Astronomy From Your Back Yard - 5/5 to 5/11 2010
Thursday, May 06 2010 @ 02:42 pm EDT
Contributed by: dgrosvold
Week of May 5th – May 11th
Wednesday night, the Last Quarter Moon will occur at 11:16 PM CDT. Do you know the names of the Moon? “Moon” is a Germanic word, related to the Latin word mensis, which means month. However, the Latin name for the Moon was Luna, from which we get lunar, and lunatic. In Greek mythology, the Moon was known as Selēnē. The modern term selenology is a derivative, and it refers to the study of lunar science, including geology. The Moon is the fifth largest natural satellite in the Solar System, which makes it unique because Earth, the Moon’s host planet, is only about 4 times as large as the Moon. The close Earth-Moon size relationship makes it almost a binary planet system rather than a planet-satellite system such as those found in the large outer planets.
Earth’s sister planet Venus is low in the western sky in early evening, and will be setting by around 10:00 PM CDT. Venus may not be visible if your western horizon is blocked by trees or buildings.
By Dave Grosvold
Yellowish Saturn is high in the southeastern sky in the evening, this week, and will be visible all night. Reddish Mars also rides high in the southern sky in the evening, and will be visible all night as well. The Earth is slowly drawing farther away from both these planets as the year progresses, so they will be slightly dimmer each night as the year wanes. The dimming of these two wanderers would not necessarily be visible from night to night but it is noticeable when compared from month to month.
All this week, The Coma Cluster is visible above Virgo high in the southeastern sky. This is a beautiful open star cluster visible in 7X50 or 10x50 binoculars. Probably the best time for viewing this cluster is between 9:30 and 11:00 PM CDT on Thursday, Friday, or Saturday evenings. Don’t forget to look for galaxies in the Virgo Cluster this week as well. See last week’s post for details on that.
According to most sources, the Eta Aquarid Meteor shower peaks on the morning of Thursday, May 6th. The best time for viewing will be between 3 and 5 AM CDT on the mornings of May 5th, 6th, and 7th. One of two meteor showers composed of dust particles from Halley’s Comet, every year the Eta Aquarids can be seen from as early as April 21 through about May 12. However, the number of meteors you are likely to see will be low until around the time of the peak on May 5/6. At their peak, Northern Hemisphere observers are likely to see about 10 meteors every hour. Unfortunately, since the waning crescent Moon is just past Last Quarter, the Moon will be in the south eastern sky in the early morning hours, and some of the fainter meteors may be rendered invisible due to resulting moonglow.
Look low in the eastern sky in the early morning on Sunday, May 9th for Jupiter rising below the crescent Moon. Also on Sunday morning, you can catch the Galilean Moons (the four largest moons of Jupiter,) in a small telescope or binoculars before dawn between 4:30 and 5:00 AM CDT.
The International Space Station will make another pass low in the northern sky on Tuesday, May 11th. The ISS will rise in the North, becoming visible when it is 10° above the horizon, rise to 14° in the north-northeast, and then sink back to about 10° in the NNE before disappearing again. It will only reach about -0.7 magnitude this time.
There will be several Iridium Flares this week, mostly in the early morning hours, however the brightest will be in the evening on Sunday evening, May 9th. Look for Iridium 83 Sunday evening at 9:16 PM CDT high in the Eastern sky at an altitude of 58°. This flare will reach a brightest magnitude of -8 so it should be an easy catch. Check the web site at Heavens Above for other Iridium Flare times and locations.