Astroblog

The First Quarter Moon is Saturday, August 18.  4 bright unaided eye planets can be seen in the evening sky. Venus is high in the early evening sky . Jupiter is past opposition, but is still big and bright in telescopes. The Moon visits Jupiter on the 17th. Jupiter is closest to the bright star alpha Librae (Zubenelgenubi) between the 16th and 19th. Saturn and  Mars are visible in the evening skies and are visited by the waxing Moon on the 21st ad 23rd respectively. Mars is just past opposition but is still bright and big in even small telescopes.

The First Quarter Moon is Saturday, August 18. The Moon is at apogee, when it is furthest from the Earth, on the 23rd.

Evening twilight sky on Saturday August 18 looking west as seen from Adelaide at 19:12 ACST (90 minutes after sunset). Venus is high above the horizon and coming closer to Spica. The inset shows  simulated telescopic views of Venus as seen with a 5mm telescopic eyepiece (compare with Jupiter, Saturn and Mars).

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

Brilliant Venus is visible high in the evening until well after full dark. Venus is visible to the unaided eye from before sunset, easy to see shortly after sunset and can viewed well after 90 minutes after sunset. During the week Venus moves further towards the bright star Spica.

Whole sky view of the evening sky on Saturday August 18 as seen from Adelaide at 19:12 ACST (90 minutes after sunset).  Four bright planets and the waxing Moon are visible in the evening sky.




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


Evening sky on Friday August 17 looking North  as seen from Adelaide at 19:12 ACST (90 minutes after sunset). Jupiter is well above the horizon, close to the bright star alpha Librae and close to the waxing Moon.

The inset is a simulated telescopic view of Jupiter and its moons at 19:12 ACST (90 minutes after sunset). Jupiter is  shown as seen with a 5mm telescopic eyepiece.

Similar views will be seen throughout Australia 90 minutes after sunset (click to embiggen).

Evening sky on Tuesday August 21 looking east  as seen from Adelaide at 19:14 ACST (90 minutes after sunset). Saturn and Mars are clearly visible with the waxing Moon close to Saturn. The insets are simulated telescopic views of Saturn and Mars as seen with a 5mm telescopic eyepiece.

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

 Venus  is  readily visible above the horizon in the early evening.  It is bright enough to be visible from just on sunset and to well past 90 minutes after sunset at full dark, when it is two and a half hand-spans above the horizon.  During the week Venus moves closer to the bright star Spica.

Mercury is deep in the twilight in the morning skies and very difficult to see.

Jupiter  is high in the early evening sky above the northern horizon. It was at Opposition on the May 9th, and is still visible most of the night. It is  a good telescopic object in the mid to late evening and is highest around 17:15 local time before the Sun sets. There are some good Jovian Moon events this week. This week Jupiter is coming closer to the bright star alpha Librae (Zubenelgenubi).

 Mars is in Capricornius and is readily seen in the evening. Mars was at opposition last month on July 27th,  when it was biggest and brightest as seen from Earth. This was the best opposition since 2003. However Mars will remain bright and large in even small telescopes for some time. In a telescope you may see a few features as the huge dust storm sweeping the planet continues to subside.  A guide to observing Mars at the time is at my Mars Opposition page. The Moon is close to Mars on the 23rd.

Saturn is climbing higher the early evening sky, and is now a good telescopic object in the mid to late evening sky. It was at opposition, when Saturn is biggest and brightest as seen from Earth, on June the 27th. It is within binocular range of  the Trifid and Lagoon nebulae. However the increasing Moon light makes seen these nebula more difficult, especially on the 21st, when the waxing Moon is close to Saturn.

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/

Labels: weekly sky

Western horizon as seen from Adelaide on Tuesday  14 August at 5:00  pm, 45 minutes before sunset. Venus is about a hand-span above the crescent Moon. Similar views will be seen elsewhere in Australia 45 min before local sunset (click to embiggen)	Western horizon as seen from Adelaide on Wednesday  15 August at 5:00  pm, 45 minutes before sunset. Venus is about a hand-span below the crescent Moon. Similar views will be seen elsewhere in Australia 45 min before local sunset (click to embiggen)

As regular readers of this blog know, I'm obsessed with seeing Venus in the daytime.

Venus is currently bright enough to see during the daylight. However, finding a bright dot in the vast amount of blue can be challenging. It is easier to locate Venus if there is a handy foreground object nearby to use as reference. The Moon is such an object, fairly easy to spot making it a handy guide. 

