First ever Neptune + (Video) Image

[Macavity]

Since I'd never seen Neptune via any method, thought I'd have a go at video snapshot imaging Neptune with my Watec 120N+ and TS 8" F4 Photo-Newt. Still having modest troubles with GoTo accuracy, so decided to "Synch" on as many stars close to Neptune as possible. With the Watec in longer integration mode (5s here), I'm usually looking at stars down to mag 12+ in real time. Stacking (and various knob twiddlings) goes a fair bit deeper of course, but not this time. I just took a series of snapshots and worked on these this afternoon.

With a bit of judicious rotation, I started to get good matches re. the images of 57 & 58 Aqr (plus their surroundings) with Stellarium screenshots. A tad easier than doing this in real time! What I believed to be Neptune had rather few stars above mag 12 around... So, had I really "seen" Neptune? I felt I shouldn't cheat with such an important matter!

So, in real time, with field approx. 30' x 20' Neptune appears to be sitting on a diagonal between TWO brighter stars [A & B] with a fainter, nearer neighbour [C], to one side! Of course, as is the way with Video cameras, there are a few "hot pixels" at high integrations. But these can usually be distinguished by their more oblong shape. Perhaps better seen (worked with) in the negative image...

Here I have made a tentative identification of the stars from the corresponding Stellarium screenshot:

"Honest Macavity" then got his ruler out and measured the distances between "Neptune" and stars A, B and C etc.

Remarkably, there is geometrical agreement to 1mm in 10cm (1%) - So it appears this is / was indeed Neptune!

At the end of imaging, I did take time to remove the Watec and look through the scope visually. I recognised the asterisms associated with 57 & 58 Aqr, but then "got a bit lost" on the way to Neptune. <sigh> I've still to conquer visual Astronomy?

P.S. Stellarium helpfully marks Nereid and Laiomedeia [Neptune XII apparently!] - Those are naturally well out of range. But I might replace the Newt with the MAK 150 and have a go at Triton next. Should be pretty much in range at mag +13.5. Who knows...

[kirkster501]

Well done. Very interesting and thanks for sharing.

[Polar Bear]

looks convincing to me, well done, I fancy a 'go' at Neptune myself at the Cumbria Star Party in August.

[Superdavo]

Well done. I've seen Neptune by myself (It was in a close conjunction with Venus), and it was a rather inconspicuous blue dot, so it's not easy to find, so well done for catching it!

[WaveSoarer]

That's a very nice report and many thanks for sharing this.

[Macavity]

Thanks folks. Might pave the way for another "ambition" - Minor Planets?

I suppose one "pale blue dot" does look much the same every another.

But I got excited - Not least by the possibilities of combining techniques...

I see (next day) the path of Neptune (relative to 57 / Sigma Aquarii) over the

months of July and August figures (sic) in the SPA's Popular Astronomy. Not

to forget June's AN too. Should take more notice of such things in future.

Shame Uranus & Neptune seem to be in the nether regions of the Zodiac...

[Phil Fargaze]

Nice bit of planet chasing there. I have captured a few asteroids with my Watec 120. I usually get a 30 to 60 second capture then do another about half hour later. This is usually enough to produce two images which reveal the motion of the asteroid.

I would like to have a try for Pluto with the Watec but I need to check if it is not too low for me.

[LukeSkywatcher]

Ive always thought and read that Neptune would appear like a star in even the biggest of back garden scopes. Your image size is very impressive. Its clearly a planet and not a star.

Very well done.

[Macavity]

Nice of you. But I fear, in a field 30' across, a 2" disk should be less than a pixel across?

CCD "blob" size is a function of brightness with (here) a bit of dodgy collimation thrown in...

[guv]

Looks good to me. I'd feel quite chuffed if I'd done that.