.comment-link {margin-left:.6em;}

Monday, July 31, 2017

 

Australian Perseid Meteor Shower - Morning August 13, 2017

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 best condition, this year the just bright waning Moon is in the sky above the meteor radiant, so rates will be lower than usual.

The Perseid Meteor Shower runs from July 17–August 24, and peaks in the early morning between Saturday August 12 - Sunday August 13 AEST. The midpoint is 20 H UT on the 12th (6 am AEST).  See the International Meteor Calendar for 2017 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 poor year, while the peak occurs after sunrise in Australia, it still occurs reasonably close to radiant maximum height and while this years peak is higher than usual (with a ZHR of 150 meteors per hour predicted) the bright waning Moon will substantially reduce the number of meteors you can see.

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 2017). 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.

People around the latitude of Darwin have the best chance of seeing meteors, possibly as many as one every 5 minutes at the peak (see table below). Next is places with the latitude of Cairns (around a meteor every 6 minutes), then with the latitude of Mackay (like Port Headland and Mt Isa), and the places with the latitude of Alice Springs (again,see table below).

To see the meteors, you will need to be up from around 3:00 am local time on the 12th, 13th or 14th (yes, a really horrible hour of the morning), with best views 4:00 am-5:30 am on the 13th. The meteor shower will be located due North, with the radiant just above the northern horizon (see charts above). Cloud cover predictions can be found at SkippySky.

When you get up, allow at least 5 minutes for your eyes to adjust, 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. 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 unsalubrious park for example).

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. (Here's some hints on dark adaptation of your eyes so you can see meteors better).

The following table show the predicted peak rates at around 5 am local time on the mornings of the 12th, 13 and 14th of August for a number of cities under dark sky conditions. Rates will be similar at the same latitude as these cities, and rates will be intermediate at spots between these cities.

TownMorning August 12Morning August 13Morning August 14
Alice Springs3 meteors/hr6 meteors/hr4 meteors/hr
Brisbane2 meteors/hr3 meteors/hr2 meteors/hr
Cairns5 meteors/hr10 meteors/hr7 meteors/hr
Darwin8 meteors/hr13 meteors/hr9 meteors/hr
Mackay4 meteors/hr7 meteors/hr5 meteors/hr

Rates on the morning of the 15th are similar to that of the 14th. Note, those of you who have Stellarium, in version 13 they have added meteor shower radiants (rates set in the planets dialogue, F4). However while the radiants are shown, the simulated meteors come from random points in the sky, not the radiants. 

Labels:


Saturday, July 29, 2017

 

How to see Bright Nova ASSN-17hx from Australia

Location of Galactic nova ASASSN-17hx as seen from Adelaide at midnight. It is just above gamma Scutum (indicated on the map.), between gamma Scut and V450 Scut. Click to embiggen

Galactic nova ASASSN-17hx has brightened remarkably since it was first seen at magnitude 12.5, it is now magnitude 8-9. It may have peaked, and observations are reguested to follow this bright nova.

The Nova is definitely bright enough to be seen in small telescopes, and may even be picked up in binoculars from dark sky locations.  Watching over the next few days will reveal if it brightens more or fades.

The nova is in Scutum between Gamma Sct (highlighted on chart which is suitable for binocular use)  and V50 Sct as indicated by the yellow star. click to embiggen.

It is  visible from the southern hemisphere and Australia. from astronomical twlight (and hour and a half after sunset to astronomical twight. It is higest and best for observation around 10 pm local time.

The Moon is setting around midnight so viewing and imaging is best after Moon set. However, over the coming days this means the nova will be closer to the horizon.

Black and white printable chart suitable for telescope use. Star magnitudes to 10 are indicated. The frame is the field of view of a 35 mm camera on a reflector scope. Click to embiggen and print.

The J2000 location of the NOVAis RA = 18:31:45.918, Dec = -14:18:55.57


Black and white printable chart suitable for binocular use (equivalent to the photorealistic chart above). Click to embiggen and print.

