This is Dudley Observatory’s Skywatch Line for Friday, April 21, through Sunday, April 23, written by Sam Salem.
On Friday, the Sun rises at 6:04am and sets at 7:45pm; the waning crescent Moon rises at 3:30am and sets at 2:16pm. Watch the razor-thin crescent Moon seven degrees below and to the right of Venuson Sunday morning, shorty before sunrise. Spot Venus close to the Moon even after the Sun comes up. Venus, at magnitude –4.7, transitioned from the evening to the morning sky about a month ago,around the time of the spring equinox. In a telescope, Venus looks like a waxing crescent, spanning 45 arc seconds, which is more than 10 times the current apparent diameter of Mars.
Jupiter, at magnitude –2.5, is visible all night long with its four bright moons. Saturn, at magnitude 0.3, rises around 12:30 am, and culminates around 5 am. Mars, at magnitude 1.6, sits low in the west during twilight. On Friday evening, Mars will have its closest approach to the Pleiades cluster in Taurus, low in the west at dusk.
On Saturday night, the Lyrid meteor shower peaks in the predawn hours. This meteor shower has been known to produce exceptionally bright meteors. Under good conditions expect to see as many as 10 to 20 meteors per hour in the few hours before dawn. The crescent moonlight shouldn’t interfere with Lyrid shower. The radiant point of the Lyrid meteor shower is near the bright star Vega in the constellation Lyra, the Harp. Vega rises over the northeast horizon by around mid-evening, moving high overhead just before twilight. The best viewing of this shower is usually during the few hours before morning dawn. The Lyrid meteor shower has the distinction of being among the oldest of known meteor showers. The ancient Chinese are said to have observed the Lyrid meteors “falling like rain” in the year 687 BC. Comet Thatcher is the source of the Lyrid meteors. Every year, in the later part of April, Earth crosses the orbital path of Comet Thatcher (C/1861 G1). The Comet last visited the inner solar system in 1861. It is expected to return in 2276. Meteors are seen when Earthpasses through thick clump of comet rubble. Pieces shed by the comet bombard the Earth’s upper atmosphere at 110,000 miles per hour.
The world celebrates the Earth Day on Saturday. http://www.earthday.org/. This year, Earth Day Network and the March for Science are co-organizing a rally and teach-in on the National Mall in Washington, D.C. Using the teach-in concept deployed for the very first Earth Day in 1970, the rally and teach-in on the National Mall will focus on the vital role science plays in our democracy and the need to preserve this role. More than 1 billion people now participate in Earth Day activities each year, making it the largest civic observance in the world.
The March for Science Albany takes place at New York Capitol Building. Dudley Observatory and miSciwill be participating in the Family science activities. http://www.albany.com/event/march-for-science-144346/.