Tonight – March 15, 2012 – Venus appears above Jupiter on our sky’s dome. Both are in front of the constellation Aries the Ram. Only a week ago – on March 8 – Venus was shining below Jupiter. These two worlds have been spectacular for many evenings now!
Venus and Jupiter are both heading upward toward the tiny, dipper-shaped Pleiades star cluster, yet Venus outpaces Jupiter by leaps and bounds. Venus will meet up with the Pleiades in early April 2012, but Jupiter won’t reach this part of the starry sky until June. By then, both Jupiter and the Pleiades will appear very low in the eastern, predawn sky.
We draw in the ecliptic – the pathway of the planets – on our feature sky chart at the top of this page. More accurately, the ecliptic is really a projection of the Earth’s orbital plane onto the stellar sphere. Because the planets orbit the sun on nearly the same plane that Earth does, the ecliptic serves as a handy reference for locating the planets. Without fail, the planets of the solar system always reside on or near the ecliptic.
Where is the ecliptic in relation to the Milky Way?
The ecliptic outlines the center stripe on the great highway of stars known as the zodiac. The constellations of the zodiac have served as a primary reference since time immemorial because it’s in this region of the starry heavens that the sun, moon and stars circle the sky. This year, in fact, the sun will pass in front of the constellation Aries from April 18 to May 13. And on this same date – May 13, 2012 – the sun and Jupiter will be in conjunction near the border of the constellations Aries and Taurus. In other words, on that date, Jupiter will be most directly behind the sun as seen from Earth for this year. We won’t see Jupiter then. It’ll be hidden in the sun’s glare. Afterwards, in June 2012, it’ll reappear low in the east before dawn.
Can you see the Pleiades star cluster and the star Aldebaran in the constellation Taurus tonight? If so, try to picture the ecliptic swinging between these two stellar signposts with the mind’s-eye.
Then watch as Venus leaves Jupiter behind in the constellation Aries, and speeds onward toward the Pleiades star cluster in the constellation Taurus the Bull.source:http://earthsky.org