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Jupiter Occults UCAC4 341-085052 on 18th of January 2019

On the 18th of January 2019 between approx. 4h30 and 5h UTC Jupiter will occult UCAC4 341-085052. The star is the variable star SY Oph. Area of visibility is the eastern Europe and the eastern mediterranean. The Gaia Gmag of the star is 6.19. Here you can find more.

ESOP XXXVIII in Paris Observatory

The 38th Symposion on Occultation Projects will be held in Paris. Hosting place is Paris Observatory. Paris Observatory is the oldest astronomical observatory with research activities (construction started in 1667), the foremost astronomical observatory of France, and one of the largest astronomical centres in the world.

The scientific meeting will be from Friday 30th of August to Sunday 1st of September 2019. In keeping with ESOP tradition, post conference excursions will be proposed. Have a look!

Call for Observation

(1756 ) Giacobini Occults HIP 7358 in the Morning of 2018 Nov 10
The Brightest Occultation for Germany in 2018!

In the morning hours of November 10th the small minor planet (1756) Giacobini (diameter 10 km) will occult HIP 7358 (6.7 Vmag) for a maximum duration of 1.9 sec. Have a look and observe!


Total Lunar Eclipse ... Shortly before Centrality

One of the most prominent examples of occultations is a lunar eclipse. The longest lunar eclipse of this century takes place just now! The image with a conventional DSLR camera has been taken from Munich. Copyright W. Beisker, IOTA-ES (2018)




Successful observation of the occultation by Himalia of 10m5 star!
Observed from stations in Poland and Ukraine.


Positive chords from the Himalia event are to be reported. Two with the double system Max and Moritz operated by Anna Marciniak (Moritz)) in Poznan and 100km away the other by Eberhard Bredner near Konin (with Max) and a third, very short occultation (~2 sec) observed by Roman Hirsch (Astronomical Observatory Institute) in Borowiec. Also positive observtions in the Ukraine. More news will follow!

Call for Observation >>> Update 17th of May!
Himalia (J-6) Satellite of Jupiter Occults Bright Star (20th of May 2018)!

Himalia, an irregulate satellite of Jupiter will occult a 10mag star on the 20th of May 2018 around 22h 16min UTC for northern and eastern Europe. The occultation track has moved about 180 km north! Read more!


Occultation by minor planet (130) Elektra successfully observed in Europe

Over 30 stations participated in the most successful observation of an occultation by (130) Elektra ever. Never before has the shadow profile of minor planet (130) Elektra been so accurately measured. More than 30 observers from Italy, Switzerland, France, Belgium and Great Britain measured the occultation around 00:30 U.T. on April 21, 2018. Read more!


GRAZPREP-software for 2018
Find and prepare grazing occultations in detail

Grazing Occultations of stars by the moon are local events and thus require an individual selection according to personal observation preferences. The GRAZPREP-software assists in all aspects of finding individually interesting events as well as selecting the best observing stations promising the most contacts between the star and the lunar limb in high resolution. GRAZPREP can be downloaded and installed, including a step by step operation tutorial.
Find more informations about this software package!
Call for Observation

2002TC302 Occults UCAC4-593-005847 (15m8) for Europe. New astrometric update!

On 28th of January 2018, around 21h55min UTC, the TNO 2002TC302 occults a 15m8 star. This is a relatively easy to observe event, because of the low speed of the TNO relative to the star of only about 5km/sec. Give it a try! Even instruments with less than 30 cm diameter should do it. And you don't need a high speed camera for this slow event. With 1 or 2 seconds exposure time you can do valuable science! A new update of the prediction has been issued by J. Desmars. Have a look!.


(8) Flora occults TYC 1341-00957-1 on 2018 Jan 13

A campaign has been set up for this event. Have a look!

Haumea, the most peculiar of Pluto companions, has a ring!

From a press release of the Instituto de Astrofisica de Andalucia (IAA-CSIC)

The trans-neptunian belt contains four dwarf planets, among which Haumea stands out for its extremely elongated shape and rapid rotation.

