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Monday, December 10, 2018

 

The Sky This Week - Thursday December 13 to Thursday December 20

The First Quarter Moon is Saturday, December 15.  Mars is visible low in the evening skies. The First Quarter Moon is close to Mars on the 15th. Venus is bright in the morning sky with Mercury below. Comet 46P is readily visible in binoculars and in dark sky locations has been seen with the unaided eye. Geminid meteor shower peaks

The First Quarter Moon is Saturday, December 15.

Morning twilight sky on Saturday, December 15 looking east as seen from Adelaide at 5:26 ACDST (30 minutes before sunrise). Venus is bright with Mercury low to the horizon below it. The inset shows the telescopic view of Venus at this time.

Similar views will be seen elsewhere in Australia at the equivalent local time (30 minutes before sunrise)


Evening sky on Saturday, December 15 as seen looking west from Adelaide at 22:12 ACDST (90 minutes after sunset). Mars is close to the First Quarter Moon. The inset shows the telescopic view of Mars at this time.


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


Evening sky on Sunday, December 16 as seen looking north from Adelaide at 22:12 ACDST (90 minutes after sunset).  The location of comet 46P and the variable star Mira is shown. Similar views will be seen elsewhere in Australia at the equivalent local time (and most of the Southern Hemisphere 90 minutes after sunset)). Click to embiggen.


Comet 46P is rapidly brightening and is roughly magnitude 4.5 now, readily seen as a fuzzy blob in binoculars. Is bright enough to (just) see with the unaided eye under dark sky conditions and is brightest this week, between the 13th and the 16th of December. The comet is closest to the Earth on the 16th, but you may wish to wait until the Moon sets on the morning of the 17th to see the comet at its best. More details on how to see it, along with charts suitable for printing, are here.

 Mira (omicron ceti), a star in the constellation of Cetus the whale, is a  red giant that pulsates over a period of about 331 days and changes brightness from below naked eye visibility to a peak of round magnitude 2 (roughly as bright as gamma Crucis in the Southern Cross) in around 330 days. Mira is at past peak magnitude this week, but may stay bright the rest of this month. Following a line drawn between Sirus and Rigel will bring you to Mira.

Geminids as seen from Brisbane facing north at 2:00 am AEST on the morning of Saturday December 15. The Geminid radiant is marked with a starburst. (similar views from elsewhere at equivalent local time eg Sydney 3:00 am AEDST, Adelaide 3:30 am, click to embiggen).

The Geminids are a fairly reliable meteor shower and this will be a good year for them with little moon interference.

The radiant doesn't rise until just before midnight (daylight saving time) in most of Australia, so you will still have to disturb your sleep for this one. The peak is on the morning of Saturday the 15th when  Australians should see a meteor every one to two minutes under dark skies in the early morning of the 15th, between 1:00 am and 4:00 am local time. The further north you are the better the meteor rates. You can find predictions for your local site at the meteor flux estimator (choose 4 Geminids and date 14-15 December, don't forget to change the year to 2018). For more details see my Geminid page.


 Venus climbs higher in the morning skies.

Mercury  is low in the morning twilight.

Jupiter  is returns to the morning sky but is low in the twilight.

Mars is in Capricornius and is readily seen in the evening. Mars is now rapidly dimming and shrinking. When Sirius rises Mars is no longer the brightest object in the night sky aside from the Moon. In a telescope the "gibbous" shape of Mars will be obvious. Mars is close to the First Quarter Moon on the 15th.

Saturn is lost in the twilight..

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/

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Friday, December 07, 2018

 

Southern Skywatch December 2018 edition is now out!

Location of Comet 46 P Wirtanen as seen looking north-east from Adelaide at 22:10 ACDST on Tuesday the 13th of December (90 minutes after sunset), when the comet is closest to the Sun. Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen.

The December edition of Southern Skywatch is now up.

This month Saturn is lost from the evening sky, sky for the first half of the month as Mercury and Jupiter return to the morning sky.

