Astroblog

The Moon looking east at 04:53 am ACDST in Adelaide on Saturday 1 January, 2022 before Mars disappears behind the Moon. The Moon and Mars are below the bright star Aldebaran (click to embiggen).	The Moon looking east at 05:26 am AEDST in Melbourne on Saturday 1 January, 2022 before Mars disappears behind the Moon.The Moon and Mars are below the bright star Aldebaran (click to embiggen).
Close up view of the start of the occulation at the same time	Close up view of the start of the occulation at the same time

The occultation of Mars will seen in south eastern and south central Australia in the early morning on New Years Day. It will be visible from Adelaide, Hobart, Melbourne and Canberra. Sydney sees a graze 12 minutes before sunrise. The occultation will be low to the horizon with the thin crescent Moon covering Mars. In Adelaide this is after astronomical twilight and in the east with the best views, for Hobart, Melbourne and Canberra this is around nautical twilight.Egress of Mars from behind the Moonis close to Sunrise for the eastern states, so care is needed if young binoculars or telescopes. .

Place	Disappears bright Limb	Reappears dark Limb
Adelaide ACDST	04:53	05:37
Canberra AEDST	05:31	05:47
Hobart AEST	05:30	06:11
Melbourne AEST	05:26	06:00
Sydney AEST	5:36	-

More cities in Australia can be found at the IOTA site (UT times only, which is why is says DEC 31).

Labels: binocular, Mars, Occultation, telescope

The New Moon is Monday, January 3.  Occultation of Mars, morning January 1. Three bright planets are seen forming a line in the early evening twilight. These are Mercury, Saturn and Jupiter. The thin crescent Moon is between Mercury and Saturn on the 4th and between Saturn and Jupiter on the 5th. Then the crescent moon is then close to Jupiter on the 6th. Comet C/2021 A1 Leonard is visible in binoculars but fading.

The New Moon is Monday, January 3. The Moon is at Perigee, when it is closest to the Earth, on January 2.

 

Morning sky on January 1 looking east as seen from Adelaide at 4:53 ACDST (60 minutes before sunrise). Mars is low in the twilight below the bright red star Antares and the Moon is just about to pass in front of Mars. Details for other sites are below.

 Similar views will be seen from South-eastern Australia at the equivalent local time (60 minutes before sunrise, click to embiggen).

 

Evening sky on January 4 looking west as seen from Adelaide at 21:38 ACDST (60 minutes after sunset).  The thin crescent Moon is between mercury and Saturn. Mercury forms a line with Saturn and Jupiter.

 

 

Similar views will be seen throughout Australia at the equivalent local time (60 minutes after sunset, click to embiggen). 

 

Whole sky showing the Jupiter, and comet C/2021 A1 Leonard, January 1, 22:18 ACDST, 90 minutes after sunset (click to embiggen). Orion, Taurus and the Pleiades can be seen above the eastern horizon.

 

 

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

 

Comet C/2021 A1 Leonard as seen looking west
from Adelaide at January 1, 22:18 ACDST, 90 minutes after sunset (click to embiggen). The inset shows the approxinmate binoclar view of the comet at this time. Similar views will be seen in elsewhere in Australia 90 minutes after sunset.

Comet C/2021 A1 (Leonard) is is a nice little binocular object. It is currently in outburst and has even been reported to be (just) visible to the unaided eye. Whether it will remain bright is uncertain.

Mercury  climbs higher in the evening twilight and forms a line with Saturn and Jupiter. The thin crescent Moon is between Mercury and Saturn on the 4th

Venus is lost in the twilight.

Labels: weekly sky

The Last Quarter Moon is Monday, December 27.  Four bright planets are seen forming a line in the early evening twilight. These are Mercury, Venus, Saturn and Jupiter. Venus is rapidly lowering in the sky heading towards Mercury. Mercury and Venus are parallel to the horizon on the 27th and closest on the 29th. Comet C/2021 A1 Leonard may be visible to the unaided eye and is clearly visible in binoculars. Mars is occulted by the Moon on the morning of 1 January 2022.

The Last Quarter Moon is Monday, December 27. 

