by Dave Leake
So . . . is anyone into NASCAR racing? Have a favorite driver? There’s a race of sorts going on in the western sky after sunset with the main “drivers“ being Venus, Mars, and Saturn. Each are racing eastward against the starry background along the plane of the solar system, which we called the “ecliptic.“
If you’re a betting person, I’d put my money on Venus. In June, the set time for Venus doesn’t change very much. It hovers right around 11pm CDT, which is pretty late. And around summer solstice time, the Sun set time doesn’t change abruptly either. So it is as if Venus is hanging in sky relative to the horizon as the stars pass behind it. On June 11, Venus makes a straight line with Castor and Pollux near the west-northwestern horizon. At magnitude -4.0, it’s bright! A telescope will show a disk about 75% lit. Three nights later, look for Venus 4-5 deg above a crescent Moon. Venus heads towards Leo later in the month, passing to within a degree of the Beehive Star Cluster (M44) on the 19th and 20th.
Mars has an interesting encounter with the star Regulus this month. Though the star is obviously much farther away, they will appear to come to within a degree of the star on the weekend of June 5th and 6th. Watch as Mars passes the star. On the 16th, Mars, Regulus and the Moon make a nifty triangle in the sky. Mars will appear slightly reddish and a little brighter than Regulus.
Saturn moves the slowest of the three so it’s the turtle of the group. Saturn is 9 deg above the Moon on the 18th. We were looking at Saturn through several telescopes at the last Skywatch and, even with the rings nearly edge-on, looking like a line segment bisecting the planet, it was still impressive! Saturn, Mars and Venus will all get much closer towards the end of July and into early August. So with the Indianapolis 500 upon us, the “big race“ is in the west!
Mercury makes a brief appearance in the morning sky, but it’s nothing to sneeze at. Look early towards the east just before dawn. On the 10th, it rises just after 4:30am, 9 deg below a crescent Moon. Mercury disappears quickly the last week of June and ventures into the evening sky where it will be setting in darkness in mid-July. More on that next month.
Jupiter rises by itself at about 2am early in June, though this time gets earlier as the month goes by until it rises at 12:30am by the end. On the morning of June 6th, Jupiter is 6 deg to the lower right of a lovely crescent Moon in the east-southeast. For those looking for a challenge, the planet Uranus is about a half a degree above and to the left of Jupiter on the morning of the 8th. At magnitude 5.9, you may be able to catch it in binoculars if you can hold them still. Uranus would be a bit fainter than the Galilean moons. And check out the cloud bands, too! You’ve probably heard that one appears to be missing! This is fairly rare but it has happened before.
The magazines report that it is a good time to try to find a dwarf planet this month! The asteroid (and now “dwarf planet“) Ceres reaches opposition on June 18 at magnitude 7.2. However, look early in the month as, on June 1st, Ceres skirts the bottom of the Lagoon Nebula, above the Teapot of Sagittarius. It’s a bit fainter early in the month (magnitude 7.5) but you should still be able to see it. Look on consecutive nights for movement.
The magazines also report a comet in our morning skies. Comet C/2009 R1 (McNaught) was magnitude 17 last September, but it is expected to brighten. This is Mr. McNaught’s 54th comet! That’s impressive! The comet is coming in at a steep angle (71 deg) to the ecliptic. You might be able to see it in binoculars. On May 31 it is below the star Beta Andromedae. By June 6/7 it is 2 deg from Gamma Andromedae. By the 13/14th, it is 3 deg south of Alpha Persei in the northeast. On June 21st, it is expected to be above Capella, very low, but maybe magnitude 6. For more info, look here: http://www.rasnz.org.nz/Comets/2010McNaughtR1.htm. Let’s check it out!
There’s also a lunar eclipse this month . . . .sort of. The eclipse is only partial with the north half of the Moon going into the Earth’s shadow, but the event begins on the morning of June 26 at 5:17am, which is near sunrise. Meaning stargazers might get to see the beginning of the eclipse in the southwest, but then the Moon will set before the eclipse really gets going.
Lastly, the summer solstice is at 6:28am on the morning of June 21st this year. Happy summer!
Moon Phases
Last quarter: June 4, July 4
New: June 12, July 11
1st quarter: June 19, July 18
Full: June 26, July 25
If you would like to see the phases of the moon, past, present, and
future, log on to
http://aa.usno.navy.mil/data/docs/MoonPhase.php