Tuesday, December 31, 2013
The Sky This Week - Thursday January 2 to Thursday January 9
The First Quarter Moon is Wednesday January 8.
Jupiter is visible
in the evening sky. Mars is prominent in the early morning. Saturn rises higher in the morning sky. Earth at Perihelion on the 4th.
The First Quarter Moon is Wednesday January 8. The Earth is at perihelion (when it is closest to the Sun) on the 4th.
Evening sky on Saturday January 4 looking north-east as seen from Adelaide at 22:00 pm ACDST
in South Australia. The inset shows the view of Jupiter through a
telescope at this time. Similar views will be seen elsewhere at the equivalent local time
(click to embiggen).
Jupiter is in the constellation Gemini.
Jupiter rises around 20:30 pm local daylight saving time, while reasonably high enough to observe telescopically in the late evening, it is still best for telescopes in the early morning.
In the morning it is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars.
Venus is lost in the twilight.
Morning sky on Sunday January 5 looking east as seen from Adelaide at 5:00 am ACDST in
South Australia. Mars is high above the horizon, Saturn is lower to
the horizon. Similar views will be seen elsewhere at the equivalent local time (click
to embiggen).
Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Saturn is visible above the eastern horizon before dawn.
Mercury is lost in the twilight.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
The First Quarter Moon is Wednesday January 8. The Earth is at perihelion (when it is closest to the Sun) on the 4th.
Jupiter is in the constellation Gemini.
Jupiter rises around 20:30 pm local daylight saving time, while reasonably high enough to observe telescopically in the late evening, it is still best for telescopes in the early morning.
In the morning it is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars.
Venus is lost in the twilight.
Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Saturn is visible above the eastern horizon before dawn.
Mercury is lost in the twilight.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
Labels: weekly sky
Tuesday, December 24, 2013
The Sky This Week - Thursday December 26 to Thursday January 2
The New Moon is Wednesday January 1. Mars is prominent in the early morning. Saturn rises higher in the morning sky. The Moon is close to Saturn on December the 29th.
Venus is visible low in the western evening sky and is close to the crescent Moon on the 2nd. Jupiter is visible in the evening sky.
The Last Quarter Moon is Wednesday December 25. The Moon is at perigee on the January 2.
Evening sky
looking west as seen from Adelaide at 21:00 pm ACDST on Saturday
December 21. Venus is the early evening sky. The inset shows the telescopic view of Venus.
Similar views will be seen elsewhere at the equivalent local times.
Click to embiggen.
Venus falls further into the evening twilight. This will be the last week to see this fleet world before it disappears into the twilight. However, for most of the week it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until late twilight.
The brightest (spectacularly so) object above the western horizon it is still visible up to an hour after sunset at the beginning of the week (depending on how flat your western horizon is) when the sky is fully dark. Venus is continuing to sink to the horizon, and this will be the last week to see it before it disappears into the twilight. On the 2nd Venus and the Moon are close together, but you will need a flat level horizon (like the sea) to see them shortly after sunset.
Venus is a distinct, wire thin crescent moon shape in even small telescopes and even binoculars now.
Evening sky on Saturday December 28 looking north-east as seen from Adelaide at 22:00 pm ACDST
in South Australia. The inset shows the view of Jupiter through a
telescope at this time. The Moon is close to Jupiter. Similar views will be seen elsewhere at the equivalent local time
(click to embiggen).
Jupiter is in the constellation Gemini.
Jupiter rises around 9:00 pm local daylight saving time, but is still best for telescopes in the early morning. In the morning it is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars.
Morning sky on Sunday December 29 looking east as seen from Adelaide at 5:00 am ACDST in
South Australia. Mars is high above the horizon, Saturn is low above
the horizon. The waning Moon is close to Saturn.
Similar views will be seen elsewhere at the equivalent local time (click
to embiggen).
Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
There are lots of interesting things in the sky to view with a telescope. 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
The Last Quarter Moon is Wednesday December 25. The Moon is at perigee on the January 2.
Evening sky
looking west as seen from Adelaide at 21:00 pm ACDST on Saturday
December 21. Venus is the early evening sky. The inset shows the telescopic view of Venus.
Similar views will be seen elsewhere at the equivalent local times.
Click to embiggen.Venus falls further into the evening twilight. This will be the last week to see this fleet world before it disappears into the twilight. However, for most of the week it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until late twilight.
The brightest (spectacularly so) object above the western horizon it is still visible up to an hour after sunset at the beginning of the week (depending on how flat your western horizon is) when the sky is fully dark. Venus is continuing to sink to the horizon, and this will be the last week to see it before it disappears into the twilight. On the 2nd Venus and the Moon are close together, but you will need a flat level horizon (like the sea) to see them shortly after sunset.
