International Occultation Timing Association
European Section










European Observation Report

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.

Currently, 28 measured chords from successful observers cover the shadow profile. Eric Frappa ( determined from the obtained data an elliptical profile of the minor planet with a size of 261 x 160 km. The chords are well distributed over the entire profile, only at the Eastern and Western edge there are wider gaps. These successful measurements will also provide a highly accurate astrometric position of (130) Elektra, which will bi included in future orbit calculations for this minor planet. More positive observation reports are expected.

In addition to measuring the profile of Elektra, the observation stations have also been watch out for a brief stellar occultation through one of the two moons of (130) Elektra. However, an occultation by these celestial bodies could not be proven so far.

The path prediction was calculated by Steve Preston (IOTA) on February 27, 2018. Compared to his prediction, there was only a small path shift of the real path to the East. The occultation took place about 4 seconds later than predicted.

This is the twelfth occultation by (130) Elektra that has been observed worldwide. The most successful observation so far took place in February 2010. British observers had measured eight chords. Again, an elliptical profile was the result (256 x 155 km).

The next occultation by (130) Elektra is already on 2018 May 01. After its shadow has passed the south of Africa, it will cover Liberia and Sierra Leone. After crossing the Atlantic, the shadow leaves the Earth in the East of the U.S.A.. For observers there, the occultation will take place at an elevation of 12 degrees or less above the horizon only.

Links (check for latest updates):

List of observers (Eric Frappa,

Profile of (130) Elektra (Eric Frappa,

Upcoming Occultation by (130) Elektra on 2018 May 01

Profile of (130) Elektra with DAMIT-Model

Oliver Klös
IOTA/ES, Public Relations