Labels:


 

Southern Delta Aquariid Meteor Shower 29-31 July, 2017

Evening sky looking east from Adelaide at 2 am local time on July 30th in South Australia. The cross marks the radiant  (the point where the meteors appear to originate from) of the Southern Delta Aquariids.  Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

The Southern Delta-Aquarids meteor shower runs from from 12 July to 23rd August, peaking on Sunday July the 30th. The number of meteors you will see depends on how high the radiant is above the horizon, and how dark your sky is. This shower is fairly faint, with the highest rate of around a meteor every 4 minutes (more detail below).

The ZHR  for Southern Delta Aquariids is 16 meteors per hour. The figure ZHR is zenithal hourly rate. This is the number of meteors that a single observer would see per hour if the shower's "point of origin", or radiant, were at the zenith and the sky were dark enough for 6.5-magnitude stars to be visible to the naked eye.

In practise, you will never see this many meteors as the radiant will be some distance below the zenith. Also, unless you are out deep in the countryside, the darkness will be less than ideal. As well, moonlight will significantly reduce rates. How many are you likely to see in reality? I discuss this further down, lets talk about when to see them first.

At 10 pm, face east, and look 4 hand spans and two finger widths above the horizon. One finger width right is the 4th magnitude star delta Aquarii. The radiant is just above this star. This meteor shower should be visible from 10.00 pm until dawn. The Moon will interfere until around mdinght, just after it sets.  The best rates will be at 2 am in the morning of the 30th. The radiant will be due north then, and close to the Zenith near the bright star Fomalhaut.

At 2 am people in the suburbs should see a meteor around once every 8 minutes, and in the country about once every 4 minutes at 2 am in the morning of the 30th.

When looking, be sure to let your eyes adjust for at least 5 minutes so your eyes can be properly adapted to the dark. Don't look directly at the radiant site, because the meteors will often start their "burn" some distance from it, but around a handspan up or to the side. Be patient, although you should see an average of a meteor every six to three minutes, a whole stretch of time can go by without a meteor, then a whole bunch turn up one after the other.

Make yourself comfortable, choose an observing site that has little to obstruct the eastern horizon, have a comfortable chair to sit in (a banana lounger is best), or blankets and pillows. Rug up against the cold.  A hot Thermos of something to drink and plenty of mosquito protection will complete your observing preparations. As well as meteors, keep an eye out for satellites (see Heavens Above for predictions from your site).

The sky will also be particularly beautiful, with the Milky Way stretching over the sky and constellation of Scorpius and Saturn gracing the western sky, And Venus rising in the eastern morning sky.

Use the NASA  meteor shower flux estimator for an estimate of what the shower will be like from your location. Unfortunately, both Chrome and Firefox have changed their security settings to prevent plugins from running, and the flux estimator only runs under Internet Explorer now. You need to choose 5 Southern Delta Aquariids and remember to set the date to 29-30 July or 30-31 July 2017

Cloud cover predictions can be found at SkippySky.

Labels:


Friday, July 28, 2017

 

Astrophiz Podcast 39 (shameless self promotion edition) is Out

Astrophiz Podcast 39 is out now.
In this episode I in my guise as Dr Ian 'Astroblog' Musgrave give an  (I hope) insightful approach to amateur astronomy, introduces basic equipment and cameras and iTelecope.net remote telescopes, tells I tell you what to look for in the evening and morning skies and in my Tangent, gives  more detail on occultations and how some asteroids can become comets.

I am someone very familiar to Astrophiz listeners. For the last 12 months I have  presented the ‘What’s Up Doc’ segment where he tells us what to look for in the night sky, astrophotography tips and in ‘Ian’s Tangent’ I give a deeper understanding of astronomical phenomena. Today I will do all that, but first ypu're going to find out more about this erstwhile producer of the fantastic ‘Astroblog’.

In the News: SKA update, the Voyager Missions, Non-Optical Telescopes and what to look forward to in our next couple of episodes.

