecting much, be nice to catch it though.

Dave

[Martin Meredith]

Dave, in case it is of any help, here's a map showing a 2 degree field around the location of Pluto at 1.30 am last night (cross-checked with SkySafari3). Stars plotted down to mag 16. The tip of the red arrow is where Pluto ought to have been (Pluto is not plotted). North is up.

Now it is just an exercise in mental gymnastics to see if your chart is somehow related to this one. A kind of SGL "spot-the-ball"… Do you have an idea of your FOV and orientation?

pluto2deg.pdf

BTW this is the SkySafari screenshot corresponding to the central region of my map. The highlighted star is DON 938 in my map. Supposedly SS is plotting down to mag16 but that doesn't appear to be the case.

cheers

Martin

[Davey-T]

Thanks for that Martin, I flipped it in both directions as it was on the SCT with no diagonal. was that right ? FOV according to Stellarium about 30' by 20'.

Dave

[Tommohawk]

Have had fun with this sort of thing before. I cant see where your image area is though.

If you could get Stellarium image same scale/size then try mapping the two images using Deep sky stacker - might that work? It would show rotation required for alignment - does that make sense?

[Davey-T]

Tried that, the stars in the sky never seem to match images.

Dave

[mdstuart]

Martin...your map looks right and matches my visual observation but it's missing quite a few mag 13 14 stars.

[Martin Meredith]

Martin...your map looks right and matches my visual observation but it's missing quite a few mag 13 14 stars.

Hmmm. It might be the symbol size mapping isn't quite right for these magnitudes. The scale is nonlinear and there is a steep transition at mag 13-14 actually, but this is something I ought to change. Thanks for the heads up.

Alternatively, I have noticed issues with the catalogue I'm using (PPMXL) in star-dense regions. Either way, I'm working on it for the next version.

Martin

[Martin Meredith]

Have had fun with this sort of thing before. I cant see where your image area is though.

If you could get Stellarium image same scale/size then try mapping the two images using Deep sky stacker - might that work? It would show rotation required for alignment - does that make sense?

Agree it is a lot of fun and probably good anti-ageing mental exercise… and try as I might I can't spot the field. Another option is to submit the image to astrometry.net?

Martin

[Davey-T]

According to Stellarium this is the FOV of my camera / scope combo, I Gotoed to Albacdah 41Sgr first which was spot on in the centre and synced on it then GOTOed Pluto which in theory should be in the centre of my pic', may be too dim to show up, but there are lots of stars around the same mag visible.

Camera is parallel to RA and has auto rotate turned off so I think I need to flip the image both ways, is this right ?

If the Sun comes out later I'll do a white light so I can confirm this on the sun spots.

On Martins SkySafari map there is a small Hercules type asterism bottom right which resembles one in my image but I can't match any thing else.

Dave

[mdstuart]

Dave I put your image in this web site and it confirms you are in the right area....ish but Pluto was off the bottom left of your image!

http://nova.astrometry.net/user_images/719623#original

Center (RA, Dec): (284.660, -20.928) Center (RA, hms): 18^h 58^m 38.307^s Center (Dec, dms): -20° 55' 40.885" Size: 27.9 x 18.6 arcmin Radius: 0.280 deg Pixel scale: 1.9 arcsec/pixel Orientation:

Up is 8.94 degrees E of N

The brighter star of the pair at the bottom left is this one....

Star
TYC 6294-2251-1
Information from catalog: TYC
Tycho2 catalog
Visual magnitude: 10.41
Colour index: 0.99
Blue magnitude: 11.57
Proper motion in right ascension: -3 [mas/y]
Proper motion in declination: -9 [mas/y]

Coordinates: Apparent
Apparent RA: 19h00m05.660s DE:-20?48'10.16"
Mean of the date RA: 19h00m06.637s DE:-20?48'17.38"
Astrometric J2000 RA: 18h59m12.851s DE:-20?49'35.19"
Ecliptic L: +284?01'53" B:+01?54'12"
Galactic L: +15?01'05" B:-10?58'22"

Visibility for your observatory:
Bristol 2015-01-31 23h42m47s ( GMT )
Universal Time: 2015-01-31T23:42:47 JD=2457054.48804
Local sidereal time:08h15m57s
Hour angle: 13h15m 51s
Azimuth:+32?52' 19"
Altitude:-55?43'07"
Rise: 6h19m Azimuth+123?53'
Culmination: 10h29m +17?48'
Set: 14h39m Azimuth+236?07'

So down and left a bit and you will find Pluto.

Also your pic only goes to mag 13 so you might need a longer exposure slightly or some stacked images.

Mark

[Davey-T]

Thankyou very much for that Mark, will have another go but weather not looking too promising, cloudy last night, planning to use 2X Powermate when I think I'm in the right area, star charts are even more confusing through the eyepiece especially with small FOV.

Not expecting to resolve the heart shape but a fuzzy blob would be nice for the record

Dave

[happy-kat]

Off to of head those stars the pattern reminded me of one odd the nights when trying to find Lovejoy in caseopia.