This is the Dudley Observatory Skywatch Line for Wednesday, October 28th and Thursday, October 29th written by Louis Suarato
The Moon is one day past full Wednesday. The 97% illuminated, waning gibbous Moon rises at 6:50 p.m. in the constellation Taurus. Look for the Pleiades star cluster to the Moon’s upper left. The Pleiades, also known as the Seven Sisters, and M45, is comprised of hot blue stars approximately 100 million years old. These highly luminous stars cause nebulosity as they reflect off the dust in the interstellar medium, the area in space between stars. At a distance of 444.2 light-years, the Pleiades is one of the nearest star clusters to Earth, and was first seen through a telescope by Galileo in 1610. Galileo sketched the star cluster, sighting 36 stars. The bright stars of the Pleiades travel close to the ecliptic, and are occasionally occulted by the Moon. The next Pleiades/Moon occultation will take place in 2023.
Thursday night, as the Moon rises, look for Taurus’ brightest star, Aldebaran, approximately one degree to the Moon’s upper right. The Moon will occult Aldebaran as viewed from other parts of the world, but not from our region. The two will be close enough to view in the same field of view of some binoculars and small telescopes. Aldebaran, also known as Alpha Tauri, is an orange giant star, about 65 light-years from Earth. Aldebaran, meaning “The Follower” in Arabic, shines at magnitude .85. On nights when the Moon is not so bright and close, look for two open cluster to the left of Aldebaran. The closest, NGC 1647, is about 3 degrees away and NGC 1746, is about 10 degrees to the north.
The dawn close triumvirate of planets continues with Venus now below Jupiter and above Mars. By 6 a.m., the three planets are over 25 degrees high the pre-dawn sky, and are within an area of 5 degrees or each other. A clear view of the eastern horizon around 6:30 will reveal Mercury rising far below the other planets.