 Morning sky on December 30 looking east as seen from Adelaide at 4:58 ACDST (60 minutes before sunrise). Mars is low in the twilight below the bright red star Antares with the Moon not far away.  On January 1 the Moon occults Mars as seen from south east Australia. The inset shows the Moon and Mars at 4:53 ACDST as the Moon is just about to pass in front of Mars. Details for other sites are below.

 Similar views will be seen throughout Australia at the equivalent local time (60 minutes before sunrise, click to embiggen).

Evening twilight sky on December 27 looking west as seen from Adelaide at 21:01 ACDST (30 minutes after sunset).  Venus and Mercury are parallel to the horizon and Venus forms a line with Saturn and Jupiter.

 

The insets shows the telescopic views of Venus, and Mercury at this time. Venus is a very thin crescent now. Similar views will be seen throughout Australia at the equivalent local time (30 minutes after sunset, click to embiggen). 

Whole sky showing the Jupiter, Saturn and comet C/2021 A1 Leonard, December 25, 22:18 ACDST, 90 minutes after sunset (click to embiggen). Orion, Taurus and the Pleiades can be seen above the eastern horizon.

 

 

Elsewhere in Australia will see a similar planetary line up that the equivalent time (90 minutes after sunset). 

Comet C/2021 A1 Leonard as seen looking west
from Adelaide at 21:37 ACDST (60 minutes after sunset) on 25 December (Christmas day). Similar views will be seen in elsewhere in Australia 60 minutes after sunset.

Comet C/2021 A1 (Leonard) is this years “Christmas comet”. While not as spectacular as the “searchlight comet” Comet C/2011 W3 Lovejoy, it isa nice little binocular object. It is currently in outburst and has even been reported to be (just) visible to the unaided eye. 

As it climbs higher we will get better views but it will fade rapidly, however, it should be easily visible in binoculars on Christmas day (unless it spectacularly disintegrates). More details and printable black and white charts here.

Mercury  climbs higher in the evening twilight.

Venus is visible in the early evening twilight.  I have been able to see Venus from just after sunset and it is easily seen over 2 hours after sunset, longer if you have a clear western horizon.  Venus forms a line with Saturn and Jupiter. It is now a distinct crescent in even small telescopes. Venus is now heading rapidly towards the horizon.

Labels: weekly sky

Comet C/2021 A1 Leonard as seen looking west from Adelaide at 21:35 ACDST (60 minutes after sunset) on Tuesday 21 December. Similar views will be seen in elsewhere in Australia 60 minutes after sunset (click to embiggen).	Approximate binocular view of Comet C/2021 A1 Leonard as seen looking west from Adelaide at 21:35 ACDST (60 minutes after sunset) shown at daily intervals from 21 to 23 December. The guide stars omega Capricornii, Psi Capricornii and Gamma Microscopium are shown (see the printable charts). Similar views will be seen in elsewhere in Australia 60 minutes after sunset.

 

Comet C/2021 A1 (Leonard) is in outburst (the image to the left I took on the 20th, 9 x15 second 80 ASA canon IXUS, stacked in deep sky stacker). 

Various reports have ranged from Magnitude 2 (easily visible to the unaided eye, to nearly magnitude 4 (difficult to see in the twilight). I was unable to see it with the unaided last night but it was very clear and obviously brighter in binoculars and picked up in photographic images.

How long it will remain in outburst is uncertain, but as it climbs higher in the sky it will be easier to observe as the background sky becomes darker. But definitely go out and look if you can tonight (21 December) around 60 minutes after sunset. Binoculars are a must even if it is unaided eye visible. 

You will need to let your eyes dark adapt to get the best view of the comet, and there is a relatively narrow window between nautical twilight (60 minutes after sunset) , when you have the best chance of picking it up, until it becomes too low to the horizon and is obscured by horizon murk (about half an hour).

On the 21st the comet is around 2 binocular fields south of Saturn,  sweeping south (left) and a bit up from Saturn brings you to the pair of brightish stars, Omega and Psi Capriconii,  left again by one and a half binocular fields from Psi Capriconii is the comet,neat a dimmish star. 

