The Sky This Week - Thursday April 25 to Thursday May 2

The Full Moon is Friday April 26. There is a partial eclipse of the Moon on the morning of the 26th, and an occultation in the evening. Jupiter is low in the early evening sky. Saturn is at opposition on the 28th, when it is biggest and brightest as seen from Earth. Mercury is low in the morning skies. Comet C/2012 F6 Lemmon is high in the morning skies.

Western horizon as seen from Adelaide at 5:30 am ACST on April 26. The Moon is near mid-eclipse at this time. The illustration makes it look worse than it will be, there will be a definite dark “chip” seen at the Moon’s south pole, and the southern half of the Moon will be subtly darker than the North.

On the early morning of 26 April there there be a partial eclipse of the Moon. This is a very poor eclipse, with only a small bite take out of the Moon’s northern edge. It is still worth getting up for though.

WA has the best view, while the east coast sees the eclipse in various stages of twilight, and may be quite difficult to see.

The eclipse starts at  5:52 am AEST (nautical twilight twilight), 5:22 am ACST and 3:52 am AWST.

Mid-eclipse is 6:07 am AEST (deep in twilight), 5:37 am ACST and 4:07 am AWST.

See here for a map and contact timings in UT for sites outside Australia

Sky on Friday April 26 looking east as seen from Adelaide at 21:00 local time in South Australia. The left inset shows a telescopic view of Saturn at this time. The right inset shows alpha Librae reappearing from occultation at 20:30. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

The Full Moon is Friday April 26.

The waning Moon passes in front of the bright star Alpha Librae (which rejoices in the name Zubenelgenubi) in the constellation of the Libra the balance on the early evening of April 26. Alpha Librae is a double star with both stars visible to the unaided eye (magnitude 3 and 5 components). The times shown in the table in the link below are for the bright component of the double star, but the 5th magnitude star disappears and reappears 5 minutes earlier.  Timings of the disappearance and reappearance of the stars can be found here.

Saturn is now easily visible above the eastern horizon before midnight in the constellation of Libra. Saturn climbs higher in the evening sky during the week, becoming easier to see.

Opposition (when Saturn is biggest and brightest as seen from Earth) is on April 28, Saturn is a worthwhile evening target for telescopes of any size. The sight of this ringed world is always amazing.

Morning sky on Sunday April 28 looking east as seen from Adelaide at 5:45 am local time in South Australia showing Mercury, Uranus and comet Lemmon. The inset shows a binocular view of Mercury and Uranus at this time. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Mercury  is still prominent low in the morning skies this week, although it is sinking towards the horizon. It is now difficult to see low above the eastern twilight sky 3/4 of an hour before dawn.

Comet C/2012 F6 Lemmon is in the morning skies above Mercury. At around magnitude 6, you will need binoculars to see it clearly. The comet progressively moves higher and becomes dimmer as the week passes.

Bright white Venus  is lost in the twilight.

Mars is lost in the twilight.

Evening sky looking west as seen from Adelaide at 18:30 pm local time on Saturday April 27. The inset shows Jupiter’s Moons at this time. Similar views will be seen elsewhere at the equivalent local times indicated here.  Click to embiggen.

Jupiter is visible low in the early evening, and is the brightest object in the early evening sky.

Jupiter is  low in the western early evening sky, being quite visible in the twilight.  Jupiter is moving away from the Hyades, but is still near the red star Aldebaran.

Jupiter, Aldebaran and the red star Betelgeuse in Orion form a long triangle in the sky. With the Pleiades cluster and the constellation of Orion close by, this is a beautiful sight.

Jupiter is setting progressively earlier, by 7:50 pm local time, so the giant world is harder to see in a telescope. Jupiters’ Moons are easily seen in binoculars, and can be followed from night to night changing position, but with a narrow window between twilight and Jupiter setting, you won’t have time to see much action..

There are lots of interesting things in the sky to view with a telescope. Especially with Saturn so prominent in the sky.  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. Especially during the school holidays.

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

Cloud cover predictions can be found at SkippySky.