Venus is lost to view in the twilight. Uranus is at opposition on the 24th and is (just) visible to the unaided eye in dark sky locations.  Venus climbs higher in the morning sky,  Jupiter and Mercury are close together in the morning sky on the 22nd.  Mars is is rapidly dimming and is close to Neptune on the 7th.

December 13-21st, comet 46P at its brightest, possibly visible to the unaided eye. Variable star Mira fades. Morning December 15, Geminid meteor shower.

Mercury  is visible in the evening sky this month, meeting Jupiter on the 22nd.

Venus is climbing higher in the morning skies and is close to the crescent Moon on the 4th.  In even small telescopes it is a thin crescent (may also be visible as a crescent in good binoculars).

Jupiter is close to Mercury on the 22nd.

 Mars was at opposition on July the 27th. Mars is close to Neptune on the 7th and the first quarter Moon on the 15th.

Saturn is low in the twilight. December 9 crescent Moon close to Saturn.

December 4, crescent Moon near Venus.

  December 9 Moon close to Saturn. December 15, Moon and Mars close.

December 12, Moon at Apogee; December 24, Moon at Perigee. 

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Mars and Neptune spectacularly close tonight (7 December 2018)

Chart showing the location of Mars and Neptune tonight (Friday 7 December 2018) as seen looking west fro Adelaide at 22:06 ACDST (90 minutes after sunset, Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). The inset shows the simulated telescopic view of Mars and Neptune through a 4" Newtonian Reflector with a 5mm eyepiece. Click to embiggen.

Mars and Neptune will be spectacularly close tonight (Friday 7 December). The pair will be a mere 4 arc minutes apart (that's a fraction of a finger-width), and the pair will easily fit into the field of view of the high power eyepiece.

Mars is readily obvious as the bright red object above the western horizon. Even small telescopes will pick the pair up, with Neptune being the brightest (dim) object close to Mars, but you may need a larger scope to pick up Neptune's bluish hue. You will need large binoculars (10x50 or bigger) and dark skies to see Neptune in binoculars (it is currently magnitude 7.9 so you need to be able to see faint stars of magnitude 8 or dimmer to pick it up).

The pair will be closer tonight than they will come for the next 200 years, so go have a look if you can.

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Thursday, December 06, 2018

 

My First View of Comet 46P Wirtanen (6 December 2018)

My sketch of 46P tonight at 10:57 pm ACDST from suburban Adelaide. Made with 10x50 binocularsSimulation of 10x50 binoculars view of the smae field at the same time in Stellarium.

I finally got to see 46P tonight (after cloud, rain and a range of other issues). Took a while to sort out the star hopping to Azha (eta (η) Eridani, but once that was done comet 46P was readily see as a large fuzzy patch. The sketch is a bit wobbly from trying to juggle sketch pad, binoculars and red light torch, but not too bad after a long break fro sketching.

Hopefully the weather will stay clear and I can get some camera images as well.

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Seeing comet 46P Wirtanen at its brightest from Australia

Location of Comet 46 P Wirtanen as seen looking north-east from Adelaide at 22:10 ACDST on Tuesday the 13th of December (90 minutes after sunset), when the comet is closest to the Sun. Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen.Location of Comet 46 P Wirtanen as seen looking north-east from Adelaide at 22:13 ACDST on Sunday the 16th of December (90 minutes after sunset), when the comet is closest to the Earth. Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen.

Comet 46P is on track to be the brightest comet of this year. Currently magnitude 5.0, it is set to pass pass Earth at 0.0781 AU (~30 time the distance between the earth and Moon), this makes it the 10th closest comet to pass Earth in the modern era.

It is still a bit uncertain how bright it will get but it should get to between magnitude 4 and possibly as bright as  magnitude 3 (about as bright as gamma Crucis, the fifth brightest star in the Southern Cross).

The comet will be brightest between December 13 to December 19. It will be closest to the Sun on the 13th, and closest to Earth on the 16th (just after midnight on the 17th of AEDST). 

However, although potentially bright, its fussy, diffuse nature means it will be difficult to spot with the unaided eye under suburban conditions. Even under dark sky conditions it will be a faint fuzzy dot. Despite breathless statements about it being "as big as the full Moon" the comet is so diffuse you can only see this extended coma with long exposure camera images, not with the eye.