Venus is a distinct, wire thin crescent moon shape in even small telescopes and even binoculars now.
Jupiter is in the constellation Gemini.
Jupiter rises around 9:00 pm local daylight saving time, but is still best for telescopes in the early morning. In the morning it is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars.
Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
There are lots of interesting things in the sky to view with a telescope. 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
Labels: weekly sky
Friday, December 20, 2013
Christmas perambulations
Tuesday, December 17, 2013
Guess What Arrived Today?
Nova Centauri 2013 (V1369 Cen) is Fading
 |  |
| V1369 Nova Centauri 2013 just above beta Centauri at 4:45 am ACDST 17 December . Stack of 10 images taken using a Canon IXUS, ASA 400, 10 second each exposure. Images registered and stacked with DeepSkyStacker, the converted to RGB and contrast adjusted in ImageJ. Click to embiggen to actually see the nova | V1369 Nova Centauri 2013 just above beta Centauri at 4:05 am ACDST 15 December . Stack of 10 images taken using a Canon IXUS, ASA 400, 10 second each exposure. Images registered and stacked with DeepSkyStacker, the converted to RGB and contrast adjusted in ImageJ. Click to embiggen to actually see the nova |
Current lightcurve for V1369 Nova Centauri 2013 from the AAVSO. click to embigen.Just two days after Nova Centauri 2013 became the brightest nova seen in our skies since 1999, it has crashed in brightness to around magnitude 5.
Whetehre we will see another outburst is uncertain, however, with the nearly full Moon in the sky the nova is now very difficult to see without binouclars.
Labels: nova, unaided eye
The Sky This Week - Thursday December 19 to Thursday December 26
Summer Solstice is on December 22. The Last Quarter Moon is Wednesday December 25. Mars is prominent in the early morning, the Moon is close to Mars on the 26th. Saturn rises higher in the morning sky.
Venus is easily visible in the western evening sky. Jupiter is visible in the evening sky now, the Moon is close to Jupiter on the 19th. The bright Nova near Beta Centauri is still visible with the unaided eye.
The Last Quarter Moon is Wednesday December 25. The Moon is at apogee on the 20th.
Evening sky
looking west as seen from Adelaide at 21:00 pm ACDST on Saturday
December 21. Venus is the early evening sky. The inset shows the telescopic view of Venus.
Similar views will be seen elsewhere at the equivalent local times.
Click to embiggen.
Venus is even deeper in the evening twilight. However, it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until the early evening.
The brightest (spectacularly so) object above the western horizon it is still visible up to two hours or more after sunset (depending on how flat your western horizon is) when the sky is fully dark. Venus is continuing to sink to the horizon, but will be spectacular for the next couple of weeks.
Venus is in the constellation of Sagittarius, although it will be hard to see the stars in the twilight. Venus is a distinct, wire thin crescent moon shape in even small telescopes. This week Venus rapidly heads for the horizon as it becomes larger and thinner.
Evening sky on
Thursday December 19 looking north as seen from Adelaide at 22:00 pm ACDST
in South Australia. The inset shows the view of Jupiter through a
telescope at this time. The Moon is close to Jupiter. Similar views will be seen elsewhere at the equivalent local time
(click to embiggen).
Jupiter is in the constellation Gemini.
Jupiter rises around 10:00 pm local daylight saving time, but is still best for telescopes in the early morning. In the morning it is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars. Jupiter is close to the Moon on the 19th.
Morning sky on Thursday December 26 looking east as seen from Adelaide at 5:00 am ACDST in
South Australia. Mars is high above the horizon, Saturn is low above
the horizon. The waning Moon is close to Mars.
Similar views will be seen elsewhere at the equivalent local time (click
to embiggen).
Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight. It is visited by the waning Moon on the 26th.
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
Location of Nova
Centauri 2013 as seen looking north from Adelaide at 3:00 am ACDST
local time.The location is marked with a square. Similar views
will be seen at the equivalent local time in other Southern Hemisphere
locations. Click to embiggen.
V1369 Centauri, Nova Centauri 2013 near beta Centaur is still bright enough (magnitude 4.5 as I type, and fading rapidly) to be seen faintly with the unaided eye, and very easily in binoculars. It has undergone fading and substantial brightening, making it one of the brightest nova known, and will be of interest to follow in the coming days. Unfortunately, you have to wait until early morning for the nova to be heigh enough for a good look.
More detailed spotters charts and instructions are here.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
The Last Quarter Moon is Wednesday December 25. The Moon is at apogee on the 20th.
Venus is even deeper in the evening twilight. However, it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until the early evening.
