Sunday, March 31, 2013

April 2013 Celestial Highlights


Roanoke Valley's April Sky

Early April - 10:30 p.m.
Late April - 9:30 p.m.


Visible Planets:

MERCURY lost in the bright morning twilight. To the right of the thin crescent Moon at 6:30 a.m. on April 8. 

VENUS lost in the solar glare. Behind the sun on March 28. 

MARS lost in the solar glare. Behind the sun on April 17.

JUPITER high in the west 60 minutes after sunset at the end of March and low in the west-northwest 60 minutes after sunset at the end of April. Next to the Moon on April 14.

SATURN rises in the east at sunset and is high in the south at midnight. Visible all month.  Next to the full Moon on April 25.


Use the Big Dipper to locate:
The North Star
Capella
Pollux and Castor
Leo
Arcturus
Spica

Use Orion to locate:
Aldebaran
Sirius
The Winter Triangle

To use this map:
Face south and hold the map above your head. The stars on the map will match the stars in the sky.


Such is our view from Earth...

Saturday, March 16, 2013

Moon meets Jupiter on March 17


On Sunday March 17, look high in the west  for the moon, just shy of 1st quarter. It glows below the bright planet Jupiter. This provides a juxtaposition of giant, but distant Jupiter against the much smaller — 40 times smaller — and much closer moon. Jupiter lies over 2000 times farther than the moon! All of this results in Jupiter appearing starlike while the moon shows an impressive orb.

If you look at Jupiter through steadily held binoculars, you will see one starlike object slightly above the planet and two, maybe three below it. These are its Galilean moons which sizes are on the same order as of our moon. 

Four moons in one evening!

Such is our view from Earth...

Friday, March 15, 2013

How to find PanSTARRS


Between March 15 and March 18, the best times to spot Comet PanSTARRS are between 8:00 and 8:15 p.m. Any observing location having a relatively unobstructed low western horizon (yes, I know that is hard to find) away from bright lights should work. 

How high above the horizon will it be? Extend your arm and the width of your clinched fist is about 10 degrees. (Yes, taller people have longer arms, but they also have bigger fists, and smaller people have shorter arms and smaller fists. This makes the effective angular size of the clinched fist about the same for people of all heights.) The comet should be about 10 degrees (1 clinched fist) above the 0 degree horizon, and it will be slightly north of due west at 8:10 p.m.

By next Thursday March 21, the comet will likely be dimmer but slightly higher (1-1/4 "fists") in the sky and farther northward along the horizon, maybe 2 "fists" to the left of due west. The best time to see it then would be 8:10 to 8:20.

It is a lot easier to see through binoculars. (The angular field of view of typical binoculars is 5 to 6 degrees.) Remember, clear skies are needed. Haze greatly reduces its visibility.

Such is our view from Earth...



Wednesday, March 13, 2013

Comet PanSTARRS has arrived!

Comet PanSTARRS is not as bright nor as dramatic as recently predicted. It is visible, however, to those Curious Skywatchers who make the effort to spot it. Look directly to the west about forty-five minutes after sunset. Low in the sky sits the comet with its short tail. Because it is just visible to the unaided eye, binoculars greatly aid in the search. As the nights pass, PanSTARRS moves to the northwest rising slightly higher each evening. Since the comet is receding from the sun and the Earth, it fades from view before the end of March.

Such is our view from Earth...