A stellar occultation revealed the main physical characteristics of this heretofore poorly known body – among which the most surprising presence of a ring. Researchers around Jose-Luis Ortiz and Pablo Santos-Sanz published a paper in Nature, that showed a ring around Haumea. This is the first trans-Neptunian object with a ring.
"One of the most interesting and unexpected findings was the discovery of a ring around Haumea. Until a few years ago we only knew of the existence of rings around the giant planets; then, recently, our team discovered that two small bodies situated between Jupiter and Neptune, belonging to a group called centaurs, have dense rings around them, which came as a big surprise. Now we have discovered that bodies even farther away than the centaurs, bigger and with very different general characteristics, can also have rings,” says Pablo Santos-Sanz, a member of the IAA-CSIC team. Also members of IOTA-ES, professionals and amateurs as well, contributed to this research. It has been published by
J. L. Ortiz et al. "The size, shape, density and ring of the dwarf planet Haumea from a stellar occultation". Nature, (2017) DOI: 10.1038/nature24051

Transcontinental Occultation of a 12m4 star UCAC4 410-143659 by Triton on the 5th/6th of Oct 2017 around 23h50 UTC.
Visible from USA and large parts of Europe

Many stations throughout Europe have recorded the event with telescope of different sizes ranging from 20cm to more than 1 meter diameter. An example of the central flash recorded near the central line in Elvas, Portugal is shown in the following picture. It as been taken with a 27cm telescope and a 12 bit digital CCD camera.
CF of Triton, Elvas Pt
--> A very preliminary lightcurve shows the occultation with the central flash. Exposure time 0.3 seconds. No filter. Copyright W. Beisker, IOTA-ES, 2017

The updates of the predictions of this campaign can be
followed here.

Predictions for 55 TNOs and Centaurs for 2017 and 2018

In the frame of the European-funded Lucky Star project, a webpage with predictions of occultations in 2017 and 2018 for 55 TNOs and Centaurs had been developed by Josselin Desmars from Bruno Sicardy's team. Occultations can be selected by date, magnitude range and name of the occultation object. Have a look!

Minor Planet Occultations of Bright Stars

Occultations by stars brighter than about 9th mag will be presented in this blog.http://call4obs.iota-es.de

Grazing Occultations of Stars by the Moon

A field of professional astronomy between science and beauty
Among all occultation phenomena in the sky grazing occultations of stars by the moon have a very unique character. The observation of these spectacular events ... read the overview in full length!

TU24 movement

Asteroid TU24
recorded from Munich around 1h 10min UT on 30th Jan 2008. Fast motion (5x). Near miss of 11m9 star TYC 4140-520
EU-Project EUROPLANET creates a database for professional and amateur observatories!. Have a look to their questionaire! Read more...

Information about running TNO campaigns

Information about running campaigns for TNO occultations you can find here at Felipe Braga-Ribas website. Follow up the prediction process and get ready to observe if it is in your area!

Inauguration of IOTA-ES 0.5m portable telescope.
It has been named "m2"

On the 8th of October an inauguration party has been held at the Archenhold observatory in Berlin. Members of IOTA-ES including the board of directors celebrated the inauguration with champagne and sausages.
The first real observation with the instrument had been the successful observation of the occultation by Pluto on the 19th of July 2016. It will still take some more time, to finish some minor work and to write the operation instructions. But in the near future it can be booked by IOTA members for observation projects. Read more!!

Successful observation of a Chariklo occultaton in Namibia with the 0.5m portable instrument m2.

On the 9th of April the m2 instrument was used by IOTA-ES member Mike Kretlow as part of an international campaign in cooperation with the EU research project LuckyStar to observe the occultation of UCAC4-294-211208 (14m) by Chariklo in Namibia. Despite poor weather situation, the occultation could be recorded using a Raptor camera with 0.08 sec exposure time. This was the first "Out of Europe" use of m2.

More positive observations came from a IOTA-ES member (Karl-Ludwig Bath) observing at the IAS observatory (Hakos). One more station operated by Jean-Luc Dauvergne was successful too. 3 out of 6 deployed stations got data, the other failed due to unfavorable weather conditions.
A very preliminary lightcurve shows the central body near its maximal diameter and the rings of Chariklo as well.

The XXXVIII European Symposion on Occultation Projects

will be held in Paris at Paris Observatory from the 30th of August to 3rd of September 2019. Informations you can find here.

The Journal for Occultation Astronomy
is now free for all, except the last 2 issues. Get it for free!
Call for Observations!
Occultations of Bright Stars by Minor Planets can be found here .
Reporting lunar occultations
You have to know, how to report lunar occultations! Your reports have to be sent to the email address lunoccult.

Dave Herald reports from Australia how to do it!!!

For Occultwatcher Users
European Feed for Lunar Occultations of Double Stars

A "Lunar Occultations Add-in" for "OccultWatcher" to get interesting lunar occultations of double and suspected double stars. Read more.
How many photons
do you get from a star? Read more...

GPS ... Where am I ?
Positionsbestimmung mit GPS und Karte... in German Read more...
The Artificial Night Sky Brightness
for Occultation Observing Stations in Europe Read more...