Moon with Venus at dawn

In the early morning hours of Thursday, on 9th of November , we will see the Moon at dawn in its narrow crescent phase (4 days after the last quarter) as its bulging illuminated portion faces the bright planet Venus, which appears as a bright "Morning Star" in the autumn and winter sky. Weather permitting, the spectacle doesn't end there, especially for telescope owners. The moon will continue to approach Venus at an angle after sunrise and will obscure the bright planet in the morning. Although this is a daytime sky phenomenon (at a safe distance from the Sun), it could be visible with the naked eye in clear skies, as Venus can be found in bright daylight without binoculars. It is the brighter and easier to see Moon that will help to find it. Of course, the use of a small telescope will multiply the spectacle..

A rare occultation of Venus by the Moon

Why is Venus occulted by the Moon in the first place? Our cosmic counterpart orbits the Earth in an orbit slightly elongated, but also slightly "tilted" towards the main plane of the Solar System, so we more often observe only so-called conjunctions - angular approaches of the Moon to bright planets or stars. But when the Moon happens to be in its orbit just near the plane of Earth's orbit (the so-called ecliptic plane), it can pass directly in front of a planet. It is not necessarily just Venus; all planets orbit the Sun near the ecliptic plane, so each is a "candidate" for occultation by the Moon. But it's a relatively rare phenomenon. Statistically, we can see barely one such occultation of a planet by the Moon from one place on Earth during the year.

When and how to observe?

The whole phenomenon will take more than an hour, but the entry of Venus behind the illuminated lunar edge (visible to the eye) and its exit from behind the unlit edge will take only tens of seconds. Venus will also have a phase - similar to the moon between the full moon and the last quarter, so it will appear as a glowing oval in the telescope. In Opava, the ingress will occur around 11:00am CET, the egress around 12:15pm CET. In other places in the Czech Republic and Slovakia, the times of the phenomenon will vary by tens of minutes. An accurate forecast of the phenomenon for the selected location is available for example on this page or you can simulate the phenomenon for your location using the free downloadable program Stellarium.

Livestream for the public

The Institute of Physics in Opava will offer a live video stream of the phenomenon through the WHOO! "The phenomenon will be imaged between 10:00am and 12:30pm CET with our 45 cm diameter telescope, the recording will be stored in 8k video quality and will also be streamed live in real time on the observatory's streaming channel WHOO! of the Institute of Physics in Opava," adds Daniel Beneš from the Institute of Physics in Opava, who will be handling the transmission.

Contacts:

Bc. Daniel Beneš

RNDr. Tomáš Gráf, Ph.D.

Mgr. Petr Horálek

Bc. Lucie Dospivová

Links and other information: