Astroblog: August 2024

The New Moon is Tuesday, September 3. Venus climbs higher in the evening twilight, the thin crescent Moon is very close to Venus on September 5. Saturn is rising in the twilight, and is a decent telescopic object in the late evening. Mars and Jupiter continue to draw apart as Mars passes between the tips the horns of Taurus the Bull. The crescent Moon forms a line with Aldebaran, Jupiter and Mars on August 29.

The New Moon is Tuesday, September 3.

Western evening sky on Thursday, September 5 as seen from Adelaide at 18:55 ACST (60 minutes after sunset, click to embiggen).

Venus is readily visible now and is now visible when the sky is fully dark.The crescent Moon is very close to Venus. The inset is the binocular view of the pair at the time. The pair will also be visible in low power telescope eye pieces.

Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes after sunset).

The eastern sky at 19:20 ACST Saturday, August 31 (90 minutes after sunset) with Saturn now reasonably high above the horizon. It is still best for telescopic viewing in the late evening.

The inset shows the telescopic view at the time. (click to embiggen).

Similar views will be seen from the rest of Australia at the equivalent local time (90 minutes after sunset).

Morning sky on Thursday, August 29 as seen from Adelaide at 05:44 ACST (60 minutes before sunrise), Mars and Jupiter are close below the red star Aldebaran. The crescent Moon forms a line with Aldebaran, Jupiter and Mars.

The inset is the telescope view of the Jupiter at this time.

Similar views will be seen from the rest of Australia at roughly the equivalent local time (60 minutes before sunrise).

Whole sky on Saturday, August 31 as seen from Adelaide at 19:20 ACST, 90 minutes after sunset (click to embiggen).

Saturn is just peeking over the eastern horizon as Venus sets on the western horizon. Scorpius is moving off the zenith with the heart of the milky way now at the zenith. The Southern Cross is still prominent low in the Southern sky. Between the bright star Canopus and the Southern Cross are a wealth of binocular objects to discover.

Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset).

Mercury is lost in the twilight.

Venus climbs higher in the evening twilight and is readily visible in the evening twilight. The crescent Moon is close to Venus on September 5.

Mars is rising in the morning sky and near Jupiter. The pair continue to draw apart as Mars passes between the tips the horns of Taurus the Bull. The crescent Moon forms a line with Aldebaran, Jupiter and Mars on August 29.

Jupiter is rising in the the morning twilight sky. Jupiter is below the red star Aldebaran.

Saturn climbs higher in the late evening sky.

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.

Star Map via Virtual sky. Use your mouse to scroll around and press 8 when your pointer is in the map to set to the current time.

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

# posted by Ian Musgrave @ 11:25 pm 0 comments

The Last Quarter Moon is Monday, August 26. Venus climbs higher in the evening twilight. Saturn enters the evening sky around 7:00 pm, and is now a decent telescopic object in the late evening. Mars and Jupiter continue to draw apart as Mars passes between the tips the horns of Taurus the Bull. On the 27th the waning moon forms line with Jupiter and Mars and on the 28th the waning Moon forms a triangle with the pair.

The Last Quarter Moon is Monday, August 26.

Western evening sky on Saturday, August 24 as seen from Adelaide at 18:46 ACST (60 minutes after sunset, click to embiggen).

Venus is readily visible now and climbing higher in the twilight.

Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes after sunset).

The eastern sky at 22:00 ACST Saturday, August 24 with Saturn now reasonably high above the horizon for viewing.

The inset shows the telescopic view at the time. (click to embiggen).

Similar views will be seen from the rest of Australia at the equivalent local time.

Morning sky on Wednesday, August 28 as seen from Adelaide at 05:48 ACST (60 minutes before sunrise), Mars and Jupiter are close below the red star Aldebaran. The Moon form a triangle with the pair and is close to the bright star Elnath.

The inset is the telescope view of the Jupiter at this time.

Similar views will be seen from the rest of Australia at roughly the equivalent local time (60 minutes before sunrise).

Whole sky on Saturday, August 24 as seen from Adelaide at 19:11 ACST, 90 minutes after sunset (click to embiggen).

Scorpius is at the zenith with the heart of the milky way below it. The Southern Cross is still prominent in the Southern sky. Between the bright star Canopus and the Southern Cross are a wealth of binocular objects to discover. Saturn is just peeking over the horizon.

Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset).

Mercury is lost in the twilight.

Venus climbs higher in the evening twilight and is readily visible in the evening twilight.

Mars is rising in the morning sky and near Jupiter. The pair continue to draw apart as Mars passes between the tips the horns of Taurus the Bull. On the 27th the waning moon forms line with Jupiter and Mars and on the 28th the waning Moon forms a triangle with them.

Jupiter is rising in the the morning twilight sky. Jupiter is below the red star Aldebaran. On the 27th the waning moon forms line with Jupiter and Mars and on the 28th the waning Moon forms a triangle with them.

Saturn climbs higher in the late evening sky.

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.

Star Map via Virtual sky. Use your mouse to scroll around and press 8 when your pointer is in the map to set to the current time.

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

# posted by Ian Musgrave @ 12:01 am 0 comments


Sky chart facing north on Saturday, August 17 as seen from Adelaide at 19:11 ACST (90 minutes after sunset, click to embiggen). The location of T CrB is shown with a circle. Similar views will be seen 90 minutes after Sunset elsewhere in Australia.	Sky chart facing north on Saturday, August 17 as seen from Adelaide at 19:11 ACST (90 minutes after sunset, click to embiggen). Constellation names and lines are shown for clarity.


My image of Corona Borealis taken on 10 August with my Samsung S24 in astrophography mode at 5x zoom. Stars down to magnitude 7.5 are visible. The approximate location of T CrB is shown with a star above Ɛ CrB.	AAVSO chart of Corona Borealis showing the magnitude of surrounding stars. The decimal points have been omitted eg 22 is 2.2, 89 is 8.9

If you look to the North at astronomical twilight (90 minutes after sunset), you will see a prominent bright orange star, Arcturus (see top chart), if you look downwards and to the right you will see a dainty circlet of stars. Corona Borealis, the northern crown.

While pretty in its own right, it houses a most unusual star, T Coronae borealis (T CrB), also known as the blaze star. T CrB is a recurrent nova, a binary system where gas from a red giant star accretes on a white dwarf companion. Eventually the gas builds up to a density where a nuclear explosion occurs and this is seen as a nova.

A recurrent nova is one where there is a (semi) regular patter of repeated outbursts. T CrB seems to erupt every 80 years, with the last in 1946. Recent patterns of brightening and dimming look like the pre outburst phase of the 1946 eruption, and it is predicted that T CrB may go nova between now and the end of September this year.

When that happens, T CrB will rapidly rise to from its current magnitude 10 (well below eye or binocular visibility) around magnitude 2 about the same brightness as Alphecca, 𝛂 Coronae Borealis (see bottom left-hand panel), the brightest star in the constellation. It will only remain above unaided eye visibility for a week or so.

T CrB is located on the right-hand side to the circlet, just above Ɛ CrB (see bottom left-hand panel) where the line of stars turn down, there are no other bright stars in the region, so when it erupts it will be easily visible.

The challenge:

Take an image of Corona Borealis every clear night during Ausgust-September awaiting the eruption. You will need a stack of ~ 10 images at high ISO of around 1 second duration, then stacked in appropriate software to pick up the faint stars. It would be best if you zoomed in so that Corona Borealis occupies most of the camera field (with a bit of space on the right-hand side so you don’t miss out on T CrB. That way hopefully you will catch not only the eruption, but the fade as well, doing a bit of backyard astrophysics.

Be patient, after a few night astrophotography you will become familiar with the stars and will easily see when T CrB erupts.

You can also follow the T CRB Nova watch on Space weather (in the the righthand panel). Currently magnitude 19.

Labels: astrophotography, citizen science, nova, T CrB

# posted by Ian Musgrave @ 9:44 pm 0 comments

The Full Moon is Tuesday, August 20. Mercury is lost in the twilight.Venus climbs higher in the evening twilight. Saturn enters the evening sky around 8:00 pm, and is now a decent telescopic object in the late evening. The Moon is close to Saturn on the 21st. Mars and Jupiter start the week spectacularly close on the 15th, and then draw apart but remain close for the rest of the week.

The Full Moon is Tuesday, August 20. the Moon is at perigee, when it is closest the Earth, on the 21st.

Western evening sky on Saturday, August 17 as seen from Adelaide at 18:42 ACST (60 minutes after sunset, click to embiggen).