On the 14th, and then again on the 15th, the crescent Moon is about a hand-span from Venus, an excellent opportunity for finding Venus in the daylight.

Look for the thin crescent Moon, and Venus should be visible as a bright dot just above it (14th) or below it (15th). The images above should help locate it. It's best to look in the afternoon when the Sun is low and the sky is less bright. Make sure the Sun is hidden behind something solid like a building or a wall when you are looking for Venus, not trees or your hand. Exposing your eyes directly to the glare of the Sun can be very dangerous and you could potentially lose your sight.



You may need to use binoculars at first to pick up Venus near the moon, but once you have spotted it it will be obvious (again make sure you practise sun safety when observing with binoculars).

I used a corner of the house and pergola to shut out the Sun and frame the Moon-Venus combination for previous daylight Venus adventures.

You may also use mobile phone apps such as Google sky map to locate the Moon and Venus in the vasty blue.

If you miss this opportunity, locate Venus around half an hour after Sunset, and find a convenient marker (a tree, a telephone pole or something like that) close by to Venus from a fixed position in your yard. Note the relative position of Venus and features on the marker. Next day, go to your viewing position about 5 minutes after Sunset and again note Venus's location. The next day, look 5 minutes before Sunset and note the location. And so on until you can see Venus well before Sunset.

Do remember to be very careful not to look directly at the Sun when doing all of this. Chose your viewing location so that the Sun will be hidden well behind some solid object at all of your projected viewing times.


Good luck Venus hunting.

Labels: Daylight, Daytime, Moon, unaided eye, Venus

The New Moon is Saturday, August 11.  4 bright unaided eye planets can be seen in the evening sky. Venus is high in the early evening sky and is close to the crescent Moon on the 14th and 15th. Jupiter is past opposition, but is still big and bright in telescopes. Mars and Saturn are visible in the evening skies. Mars is just past opposition but is still bright and big in even small telescopes. Perseid meteor shower visible in northern Australia.

The New Moon is Saturday, August 11. The Moon is at perigee, when it is closest to the Earth, on the 11th.

Perseid radiant as seen from Darwin at 5:00 am local time, August the 13th, looking north. Click to embiggen.

The Perseid Meteor Shower peaks on the morning of Thursday August 13. Despite this being a quite reasonable meteor shower in the northern hemisphere, for most of Australia, the radiant is below the horizon, and only the very occasional meteor shooting up from the northern horizon will be seen. Anyone south of Brisbane will see only the occasional meteor, say maybe one or two per hour, the further north of Brisbane you are, the more meteors you will see. A full observing guide is at my Perseid page.

Evening twilight sky on Tuesday August 14 looking west as seen from Adelaide at 19:09 ACST (90 minutes after sunset). Venus is high above the horizon and close to the crescent Moon. The inset shows  simulated telescopic views of Venus as seen with a 5mm telescopic eyepiece (compare with Jupiter, Saturn and Mars).

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

Brilliant Venus is now visible in the evening until well after full dark. Venus is visible to the unaided eye from sunset, easy to see 30-60 minutes after sunset and can viewed well after 90 minutes after sunset. During the week Venus moves towards the bright star Spica. On the 14th and 15th Venus is close to the crescent Moon.



Whole sky view of the evening sky on Tuesday August 14 as seen from Adelaide at 19:09 ACST (90 minutes after sunset).  Four bright planets and the crescent Moon are visible in the evening sky.




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


Evening sky on Saturday August 11 looking North  as seen from Adelaide at 19:07 ACST (90 minutes after sunset). Jupiter is well above the horizon, close to the bright star alpha Librae.

The inset is a simulated telescopic view of Jupiter and its moons at 19:07 ACST (90 minutes after sunset) on the 13th, Europa is just finishing a transit. Io will undergo transit shortly after. Then their respective shadow transits will start. Jupiter is  shown as seen with a 5mm telescopic eyepiece.

Similar views will be seen throughout Australia 90 minutes after sunset (click to embiggen).

Evening sky on Saturday August 11 looking east  as seen from Adelaide at 19:07 ACST (90 minutes after sunset). Saturn and Mars are clearly visible. The insets are simulated telescopic views of Saturn and Mars as seen with a 5mm telescopic eyepiece.