The brightest (spectacularly so) object above the western horizon it is still visible up to two hours or more after sunset (depending on how flat your western horizon is) when the sky is fully dark. Venus is continuing to sink to the horizon, but will be spectacular for the next couple of weeks.
Venus is in the constellation of Sagittarius, although it will be hard to see the stars in the twilight. Venus is a distinct, wire thin crescent moon shape in even small telescopes. This week Venus rapidly heads for the horizon as it becomes larger and thinner.
Jupiter is in the constellation Gemini.
Jupiter rises around 10:00 pm local daylight saving time, but is still best for telescopes in the early morning. In the morning it is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars. Jupiter is close to the Moon on the 19th.
Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight. It is visited by the waning Moon on the 26th.
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
V1369 Centauri, Nova Centauri 2013 near beta Centaur is still bright enough (magnitude 4.5 as I type, and fading rapidly) to be seen faintly with the unaided eye, and very easily in binoculars. It has undergone fading and substantial brightening, making it one of the brightest nova known, and will be of interest to follow in the coming days. Unfortunately, you have to wait until early morning for the nova to be heigh enough for a good look.
More detailed spotters charts and instructions are here.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
Labels: weekly sky
Sunday, December 15, 2013
My Geminid Meteors, 15 December 2013
This time when I got up for the Geminids at 3:00am the skies were brilliantly clear. Unfortunately the Moon was also higher than yesterday, making the sky bright for the first half of my observing. My limiting magnitude was 4.5 before Moonset (3:36 am) and 5.5 after. I looked basically North, using Jupiter as my reference, sweeping east and west from there, encompassing an area from Orion ,through Canis Major to Leo.
Between 3:00 am - 4:45 am ACDST I saw 9 Geminids (with 3 nice fireballs, one that zoomed below the sickle of Leo and the other shooting towards Taurus), 3 sporadic meteors and 5 satellites. Two satellites were close as they zoomed through Orion (one was likely ISIS 1), and another two crossed paths between Sirius and Procyon
Nova Centari was bright, at least 3.5.
Below is the breakdown of my observing, in 15 minute segments, from 4-4:15 I was also imaging Nova Centauri 2013, so I was not as effective watching for meteors as in the other time periods.
The 6 meteors seen between 3:07-4:00 is consistent with the predicted numbers for my site (6.4) from the meteor flux estimator.
With the radiant 21 degrees above the horizon at my location, a limiting magnitude of 5 (averaging before and after Moonset), and something like 80% of my field of view unobstructed, I come up with a ZHR of 67 in the hour between 16:30 UT and 17:30 UT, which is consistent with the reported ZHR of 64 for 16:47 UT.
This is also consistent with the reports I have seen from South Australia (14-15 meteors in darker sky sites than mine). Other Australia sites were plagued by cloud.
In the northern hemisphere, where the radiant is higher,
a lot more meteors were seen. There was a peak of 200 meteors per hour (ZHR), which was in excess of the predicted 120 meteors per hour predicted, this was when the radiant was below the horizon in Australia. There also seems to be a sub peak at 20:22 UT (that is daylight in Australia, sadly).
All in all, not a bad Geminids, not as good from an Australian perspective as other years, and not as good as this years Aquariids, but not bad none the less.
Between 3:00 am - 4:45 am ACDST I saw 9 Geminids (with 3 nice fireballs, one that zoomed below the sickle of Leo and the other shooting towards Taurus), 3 sporadic meteors and 5 satellites. Two satellites were close as they zoomed through Orion (one was likely ISIS 1), and another two crossed paths between Sirius and Procyon
Nova Centari was bright, at least 3.5.
Below is the breakdown of my observing, in 15 minute segments, from 4-4:15 I was also imaging Nova Centauri 2013, so I was not as effective watching for meteors as in the other time periods.
| Time (ACDST) | Geminids (magnitudes) | Sporadics |
| 3:07-3:15 | 2 (3,3) | - |
| 3:30-3:45 | 2 (3,-1) | - |
| 3:45-4:00 | 2 (4,-2) | 2 |
| 4:00-4:15 | - | 1 |
| 4:15-4:30 | - | - |
| 4:30-4:45 | 3 (3,-1,0) | - |
With the radiant 21 degrees above the horizon at my location, a limiting magnitude of 5 (averaging before and after Moonset), and something like 80% of my field of view unobstructed, I come up with a ZHR of 67 in the hour between 16:30 UT and 17:30 UT, which is consistent with the reported ZHR of 64 for 16:47 UT.
This is also consistent with the reports I have seen from South Australia (14-15 meteors in darker sky sites than mine). Other Australia sites were plagued by cloud.
