Asteroid (156) Xanthippe occults star Monday Oct 29 at 1919UT)

[Helen]

Got this from the BAA Observer Alert: Asteroid (156) Xanthippe occults mag 12 star next Monday evening (Oct 29 at 1919UT)

The 125-km wide main belt asteroid (156) Xanthippe will occult a 12th magnitude star in Aquila as seen from parts of southern UK and northern Europe. See:
http://www.asteroidoccultation.com/2018_10/1029_156_57004.htm

Finder charts are available via the above link.
The star is UCAC4-409-131091 (R=11.9, V=12.5)
RA(2000): 20 28 11.61  Dec(2000) -08 13 04.5
(aka GSC 5754 0239)

The event occurs on the evening of Monday, October 29th at 19:19:13s UT (prediction for Reading, Berkshire). Observers should aim to record/monitor the star from 2 minutes before to 2 minutes after the expected mid-time i.e. 19:17-19:21 UT. Maximum duration of the occultation is expected to be about 7 seconds. The wide shadow track passes over southern England and timing observations are invited, both digital and visual. At the time, the star will be at an altitude of about 30deg in the SSW direction. The star will virtually disappear when occulted, and nearby stars should be used as comparisons.

Timing the disappearance and duration of the occultation to an accuracy of +/-0.2 sec UT or better is requested. The occulted star is not particularly bright, but the prediction is a certainty so it is a good opportunity to see an occultation at a convenient time in the evening, weather permitting. The event is attracting observers across Europe and the UK, so this is a very favourable event with a good chance of combining many timing chords to produce an accurate silhouette of the occulting body. The path covers the area of mid-Wales to Cornwall in the West, and East Anglia to Kent in the East.

The nearest 9th mag star is TYC 5754-516-1,  16' arc due west of the occulted star.

Further details including a map of the shadow track can be found on the ARPS website:
https://britastro.org/node/16174

Good luck and clear skies to all observers

[David Levi]

I thought that I would have a go at seeing this occultation with full knowledge that a magnitude 12 star is on the limit of what I can see with my 8" reflector from my suburban location.

It took me about 30 minutes to locate the star which I could only hold in view with averted vision for a limited period of time, a few seconds, before I had to refocus my eyes on another faint star and then use my peripheral vision again. I thought that it would be impossible to concentrate and hold the star in vision well enough to see the occultation rather than a loss of peripheral vision and that proved to be the case. The allotted time came and went and I couldn't see any change in my view.

Still I thought that I did well to find the star in the first place and it was an enjoyable hunt.

[mdstuart]

David

Same here. Found the star but I cannot say I saw the occultation. It did dip out but I think that was when the star was in my blind spot..

Mark

[Stu]

Sounds like a tough ask, well done for tracking the star down anyway.

@Helen thanks for posting, any future ones I will have a go at if possible.

[domstar]

@David Levi A wonderful post that really sums up stargazing for me. Totally bonkers but makes sense to everyone on this forum. This should be the first post every newcomer reads before they take the plunge on their first equipment.

The things we do for entertainment.

[domstar]

14 hours ago, David Levi said:

I thought that I would have a go at seeing this occultation with full knowledge that a magnitude 12 star is on the limit of what I can see with my 8" reflector from my suburban location.

It took me about 30 minutes to locate the star which I could only hold in view with averted vision for a limited period of time, a few seconds, before I had to refocus my eyes on another faint star and then use my peripheral vision again. I thought that it would be impossible to concentrate and hold the star in vision well enough to see the occultation rather than a loss of peripheral vision and that proved to be the case. The allotted time came and went and I couldn't see any change in my view.

Still I thought that I did well to find the star in the first place and it was an enjoyable hunt.

 A wonderful post that really sums up stargazing for me. Totally bonkers but makes sense to everyone on this forum. This should be the first post every newcomer reads before they take the plunge on their first equipment.

The things we do for entertainment.

 

(sorry for the duplicate post- I wanted to quote but I did it wrong.)Please delete the previous post if that's appropriate.

[David Levi]

Thanks Dom @domstar . Yes, it was in one of Neil @Littleguy80 's points in his recent post about what experience has taught him. Star hopping on a hunt for an object to view is great fun whether you find the object or not. Although finding your target is better than not finding it ?.

 

[domstar]

@David Levi There's star hopping and there's spending half an hour finding a star you can't see directly in order to see it dimmed by an asteroid beyond the limits of vision. You get bonus points for being unsuccessful. It just shows how far you've come. I'm guessing that you never could have imagined doing this when you first started (I know you've been doing this longer than me).

I thought spending a large part of multiple sessions staring at the space where M74 should be was hard core but this is a few steps further.

Anyway, hats off to your tenacity and to SGL for enabling new and obscure delights.

p.s at some stage I'd like your opinions on your Tak vs 200p and what you do with both but this is probably not the place.

 

[David Levi]

I know what you mean Dom @domstar. That 30 minutes may seem a lot but it wasn't frustrating at all. When you're in the mood the time flies by especially when you're concentrating and have a goal to get to. I think that the gratification of finding an object is greater if you've spent a bit of time looking for it and it's an excellent way to learn the sky without trying.

No, I don't think I had much of a clue what was involved in amateur astronomy before starting. I just knew that it was something that it was high time to do.

With regards to the Tak vs the 200P, it is still early days and I'm a bit handicapped with magnification at the moment due to the difference in focal length of the telescopes and my eyepiece range. My Barlow isn't good and so I don't like using it. I think I need a Televue Powermate - more money to spend ?.