 However, there are already reports of the  comet being visible to the unaided eye under dark sky conditions in Australia, and it is being picked up by simple DSLR cameras. It is readily visible in strong binoculars and small telescopes, but you will need a serious telescope and astronomical camera to pick up any detail, including the faint tail.


Simulated binocular view as seen from Adelaide at 22:06 ACDST on Tuesday the 20th of November (90 minutes after sunset). The view is of the area around star Azha (eta (η) Eridani see charts above and below). Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen. On the 7th the comet will be about the same distance below Azha.

The comet is a reasonably easy target for binoculars, unfortunately the waxing moon will make it harder to spot  during the time when it is brightest.

However, if you wait until Moon set (around midnight on the 13th and 2 am on the 17th (actually, for the east coast on daylight savings time the comet is closest just after midnight), the comet will be reasonably high above the northern sky and in a good position to view.

The comet is now is an area where there are useful guide stars.

Black and white printable spotters chart for locating comet 46P over the coming month as seen from Adelaide at  90 minutes after sunset, (basically a black and white version of the chart at the top). Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen and print.

At the moment the best way to find it is draw an imaginary line between Sirius and Rigel, then continue on until you reach the next brightest star Menkar (α Ceti) that is the constellation of Cetus. Then back off about a hand-span and up two and you will come to the brightish star Azha (eta (η) Eridani) on the 6th the comet is above, and on the 7th below this star.

The comet is moving rapidly as it comes close to the Earth. While it won't "whizz" across the sky it will move substantially night to night.




Black and white printable binocular chart for locating comet 46P between 6- 14 December as seen from Adelaide at 22:06 ACDST  (90 minutes after sunset, basically a black and white version of the chart at the top). The circle is the approximate field of view of 10x50 binoculars. Click to embiggen and print. Use in conjunction with the spotters maps for orientation.Black and white printable binocular chart for locating comet 46P between 13- 21 December as seen from Adelaide at 22:10 ACDST  (90 minutes after sunset, basically a black and white version of the chart at the top). The circle is the approximate field of view of 10x50 binoculars. Click to embiggen and print. Use in conjunction with the spotters maps for orientation.

On the 10th and 11th the comet is within a binocular field of Menkar. On the 13th if you look for the distinctive upside down V shape of the head of Taurus the Bull, then follow the line of stars up from the bright red star Aldebaran you will come to a pair of brightish stars, the comet is just under that. On the 16th the comet is between the distinctive cluster the Pleiades and bright red Aldebaran.

PDF versions of the black and white charts above which are higher quality print are linked below. Spotters chart
Binocular Chart 6-14 Dec
Binocular Chart 13-21 Dec

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Wednesday, December 05, 2018

 

Geminid Meteor Shower 13-15 December 2018

The northern horizon at 4:00 am ACDST as seen from Adelaide on Saturday December 15. 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 3:00 am AEDST as seen from Sydney on Saturday December 15. 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 broke rock fragments from its close approach to the sun.

The Geminids are a fairly reliable meteor shower and this year moonlight will not significantly interfere. Some decent meteors rates should be seen.

Unlike the Leonids, where there is a very narrow peak of high activity, the Geminids have a broad peak and will show good activity well before and after the peak, and on the day before and after. The peak is December 14, 12h 30m UT. That is 23:30 pm AEDST December 14 in Australia.  This is just before the Moon set, and before the radiant is high enough for decent rates, but there will still be very goor rates from around 2-3 am AEDST (1-2 am AEST) on the morning of the 15th in Australia. As the radiant doesn't rise until just before midnight (daylight saving time) in most of Australia, so you will still have to disturb your sleep for this one.

Australians should see a meteor every two to three minutes under dark skies in the early morning of the 15th, between 1:00 am and 4:00 am local daylight saving time. You can find predictions for your local site at the meteor flux estimator (choose 4 Geminids and date 14-15 December, don't forget to change the date to 2018). I have also made a table for major citiess 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.