Due to holidays and family stuff I missed out on updating you about Astrophiz 37 and 38, they are good too.

Labels:


Tuesday, July 25, 2017

 

The Sky This Week - Thursday July 27 to Thursday August 3

The First Quarter Moon is Monday, July 31. Mercury climbs above Regulus. Jupiter and the bright star Spica are nearby in the evening sky. The Moon forms a triangle with the pair on July 29. Saturn is visible all night in the heart of the Milky Way and is close to the Moon on August 3. Venus dominates the morning sky below the head of Taurus the Bull. The Southern Delta Aquariid meteor shower peaks on the 30th.

The First Quarter Moon is Monday, July 31.  The Moon is at apogee, furthest from the earth, on August 3rd.

Evening sky on Saturday July 29 looking west as seen from Adelaide at 18:29 ACST (60 minutes after sunset). Mercury is above the western horizon above Regulus.

Mercury climbs higher in the evening twilight sky. It is now readily visible above the western horizon half an hour after sunset, and is obvious well over 60 minutes after sunset. Mercury is climbing away from the bright star Regulus but the pair are still obviously close together.

Evening sky on Saturday July 29 looking north-west as seen from Adelaide at 18:59 ACST  (90 minutes after sunset). Jupiter is above the horizon between the bright star Spica and the relatively bright star Porrima. The waxing Moon forms a triangle with Spica and Jupiter. The inset shows the telescopic view of Jupiter on Saturday July 22 at 18:55 ACST .

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

Jupiter is rising before sunset and is now high above the northern-western horizon in the early evening at full dark. It is in between the bright star Spica, the brightest star in the constellation of Virgo, and the relatively bright star Porrima. Jupiter is now almost between Porrima and Spica. The waxing Moon forms a triangle with Spica and Jupiter on the 29th.

Opposition, when Jupiter is biggest and brightest as seen from Earth, was on April the 8th. Jupiter is rising before the sun sets and is visible until just before midnight. Jupiter is a good telescopic target from astronomical twilight on, and the dance of its Moons is visible even in binoculars. The following Jupiter events are in AEST.


Thu 27 Jul 18:42 GRS: Crosses Central Meridian 
Thu 27 Jul 21:53 Eur: Reappears from Eclipse 
Sat 29 Jul 20:21 GRS: Crosses Central Meridian 
Mon 31 Jul 17:51 Gan: Transit Ends 
Mon 31 Jul 20:16 Gan: Shadow Transit Begins        S 
Mon 31 Jul 22:00 GRS: Crosses Central Meridian 
Mon 31 Jul 22:24 Gan: Shadow Transit Ends 
Tue  1 Aug 17:51   GRS: Crosses Central Meridian
Tue  1 Aug 20:46   Io : Transit Begins               T
Tue  1 Aug 21:57   Io : Shadow Transit Begins        ST
Tue  1 Aug 22:58   Io : Transit Ends                 S
Wed  2 Aug 18:05   Io : Disappears into Occultation  
Wed  2 Aug 21:27   Io : Reappears from Eclipse       
Thu  3 Aug 18:36   Io : Shadow Transit Ends          
Thu  3 Aug 19:31   GRS: Crosses Central Meridian
Thu  3 Aug 19:45   Eur: Disappears into Occultation 
 

Evening sky on Thursday August 3 looking north as seen from Adelaide at 20:50 ACST, when Saturn is at its highest. Saturn is almost overhead high above the northern horizon. The Moon is just below Saturn.

The inset shows the telescopic view of Saturn at this time. Similar views will be seen elsewhere in Australia at the equivalent local time. (click to embiggen).

Saturn was  at opposition on the 15th, when it was biggest and brightest in the sky as seen from earth. Saturn is visible all night long. Saturn is a good telescopic target from 9 pm on. It is poised above the dark rifts in the Milky Way and is in a good area for binocular hunting. It continues to climb into the evening skies as the week progresses.  Saturn's rings are visible even in small telescopes and are always good to view.

