Wednesday, July 25, 2018
The Sky This Week - Thursday July 26 to Thursday August 2
The Full Moon is Saturday, July 28. The Moon is at apogee, when it is furthest from the earth, on the 27th. There is a total lunar eclipse on the morning to the 28th, the longest this century.
On the East coast, the eclipse starts when the sky is quite dark at 4:24 am AEST and Totality is at 5:30 pm AEST, so the Moon will appear to be a burnished copper disk in a dark sky full of stars. Totality occurs as the sky is paling and maximum eclipse occurs at civil twilight, so the Moon may be difficult to see against the brightening sky. As this is quite a dark eclipse of 1.6 depth, it may even end up dark grey or brown.
In the central states the eclipse starts before astronomical twilight at 3:54 am ACST and Totality begins at 5:00 am ACST when the sky is still fully dark. Central states will also see the eclipsed Moon in all its coppery glory accompanied by red Mars. The colour contrast will be interesting.
In WA, the eclipse starts with the Moon quite high and all of the eclipse is seen. The eclipse starts at 2:24 am AWST and Totality begins at 3:30 am AWST.
More details, timings for major cities, photography and observing hints are at my eclipse page.
Similar views will be seen throughout Australia at the equivalent local time (60 minutes after sunset, click to embiggen).
Brilliant Venus is now visible in the evening until well after full dark. Venus is visible to the unaided eye from sunset, easy to see 30-60 minutes after sunset and can viewed well after 90 minutes after sunset. During the week Venus moves towards the bright star Spica. Mercury is visible below Venus near the bright star Regulus. This is the last week to see Mercury in the evening before it returns to the morning skies.
This will be the last wekk to see all 5 together in the evening sky until Mercury returns in September.
Similar views will be seen throughout Australia at the equivalent local time (just after 60 minutes after sunset, click to embiggen).
The insets are a simulated telescopic view of Jupiter and its moons at 18:59 ACST, Ganymede has just reapaerd from eclipse and Europa has just entered occultation. Jupiter, Saturn and Mars are shown as seen with a 5mm telescopic eyepiece.
Similar views will be seen throughout Australia 90 minutes after sunset (click to embiggen).
Venus is readily visible above the horizon in the early evening. It is bright enough to be visible from just on sunset and to well past 90 minutes after sunset at full dark, when it is two and a half hand-spans above the horizon. During the week Venus moves towards the bright star Spica.
Mercury sinks lower in the evening skies this week. Mercury is visible below Venus near, Regulus. This is the last week to see Mercury in the evening before it returns to the morning skies.
Jupiter is high the early evening sky. It was at Opposition on the May 9th, and is still visible most of the night. It is a good telescopic object in the mid to late evening and is highest around 19:30 local time. There are some good Jovian Moon events this week. This week Jupiter is still close to the bright star alpha Librae (Zubenelgenubi).
Mars is in Capricornius and is now rising in the evening, although best telescopically in the morning. Mars is rapidly brightening ahead of opposition later this month and is now quite bright (although it will get brighter still) and readily recognisable in the late evening. In a telescope you may see a few features as the huge dust storm sweeping the planet subsides. Mars 1s at opposition on the 27th, when it is biggest and brightest as seen from Earth. This is the best opposition since 2003. A guide to observing Mars at the time is at my Mars Opposition page. The Moon is close to Mars on the 28th. During the Lunar eclipse it will be interesting to to contrast ruddy Mars with the copper Moon.
Saturn is climbing higher the evening sky, and is now a good telescopic object in the mid to late evening sky. It was at opposition, when Saturn is biggest and brightest as seen from Earth, on June the 27th. It is within binocular range of several attractive clusters and nebula. It is close to the bright globular cluster M22 and the pair are visible in binoculars and wide field telescope eyepieces.
Printable PDF maps of the Eastern sky at 10 pm AEST, Western sky at 10 pm AEST. For further details and more information on what's up in the sky, see Southern Skywatch.
Cloud cover predictions can be found at SkippySky.
Here is the near-real time satellite view of the clouds (day and night) http://satview.bom.gov.au/
Labels: weekly sky