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) and be patient, it may be several minutes before you are rewarded with you first meteor, then a couple will come along in quick succession (a meteor every three minutes is an average, they won't turn up like a ticking clock but more or less randomly).

Predicted meteor rates for selected towns

TownMorning December 13 Morning December 14Morning December 15
Adelaide8 meteors/hr17 meteors/hr22 meteors/hr
Brisbane10 meteors/hr21 meteors/hr31 meteors/hr
Darwin14 meteors/hr31 meteors/hr40 meteors/hr
Perth10 meteors/hr21 meteors/hr31 meteors/hr
Melbourne7 meteors/hr15 meteors/hr20 meteors/hr
Hobart5 meteors/hr12 meteors/hr16 meteors/hr

Choose a viewing spot where you can see a large swathe of sky without trees or buildings getting in the way, or with street lights getting in your eyes. The darker the spot the better (but do be sensible, don't choose a spot in an insalubrious park for example). While the radiant is where the meteors appear to originate from, most of the meteors will be seen away from the radiant, so don't fixate on the radiant, but keep your eye on a broad swath of sky roughly centred just above the radiant (as the radiant doesn't rise very high, looking exactly at the radiant will mean you miss some higher up).

A lawn chair or something similar will make your observing comfortable (or a picnic rug spread on the ground and a nice pillow), and having a Thermos of hot coffee, tea or chocolate to swig while watching will increase your comfort. Despite it being summer, make sure you have a jumper or something as the night can still get cold

Guides to taking meteor photos are here and here.

As well, Orion and the Hyades will be visible and bright Venus, rises an two and a half hours before sunrise. So it will be a quite nice morning for sky watching. Keep an eye out for satellites!

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/

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Tuesday, December 04, 2018

 

The Sky This Week - Thursday December 6 to Thursday December 13

The New Moon is Friday, December 7.  Saturn and Mars are visible low in the evening skies. The crescent Moon is close to Saturn on the 9th, Venus is bright in the morning sky and is joined by Mercury late in the week. Comet 46P is visible in binoculars. Variable star Mira is bright.  The Geminid meteor shower begins at the end of the week.

The New Moon is Friday, December 7. The Moon is at apogee, when it is furthest from the Earth, on Wednesday the 12th.

Morning twilight sky on Thursday, December 13 looking east as seen from Adelaide at 5:52 ACDST (30 minutes before sunrise). Venus is bright with Mercury low to the horizon below it. The inset shows the telescopic view of Venus at this time.

Similar views will be seen elsewhere in Australia at the equivalent local time (30 minutes before sunrise)


Evening sky on Sunday, December 9 as seen looking west from Adelaide at 21:26 ACDST (60 minutes after sunset). Saturn is just on the horizon near the crescent Moon with  Mars above. The inset shows the telescopic view of Mars at this time.


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


Evening sky on Saturday, December 8 as seen looking north-east from Adelaide at 22:06 ACDST (90 minutes after sunset).  The location of comet 46P and the variable star Mira is shown. Similar views will be seen elsewhere in Australia at the equivalent local time (and most of the Southern Hemisphere 90 minutes after sunset)). Click to embiggen.


Comet 46P is rapidly brightening and is roughly magnitude 5.0 now, readily seen as a fuzzy blob in binoculars. It may become bright enough to (just) see with the unaided eye in late December. More details on how to see it, along with charts suitable for printing, are here.

 Mira (omicron ceti), a star in the constellation of Cetus the whale, is a  red giant that pulsates over a period of about 331 days and changes brightness from below naked eye visibility to a peak of round magnitude 2 (roughly as bright as gamma Crucis in the Southern Cross) in around 330 days. Mira is at peak magnitude this week, and may stay bright the rest of this month. Following a line drawn between Sirus and Rigel will bring you to Mira.
 
Geminids as seen from Brisbane facing north at 2:00 am AEST on the morning of December 14. The Geminid radiant is marked with a starburst. (similar views from elsewhere at equivalent local time eg Sydney 3:00 am AEDST, Adelaide 3:30 am, click to embiggen).

