Trapezium E & F stars

[John]

I still can't make out either in my Vixen 102ED but E & F with my 8" dob on a number of nights now. Orions belt does sit right over my neighbours house though so I'm viewing though their heating "plume" for much of the time.

John

[lunator]

John

The seeing over your neighbours house will be pretty poor.

I always have to wait for the star to be vaey close to the meridian to spot them. I have put this down to the fact that the seeing in London is never great.

Cheers

Ian

[themos]

Tuesday night I tried to find E&F at x312 with the 12" ; couldn't see them. Good clarity, less LP that I'm used to (5 stars in the Pegasus square) but either the collimation or the seeing were taking their toll.

[GazOC]

I tried tonight under good seeing with an ED100 at x200-250 and couldn't see the F, I MIGHT have seen the E flicker in and out but I couldn't swear on it.

[Lady Isabella]

Took my 4 inch f/8 APO out in the early morning hours.

Seeing conditions were poor to start with, but did manage to glimpse star E and F.

By 02:30UT the seeing was much better. At 82x, I thought I could detect star E, going to 109x did confirm that it was E.

At 136x, I could see both E and F very well indeed. Both stars were always present, however F was harder due to its location near to star C.

Finshed off with Rigel, I could easily see the companion at 82x. Also managed to see the companion of the variable star eta Gem.

[John]

John

The seeing over your neighbours house will be pretty poor.

I always have to wait for the star to be vaey close to the meridian to spot them. I have put this down to the fact that the seeing in London is never great.

Cheers

Ian

I agree Ian but I've not got much choice where I am - given that I'm stuck with that I'm pretty pleased that I can see the E & F stars with my 8" at all.

John

[lunator]

HI John

Sorry to hear that .

Must be a real pain to have your view ruined like that.

Maybe you could help your neighbour improve his loft insulation

Cheers

Ian

[A McEwan]

G should be easy enough too with a 16", given good seeing. I've seen it in a 12" on a very good night.

[John]

HI John

Sorry to hear that .

Must be a real pain to have your view ruined like that.

Maybe you could help your neighbour improve his loft insulation

Cheers

Ian

Thanks for the sympathy

It can't be too bad though - managed to pick out the E componant with my Vixen 102ED and a 7mm Nagler T6 tonight. It came and went a bit but was definately there during the moments of best seeing

John

[Merlin66]

Hartung, in his " Astronomical Objects for Southern Telescopes", p172 comments that he could easily find E with a 75.5mm, and E and F with a 105mm.

He also says that John Herschel ( who discovered F in 1830) said in 1849 that the Trapezium stars are " accompanied by two excessively minute and very close companions, to perceive both is one of the severest tests which can be applied to a telescope"

Hartung puts this difficulty down to the low altitude from Slough (33 deg)

[Chris Rowland]

I happened to be out with my NS11GPS last night. E and F were both easily visible using a 12.5mm Plossl EP. It was nice and clear, M42 was as high as it gets and seeing seemed pretty good.

I'd suggest not using too much magnification, enough to get plenty of room between the Trapesium components, not more. This will help to keep the small stars small and may help tomake them visible.

Fired with enthuiasm I tried Sirius B but couldn't see it, even with a 6mm EP.

Chris

[Doc]

At last I bagged the E star it was clearly visible in my 12.5 orthoscopic at x146.

I managed a elongation with stars C and F using my 6mm Orthoscopic at x304 but couldn't get a clean split. Will leave this for another day. Still say dobs are not made for splitting stars you cannot beat an APO for this stuff.

[calibos]

I've seen the E star in my Orion XT12i dob regularily but never did see the F. With my new 16in Lightbridge I saw the E star the other night at a 'darker' sky observing session. Still couldn't see F. Now I know why!!

I was looking for F beside B all along !! DOH!

[Doc]

I've seen the E star in my Orion XT12i dob regularily but never did see the F. With my new 16in Lightbridge I saw the E star the other night at a 'darker' sky observing session. Still couldn't see F. Now I know why!!

I was looking for F beside B all along !! DOH!

LOL

E is beside A and F is beside C.

F is hard to spot as C is the brightest and F gets swallowed in it's glow.

[John]

E is beside A and F is beside C.

F is hard to spot as C is the brightest and F gets swallowed in it's glow.

Post that on a non-astro forum - they won't know what we are on about

John