Mercury is no longer visible. Venus is readily visible now and climbing higher in the twilight.

Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes after sunset).

The eastern sky at 22:00 ACST Wednesday, August 21 with Saturn now reasonably high above the horizon for viewing. Saturn is near the just past full Moon.

The inset shows the telescopic view at the time. (click to embiggen).

Similar views will be seen from the rest of Australia at the equivalent local time.

Morning sky on Thursday, August 15 as seen from Adelaide at 06:00 ACST (60 minutes before sunrise), Mars and Jupiter are spectacularly close below the red star Aldebaran.

The inset is the low power telescope view of the pair at this time.

Similar views will be seen from the rest of Australia at roughly the equivalent local time (60 minutes before sunrise).

Whole sky on Saturday, August 17 as seen from Adelaide at 19:11 ACST, 90 minutes after sunset (click to embiggen).

Scorpius is at the zenith with the heart of the milky way below it. The Southern Cross is still prominent in the Southern sky. Between the bright star Canopus and the Southern Cross are a wealth of binocular objects to discover. The fainter clusters will will be hard to see as the Moon is full.

Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset).

Mercury is lost in the twilight.

Venus climbs higher in the evening twilight and is readily visible in the evening twilight.

Mars is rising in the morning sky and starts the week spectacularly close to Jupiter on the 15th.Then the pair separate.

Jupiter is rising in the the morning twilight sky. Jupiter is below the red star Aldebaran and is spectacularly close to Mars on the 15th.

Saturn climbs higher in the late evening sky and the Moon is close to Saturn on the 21st.

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.

Star Map via Virtual sky. Use your mouse to scroll around and press 8 when your pointer is in the map to set to the current time.

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

# posted by Ian Musgrave @ 11:51 pm 0 comments

The First Quarter Moon is Tuesday, August 13. The Moon is close to the bright star Spica in the 10th. Mercury is rapidly fading in the evening twilight, below Venus, as Venus climbs higher in the evening twilight. Saturn enters the evening sky around 8:00 pm, and is now a decent telescopic object in the late evening. Mars comes closer to Jupiter over the week and the pair are spectacularly close on the 15th.

The First Quarter Moon is Tuesday, August 13. the Moon is at apogee, when it is furthest from the Earth, on the 9th.

Western evening sky on Saturday, August 10 as seen from Adelaide at 18:37ACST (60 minutes after sunset, click to embiggen).

Mercury is fading and is low at Nautical twilight an hour after sunset. This is the last week it will be visible as it disappears into the twilight. Venus is readily visible now and climbing higher in the twilight. The waxing Moon is close to the bright star Spica.

Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes after sunset).

The eastern sky at 22:00 ACST Saturday, August 10 with Saturn now reasonably high above the horizon for viewing.

The inset shows the telescopic view at the time. (click to embiggen).

Similar views will be seen from the rest of Australia at the equivalent local time.

Morning sky on Thursday, August 15 as seen from Adelaide at 06:00 ACST (60 minutes before sunrise), Mars and Jupiter are spectacularly close below the red star Aldebaran.

The inset is the low power telescope view of the pair at this time.

Similar views will be seen from the rest of Australia at roughly the equivalent local time (60 minutes before sunrise).

Whole sky on Saturday, August 10 as seen from Adelaide at 19:07 ACST, 90 minutes after sunset (click to embiggen).

Scorpius is nearly at the zenith with the heart of the milky way below it. The Southern Cross is still prominent in the Southern sky. Between the bright star Canopus and the Southern Cross are a wealth of binocular objects to discover. The fainter clusters will now fade as the Moon starts to wax.

Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset).

Mercury rapidly dims in the evening twilight, and will soon be lost to view.

Venus climbs higher in the evening twilight and is readily visible in the early evening twilight.

Mars is rising in the morning sky this week it comes closer to Jupiter and is spectacularly close on the 15th.

Jupiter is rising in the the morning twilight sky. Jupiter is below the red star Aldebaran and is spectacularly close to Mars on the 15th.

Saturn climbs higher in the late evening sky.

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.

Star Map via Virtual sky. Use your mouse to scroll around and press 8 when your pointer is in the map to set to the current time.

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

# posted by Ian Musgrave @ 10:36 pm 0 comments