The constellation of Scorpio is a good guide to locating Saturn. The distinctive curl of Scorpio is easy to see above the north-eastern to northern horizon, locate the bright red star, Antares, and the look below that towards the horizon, the next bright object is Saturn.

Morning sky on Saturday July 29 looking east as seen from Adelaide at 6:19 ACST (60 minutes before sunrise). Venus is dazzling below the bright star Aldebaran and forms a triangle with Aldebaran and Betelguese. The inset shows the telescopic view of Venus at this time.

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

Venus  is lowering in the morning sky and is visible in telescopes as a "Gibbous Moon". At the start of the Week Venus is below the head of  Taurus the Bull and  the bright star Aldebaran. by mid-week it forms the tip of the second horn of the Bull, and forms a triangle with Aldebaran and Beteguese.

 Mars is lost in the twilight.


Evening sky looking east from Adelaide at 2 am local time on July 30th in South Australia. The cross marks the radiant  (the point where the meteors appear to originate from) of the Southern Delta Aquariids.  Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

The Southern Delta-Aquarids meteor shower runs from from 12 July to 23rd August, peaking on Sunday July the 30th. The number of meteors you will see depends on how high the radiant is above the horizon, and how dark your sky is. This shower is fairly faint, with the highest rate of around a meteor every 4 minutes.

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:


Tuesday, July 18, 2017

 

The Sky This Week - Thursday July 20 to Thursday July 27

The New Moon is Sunday, July 23. Mercury rendezvous with Regulus and the thin crescent Moon on the 25th. Jupiter and the bright star Spica are nearby in the evening sky. Saturn is visible all night in the heart of the Milky Way. Venus dominates the morning sky below the head of Taurus the Bull. The crescent Moon is below Venus on the 21st.

The New Moon is Sunday, July 23. The Moon is at Perigee, closest to the earth, on the 22nd.

Evening sky on Tuesday July 25 looking west as seen from Adelaide at 18:25 ACST (60 minutes after sunset). Mercury is above the western horizon near Regulus and the thin crescent Moon.

Mercury climbs higher in the evening twilight sky. It is now readily visible above the western horizon half an hour after sunset, and is obvious at least 60 minutes after sunset. Mercury is climbing towards the bright star Regulus. On the 25th and 26th Mercury and Regulus will be less than a finger-width apart, on the 25t they are joined by the thin crescent Moon. 

Evening sky on Saturday July 22 looking north-west as seen from Adelaide at 18:55 ACST  (90 minutes after sunset). Jupiter is above the horizon between the bright star Spica and the relatively bright star Porrima. The inset shows the telescopic view of Jupiter on Saturday July 22 at 18:55 ACST .

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

Jupiter is rising before sunset and is now high above the northern-western horizon in the early evening at full dark. It is in between the bright star Spica, the brightest star in the constellation of Virgo, and the relatively bright star Porrima. Jupiter is now closer to Porrima than Spica.

Opposition, when Jupiter is biggest and brightest as seen from Earth, was on April the 8th. Jupiter is rising before the sun sets and is visible until just before midnight. Jupiter is a good telescopic target from astronomical twilight on, and the dance of its Moons is visible even in binoculars. The following Jupiter events are in AEST.


Thu 20 Jul 17:53 GRS: Crosses Central Meridian 
Thu 20 Jul 19:19 Eur: Reappears from Eclipse 
Thu 20 Jul 21:17 Gan: Disappears into Occultation 
Tue 20 Jun 22:57 GRS: Crosses Central Meridian 
Fri 21 Jul 23:40 GRS: Crosses Central Meridian 
Sat 22 Jul 19:32 GRS: Crosses Central Meridian 
Mon 24 Jul 18:26 Gan: Shadow Transit Ends 
Mon 24 Jul 21:11 GRS: Crosses Central Meridian 
Mon 24 Jul 21:37 Io : Disappears into Occultation 
Tue 25 Jul 18:49 Io : Transit Begins               T 
Tue 25 Jul 20:02 Io : Shadow Transit Begins        ST 
Tue 25 Jul 21:01 Io : Transit Ends                 S 
Tue 25 Jul 22:13 Io : Shadow Transit Ends 
Tue 25 Jul 22:39 Eur: Transit Begins               T 
Wed 26 Jul 19:32 Io : Reappears from Eclipse 
Wed 26 Jul 22:50 GRS: Crosses Central Meridian 
Thu 27 Jul 18:42 GRS: Crosses Central Meridian 
Thu 27 Jul 21:53 Eur: Reappears from Eclipse 
 

