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Tuesday, January 27, 2015

 

The Sky This Week - Thursday January 29 to Thursday February 5

The Full Moon is Wednesday February 4. Venus is prominent in the twilight evening sky. Mars is just visible in the early evening twilight and is coming closer to Venus. Jupiter is visible in the late evening sky and is visited by the Moon on February 4. Saturn is in the head of the Scorpion.

The Full Moon is Wednesday February 4.

Evening sky on Saturday January 31 looking west as seen from Adelaide at 21:00 (9:00 pm) ACDST in South Australia.  Mars is low in the twilight, with Venus below it. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Venus is easy to see low above the western horizon in the twilight. At civil twilight, half an hour after sunset, it is around one and a half hand-spans above the horizon. Venus is also a hand-span below Mars.

Mars  is still seen low in the western evening sky, setting around 10:00 pm daylight saving time (just as twilight ends). Mars is becoming harder and harder to see as it lowers deeper into the twilight.

As the week goes on Mars and Venus approach each other, the pair will be closest on the  22nd.

Evening sky on Wednesday February 4 looking north-east as seen from Adelaide at 22:00 ACDST showing Jupiter.  The Full Moon is close to Jupiter at this time. The inset shows Jupiter's Moons at 22:00  on the 2nd. Jupiter is the brightest object above the north-eastern horizon. (click to embiggen).


 Jupiter  is now easily seen  in the late evening sky. It is the brightest object above the north-eastern horizon when twilight ends. It is not far from the bright star Regulus in the sickle of Leo (this forms the head of the constellation of the  Lion). On February 4th the Moon provides a guide yo Jupiter, forming a triangle with Jupiter and the bright star Regulus (Jupiter is obviously brighter than Regulus in this triangle)

Jupiter is high enough for telescopic observation just before midnight, although its visibility will improve in the coming weeks. Jupiter's Moons will be putting on a good display in both binoculars and small telescopes. On the 2nd Ganymede and its shadow transits the face of Jupiter for around the end of twilight for about an hour.

Morning sky on Sunday February 1 looking east as seen from Adelaide at 5:00 am ACDST .   Saturn is in the head of the Scorpion, not far from Antares at this time. (click to embiggen).

Saturn climbs still higher in the morning sky. It is now easily visible before twilight near the head of the constellation of the Scorpion not far from the bright red star Antares. The sight of the distinctive constellation of the Scorpion curled above the horizon, with bright Saturn in its head, is very nice indeed.


Mercury  returns to the morning sky this week, but is low in the twilight and will be too hard to see. However, in the coming weeks Mercury will be putting on a decent display.


There are lots of interesting things in the sky to view with a telescope. Especially with the comet in the early evening 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 AEST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.

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Success! 2004 BL86's flyby seen (26 January 2015)

My sketch of the flyby of Near Earth Asteroid 2004 from 11:40 ACDST to 11:58 ACDST. 114mm Newtonian with 25 mm Plossel eyepiecePredicted chart of the flyby in SkyMap

After a busy Australia day of waking up late, walking down the beach to the Australia Day concert to buy ice- creams, a Barbie with friends and watching the fireworks, I set up the telescope to camp out on 11 Puppis to watch the flyby of Near Earth Asteroid 2004 BL86.

And failed utterly. I had misunderstood the orientation of the images in to scope, and by the time I had confirmed which part of the image was north, the asteroid was long gone.

Once I has sorted my orientation out (with much hopping back and forth to the computer screen inside) I chose the undistinguished star HIP 39095 as my target, as the asteroid passed close to it. I star hopped down, set up about 10  minutes beforehand, sketched the field (and confirmed that I did have the RIGHT field and which way the asteroid would be going as seen though the scope), then waited.

I did a bit of back and forthing to get the areas I wanted directly in the field, with particular stars picked out as the asteroid passed close to them.

And then I saw it. Drifting slowly into the field. I really needed averted vision to see it properly, on the basis of the other stars in the field I would put it at around magnitude 10.4, rather than the predicted 10.1 (I could see mag 10.2 stars okay). It was also running about 5 minutes ahead of schedule, but it's track was pretty close to predicted.