The Geminids are a fairly reliable meteor and this will be a good year for them with little moon interference.

The radiant doesn't rise until just before midnight (daylight saving time) in most of Australia, so you will still have to disturb your sleep for this one. The peak is not until next Saturday when  Australians should see a meteor every one to two minutes under dark skies in the early morning of the 14th, between 1:00 am and 4:00 am local time. However, in the lead up to the peak you should see some decent meteors under dark skies. The further north you are the better the meteor rates. You can find predictions for your local site at the meteor flux estimator (choose 4 Geminids and date 14-15 December, don't forget to change the year to 2018). For more details see my Geminid page.


 Venus has returned to the morning skies.

Mercury  is low in the morning twilight.

Jupiter  is lost in the twilight and will return to the morning sky mid December.

Mars is in Capricornius and is readily seen in the evening. Mars is now rapidly dimming and shrinking. When Sirius rises Mars is no longer the brightest object in the night sky aside from the Moon. In a telescope you may see a few features but viewing will be difficult. This week the "gibbous" shape of Mars will be obvious.

Saturn is low in the north-western evening sky in the early evening and is setting around 10:00 pm. Its closeness to the horizon means it is no longer a good telescopic target. It is close to the crescent Moon on the 9th.

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/

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Tuesday, November 27, 2018

 

The Sky This Week - Thursday November 29 to Thursday December 6

The Last Quarter Moon is Friday, November 31.  Saturn and Mars are visible low in the evening skies. Venus is bright in the morning sky and visited by the Moon on December 4. Comet 46P visible in binoculars. Variable star Mira peaks in brightness.

The Last Quarter Moon is Friday, November 30.

Morning twilight sky on Tuesday, December 4 looking east as seen from Adelaide at 4:50 ACDST (60 minutes before sunrise). Venus and the crescent Moon are close together above the horizon. The inset shows the telescopic view of Venus at this time.

Similar views will be seen elsewhere in Australia at the equivalent local time (60 minutes before sunrise)

Evening sky on Saturday, December 1 as seen looking west from Adelaide at 21:19 ACDST (60 minutes after sunset). Saturn is just on the horizon with  Mars above. The inset shows the telescopic view of Mars at this time.

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






Evening sky on Saturday, December 1 as seen looking east from Adelaide at 21:57 ACDST (90 minutes after sunset).  The location of comet 46P and the variable star Mira is shown. Similar views will be seen elsewhere in Australia at the equivalent local time (and most of the Southern Hemisphere 90 minutes after sunset)). Click to embiggen.


Comet 46P is rapidly brightening and is roughly magnitude 5.5 now, readily seen as a fuzzy blob in binoculars. It may become bright enough to (just) see with the unaided eye in late December. More details on how to see it, along with charts suitable for printing, are here.

 Mira (omicron ceti), a star in the constellation of Cetus the whale, is a  red giant that pulsates over a period of about 331 days and changes brightness from below naked eye visibility to a peak of round magnitude 2 (roughly as bright as gamma Crucis in the Southern Cross) in around 330 days. Mira will peak magnitude later this week, and may stay bright the rest of this month. Following a line drawn between Sirus and Rigel will bring you to Mira.


 Venus has returned to the morning skies and is close to the crescent Moon on December 4..

Mercury  is lost in the twilight .

Jupiter  is lost in the twilight and will return to the morning sky mid December.

Mars is in Capricornius and is readily seen in the evening. Mars is now rapidly dimming and shrinking. When Sirius rises Mars is no longer the brightest object in the night sky aside from the Moon. In a telescope you may see a few features but viewing will be difficult. This week the "gibbous" shape of Mars will be obvious.

Saturn is low in the north-western evening sky in the early evening and is setting around 10:15 pm. Its closeness to the horizon means it is no longer a good telescopic target.

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/

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Tuesday, November 20, 2018

 

The Sky This Week - Thursday November 22 to Thursday November 29

The Full Moon is Friday, November 23.  Mercury is lost in the twilight. Saturn and Mars are visible low in the evening skies. Venus is bright in the morning sky. Comet 46P visible in binoculars.