In the northern hemisphere, where the radiant is higher,
All in all, not a bad Geminids, not as good from an Australian perspective as other years, and not as good as this years Aquariids, but not bad none the less.
Labels: Meteors, unaided eye
V1369 Nova Centauri 2013, 12th 13th brightest Nova since 1891
 |  |
| V1369 Nova Centauri 2013 just above beta Centauri at 4:05 am ACDST 15 December (17:35 Dec 14 UT). Stack of 10 images taken using a Canon IXUS, ASA 400, 10 second each exposure. Images registered and stacked with DeepSkyStacker, the converted to RGB and contrast adjusted in ImageJ. Click to embiggen (WARNING, very big file, around 40 Mb) | Labelled expanded image taken using the Canon IXUS, ASA 400, 15 second exposure, 3x Zoom. Central portion of the image to the left, with magnitude comparison stars and the nova indicated. Click to embiggen. |
While watching this mornings Geminid meteor shower I got to see V1369 nova Centauri 2013 at a decent height above the horizon, making it easier to estimate the magnitude of the lovely nova.
Note I said "easier", not easy. Even at 4 am the nova is still close to the horizon with significant atmospheric extinction (see top left image).
By unaided eye it looked to be about the brightness of Beta Muscae (magnitude 3.54). When you factor in atmospheric extinction this means its real magnitude is on the order of 3.4.
I also measured the intensities of the star on my photographic images (refernce stars Epsilon Cent, 2.3, Eta Crucis, 3.58, Beta Musc 3.54, Alpha Cricinus, 3.16 and Lambda Cent, 3.1) and did a linear regression. This gave a magnitude of 3.2 for the nova. This is a bit on the high side (star brightness on digital images do not always reflect their V magnitude), but makes me confident my estimate of 3.4 is in the right ball park.
This is consistent with other observers who found that the nova was around magnitude 3.4 at this time, coming down from a peak of 3.3 at 0 UT.
This makes V1369 Nova Centauri the brightest nova since 1999 (V382 Velorum, M2.6), and the
| Date | Nova | Magnitude |
| 1918 | V603 Aquilae | -1.4 |
| 1901 | GK Persei | 0.2 |
| 1942 | CP Puppis | 0.3 |
| 1925 | RR Pictoris | 1.2 |
| 1934 | DQ Herculis | 1.4 |
| 1975 | V1500 Cygni | 1.7 |
| 1920 | V476 Cygni | 2 |
| 1936 | CP Lacertae | 2.1 |
| 1999 | V382 Velorum | 2.6 |
| 1960 | V446 Herculis | 2.8 |
| 1946 | T Coronae Borealis | 3 |
| 1963 | V533 Herculis | 3 |
| 1912 | DN Geminorum | 3.5 |
This means that Nova Centauri 2013 will be visibel to the unaided eye for some time yet, go have a look!
Labels: binoculars, nova, unaided eye
Saturday, December 14, 2013
No Geminids for Me
So last night I got all set up for the Geminids, had my cameras and notebook out where I could get them as I went out the door so I wouldn't wake anyone scrabbling around. Junper, warm boots, red torch the lot. Went to bed reasonably early with a clear sky portending a good morning.
Alarm got me up and I wandered outside to cloud. Thick slabs of cloud. There were the occasional sucker holes, but these were nowhere near where either the Geminids nor the nova were.
I watched a while, just in case a decent gap opened up, but it didn't so I went back to bed. Today the sky is blue and clear of clouds, mocking me.
Reports from Australia that I have seen so far have been generally disappointing, only around 4-5 meteors an hour at best, well below the predictions from the meteor flux calculator. The data from the international meteor organisation shows reasonable rates in the Northern Hemisphere, so maybe we just had a lull.
I'll try and have another go tomorrow morning.
Alarm got me up and I wandered outside to cloud. Thick slabs of cloud. There were the occasional sucker holes, but these were nowhere near where either the Geminids nor the nova were.
I watched a while, just in case a decent gap opened up, but it didn't so I went back to bed. Today the sky is blue and clear of clouds, mocking me.
Reports from Australia that I have seen so far have been generally disappointing, only around 4-5 meteors an hour at best, well below the predictions from the meteor flux calculator. The data from the international meteor organisation shows reasonable rates in the Northern Hemisphere, so maybe we just had a lull.
I'll try and have another go tomorrow morning.