I watched it drift close to, then past, several dim stars in the field, and then out of the field in around 15 minutes. My sketching is pretty rubbish, but is surprisingly close to the actual chart. The spacing of the asteroid positions are not fantastically accurate, but the timed locations next to actual stars is.

I hope I can get up at 4:00 am to see the close pass to M48 Tuesday morning, also hoping the Mayhill iTelescopes aren't clouded out. The SSO ones are, so unless the skies clear soon I don't think I will get any close approach images form SSO.

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Sunday, January 25, 2015

 

UPDATE: Seeing the Close Flyby of NEO 2004 BL86 10 pm 26 January, 2015

The position of asteroid 2004 BL68 as seen at 22:00 ACDST on the evening of 26 January 2015 from Adelaide. Similar views will be seen at 22:30 AEDST and 21:30 AEST. Click to embiggenApproximate binocular view of asteroid 2004 BL68 as seen at 22:00 and 23:00 ACDST on the evening of 26 January 2015 from Adelaide. Similar views will be seen at 22:30  and 23:30 AEDST and 21:30- 22:30  AEST. Click to embiggen

In my previous article on 2004 BL86 I explained in detail how to see this NEO at its brightest ... at around 4:30 am in the morning when it is close to the bright open cluster M48. For those of you who want to see it on the night of the 26th, before heading to bed, I've created these instructions.

You will need a telescope, not a fancy one, but a telescope none the less. Finding the asteroid will be harder as it is dimmer, and there is no obvious bright feature to use as a guide. But while harder it is well worth the effort.

Printable black and white horizon chart facing east an hour and a half after sunset on the 26th showing the location of 2004 BL86 as seen from Adelaide. Similar views will be seen from East coast and central locations at the equivalent local time. WA sees the asteroid further along in its path. Click to embiggen and printPrintable black and white binocular chart  showing the location of 2004 BL86 at 22:00 to midnight  ACDST on the evening of 26 January 2015 from Adelaide. Similar views will be seen from 22:30 AEDST and 21:30 AEST. The large circle is approximately the field of view of 10x50 binoculars. The small circle the approximate field of view of a 25 mm eyepiece with a 114 mm Newtonian telescope. Click to embiggen and print.

To find the asteroid, again we will use bright stars as a landmark. If you draw a line between Jupiter and Canopus (the brightest  and third brightest objects in the sky at this time), then draw a line perpendicular from Sirius (the second brightest object in that part of the sky) to the Jupiter - Canopus line, the intersection is where the asteroid will be.

In binoculars or a telescopes finder scope you will see a triangle of stars. The faint star at the apex of the triangle is 11 Pupis. The asteroid zooms past this star as seen from the eastern and central states. From WA, by the time the sky is darkenough, the asteroid is well below 11 Puppis, but you can use the charts to sweep down and find it.

Printable black and white binocular chart  showing the location of 2004 BL86 at 22:00 to midnight  ACDST on the evening of 26 January 2015 from Adelaide. The circle the approximate field of view of a 25 mm eyepiece with a 114 mm Newtonian telescope. The orientation is upside down from the binocular map as telescopes invert the image. Click to embiggen and print.

 With your telescope a wide field eye piece, first centre 11 Pupis in the eyepiece, then move it so 11 Puppis is at the western edge of the eyepiece. The asteroid should be visible as a faint dot on the western side, moving slowly but inexorably across the stars.

The printable charts above will be needed help you find the asteroid.Remember, when looking for the asteroid allow at least 5 minutes or more (10 is better) for your eyes to adjust and become dark adapted. Here's some hints on dark adaption of your eyes. If using the charts above, cover your torch with red cellophane so as to not destroy your night vision.

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Saturday, January 24, 2015

 

I'm on the Radio this Sunday January 25, 2015

The position of asteroid 2004 BL68 as seen at astronomical twilight on the morning of 27 January 2015 (4:50 am ACDST, one and a half hours after sunset) from Adelaide. Click to embiggen

On the morning  of Sunday 25 January I'll be on ABC local radio (Adelaide 891 AM) with Ashley Walsh, going live around 11:40 am ACDST (11:10 AEDST, 10:10 AEST). I'll be talking about the close flyby of Near Earth Asteroid 2004 BL86 and how to see it and what's coming up in 2015. So listen if you can (they doing streaming, so even if you are not in Adelaide you can catch this on your computer).

