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Amalthea - anyone viewing this?

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#1 opticsguy

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Posted 05 September 2013 - 07:02 AM

Has anyone viewed Amalthea, 5th planet of Jupiter and around 14th magnitude? What equiment did you use?

#2 azure1961p

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Posted 05 September 2013 - 07:39 AM

This is one I want to try for. Problem is getting accurate mapping. It is far enough out at times it'd seem feasible in my 8". I don't know how to obtain position ephemerides however. Safari doesn't acknowledge it.

Pete

#3 John Boudreau

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Posted 05 September 2013 - 08:43 AM

This is one I want to try for. Problem is getting accurate mapping. It is far enough out at times it'd seem feasible in my 8". I don't know how to obtain position ephemerides however. Safari doesn't acknowledge it.

Pete


Ephemerides of the gas giants are available here:
http://pds-rings.seti.org/
Direct link to the one for Jupiter:
http://pds-rings.set...iewer2_jup.html
Just be sure to include Amalthea under 'moon selection'.

BTW--- The positions of planetary moons out past 20th magnitude are available in Project Pluto's Guide 9.

#4 brianb11213

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Posted 05 September 2013 - 08:57 AM

Has anyone viewed Amalthea, 5th planet of Jupiter and around 14th magnitude? What equiment did you use?

Close in and with the full glare of Jupiter to contend with ... I reckon you'd need well in excess of 15" aperture to stand any chance at all of seeing Amalthea in the eyepiece. Mars's moons are about a magnitude brighter & at a somewhat greater seperation from the planet than Amalthea is. If you can't see Phobos & Deimos you aren't going to see Amalthea.

Webb, "Celestial Objects for Common Telescopes", fails to mention Amalthea at all - this is a reasonable indication that it isn't visible with 12" even in excellent conditions.

#5 azure1961p

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Posted 05 September 2013 - 10:10 PM

John ,

Thank you for some fantastic links, as well and unrelated to this post, the explanation of your Triton color images. Fascinating . I've got to finally get my EQ Platform completed sonI can image too. I've got a DBK that hasn't really been exploited at all. The links though - didnt kno they existed. Mucho gratis.

Brian, yes I think you may be right about the aperture needs. I thought Amalthea had some wildly large orbit that took it far enough from Jupiter - beyond Callisto anyway. If its WITHIN Callistos orbit, for me - I don't know - that's awfully challenging in the glare.


Pete

#6 brianb11213

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Posted 06 September 2013 - 04:58 AM

I thought Amalthea had some wildly large orbit that took it far enough from Jupiter - beyond Callisto anyway. If its WITHIN Callistos orbit, for me - I don't know - that's awfully challenging in the glare.

Amalthea's orbit is well inside Io ... mean distance (from Jupiter's centre) 181000 km = 2.54 Jupiter radii, eccentricity 0.003 (essentially circular). Amazingly it was discovered visually, the last satellite in the Solar System to be discovered this way. The eagle eyed E E Barnard used a 36 inch scope at a very fine site (Lick observatory) ...

#7 azure1961p

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Posted 06 September 2013 - 05:46 AM

Ah - then its way off limits . Thanks Brian.


Pete

#8 Astrojensen

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Posted 06 September 2013 - 12:33 PM

A friend of mine has seen it several times in a 16" Meade LB dob. It has eluded me in my 12" Meade LB.


Clear skies!
Thomas, Denmark

#9 Achernar

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Posted 17 September 2013 - 11:34 AM

Amalthea is well inside Io's orbit, which also puts it deep in Jupiter's glare. It was discovered with the 36-inch refractor at Lick Observatory by Edward Emerson Barnard in 1892, and the last moon to be found without the aid of long exposure photography or space probes. To see it from Earth might not require a 36-inch telescope anymore, but it would be a tough nut to crack. I have a hard time seeing Enceladus because the glare from Saturn and poor seeing can hide it. Jupiter is much brighter, and that would make seeing a 14th magnitude moon that much harder.

Taras

#10 E_Look

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Posted 17 September 2013 - 04:33 PM

I don't think I'll do it, at least not with my 8" scope from home.

#11 Darren Bly

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Posted 17 September 2013 - 05:40 PM

I saw it once thru the 36" at Lick. I asked about it and they looked it up. 45 min later it was at elongation.

#12 ValeryD

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Posted 22 September 2013 - 11:12 AM

I saw it once thru the 36" at Lick. I asked about it and they looked it up. 45 min later it was at elongation.


And how the Jupiter itself was seen through such a large refractor? Detalization, colors on the details, false color? What was the magnification(s)?

Thanks.

Valery.

#13 Wingryder

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Posted 24 September 2013 - 10:30 PM

Has anyone been able to image it with a CCD?

#14 Dave Mitsky

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Posted 25 September 2013 - 12:29 AM

This is an appropriate time of year for this topic, since Almathea was discovered in September, September 9th, 1892 to be precise.

Dave Mitsky

#15 Darren Bly

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Posted 27 September 2013 - 09:19 PM

I saw it once thru the 36" at Lick. I asked about it and they looked it up. 45 min later it was at elongation.


And how the Jupiter itself was seen through such a large refractor? Detalization, colors on the details, false color? What was the magnification(s)?

Thanks.

Valery.


I believe it was about 1100x, a 16mm Nagler 2. There was a lot of color but the image was fairly sharp. At 1100x it was very seeing limited.






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