Labels: Meteors
Friday, December 13, 2013
Earth will NOT be hit by a "Wave of Killer ISON Debris"
 |  |
| Chart showing the predicted position of ISON as seen from STEREO H1A on 1 December 00:09 UT (click to embiggen). The Pleaides is the cluster at centre left in both images. | Image showing the actual position of ISON as seen from STEREO H1A on 1 December 00:09 UT (click to embiggen). The STEREO image has Earth and Mercury in the centre, these are not plotted on the star chart. |
Now that Comet C/2012 S1 ISON has fallen apart into a sad pile of gravel and dust, the fear merchants are at it again. With headlines like "COMET ISON'S KILLER Debris Wave Heading for EARTH" (I'm not going to link to the various pages and give them the page views, but you can google it yourself if you want to kill a few brain cells) the fear merchants are trying to scare people into thinkg a massive strom of rocks is headed our way.
But it isn't.
ISON's predicted orbit takes it well away from us, the nearest the pile of gravel formerly known as ISON comes to us is 0.43 AU (64,000,000 km), that's a bit under half the distance form Earth to the Sun, or the distance from Earth to Venus's Orbit.
i.e. Nowhere near us. I have previously checked ISON's orbit as it came out from its close approach to the Sun in the SOHO LASCO C3 images, it was right on track. I've done it again for ISON is the high resolution STEREO H1A imager images. This is more tricky as STEREO-A does not have the same field of view as Earth, so I needed to make a special ephemeris using JPL horizons based on the STEREO-A spacecraft's position.
They match to within 8 arc seconds. This means that ISON is on track in it's predicted orbit, and will come no closer to Earth than 0.43 AU. The rather compact debris trail will be high above Earth's orbit heading out to space. Oh yes, and the leftover material will not be "city sized". ISON itself was less than 1 Km in diameter (more like 600 meters), the biggest bits in the leftover gravel will be meter sized, at the outside as big as the Chelyabinsk meteor. If the debris cloud did come near us, we would get a pretty meteor display, but nothing more.
But of course, they will not come anywhere near us.
Labels: C/2012 S1 ISON, Meteors, Pseudoscience, Stereo Satellite
Thursday, December 12, 2013
The Aurora Chasers Handbook Launches
Oh yeah, and pictures, lots and lots of amazing aurora pictures by some outstandingly talented Australian auroraphiles from the Aurora Australis facebook group I am lucky to be a part of..
So if you want to lean about the Aurora Australis, find out how to see it, or just revel in the glorious imagery in the book, you could do worse than purchase a copy. You can buy it at this link here (or here).
Labels: aurora, public outreach
Nova Centauri 2013 still Bright (12 December 2013)
 |  |
| Nova Centauri 2013 captured with my Canon IXUS at ASA 400, 10 second exposure. Click to embiggen. | Nova Centauri 2013 captured with my Canon IXUS at 3x Zoom, ASA 400, 15 second exposure. Click to embiggen. |
Finally got to see Nova Centauri 2013 with my own eyes, magnitude probably between 3.6 and 3.9
Labels: binocular, nova, unaided eye
Wednesday, December 11, 2013
Nova Centauri 2013 brightens again (11 December 2013)
Nova Centauri faded from it's peak of around magnitude 3.5 to around 4.5, and now has bounced back again to magnitude 3.6-3.7 (see this magnitude plot from the AAVSO). I still have not seen it with my unaided eye, but I got another shot with iTelescope.
Exposure time was 10 seconds, and it is still overexposed. Compare this with my image from the 7th. No useful nearby reference stars to estimate the magnitude.
Labels: iTelescope, nova, unaided eye
Geminid Meteor Shower 13-14 December 2013
(click to embiggen).
The Geminids are unusual 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.
The Geminids are a fairly reliable meteor shower and this year moonlight will not significantly interfere.
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 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 14th, between 2:00 am and 4:00 am local time. 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 2013).
The International Meteor Organisations Live Geminid report will be useful to follow the shower.
At 1.00 am in the morning AEDST (midnight, AEST) Castor (alpha Geminorum) is about two handspans above the horizon and 10 handspans to the left of due north. Pollux, the other twin, is less than a handspan to the left 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 two minutes is an average, they won't turn up like a ticking clock but more or less randomly).
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 non 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 Jupiter and Mars will be nearby. 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.
Labels: Meteors
The Sky This Week - Thursday December 12 to Thursday December 19
The Full Moon is Tuesday December 17. Mars is
prominent in the early morning. Saturn rises higher in the morning sky.
Venus is easily visible late into the night in the western evening sky
above the Teapot. Jupiter is visible in the evening sky now, the Moon is close to Jupiter on the 19th. There
is a bright Nova near Beta Centauri that is currently visible with the unaided
eye. Geminid meteor shower on the morning of the 14th.
The Full Moon is Tuesday December 17.
Evening sky
looking west as seen from Adelaide at 21:00 pm ACDST on Saturday
December 14. Venus is high in the evening sky above the Teapot
asterism of Sagittarius. The inset shows the telescopic view of Venus.
