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Suitable Eclipsing Binary Target

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Last post
Last seen: 7 months 4 weeks ago
Joined: 02/12/2018 - 17:20
Suitable Eclipsing Binary Target

Hi, I'm hoping to tap into your collective wisdom to help me find a suitable eclipsing binary target to be observed simultaneously from an observatory in the UK (51N, 01E) and Teide observatory (28N, 344E).  The aim is to observe a suitable target with several telescopes to determine the relative timing precision achievable.  To enable this I am looking for a star that is;

1. Visible during night hours in July/August from both the observatory locations with the lowest possible airmass.

2. Is bright enough to enable high cadence imaging with ~0.4m telescopes.

3. Has a short period ideally of just a few hours to allow observation on any clear, short Summer night.

4. Has a sharply defined eclipse to provide a small timing measurement uncertainty.

A target like the post common envelope binary NYVir would be ideal but at a higher altitude from the UK than Virgo?

Thanks in advance for your help.


Xilman's picture
Last seen: 4 hours 59 min ago
Joined: 24/03/2018 - 15:17

Have you downloaded the complete GCVS?  If so a preliminary selection based on a minimum Dec, a plausible range of RA and a type of EA, EB, ... will give you an initial range of candidates.

What do you consider high-cadence? Minutes, seconds or milliseconds?

My 0.4m telescope (located only about 100km from El Teide) could manage a very few millimags precision (unfiltered CCD, so approximately Gaia G band) down to mag 11.5 with a cadence of around a minute as demonstrated with an observation of an exoplanet transit.

In fact, why don't you try for an exoplanet transit?  Not only do you get your differential timing data, you also add to our knowedge of exoplanets.  The minimum may be wide but the ingress and egress events are short-lived and it's generally possible to observe both in a single session.

Would you like me to join in perhaps, weather permitting?  It's been unusually cloudy in these parts of late.  I also need to get the new camera commissioned first but I hope that doesn't take too long.

Americo Watkins's picture
Last seen: 11 hours 43 min ago
Joined: 11/03/2014 - 13:12
target like the post common envelope binary

Hi Mark,

I collaborate with a BAA team working on post common envelope SdB type binaries.  I've alerted them to your request, I'm sure we can provide you with a target from our list.


Last seen: 2 months 6 days ago
Joined: 05/03/2014 - 08:21
Suitable eclipsing binary target

Hi Mark

NY Vir has an issue.  It pulsates and so affects measurement accuracy.  Could try NSVS14256825 which has a +4 degree dec.  HS0705+6700 is visible from mid August with dec of 66 degrees.



eliot's picture
Last seen: 1 week 2 days ago
Joined: 08/03/2014 - 14:29

You could try using my website to search for observable candidates.  You can't specify future dates; however can update observing sites and look stars available tonight for all your sites.


Richard Miles's picture
Last seen: 14 min 47 sec ago
Joined: 07/03/2014 - 16:09
How about a fast-spinning asteroid?

Mark - I did a search for a suitable asteroid candidate but only came up with 321 Florentina 15th magnitude P=2.87 h  Ampl.=0.31-0.52 mag. So there would be a minimum every 1.5 hours or so.

This doesn't really become accessible until late September / early October. It reaches opposition in December at mag 13.8.