Occultations and Transits

Occultations and transits seen by
Kryss Katsiavriades


Occultations

An occultation occurs when one object covers or occults another. The Moon can occult four bright stars: Aldebaran (Taurus), Regulus (Leo), Spica (Virgo) and Antares (Scorpius). These occultations occur at irregular intervals.

The Moon can also occult planets. These occultations are even rarer.

Rarest of all is an occultation of a star by a planet and one planet occulting another.

Occultations Seen

Date
Occulted
Object
Occulted By
Details
Location
2 March 1974 Saturn Moon Took 10s to disappear on Moon's dark edge. Newcastle, UK
5 November 2001 Saturn Moon Full Moon - saw disappearance through binocculars. Muswell Hill, London, UK
23 February 2002 Jupiter Moon Gibbous Moon - saw disappearance behind dark edge through binocculars - it faded slowly for 20s and vanished just before 03:00. Around 04:00 saw setting Moon with Jupiter very close. Highbury, London, UK
16 April 2002 Saturn Moon Crescent Moon. Saw the two close together before and saw appearance through binocculars and telescope (saw Saturn's rings and Moon's craters). Highbury, London, UK
8 December 2022 Mars Moon Full Moon and Mars at opposition. Watched the approach in a clear sky and the actual occultation. Took 40s to disappear. Wood Green, London, UK


Transits

Only the Inferior Planets can transit the Sun. A transit occurs when an Inferior Planet passes directly between the Earth and the Sun appearing as a black spot against the Sun. Transits are rare.

Transits of Mercury occur about 13 times per century; 9 in November and 4 in May. The transit is not visible to the naked eye and must be viewed by projection.

Transits of Venus only occur in June and December. A pair of transits is separated by 8 years but each pair occurs after 105 or 121 years. A transit of Venus can be seen with the naked eye if a filter is used. They are so rare that none occurred in the 20th Century.

Transits Seen

Date
Planet
Details
Location
7 May 2003 Mercury After sunrise - observed it by projection from 07:30 to 11:29 (3rd Contact). Hackney, London, UK
8 June 2004 Venus Observed it by projection, eclipse glasses (naked eye) and through a large telescope from 06:19 to 12:23. Alexandra Palace, London, UK
9 May 2016 Mercury After noon - observed it by projection from 13:10 to 14:10 (cloud). Swiss Cottage, London, UK
11 November 2019 Mercury After noon - observed it through telescopes in park with other astronomers. Regents Park, London, UK

Photographs

Photographs by my oldest friend, Bob Snell, of the transit of Mercury.

Photographs by my friend, Mike Southby, of the transit of Venus.

Photographs by Talaat Qureshi and Nicola Mackin of the transit of Mercury.

Photographs by Lesley Bound, Nicholas Joannou and Tunc Tezel of the transit of Mercury.