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March 9th: Regulus to be occulted briefly ?

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Tim Haymes's picture
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March 9th: Regulus to be occulted briefly ?

Asteroid (2589) Daniel is predicted to occult Regulus on March 9th between 2020 and 2022UT centred at 2021:02s +/- 4sec. for observers in Southern England and Europe.   

Bright star occultations are rare, and observing them even more so.  Here is an opportunity that could be recorded with DSLR video or maybe a mobile phone.  A meteor detection camera would be suitable. The small asteroid has a diameter of 9 Km and subtends 6.0 mas on the sky. Regulus has a diameter of 1.4 mas, so an occultation would be brief and total with a maximum duration of 0.9 sec.  Regulus will blink out.  

On the attached map is the predicted shadow path between the blue lines and the uncertainty region between thick red lines.  

If you get a break in the cloud, and you are anywhere in the observation zones, please try a recording. Starting the recording at a known UT time point will help comparison of any successful observations and preclude spurious recordings. The chances of detection are small, but with enough observers, one could be lucky. 

Prediction update on asteroidoccultations.com: The area of likely visibility is displaced southward. All observations welcomed.

https://www.asteroidoccultation.com/2021_03/0309_2589_74114.htm

[ Additional information given kindly by: D.Herald, J.Lecacheux, K.Guhl, C.Weber, O.Kloes (IOTA-ES)]

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Regulus occultation

Hi Tim,

Thanks for the heads up for this! Alas I was too far north (which saved me some frustration as I would have been clouded out anyway). Did anyone get any positive observations? I'd love to see some results for this.

Philip

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Joined: 01/04/2020 - 13:13
Regulus Occultation

H Tim,

My observatory is in Deal which was within the red boundary bars for this occultation. It was a bit of a 'first light' experience for my new video camera. Beautifully clear skies. We managed to get set up and recording using the Watec 910 and a 50mm camera lens, So I have a video encompassing the predicted event. Very exciting as it shows stars to 10th mag and a satellite passing through about 8th mag. Playing it back at slow speed I can confirm there was no occultation visible from here. Very pleased to report, even a negative report is useful.

Not within the red bars on the update... shame!

Alan

Tim Haymes's picture
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No occultation recorded

Thank you Philip and Alan for your observations. The movement of the path is typical of predictions for higher numbered asteroids.  Sometimes this can favour an observing location.

There have been a number of MISS reports (no occultation) from observers in SE UK and Europe.  Observers who happened to be in or close to the predicted shadow were clouded out this time, and no observation made.  Two observes in England detected small drops in the light curve, and these were attributed to cloud passing, since the time of these obscurations were outside the expected occultation window.  

Thank you to all observers, and i expect there will be more bright star events in the future.

The Asteroids and Remote Planet Section (ARPS) has a group of observers making regular recordings of fainter star predictions. ( Magnitudes in the range  10-14 ).    More than 50 stellar occultations were reported (positive) last year.

Tim Haymes's picture
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WAT 910

Alan
With the WAT910HX / RC you have the makings of sensitive asteroid occultation timing setup.  The addition of a GPS video time inserter, a larger aperture lens and a controllable mount is all that is required in terms of hardware to make useful observations.    A clear sky would be nice too, but we can hope.

Tim

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Joined: 01/04/2020 - 13:13
Video camera

Thanks Tim

Just in the process of setting up but I will be able to do more. We moved house a year back and we are still not straight! Too much going on. There is a 12 inch Newtonian f-8 waiting in the wings to go on my PEM mount, meanwhile it is an EQ5 with small stuff.

We do get a different climate here, so near the coast it is more a maritime climate so here's hoping!

Alan