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Friday, January 23, 2015

 

Seeing the Close Flyby of NEO 2004 BL86 26 - 27 January, 2015

The position of asteroid 2004 BL68 as seen at astronomical twilight on the morning of 27 January 2015 (4:50 am ACDST, one and a half hours after sunset) from Adelaide. Click to embiggenThe position of asteroid 2004 BL68 as seen at astronomical twilight on the morning of 27 January 2015 (4:50 am ACDST, one and a half hours after sunset) from Adelaide. Click to embiggen
Printable black and white horizon chart facing west an hour and a half before sunrise on the 27th showing the location of 2004 BL86 as seen from Adelaide. Similar views will be seen from Southern Hemisphere locations at the equivalent local time. Click to embiggen and printPrintable black and white binocular chart an hour and a half before sunrise on the 27thshowing the location of 2004 BL86. The large circle is approximately the field of view of 10x50 binoculars. The small circle the approximate filed of view of a 25 mm eyepiece with a 114 mm Newtonian telescope. Click to embiggen and print

Near Earth Asteroid  2004 BL68 will  come close to Earth on 16:20 UT 26 January at distance of 0.008 AU (around 3.1 Earth-Moon distances). It is brightest at 04:00 UT on the 27th though. It has an estimated diameter of 680m (a bit over half a kilometer). The asteroid will be a reasonably bright magnitude 9.0 at closest approach, and it comes close to the iconic Beehive cluster when it is still bright.

The flyby of 2004 BL86 will be the closest by any known asteroid of this size until 2027 when asteroid 1999 AN10 goes past Earth. It is also the brightest since 2012 DA14 in 2013.

Unfortunately, from Australia the asteroid is below the horizon at its brightest. We get to see it when it is between magnitudes 10-9.6. The theshold for unaided eye viewing is magnitude 6, so the asteroid is quite dim. Australians can see the asteroid move from Puppis (on the late evening of the 26th, Australia day) through Monocerous and into Hydras.

While the asteroid can be picked up by high end binoculars under dark sky conditions, for most observers small telescopes will be required. My small 114 mm Newtonian with a 25 mm eyepiece allows me to see stars dimmer than magnitude 10.

The printable charts above will also help you find the asteroid. For telescope users, the image will be upside down compared to the charts (so hold the binocular/telescope chart upside down). Remember, when looking for the asteroid allow at least 5 minutes or more (10 is better) for your eyes to adjust and become dark adapted. Here's some hints on dark adaption of your eyes. If using the charts above, cover your torch with red cellophane so as to not destroy your night vision.

When looking for the asteroid in the early morning, we have a good signpost and viewing opportunity. The asteroid comes close to (eastern states) and crosses (western and central states) the relatively bright (magnitude 5.8) open cluster M48 before astronomical twilight. If you find the open cluster then you can camp out on it and watch the asteroid creep towards it.

You can find the cluster fairly easily. If you draw a line between Jupiter and Sirrius (the two brightest objects in the sky at this time), then draw a line perpendicular from procyon (the third brightest object in that part of the sky) to the Jupiter - Sirius line, you should be able to (just see) M48. It will be quite obvious in binoculars or a telescopes finder scope.

With the cluster in view, sweep slowly south around half a field of view at a time. The asteroid may be initially difficult to distinguish as a fairly dim dot, even in a telescope, but it is the only dimmish dot moving slowly and relentlessly towards the cluster.  It may take half an hour to cross the field of view of a wide field eye-piece, but it's motion is fast enough to pick it up.

For central states the asteroid crosses the cluster from around 4:40 to 4:50 am ACDST (3:40-3:50 ACST), for Western Australia the asteroid crosses M48 between roughly 2:10 am - 2:20 am AWST (it is much higher in the sky, so easier to pick up in WA). In the eastern states the asteroid is two cluster widths away from M48 at astronomical twilight (roughly 3:48 am AEST and 4:36 am AEDST).