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

 Venus  is  readily visible above the horizon in the early evening.  It is bright enough to be visible from just on sunset and to well past 90 minutes after sunset at full dark, when it is two and a half hand-spans above the horizon.  During the week Venus moves towards the bright star Spica. On the 14th and 15th Venus is close to the crescent Moon.

Mercury is lost in the twilight and will reappear in the morning skies later in the month.

Jupiter  is high in the early evening sky above the northern horizon. It was at Opposition on the May 9th, and is still visible most of the night. It is  a good telescopic object in the mid to late evening and is highest around 17:47 local time (just before full dark). There are some good Jovian Moon events this week. This week Jupiter is coming closer to the bright star alpha Librae (Zubenelgenubi).

 Mars is in Capricornius and is readily seen in the evening. Mars was at opposition last month on July 27th,  when it was biggest and brightest as seen from Earth. This was the best opposition since 2003. However Mars will remain bright and large in even small telescopes for some time. In a telescope you may see a few features as the huge dust storm sweeping the planet continues to subside.  A guide to observing Mars at the time is at my Mars Opposition page.

Saturn is climbing higher the evening sky, and is now a good telescopic object in the mid to late evening sky. It was at opposition, when Saturn is biggest and brightest as seen from Earth, on June the 27th. It is within binocular range of  the Trifid and Lagoon nebulae.

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/

Labels: weekly sky

Perseid radiant as seen from Darwin at 5:00 am local time, August the 13th, looking north. Click to embiggen.	Perseid radiant as seen from Brisbane at 5:00 am local time, August the 13th, looking north. Note how much lower the radiant is than in Darwin.

You may have seen Facebook posts (or twitter notifications ) saying that on August 12/13 there will be a meteor shower that will be the brightest ever seen by mankind with Thousands of shooting stars. Well nope. This is the Perseid meteor shower, and though a reliable and good northern hemisphere shower, and hundreds of meteors may be seen under the very best condition, this year the rates will be around usual, nice but not spectacular.

The Perseid Meteor Shower runs from July 17–August 24, and peaks in the early morning between Saturday August 12 - Sunday August 14 AEST. The midpoint is August 12, 20h UT to 13, 08 h UT (6 am on the 13th AEST-6pm AEST on the 13th).  See the International Meteor Calendar for 2018 for further details.

Despite this being a quite reasonable meteor shower in the northern hemisphere, for most of Australia the radiant is below the horizon, and only the very occasional meteor will be seen shooting up from the northern horizon. Only observers in northern Australia (at the latitude of Brisbane or further north) will have decent rates.

This is a good year, while the peak occurs after sunrise in Australia, it still occurs reasonably close to radiant maximum height, this years peak is about usual (with a ZHR of 110 meteors per hour predicted) the Moon is near new and will not interfere.

However, these ZHR predictions are ideal rates for sites with the meteor radiant directly overhead, under the darkest possible skies with nothing obscuring the sky. From Australia, we will see much lower rates than these ideal ones. Anyone south of Brisbane will see only the occasional meteor, say maybe one or two per hour (or less), the further north of Brisbane you are, the more meteors you will see.

You can check predictions for your local area at the NASA meteor flux estimator (choose 7 Perseids and 12-13 or 13-14 August 2018). 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.

Labels: Meteors, Perseid, unaided eye

Entire sequence of the eclipse stacked and aligned in GIMP, starting every 5 minutes until totality and then every 10 minutes until the Moon finally disappeared behind the roof tops (4:06 am.-6:23 am) Sadly the later stages are made rubbish by whatever compression  GIMP uses, but you can see the beginning of the glow as maximum eclipse passes (totality ended at 6:44 am; click to embiggen).	Inital sequence of the eclipse up until the start of totality stacked and aligned in ImageJ, starting every 5 minutes until totality. I didn't do the full sequence as aligning moon images in ImageJ is a right pain, and they tend to get out of sequence. but the quality of the fully eclipsed images is much higher.

Here, as promised, are my animations of the total lunar eclipse of July 28. Because the motor drive on the telescope decided to stop working, I had to manually drive the scope, and the images were not aligned, so I had to align the images by hand. This is a pain in both GIMP and ImageJ (even though there are tools in both to do it they each have their own limitations.

But in the end it work out okay, mostly. not too happy with the way GIMP made the eclipsed images low res, but it does give you a feel for what it was like.