On the 22nd sweeping left from omega Capriconii  will bring you to the comet, just above a dimmish star.

On the 23rd sweeping left and up from omega Capriconii will bring you to the comet, forming a shallow triangle with the stars alpha and gamma Microscopium .

Black and white chart suitable for use with binoculars (you can click to embiggen and print this out, or download and print the PDF files below). 

Use the spotters mas to guide yuo and star hop from Saturn to Omega and Psi Capriconii, then on to the comet. 

A black and white spotters chart suitable for printing is here . A B&W chart suitable for binoculars from the 21st to 25th is available here , the large circle is the approximate field of view of 10x50 binoculars. 

 

 

Labels: binocular, C/2021 A1, comet, unaided eye

Venus 25/9/21 8" Newtonian, 2x Barlow, ToUCam at 640x480 resolution , 113 frames staked in Registax.	Venus 10/10/21 8" Newtonian, 2x Barlow, ToUCam at 640x480 resolution , 113 frames staked in Registax.
Venus 7/11/21 8" Newtonian, 2x Barlow, ToUCam at 640x480 resolution , 101 frames staked in Registax.	Venus 9/12/21 8" Newtonian, 2x Barlow, ToUCam at 640x480 resolution , 100 frames staked in Registax.

My 2021 Phases of Venus campaign has been somewhat disrupted, but I have still managed to capture so decent shots of the increasing size and increasing crescent phase of Venus. Still trying to optimize the gain, shutter speed for the best contrast, not tp mention focus, but not shabby despite my fluffing about.

Labels: astrophotography, telescope, Venus

The Full Moon is Sunday, December 19.  This is an apogee, or "mini" Moon. The earth is at Solstice on the 22nd. Three bright planets are seen forming a line in the early evening sky. Venus forms a line with Saturn and Jupiter  in the western evening sky. Venus is rapidly lowering in the sky. Late in the week Mercury joins the lineup low in the twilight. Comet C/2021 A1 Leonard may be visible from the 16th.

The Full Moon is Sunday, December 19.  This is an apogee, or "mini" Moon, with apogee occurring on the 18th. The earth is at Solstice on the 22nd, when the day is longest.

 Morning sky on December 18 looking east as seen from Adelaide at 4:51 ACDST (60 minutes before sunrise). Mars is low in the twilight, you may need binoculars to see Mars clearly.  

 

 

Similar views will be seen throughout Australia at the equivalent local time (60 minutes before sunrise, click to embiggen). 

 

 Evening sky on December 18 looking west as seen from Adelaide at 20:57 ACDST (30 minutes after sunset).  Venus forms a line with Saturn and Jupiter.

 

 The insets shows the telescopic views of Venus, Saturn and Jupiter at this time. Venus is a distinct crescent now. Similar views will be seen throughout Australia at the equivalent local time (30 minutes after sunset, click to embiggen). 

Whole sky showing the Moon, Jupiter, Saturn and Venus in a line , December 18, 21:34 ACDST, 60 minutes after sunset (click to embiggen). Orion, Taurus and the Pleiades can be seen above the eastern horizon.

 

 

Elsewhere in Australia will see a similar planetary line up that the equivalent time (60 minutes after sunset). 

Comet C/2021 A1 Leonard as seen looking west from Adelaide at 21:34 ACDST (60 minutes after sunset) daily from 18 December. Similar views will be seen in elsewhere in Australia 60 minutes after sunset.

Comet C/2021 A1 (Leonard) is this years “Christmas comet”. While not as spectacular as the “searchlight comet” Comet C/2011 W3 Lovejoy, it will be a nice little binocular object. It is predicted to reach magnitude 4 at its brightest but it will be too close to the sun to see, the earliest we can expect to see it in the southern hemisphere is around the 16th, low in the twilight. As it climbs higher we will get better views but it will fade rapidly. More details and printable black and white charts here.

Mercury  returns to the evening twilight.