For those of you familiar with charts and ephemerides, you can generate your own ephemeris using the MPEC ephemeris generator. http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Use your longitude and latitude for an ephemeris for your location, remember the times are in UT adn it is best to choose and observing interval of around 15 minutes as the asteroid is moving relatively quickly.

Here's some NEO's I've captured in the past.


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Thursday, January 22, 2015

 

Venus and the Crescent Moon - 22 January 2015

Venus and the crescent Moon imaged at around 21:15 ACDST form Largs North, using my Canon IXUS ASA 400, 1 sec exposure. click to embiggen.The paired imaged on 3X Zoom, then the image cropped to emphasise the pair. Click to embiggen.

After returning from putting EldestOne on a Melbourne bound bus to start sorting out some Uni things, I saw the most gorgeous sunset. Despite the clouds, I was able to capture Venus and the crescent Moon. Unfortunately, Mercury had sunk in the horizon murk by the time the clouds let me see the planets.

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AGAIN! Aurora happening NOW! 22 January 10 pm

It's on AGAIN! (but this time before midnight). Aurora are being seen
with the unaided eye in Tasmania NOW!  Naked eye beams are being
reported in  Margate, Ralphs Bay, Howden and Stanford. Unaided eye glows are being
reported in Port Fairy and Barnsdale Victoria!. The auroral intensity may fade in
and out, so be prepared for lulls in the activity. Solar wind
Velocity: Velocity: 477 km/sec Bz: -4.0 nT Hobart K-Index 3 (this K index
was the value  associated with this mornings display).

Dark sky sites have the best chance of seeing anything, and always
allow  around 5 minutes for your eyes to become dark adapted.
As always look to the south for shifting red/green glows, beams have
been reported too.

The all sky aurora camera in Southern Tasmania at Cressy may be of
help in monitoring for aurora, but seems to be offline at the moment
http://www.ips.gov.au/Geophysical/4/2

Further monitoring at
http://www.ips.gov.au

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Aurora happening NOW! 22 January 2015 1:00 am

The solar wind flowing from a coronal hole has produced an unexpected aurora. Aurora are being seen with the unaided eye in Tasmania NOW!  Naked eye beams are being reported in Howden, Tinderbox, Evandale and Hobart. The auroral intensity may fade in and out, so be prepared for lulls in the activity. Solar wind Velocity: 401 km/sec Bz: -5.0 nT

Dark sky sites have the best chance of seeing anything, and always allow  around 5 minutes for your eyes to become dark adapted.
As always look to the south for shifting red/green glows, beams have been reported too.

The all sky aurora camera in Southern Tasmania at Cressy may be of help in monitoring for aurora
http://www.ips.gov.au/Geophysical/4/2

Follow the solar weather indices at
http://www.ips.gov.au

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Mercury, Venus and the Crescent Moon, Thursday January 22, 2015

Evening sky on Thursday January 22 looking west as seen from Adelaide at 21:00 (9:00 pm) ACDST in South Australia.  Mars is low in the twilight, with Venus and the Moon close together below. Mercury is deep in the twilight. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Just a reminder that  on the 22nd Venus, the thin crescent Moon and Mercury form a triangle low in the twilight.

While Venus is bright you will still need a reasonably flat, clear horizon to see all three objects, although you may need binoculars to see Mercury. Venus provides a helpful signpost to finding Mercury which is below and to the left of Venus.

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Wednesday, January 21, 2015

 

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

The First Quarter Moon is Tuesday January 27. Venus is prominent in the twilight evening sky while Mercury falls back to the horizon. The pair are visited by the Moon on Jan 22. Mars is just visible in the early evening and is visited by the Moon on Jan 23. Jupiter is visible in the late evening sky. Comet C/2102 Q2 Lovejoy is lost from view. Saturn is in the head of the Scorpion.

The First Quarter Moon is Tuesday January 27.