Similar views will be seen elsewhere at the equivalent local times.
Click to embiggen.
Venus continues to fall back in the evening twilight. However, it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until late in the evening.
The brightest (spectacularly so) object above the western horizon it is still visible up to three hours or more after sunset (depending on how flat your western horizon is) when the sky is fully dark. Venus is beginning to sink to the horizon, but will be spectacular for many weeks hence.
Venus is in the Constellation of Sagittarius. It is a distinct crescent moon shape in even small telescopes. This week Venus is above the "Teapot" asterism of Sagittarius.
Evening sky on
Thursday December 19 looking north as seen from Adelaide at 2s:00 pm ACDST
in South Australia. The inset shows the view of Jupiter through a
telescope at this time. The Moon is close to Jupiter. Similar views will be seen elsewhere at the equivalent local time
(click to embiggen).
Jupiter is in the constellation Gemini. Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Jupiter is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars. Jupiter rises around 10:00 pm local daylight saving time, but is still best for telescopes in the early morning. Jupiter is close to the Moon on the 19th.
Morning sky on
Sunday December 15 looking east as seen from Adelaide at 5:00 am ACDST in
South Australia. Mars is high above the horizon, Saturn is low above
the horizon. Both are roughly equidistant from the bright star Spica.
Similar views will be seen elsewhere at the equivalent local time (click
to embiggen).
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
The northern horizon at 3:00 am ACDST as seen from Southern Australia
(northern Australia is similar but Gemini and the radiant is higher in
the sky) on Saturday December 14. The Geminid radiant is marked with a
cross.
The Geminids are a fairly reliable meteor shower and this year moonlight will not significantly interfere.
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 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 14th, between 1:00 am and 4:00 am local time. 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 2013).
At 1.00 am in the morning AEDST (midnight, AEST) Castor (alpha Geminorum) is about two handspans above the horizon and 10 handspans to the left of due north. Pollux, the other twin, is less than a handspan to the left again. The radiant is just below Pollux.
As well, Orion and the Hyades will be visible and bright Mars will be nearby. So it will be a quite nice morning for sky watching. Keep an eye out for satellites!
Location of Nova
Centaurus 2013 as seen looking north from Adelaide at 3:00 am ACDST
local time.The location is marked with a square. Similar views
will be seen at the equivalent local time in other Southern Hemisphere
locations. Click to embiggen.
UPDATE: Nova Centauri has re-brightened.
A new nova has been reported near beta Centauri. It is currently bright enough (magnitude4.5-5 back up to 3.6-3.7) to be
seen faintly with the unaided eye, and very easily in binoculars.
Unfortunately, you have to wait until early morning for the nova to be
heigh enough for a good look.
More detailed spotters charts and instructions are here.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
The Full Moon is Tuesday December 17.
Venus continues to fall back in the evening twilight. However, it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until late in the evening.
The brightest (spectacularly so) object above the western horizon it is still visible up to three hours or more after sunset (depending on how flat your western horizon is) when the sky is fully dark. Venus is beginning to sink to the horizon, but will be spectacular for many weeks hence.
Venus is in the Constellation of Sagittarius. It is a distinct crescent moon shape in even small telescopes. This week Venus is above the "Teapot" asterism of Sagittarius.
Jupiter is in the constellation Gemini. Mars is is in the constellation of Virgo. Saturn is in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Jupiter is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars. Jupiter rises around 10:00 pm local daylight saving time, but is still best for telescopes in the early morning. Jupiter is close to the Moon on the 19th.
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
The Geminids are a fairly reliable meteor shower and this year moonlight will not significantly interfere.
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 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 14th, between 1:00 am and 4:00 am local time. 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 2013).
At 1.00 am in the morning AEDST (midnight, AEST) Castor (alpha Geminorum) is about two handspans above the horizon and 10 handspans to the left of due north. Pollux, the other twin, is less than a handspan to the left again. The radiant is just below Pollux.
As well, Orion and the Hyades will be visible and bright Mars will be nearby. So it will be a quite nice morning for sky watching. Keep an eye out for satellites!
UPDATE: Nova Centauri has re-brightened.
A new nova has been reported near beta Centauri. It is currently bright enough (magnitude
More detailed spotters charts and instructions are here.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
Labels: weekly sky
Tuesday, December 10, 2013
Venus over the Harbour
Saturday, December 07, 2013
Southern Skywatch December, 2013 edition is now out!
The December edition of Southern Skywatch is now up.
There's a bit of planetary action this month with Venus, Jupiter and Mars meeting the Moon.
Mars climbs higher to the morning sky and is near the crescent Moon on the 26th. Jupiter climbs higher still and is also near the Moon on the19th.