Labels: animation, astrophotography, eclipse, gimp, imageJ, Moon

Total Lunar Eclipse of 28 July, 4:06 am. Sony Xperia 1/2000th sec exposure ASA 400.	28 July, 4:25 am. Sony Xperia 1/2000th sec exposure ASA 400.
28 July, 4:51 am. Sony Xperia 1/8th sec exposure ASA 800. 10 minutes to totality.	28 July, 5:50 am. Sony Xperia 1/8th sec exposure ASA 12000. Pretty much maximum eclipse

My alarm went off a 3:30 am as planned. The sky was achingly clear, I had everything planned. Observing clothes out, lenses already set out, I had practised setting up the mobile phone on the mobile phone telescope adapter I had bought just for this.

As I got the scope out and set it up I could see the penumbral shadow creeping over the moon. The the motor drive wouldn't track! By the time I gave up and settled for imaging untracked shots a substantial divot had been taken out of the Moon (as  seen in the top left hand shot, which is the first image I got).

The Mobile phone adaptor worked like a dream. I took images at 5 minute intervals (more or less, depending on where I was making a cuppa or not) as I watched earth's shadow creep over. As the moon as more and more consumed by shadow, I started playing around with different exposure times and ASA values to try and bring out both the illuminated and eclipsed Moon. Taking images with the phone allowed me to send them to the internet in real time as well.

Then the last sliver of illuminated Moon vanished and we had totality...AANNND I had to move my carefully aligned scope. as the Moon went behind the roof.

"Super Blue Moon" Total Lunar eclipse of 1 February 1:12 am. Sony Xepria 1/500th sec exposure ASA 400. This is a perigee Moon	"Mini Moon" Total Lunar Eclipse of 28 July, 4:25 am. Sony Xepria 1/2000th sec exposure ASA 400. This is an apogee Moon. Note the clear difference in size between the two (same image scale and zoom factor)

Scope set up again I paused to take in the awesome burnished disk that was the Moon. The sky was dark again and the night hushed. The MiddleOne's friend who was staying over came out (he had accidentally left on his work alarm, both my kids stayed in bed even though I asked them to come out).

Then my firnd Steve and his son turned up.  I showed them the eclipsed Moon through the scope via the Mobile (makes it much easier to show people things). Ruddy Mars was a brilliant counterpoint to the copper Moon. Even though the Moon was eclipsed, its show  did not stop. As it headed into the central part of Earth's shadow it got darker still becoming a dark grey colour. Then as it moved out of the deepest Shadow the sky began to pale as twilight advanced.. AND I had to move my scope AGAIN as rooves interfered (should have set up in my third spot first).

The Moon and Mars at maximum totality 5:51 am 3x Zoom (Canon IXUS 15 sec, ASA 400)	The Moon and Mars aas twilight creeps in 6:16 am 3x Zoom(Canon IXUS 15 sec, ASA 400)

The others went off to their beds again and I took my camera and decamped to the beach for the the International Space Staiton Pass and the finale. Got down the end of the road and set up, the sky paled and the Moon faded as it headed towards the sea. Right on time the ISS appeared and began to glide above the eclipsed Moon, pale against the twilight sky but still visible, and Mars.

Unfortunately I had the exposure time too long for the conditions, so the Moon Mars and ISS are a bit washed out, so I had to do a quick exposure change during the ISS shots, so my ISS sequence isn't the best, but boy did it look great when I was watching it.

The International space station zooms over the Moon and Mars 6:42:38(Canon IXUS 5 sec, ASA 400)	The International space station zooms over the Moon and Mars 6:42:46 (Canon IXUS 5 sec, ASA 400)

And the the Earth's shadow finally slipped off the Moon, the pathc of Moon was still plae against the brightening sky but still brighter tha the eclipsed portion. Eveni=ually the waxin crescent slipped behind the marine layer, and my eclipse was over.

And totality ends. Sony Xepria 1/16th sec exposure ASA 800.

Then  I went home, packed up the scopes, had a quick look at others photos and went to bed (well, the sofa so I didn't disturb my Beloved Life Partner) for a quick snooze, the grand adventure finished.

Labels: astrophotography, eclipse, Mars, mobile Phone, Moon

Evening sky on Tuesday August 14 looking east  as seen from Adelaide at 19:09 ACST (90 minutes after sunset).  Venus and the crescent Moon are close. (The inset shows the telescopic view of Venus at this time, similar views will be seen Australia wide 90 minutes minutes after sunset).

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

The August edition of Southern Skywatch is now up.

This month still only 4 of the bright planets in the evening sky as  Mercury returns to the morning sky late in the month. Threr planets brighter than magnitude -2,  Venus , Jupiter and Mars are prominent in the evening sky and Saturn rises higher in the evening sky. Mars is just past Opposition.


Mercury is lost in the twilight and returns to the morning sky late in the month, but never rises much above the horizon.

Venus is close to the bright star Spica on the 31st. 

Jupiter is close to alpha Librae (Zubenelgenubi) at the beginning of the month, and is closest on the 15th-19th. Jupiter is close to the Moon on the 17th.

 Mars was at opposition on July the 27th, this is the best opposition since 2003. It is still a very good telescopic target. More details at my Mars opposition site. August 23, Moon and Mars close.

Saturn is within a binocular field of the the Trifid Nebula and Lagoon Nebula this month. August 21 Moon close to Saturn.

August 14-15, crescent Moon near Venus.

August 17; Moon close to Jupiter. August 21 Moon close to Saturn. August 23, Moon and Mars close.

August 11, Moon at Perigee; August 23, Moon at Apogee. 

Labels: southern skywatch

The Last Quarter Moon is Sunday, August 5.  Mercury is no longer visible in the evening sky but the remaining 4 bright unaided eye planets can be seen in the evening sky. Venus is high in the early evening sky. Jupiter is past opposition, but is still big and bright in telescopes. Mars and Saturn are visible in the evening skies. Mars is just past opposition but is still bright and  big in even small telescopes.

The Last Quarter Moon is Sunday, August 5.

Evening twilight sky on Saturday August 8 looking west as seen from Adelaide at 18:33 ACST (60 minutes after sunset). Venus is high above the horizon and close to the star beta Virginis. The inset shows  simulated telescopic views of Venus as seen with a 5mm telescopic eyepiece (compare with Jupiter, Saturn and Mars).

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

Brilliant Venus is now visible in the evening until well after full dark. Venus is visible to the unaided eye from sunset, easy to see 30-60 minutes after sunset and can viewed well after 90 minutes after sunset. During the week Venus moves towards the bright star Spica. On the 4th it passes close to the star Beta Virginis (Zavijava).

Evening sky on Saturday August 8 looking North  as seen from Adelaide at 19:03 ACST (90 minutes after sunset). Jupiter is well above the horizon, close to the bright star alpha Librae.

The inset is a simulated telescopic view of Jupiter and its moons at 22:49 ACST, Ganymede has just reappeared from eclipse and Europa has just reappeared from occultation. Io will undergo transit shortly after. Jupiter is  shown as seen with a 5mm telescopic eyepiece.

Similar views will be seen throughout Australia 90 minutes after sunset (click to embiggen).

Evening sky on Saturday August 8 looking east  as seen from Adelaide at 19:03 ACST (90 minutes after sunset). Saturn and Mars are clearly visible. The insets are simulated telescopic views of Saturn and Mars as seen with a 5mm telescopic eyepiece.

Similar views will be seen throughout Australia at the equivalent local time (90 minutes after sunset, click to embiggen).
 Venus  is  readily visible above the horizon in the early evening.  It is bright enough to be visible from just on sunset and to well past 90 minutes after sunset at full dark, when it is two and a half hand-spans above the horizon. During the week Venus moves towards the bright star Spica. On the 4th it passes close to the star Beta Virginis (Zavijava).

Mercury is lost in the twilight and will reapear in the morning skies later in the month.

Jupiter  is high the early evening sky. It was at Opposition on the May 9th, and is still visible most of the night. It is  a good telescopic object in the mid to late evening and is highest around 18:00 local time (just before full dark). There are some good Jovian Moon events this week. This week Jupiter is still close to the bright star alpha Librae (Zubenelgenubi).

 Mars is in Capricornius and is readily seen in the evening. Mars was at opposition last month on July 27th,  when it was biggest and brightest as seen from Earth. This was the best opposition since 2003. However Mars will remain bright and large in even small telescopes for some time. In a telescope you may see a few features as the huge dust storm sweeping the planet subsides.  A guide to observing Mars at the time is at my Mars Opposition page.

Saturn is climbing higher the evening sky, and is now a good telescopic object in the mid to late evening sky. It was at opposition, when Saturn is biggest and brightest as seen from Earth, on June the 27th. It is within binocular range of several attractive clusters and nebula. It is close to the bright globular cluster M22 and the pair are visible in binoculars and wide field telescope eyepieces.

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/

Labels: weekly sky