Evening sky on Thursday January 22 looking west as seen from Adelaide at 21:00 (9:00 pm) ACDST in South Australia.  Mars is low in the twilight, with Venus and the Moon close together below. Mercury is deep in the twilight. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Mercury  is low in the twilight, and by the end of the week will be too hard to see. Venus provides a helpful signpost to finding Mercury which is below and to the left of Venus. On the 22nd Venus, the thin crescent Moon and Mercury form a triangle, although you may need binoculars to see Mercury. You will need a reasonably flat, clear horizon to see it.

Venus is now easy to see low on the western horizon in the twilight. At civil twilight, half an hour after sunset, it is well over a hand-span above the horizon. While Venus is bright you will still need a reasonably flat, clear horizon to see it, although as the week goes by it is easier and easier to pick out. On the 22nd Venus, the thin crescent Moon and Mercury form a triangle.

Mars  is still seen low in the western evening sky, setting before 10:30 pm daylight saving time (shortly after twilight ends). Mars is becoming harder and harder to see as it lowers deeper into the twilight. On the 23rd the crescent Moon is close to Mars.

Morning sky on Saturday January 24 looking east as seen from Adelaide at 5:00 am ACDST .   Saturn is in the head of the Scorpion, not far from Antares at this time. (click to embiggen).

Saturn climbs higher in the morning sky. It is now easily visible in the early twilight near the head of the constellation of the Scorpion not far from the bright red star Antares. The sight of the distinctive constellation of the Scopion curled above the horizon, with bright Saturn in its head, is very nice indeed.

 Jupiter  is prominent in the morning sky, and is easy to see as the brightest object above the northern horizon before twilight. It is now not far from the bright star Regulus in the sickle of Leo (this forms the head of the constellation of the  Lion).

Jupiter is high enough for good telescopic observation before astronomical twilight. Jupiter's Moons will be putting on a good display in both binoculars and small telescopes.

Jupiter enters the evening sky just before 10 pm daylight saving time, where it is the brightest object above the north-eastern horizon. It is now in a decent position for telescope viewing just before midnight, although still best in the early morning.


Evening sky on Sunday January 25 looking north  as seen from Adelaide at 22:00 (10:00 pm) ACDST in South Australia. Comet C/2014 Q2 Lovejoy is below the Pleiades.  Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

C/2014 Q2 Lovejoy is dimming in the sky. This will be the least week we can effectively see the comet before it passes completely into northern hemisphere skies.

While the comet is reasonably bright now (estimates between magnitude 4.0 and 4.5) it is slowly fading as it heads towards the horizon where horizon murk makes it even harder to see. Also this week the Moon brightens compounding the comets visibility difficulties. It is still easily visible in binoculars but will be much more difficult to see by the weeks end. Binoculars or small telescopes show it as a definite fuzzy disk about a quarter of the size of the Moon. In modest sized telescopes the faint thin tail can be seen. Instructions on viewing the comet and printable finding charts can be found here.

There are lots of interesting things in the sky to view with a telescope. Especially with the comet in the early evening 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 AEST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.

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Monday, January 19, 2015

 

Comet C/2014 Q2 Lovejoy's Tail meets the Pleiades (19 January 2015)

Comet C/2014 Q2 Lovejoy on the 19th of January as seen from Adelaide at Astronomical twilight (an hour and a half after sunset). It is not far from the Pleiades, and  people with serious astrophotography kit may capture the tail as it passes over the Pleiades (click to embiggen).

Over the past few days comet C/2014 Q2 Lovejoy has been edging closer to the beautiful star cluster the Pleiades. They were closest last night, on the 18th, but tonight they will still be close, a bit too far to get in one binocular field, but very nice both in the sky and binoculars.

My slightly rubbish image of the comet and the Pleiades from last night. If you click and embiggen the image, you might just possibly see the hint of a tail. or not.

However, if you have some serious camera kit, you might just be able to get the comets tail crossing the Pleiades. Here's Chris Wyatt's image of the 17th. With a good DSLR you should be able to pick it up too. The tail has been an absolute delight in astrophotographs, barely visible to the eye in telescopes though.

So, go out tonight and have a look. People in Southern Australia have a fairly narrow window before the comet is too low to the horizon (from about 10:00 pm to 11:30 pm), but northern Australians have a better view.


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