Tonight – April 26, 2015 – as seen from around the world, the moon and dazzling planet Jupiter pop out close together at evening dusk. Of course, we really mean that these two worlds reside close together on the great dome of sky, not close together in actual space. The moon, our closest celestial neighbor, is roughly 400,000 km (250,000 miles) from Earth this evening. Jupiter lies far beyond the moon, at about 1,900 times the moon’s distance from us.
Also look westward as evening falls, to get an eyeful of the sky’s brightest planet, Venus. Named for the goddess of love and beauty, Venus shines even more brilliantly than Jupiter, the king planet. Venus is also closer of these two worlds, at about one astronomical unit away. In contrast, Jupiter resides some 5.14 astronomical units away.
Planets of the solar system, such as Venus and Jupiter, are always found on or near the ecliptic – Earth’s orbital plane projected onto the constellations of the Zodiac. The ecliptic marks the sun’s path across our sky. Since the other planets in our solar system orbit the sun in nearly the same plane as Earth, you know to look for them along the ecliptic, or sun’s path.
Presently, Venus is in front of the constellation Taurus the Bull, and Jupiter is found in front of the constellation Cancer the Crab.
Both Venus and Jupiter will remain evening planets for several months to come.
Both of these worlds are now traveling eastward in front of the background stars of the Zodiac. Venus and Jupiter are both heading (on our sky’s dome) for Regulus, the brightest star in the constellation Leo the Lion.
Over the next few months watch as swifter-moving Venus edges closer and closer to slow-plodding Jupiter in the evening sky. Venus will catch up with Jupiter on July 1, 2015, to showcase a stunningly close conjunction of the sky’s two brightest planets in late June/early July 2015.
Believe it or not, Venus will actually reach Regulus before Jupiter does.
Venus and the star Regulus will have their conjunction in mid-July 2015, while Jupiter will have its conjunction with Regulus at the end of the first week of August 2015.
Bottom line: The “star” near the waxing moon on April 26, 2015 is really a planet, Jupiter. Starting on this night – and for the next several months – you can watch as the sky’s brightest and second-brightest planets – Venus and Jupiter, respectively – draw closer together. They’ll have a stunningly close conjunction in late June and early July 2015.