Venus is visible in the early evening when the sky is fully dark.  I have been able to see Venus from just after sunset and it is easily seen over 2 hours after sunset, longer if you have a clear western horizon.  Venus forms a line with Saturn and Jupiter. It is now a distinct crescent in even small telescopes. venus is now heading rapidly towards the horizon.

Labels: weekly sky

 Comet C/2021 A1 Leonard as seen looking west from Adelaide at 21:53 ACDST (60 minutes after sunset) shown at daily intervals from 18 to 25 December. Similar views will be seen in elsewhere in Australia 60 minutes after sunset.

Comet C/2021 A1 (Leonard) is this years “Christmas comet”. While not as spectacular as the “searchlight comet” Comet C/2011 W3 Lovejoy, it will be a nice little binocular object. 

It is predicted to reach magnitude 4 at its brightest but it will be too close to the sun to see. Tonight, 12 December 2021, the comet will be at its closest to Earth,  0.233 AU (34.9 million km). However,  the earliest we can expect to see it in the southern hemisphere is around the 16th, low in the twilight. As it climbs higher we will get better views but it will fade rapidly. 

On the 18th it is about 1 and half a binocular fields south from Venus, the on the 21st it is around 2 binocular fields south of Saturn, on the 25th it will be around unaided eye threshold some distance from Saturn and Jupiter. It will be fuzzy dot to the unaided eye and a small tail may be seen in binoculars.

Black an white chart suitable for use with binoculars (you can click to embiggen and print this out, or download and print the PDF files below. 

Unfortunately there are no prominent guide stars to help find it.  While Venus and Saturn are obvious they are approximate guides, there are a few distinctive asterisms closer, but you will need binoculars to see them. 

A black and white spotters chart suitable for printing is here . A B&W chart suitable for binoculars is available here , the large circle is the approximate field of view of 10x50 binoculars. 

On the 16th the comet forms a diamond with Pi, Omicron and Xi Sagittarii, low on the horizon,  on the 18th the comet is around 1 and half a binocular fields south from Venus below a kite shaped group of stars (Omega, 60, 59 and 62 Sagittarii). By the 23rd-25th the comet is amongst the faint stars of the constellation microscopium.

 

 

Labels: C/2021 A1, comet, unaided eye

The First Quarter Moon is Saturday, December 11.  Three bright planets are seen forming a line in the early evening sky. Venus forms a line with Saturn and Jupiter  in the western evening sky with Jupiter dominating once Venus has set. The crescent Moon has been climbing the ladder of planets and is closest to Jupiter on the 9th. Geminid meteor shower peaks morning 14 December. Comet C/2021 A1 Leonard may be visible on the 16th.

The First Quarter Moon is Saturday, December 11. 

Morning sky on December 11 looking east as seen from Adelaide at 5:10 ACDST (45 minutes before sunrise). Mars is low in the twilight, you may need binoculars to see Mars clearly.  

 

 

Similar views will be seen throughout Australia at the equivalent local time (45 minutes before sunrise, click to embiggen).

 

Evening sky on December 9 looking west as seen from Adelaide at 22:07 ACDST (90 minutes after sunset).  Venus forms a line with Saturn and Jupiter. The waxing Moon is within binocular range of Jupiter

 

 The insets shows the telescopic views of Venus, Saturn and Jupiter at this time. Venus is a distinct crescent now. Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset, click to embiggen). 

Whole sky showing the Moon, Jupiter, Saturn and Venus in a line , December 11, 22:07 ACDST, 90 minutes after sunset (click to embiggen). Orion, Taurus and the Pleiades can be seen above the eastern horizon.

 

 

  Elsewhere in Australia will see a similar planetary line up that the equivalent time (90 minutes after sunset).  

Geminid radiant seen facing north from Brisbane at 2:00 am AEST, December 14.The radiant is marked with a starburst (click to embiggen).

The Geminids are a fairly reliable meteor shower, with rates of about a meteor per minute at their best. This is a good year for Geminids, as the waxing Moon sets before the best rates.. 

The radiant doesn't rise until just before midnight (daylight saving time) in most of Australia, so you will have to disturb your sleep for this one. At 1.00 am in the morning AEDST (midnight, AEST) Castor (alpha Geminorum) is about two hand-spans above the horizon and 10 hand-spans to the left of due north. Pollux, the other twin, is less than a hand-span to the left again. The radiant is just below Castor. 

