Observer’s Guide – June 2015
Well it took long enough but Winter finally started. Here where I live, the evenings are finally cold, the air is finally clear, and the stars are back out in their finest, brightest glory. It’s a fantastic time to observe, so here’s a quick rundown on what you can see:
The month starts with the Moon. It passes close by Saturn on the 1st, one day before Full Moon on the 2nd. At this phase, the Moon is so bright that deep sky observing is hardly worth the effort, and you can read a newspaper without artificial lights. Great for romance, terrible for astronomy.
On the 4th, planetary observers will have get to see two of Jupiter’s moons casting their shadows on the jovian surface, in the form of little outer solar system mini-eclipses. Io and Ganymede will begin their performance at 4:54 UT and end it at 6:13 UT. Not ideal for South African viewers, but those in South America will be ideally positions.
On the 5th, Venus reaches greatest Eastern elongation, meaning that it will be at its highest point above the eastern horizon of this particular orbit. If you’re a morning evening (thanks for the correction, John!) observer, there’s no way you’ll miss it
On the 9th, the Moon will be at third quarter, so deep sky viewers will have a few hours of proper darkness between sunset and moonrise.
The following day, on the 10th, Australians in the north-west might be able to catch an asteroid occultation. Asteroid 424 Gratia will be occulting a 6.1 magnitude star in Aquarius. If you live within the shadow of the occultation, I’d definitely make the effort to catch it and record your observation.
The Karoo Star Party and the Free State Star Party both begin on the 12th. South African astronomers will travel from all over to some of the inkiest black skies in the heart of the country for an extended weekend’s shared astronomy. These events both start on Friday the 12th and run through till Tuesday the 16th.
From the 12th to the 14th, Venus will be near the Beehive Cluster (M44), while the theta Ophiuchid meteor shower peaks on the 13th.
On the 15th, the Moon will be in the Hyades, and pass near by both Aldebaran and Mercury. In fact, to observers in the southern Indian Ocean, the Moon will actually occult Mercury, while high arctic observers will catch it occulting Aldebaran.
The Moon will be new on the 16th, for probably the best deep sky observing night of the year (weather permitting!). Meteor spotters should take advantage of the darkness to catch the Lyrids meteor shower when it peaks on this day.
The 20th will bring us an interesting grouping, with the Moon, Jupiter and Venus all appearing within a few degrees of each other. The following day, the 21st, is the June Solstice marking the beginning of astronomical Winter for the southern hemisphere, and Summer for the north.
The Moon then reaches 1st quarter on the 24th. On this same day, Mercury will be at greatest elongation in the morning sky.
And that, apart from the regular motions of the stars and constellations, is that! The winter constellations are busy moving into place with Scorpius and Sagittarius getting higher and highest in the sky, and the Southern Cross culminating shortly after sunset.
All in all, this should be a great month so dress up warmly, get your telescope or binoculars out, and take the opportunity to both catch up on familiar old favourites and try to find something new!