Mercury is lost in the twilight.
Saturn returns to the morning sky and is close to the Moon on the 29th.
The Geminid meteor shower is best on the morning of the 14th, and some decent meteors should be seen.
Labels: southern skywatch
Venus and the Moon, 6 December 2013
 |  |
| Venus in the daylight, captured with my Canon IXUS at 3x Zoom, ASA 400, auto setting about an hour before sunset. Click to embiggen to see Venus clearly. | Venus in the twilight, captured with my Canon IXUS at 3x Zoom about half an hour after sunset. Click to embiggen just because you can. |
Venus and the Moon were close last night, and it was an excellent opportunity to see Venus in the daylight, which I did, easily.
Labels: Daylight, Daytime, Moon, Venus
Nova Centauri 2013 (7 December 2013)
Exposure time was 30 seconds, and it is still overexposed. I'll try again tomorrow. No useful nearby reference starts (come back T12 all is forgiven) to estimate the magnitude, looks like it has maxed out at around magnitude 3.6-3.7 from recent reports.
One day the clouds here will lift and I can see it with my own eyes.
Labels: iTelescope, nova, unaided eye
Wednesday, December 04, 2013
A Bit of a Comet ISON Wrap-up.
 |  |
| Comet C/2012 S1 ISON (indicated) has survived its passage around the Sun. It is much faded, and is probably no more than a pile of rubble gently dissipating into space. image from 30 Nov 2013 | Animation of 20 images from 30 November to 1 December 2013 showing ISONs progressive fading |
Being off at a conference and away from my astronomy software I have not been able to blog ISONs going saga. After initially recovering from its beating as it passed perihelion, it has continued to fade as it passed from the LASCO C3 imager to the STEREO H1A imager.
While still visible in H1A up until the time it passed out of the H1A field of view, it is very much faded, and it is uncertain if the remnants will be visible in amateur instruments when it gets high enough in dark sky several days from now.
I've done a quick image and animation of the high resolution H1A images available now, this give a more realistic view than the medium resolution highly enhanced images that have been available until now.
Labels: C/2012 S1 ISON, Soho, Stereo Satellite
ALERT! Bright (Mag 5!) Nova in Centaurus
 |  |
| Location of Nova Centaurus 2013 as seen looking north from Adelaide at 3:00 am ACDST local time.The location is marked with a square. Similar views will be seen at the equivalent local time in other Southern Hemisphere locations. Click to embiggen. | Black and White map suitable for printing at a scale useful for binoculars, view from the Southern hemisphere, click to embiggen. The circle is the approximate field of view of 10x 50 binoculars. A high definition PDF map that is better for printing is here. |
UPDATE! the nova has now been reported to be as bright as magnitude 3.8! This makes it the brightest nova in years, and beats Nova Delpinis earlier this year.
Via John Goodrick and Carl Gruber, a magnitude 5 nova has been discovered in Centaurus http://www.cbat.eps.harvard.edu/unconf/followups/J13544700-5909080.html
This nova has now been independently confirmed and is currently around magnitude 5.0. It has been imaged by many amateurs. An example image is here.
Location R.A. = 13 54 47.00, Decl.= -59 09 08.0 (J2000 coordinates)
It is bright enough to be seen with the unaided eye under dark sky conditions but most people will need binoculars to see it clearly. PDF map here. Unfortunately it is best seen in the early morning when the pointers are at their highest.
 | |
| Stellarium simulation of the view through binoculars (actually this is equivalent to a few binocular fields stitched together for ease of explanation). The square is the location of the nova. The guide star HIP 66849 is indicated. Click to embiggen. |
At magnitude 5 (or so) the nova is readily visible if you know where to look, but is a bit nondescript. It's best to hunt it with a printout of this binocular location map in your hand (use a torch with red cellophane over the end to not destroy you night vision, wait at least 5 minutes before searching so your eyes accommodate to the dark). However, this description may help you find it in binoculars as well.
This description will work for between 2-4 am, local time. Facing south, the southern cross is seen clearly to the south east (see top map above). Just below the cross, the two brightest stars above the horizon are beta (the top blue-white star, also known as Hadar) and alpha (the bottom orange star, aslo known as Rigel Kentaurus) Centauri.
Above and to the left of beta Centuari by about 3 finger widths is the dim star HIP 66849. at magnitude 5.37 it is the brightest star aside from the nova that is near beta Centauri. The nova is almost directly between these two and currently just a trace brighter than HIP 66849.
Aim your binoculars at beta Centauri. Through the binoculars you will see two brightish stars off two the left. The one in the middle is the nova (again, consult the maps for guidance, it may need several back and forth for you to be sure you have seen it).
