Starry Night Software
On Sunday, watch for Saturn, Spica and the moon to meet in the morning sky.
updated 2/8/2012 4:58:42 PM ET 2012-02-08T21:58:42

There are two interesting meet-ups in space for skywatchers this week: close encounters between the moon, several planets and stars.

The movements of the sun, moon and planets are all confined to a narrow band of sky known to astronomers as the ecliptic and to astrologers as the zodiac. Almost all of the activities of the major solar system bodies play out among the 13 constellations that mark this band.

You may have thought there are 12 zodiac constellations, but astronomers have long known that a 13th constellation, Ophiuchus, is part of this group. There was a great fuss about a year ago when the astrologers finally caught up and began including Ophiuchans in their fanciful predictions.

Because all this solar system activity is concentrated in a narrow band, there are many close approaches between solar system objects, known to astronomers as conjunctions or appulses.

Two such conjunctions will occur this week, making for some attractive skywatching opportunities. The sky map available with this story shows how the planets will appear together during the cosmic meet-ups.

On Thursday evening just after sunset, look for the brilliance of the planet Venus in the southwestern sky. If you have binoculars or a small telescope, take a closer look.

Just to Venus' left there will be a tiny blue-green speck, a very unusual color for a star. That’s because this is not a star, but the distant planet Uranus, nearly 20 times farther away from the Earth than Venus.

The two planets will be only 20 arc seconds apart, which is about two-thirds of the diameter of the moon. They will easily fit together in the eyepiece of a telescope, and will present an amazing contrast in brightness, size, and color.

Two nights later, just after midnight on Sunday morning, Saturn and the waning gibbous moon will rise in the southeastern sky, with the first magnitude star Spica framed between them.

As the morning progresses, the moon will slip underneath Spica. Its proximity to this bright star makes its rapid eastward movement very obvious.

  1. Space news from
    1. KARE
      Teen's space mission fueled by social media

      Science editor Alan Boyle's blog: "Astronaut Abby" is at the controls of a social-media machine that is launching the 15-year-old from Minnesota to Kazakhstan this month for the liftoff of the International Space Station's next crew.

    2. Buzz Aldrin's vision for journey to Mars
    3. Giant black hole may be cooking up meals
    4. Watch a 'ring of fire' solar eclipse online

While watching these three objects cross the sky, you won't be able to miss bright Mars leading the "parade" one ecliptic constellation ahead in Leo. Once Sirius — the brightest star in the sky — sets around 2:30 a.m. local time, Mars will be the brightest object other than the moon in the sky.

Editor's note: If you have an amazing skywatching photo you'd like to share for a possible story or image gallery, please contact Managing Editor Tariq Malik at

This article was provided to by Starry Night Education, the leader in space science curriculum solutions. Follow Starry Night on Twitter @StarryNightEdu.

© 2013 All rights reserved. More from


Discussion comments


Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments