Astroblog

The Last Quarter Moon is Wednesday May 7. Jupiter is the brightest object in the early evening sky, and is visited by the crescent Moon on May 4. Mars is prominent in the evening sky. Saturn rises higher in the evening sky. Venus is prominent in the morning sky. The eta Aquariid meteor shower peaks on the morning of the 7-8 May. The asteroids Vesta and Ceres are visible in binoculars.

The Last Quarter Moon is Wednesday May 7.  The Moon is at apogee (furthest from the Earth) on May 6.

Evening sky on Sunday May 4 looking north-west as seen from Adelaide at 20:00 pm ACST in South Australia. Jupiter is above the north-western horizon. The crescent Moon is close by. The inset shows Jupiter's Moons at this time. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Jupiter is in the constellation Gemini and is the brightest object in the early evening sky. Jupiter is becoming harder and harder to observe as it sets earlier.

Jupiter is high enough to begin observing telescopically when twilight ends. Jupiter sets around 21:00, so there is only a couple of hours for good telescopic observation now.

In the early evening it is above the north-western horizon between the bright stars Castor and Pollux, the twins of Gemini, and the bright red star Betelgeuse. Jupiter is quite easy to see as the brightest object in the entire sky, in the evening the sight of bright Jupiter sinking to the west, and bright Mars (still not as bright as Jupiter though) rising in the east is quite beautiful. The crescent Moon is close to Jupiter on Sunday May 4.

Jupiter's Moons are readily visible in binoculars.

Mars  is easily seen in the evening, rising as Jupiter is setting. It is highest in the sky around 22:00. Mars was at opposition, when it is biggest and brightest, on the 9th of April, and is readily distinguishable as the bright red/orange object above the evening horizon. Mars is in the constellation of Virgo near the brightish star Porrima, not far from the bright star Spica (see below). Mars is well worthwhile looking at in a telescope now, although you will need a decent one to see any detail.

Saturn is rising higher in the evening sky, and is at opposition next week. Saturn is high enough around midnight for decent telescopic observation (see below).  Saturn is in Libra near the head of the constellation of the Scorpion. Saturn forms a triangle with the two brightest stars of Libra, its apex pointing towards the head of the Scorpion.

Morning sky on Wednesday May 7 looking east as seen from Adelaide at 5:00 am ACST.  The radiant of the eta Aquariid meteor shower is shown.   Similar views will be seen throughout Australia at equivalent local times. (click to embiggen).

Venus is in the morning sky, above the eastern horizon.  The brightest object in the morning sky, it is now easy to see and although it is past maximum brightness, it will dominate the morning sky for some time to come.

 Venus was at its furthest distance from the Sun on the 23rd of March, and now will begin to slowly sink towards the horizon. Venus  is now a clear  gibbous Moon shape.

Mercury is lost in the twilight.

The eta Aquariids meteor shower, the debris from Halleys comet, peaks on May 6 UT with a ZHR of 55. However, the radiant rises around 2 am, so you can't see the shower until the morning of Tuesday the 7th  in Australia, although good rates will also be seen on the 8th and 9th.

People in the suburbs should see a meteor around once every 6 minutes, and in the country about once every 3 minutes. The radiant of the shower is about five handspans up from the eastern horizon, and three handspans to the left of due east at 4 am, just above and to the left of rising Venus  (see spotter chart at 5 am above).

When looking, be sure to let your eyes adjust for at least 5 minutes so your eyes can be properly adapted to the dark. Don't look directly at the radiant site, because the meteors will often start their "burn" some distance from it, but around a handspan up or to the side. Be patient, although you should see an average of a meteor every six to three minutes, a whole stretch of time can go by without a meteor, then a whole bunch turn up one after the other.


Evening sky on  Saturday May 3 looking east as seen from Adelaide at 20:00 pm ACST in South Australia. Mars is close to the brightish star Porrima. Saturn forms a triangle with the two brightest stars of Libra. The insets show the telescopic views of Saturn and Mars at this time (although you will need a good telescope to see Mars in this detail).

The asteroids Vesta and Ceres are just below Mars, and easily visible in binoculars. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Two bright asteroids are now visible in binoculars in the evening sky. 1 Ceres and 4 Vesta. Vesta  is now bright enough to be just visible to the unaided eye in dark sky locations.Unfortunately the waxing Moon means that it will not be visible to the unaided eye this week. While Vesta is easily seen in binoculars, you will need to watch the same patch of sky in binoculars for a couple of nights to identify it by its movement. Ceres never gets brighter than magnitude 7, but is easily in the range of 10x50 binoculars. See here for a printable black and white map suitable for seeing seeing Vesta and Ceres.

There are lots of interesting things in the sky to view with a telescope. Especially with Jupiter, Mars and Venus so prominent in the sky, and Saturn coming into view.  If you don't have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.

Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pm AEST. For further details and more information on what's up in the sky, see Southern Skywatch.

Labels: weekly sky