The Full Moon is Friday, November 23.   The Moon is at perigee, when it is closest to Earth, on the 26th.

Morning twilight sky on Saturday, November 34 looking east as seen from Adelaide at 4:54 ACDST (60 minutes before sunrise). Venus and the bright that Spica  are close together above the horizon. The inset shows the telescopic view of Venus at this time.

Similar views will be seen elsewhere in Australia at the equivalent local time (60 minutes before sunrise)



Evening sky on Saturday, November 24 as seen looking west from Adelaide at 21:49 ACDST (90 minutes after sunset). Saturn is just on the horizon with  Mars above. The inset shows the telescopic view of Mars at this time..

Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset, click to embiggen).






Evening sky on Saturday, November 24 as seen looking east from Adelaide at 21:49 ACDST (90 minutes after sunset).  The location of comet 46P is shown. Similar views will be seen elsewhere in Australia at the equivalent local time (and most of the Southern Hemisphere 90 minutes after sunset)). Click to embiggen.


Comet 46P is rapidly brightening and is roughly magnitude 6.0 now, readily seen as a fuzzy blob in binoculars. It may become bright enough to (just) see with the unaided eye in December. More details on how to see it, along with charts suitable for printing, are here.

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.


 Venus has returned to the morning skies and is close to the bright star Spica.

Mercury  is lost in the twilight by mid week.

Jupiter  is lost in the twilight and will return to the morning sky next month.

Mars is in Capricornius and is readily seen in the evening. Mars is now rapidly dimming and shrinking. When sirius rises it is no longer the brightest object in the night sky aside from the Moon. In a telescope you may see a few features but viewing will be difficult.

Saturn is low in the north-western evening sky in the early evening and is setting around 10:45 pm. Its closeness to the horizon means it is no longer a good telescopic target.

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/

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Seeing comet 46P Wirtanen from Australia

Location of Comet 46 P Wirtanen as seen from Adelaide at 21:42 ACDST on Tuesday the 20th of November (90 minutes after sunset). Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen.

46P is a short period comet which ahas an orbital peiod of 5.4 years. This year is a particularly favourable year and the comet may become as bright as magnitude 3 (about as bright as gamma Crucis, the fifth brightest star in the Southern Cross)

The comet will pass at 0.0781 AU (~30 LD) from Earth, on 16 December 2018 making this the brightest close approach for the next 20 years.The comets magnitude might peak as bright as magnitude 3 near its December 16, 2018 closest approach.

However, although potentially bright, its fussy, diffuse nature means it will be difficult to spot with the unaided eye under suburban conditions. Even under dark sky conditions it will be a faint fuzzy dot.  

Simulated binocular view as seen from Adelaide at 21:42 ACDST on Tuesday the 20th of November (90 minutes after sunset). The view is of the area around stars nu (ν) Fornacis and mu (μ) Fornaci (see below). Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen.

The comet is currently around magnitude 6, and a reasonably easy target for binoculars, unfortunately the waxing moon will make it harder to spot for the next week or so.

Also unfortunately it is in an area pretty much devoid of useful guide stars.

Black and white printable spotters chart for locating comet 46P over the coming month as seen from Adelaide at 21:42 ACDST  (90 minutes after sunset, basically a black and white version of the chart at the top). Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset). Click to embiggen and print.

At the moment the best way to find it is draw an imaginary line between Rigel and Achernar, then draw a line perpendicular to this and continue on until you reach the boxy shape that is the constellation of Cetus. then around halfway
between the box and the imaginary line between Rigel and Achernar is the comet, not far from upsilon Ceti.

Black and white printable binocular chart for locating comet 46P over the coming month as seen from Adelaide at 21:42 ACDST  (90 minutes after sunset, basically a black and white version of the chart at the top). The circle is the approximate field of view of 10x50 binoculars.

Within a binocular distance of Upsion Ceti are the two dimmer stars nu (ν) Fornacis and mu (μ) Fornaci. The comet will form a shallow triangle with them becoming a steeper triangle over the following days. 

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