The Geminids have a broad peak and will normally show good activity well before and after the peak, and on the day before and after. Australians should see a meteor every 2-3 minutes under dark skies in the early morning of the 14th, between 2:00 am and 4:00 am. for more details see my Geminid 2021 page.

Comet C/2021 A1 Leonard as seen looking west from Adelaide at 21:32 ACDST (60 minutes after sunset) on 16 December. Similar views will be seen in elsewhere in Australia 60 minutes after sunset.

Comet C/2021 A1 (Leonard) is this years “Christmas comet”. While not as spectacular as the “searchlight comet” Comet C/2011 W3 Lovejoy, it will be a nice little binocular object. It is predicted to reach magnitude 4 at its brightest but it will be too close to the sun to see, the earliest we can expect to see it in the southern hemisphere is around the 16th, low in the twilight. As it climbs higher we will get better views but it will fade rapidly.

Mercury  is lost in the twilight.

Venus is visible in the early evening when the sky is fully dark.  I have been able to see Venus from just after sunset and it is easily seen over 3 hours after sunset, longer if you have a clear western horizon.  Venus is at its greatest brilliance, forming a line with Saturn and Jupiter. It is now a distinct crescent in even small telescopes.

Labels: weekly sky

The northern horizon at 3:00 am ACDST as seen from Adelaide on Tuesday December 14 when the Geminid radiant is highest. The Geminid radiant is marked with a starburst. Similar views will be seen elsewhere in Australia at  a similar latitude and the equivalent local time. (click to embiggen).	The northern horizon at 2:00 am AEST as seen from Brisbane on Tuesday December 14 when the Geminid radiant is highest. The Geminid radiant is marked with a starburst. Similar views will be seen elsewhere in Australia at  a similar latitude and the equivalent local time. (click to embiggen).

The Geminids are unusual meteor shower in that their parent body is 3200 Phaethon, an asteroid, rather than a comet. It is speculated though that Phaeton is actually a "gassed out" comet, and so the debris that makes up the Geminids may still be cometary particles, but is more likely broken rock fragments from its close approach to the sun.

The Geminids are usually a fairly reliable meteor shower and with the waxing Moon setting before the radiant is at its highest rates should be very good.

The Geminids have a broad peak and will show good activity well before and after the peak on the day before and after. The peak is December 14, 07h UT. That is 18:00 am AEDST December 14 in Australia.  Despite the peak being during daylight hours, the best viewing will be from around 3-4 am AEDST (2-3 am AEST) on the morning of the 14th in Australia. As the radiant doesn't rise until just before midnight (daylight saving time) in most of Australia, and the Moon doesn't set until around 2:00 am you will still have to disturb your sleep for this one.

Northern Australians should see a meteor every 2 to 3  minutes under dark skies in the early morning of the 14th between 1:00 am and 4:00 am local time. Obviously under suburban skies you will see fewer.

It is best to wait until moon set before watching so the meteors will not be washed out.

You can find predictions for your local site at the meteor flux estimator (choose 4 Geminids and date 13-14 December, don't forget to change the date to 2021). You will have to enter your local latitude and longitude for your site. I have also made a table for major cities below.

Unfortunately, both Chrome and Firefox have changed their security settings to prevent plugins from running, and the flux estimator only runs under Internet Explorer now.
You can follow the progress of the shower at the IMO Geminids Live page.

At 1.00 am in the morning AEDST (midnight, AEST) Castor (alpha Geminorum) is about two hand-spans above the horizon and 10 hand-spans to the right of due north. Pollux, the other twin, is less than a hand-span to the right again. The radiant is just below Pollux. The best rates is when the radiant is highest,when it is due north, distinctive Castor and Pollux will be your guide still.

When you get up, allow at least 5 minutes for your eyes to adjust and become dark adapted (even if you have stumbled out of bed in the dark, here's some hints on dark adaption of your eyes so you can see meteors better). 

Labels: geminids, Meteors, unaided eye