Labels: binocular, nova, unaided eye
The Sky This Week - Thursday December 5 to Thursday December 12
The First Quarter Moon is Tuesday December 10. Mars and Jupiter are prominent in the early morning. Saturn rises higher in the morning sky. Venus is easily visible late into the night in the western evening sky above the Teapot. It is not far from the Moon on the 5th and 6th. There is a bright Nova near Beta Centauri that is visible with the unaided eye.
The First Quarter Moon is Tuesday December 10.
Evening sky looking west as seen from Adelaide at 21:00 pm ACDST on Thursday December 5. Venus is quite high in the evening sky above the Teapot asterism of Sagittarius. The inset shows the telescopic view of Venus. Similar views will be seen elsewhere at the equivalent local times. Click to embiggen.
Venus continues to fall back in the evening twilight. However, it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until late in the evening.
The brightest (spectacularly so) object above the western horizon it is still visible up to three hours or more after sunset (depending on how flat your western horizon is) when the sky is fully dark. Venus is beginning to sink to the horizon, but will be spectacular for many weeks hence.
Venus is in the Constellation of Sagittarius. It is a distinct crescent moon shape in even small telescopes. This week Venus is above the "Teapot" asterism of Sagittarius and is not far from the crescent Moon on December 5 and 6
Morning sky on Tuesday December 10 looking north as seen from Adelaide at 2:00 am ACDST in South Australia. The inset shows the view of Jupiter through a telescope at this time. Io and its shadow is transiting Jupiter at this time, Similar views will be seen elsewhere at the equivalent local time (click to embiggen).
Jupiter is in the constellation Gemini. Mars is is in the constellation of Virgo. Saturn and Mercury are in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Jupiter is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars. There are some good Moon events on the10th at around 2 am local daylight saving time. Jupiter rises around 10:00 pm local daylight saving time, but is still best for telescopes in the early morning.
Morning sky on Sunday December 8 looking east as seen from Adelaide at 5:00 am ACDST in South Australia. Mars is high above the horizon, Saturn is low above the horizon. Both are roughly equidistant from the bright star SPica/ Similar views will be seen elsewhere at the equivalent local time (click to embiggen).
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
Location of Nova Centaurus 2013 as seen looking north from Adelaide at 3:00 am ACDST local time.The location is marked with a square. Similar views
will be seen at the equivalent local time in other Southern Hemisphere
locations. Click to embiggen.
A new nova has been reported near beta Centauri. It is currently bright enough (magnitude 5) to be seen faintly with the unaided eye, and very easily in binoculars. Unfortunately, you have to wait until early morning for the nova to be heigh enough for a good look.
More detailed spotters charts and instructions are here.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
The First Quarter Moon is Tuesday December 10.
Venus continues to fall back in the evening twilight. However, it can easily be seen shortly after sunset (indeed, with a little effort you can see it before sunset) until late in the evening.
The brightest (spectacularly so) object above the western horizon it is still visible up to three hours or more after sunset (depending on how flat your western horizon is) when the sky is fully dark. Venus is beginning to sink to the horizon, but will be spectacular for many weeks hence.
Venus is in the Constellation of Sagittarius. It is a distinct crescent moon shape in even small telescopes. This week Venus is above the "Teapot" asterism of Sagittarius and is not far from the crescent Moon on December 5 and 6
Jupiter is in the constellation Gemini. Mars is is in the constellation of Virgo. Saturn and Mercury are in Libra.
Mars rises still higher in the morning twilight, and is visible well before twilight.
Jupiter is now well above the northern horizon near the bright stars Castor and Pollux, the twins of Gemini. It is quite easy to see in the morning sky well into the twilight. Jupiter's Moons are now readily visible in binoculars. There are some good Moon events on the10th at around 2 am local daylight saving time. Jupiter rises around 10:00 pm local daylight saving time, but is still best for telescopes in the early morning.
Saturn is visible low in the eastern horizon before dawn. It will be difficult to see unless you have a flat, level horizon.
Mercury is lost in the twilight.
A new nova has been reported near beta Centauri. It is currently bright enough (magnitude 5) to be seen faintly with the unaided eye, and very easily in binoculars. Unfortunately, you have to wait until early morning for the nova to be heigh enough for a good look.
More detailed spotters charts and instructions are here.
There are lots of interesting things in the sky to view with a telescope. Especially with Venus 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.
Printable PDF maps of the Eastern sky at 10 pm AEDST, Western sky at 10 pmAEDST. For further details and more information on what's up in the sky, see Southern Skywatch.
Labels: weekly sky
Monday, December 02, 2013
They do better Loos here
Click to read about or order
Click to read about or order
Click to read about or order
Click to read about or order
