Space Lizard Amateur Astronomy Blog

Why look at just one planet when you can see two? In the coming weeks there will be a pair of close planetary pairings. But  with both showing up in the predawn hours, you’ll have to get up early to see them. The most obvious pairing, easily visible to the naked eye, is Venus and Mars. Just start by finding Venus low in the east, now in the constellation Pisces. At a dazzling magnitude -2.9, it’ll stand out clearly. Slightly lower and to the left will be Mars, shining at magnitude 1.2. As time goes on the pairing will become even better, with the planets appearing higher in the sky, brighter and closer together.   They will reach their closest point on June 21. By then they will be in the constellation Aries and will be shining at magnitudes -3.5 and 1.1 respectively. 

While Venus and Mars are putting on their show, another interesting pairing will be taking place in the constellation Capricorn. But without a telescope, you’ll only see half of this pairing. During the last week of May, Jupiter and Neptune will appear less than a degree apart. With Jupiter at a bright magnitude -2.5, it will stand out clearly in the southeastern sky, along the eastern edge of Capricorn. Look slightly above Jupiter for Neptune. If you’re using a low power eyepiece, they should both be visible in the same field of view. With Neptune at a dim magnitude 7.9, it won’t be the most spectacular pairing. But it’s always interesting when two planets appear so close, and it’s also a good chance to spot a planet that can sometimes be hard to find. The picture at right shows how the pairing would look on the morning of May 20. Star Mu Capricornus, at magnitude 5, will join the pair. The red circle indicates a typical field of view through a low power eyepiece. Although not shown in the picture, Jupiters large moons will add to the show and are always worth a look. So if you’re up early (or very late, as is the case for some of us) don’t miss this pair of planetary pairings.

As last week’s full moon begins to wane, let’s take a look at lunar impact crater Tycho. Named for early Danish astronomer Tycho Brahe, it is often regarded as the finest example of a rayed crater. It’s rays, formed of material ejected by the impact that formed the crater, extend across a significat portion of the lunar surface. Another intereting feature of Tycho crater is it’s central peak, rising roughly 1.6km above the crater floor. As may be guessed from it’s sharply defined appearance, Tycho is a relatively young crater; it’s age estimated at 108 million years. It’s sharp appearance also makes Tycho an easy crater to find. Just look in the moon’s southern highlands, follow the rays back to their center, and it will be obvious which crater is Tycho. Start with low magnification to take in the intricate and beautiful system of rays, then push in with higher magnification for the crater itself. This is one crater worth a second look.