Evening sky on Saturday July 15 looking north as seen from Adelaide at 21:40 ACST, when Saturn is at its highest. Saturn is almost overhead high above the northern horizon.

The inset shows the telescopic view of Saturn at this time. Similar views will be seen elsewhere in Australia at the equivalent local time. (click to embiggen).

Saturn was  at opposition on the 15th, when it was biggest and brightest in the sky as seen from earth. Saturn is visible all night long. Saturn is a good telescopic target from 9 pm on. It is poised above the dark rifts in the Milky Way and is in a good area for binocular hunting. It continues to climb into the evening skies as the week progresses.  Saturn's rings are visible even in small telescopes and are always good to view.

The constellation of Scorpio is a good guide to locating Saturn. The distinctive curl of Scorpio is easy to see above the north-eastern to northern horizon, locate the bright red star, Antares, and the look below that towards the horizon, the next bright object is Saturn.

Morning sky on Friday July 21 looking east as seen from Adelaide at 6:19 ACST (60 minutes before sunrise). Venus is dazzling below the bright star Aldebaran and above  the crescent Moon. The inset shows the telescopic view of Venus at this time.

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

Venus  is lowering in the morning sky and is visible in telescopes as a "Gibbous Moon". At the start of the Week Venus is below the head of  Tarus the Bull and  the bright star Aldebaran. The Crescent Moon is below Venus on the 21st forming a line with  Aldebaran .

 Mars is lost in the twilight.

Printable PDF maps of the Eastern sky at 10 pm AEST, Western sky at 10 pm AEST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.

Here is the near-real time satellite view of the clouds (day and night) http://satview.bom.gov.au/

Labels:


Sunday, July 16, 2017

 

Geomagnetic warning and Aurora Watch (16-17 July)

The Australian Space Weather Service (SWS) has now  issued a Geomagnetic Alert an Aurora Watch for possible aurora for 16-17 July (UT) due to an impact from a coronal Mass Ejection. This is expected to arrive late in the UT day on the 16th (which is the morning of the 17th Australian time).

The Space Weather Prediction Service has predicted a G1-G2 storm on July 16 UT (with most of the action on the morning f the 17th, probably extending into the evening of the 18th AEST if we are lucky). If these geomagnetic events occur and result in aurora they could be seen from Tasmania and Southern Victoria, weather permitting. The Moon is waning, and present in the early morning so will only modestly interfere with morning aurora. Be patient, as the activity may rise and fall of the magnetic polarity of the wind may fluctuate significantly.

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 consistently over the last few aurora, as well as bright proton arcs and "picket fences".

Here is the near-real time satellite view of the clouds http://satview.bom.gov.au/
Cloud cover predictions can be found at SkippySky.  

A new aurora camera is being installed at Campania, Tasmania. A live feed of the images from this camera is expected to be operational by the end of July 2017 .

SUBJ: SWS GEOMAGNETIC DISTURBANCE WARNING 17/34
ISSUED AT 0010UT/15 JULY 2017
BY THE AUSTRALIAN SPACE FORECAST CENTRE.

Geomagnetic conditions may rise to minor storm levels late on
16 Jul. Geomagnetic activity is expected to remain enhanced to
active to minor storm levels with the possibility of major storm
periods on 17 Jul due to CME effects.

INCREASED GEOMAGNETIC ACTIVITY EXPECTED
DUE TO CORONAL MASS EJECTION
FROM 16-17 JULY 2017
_____________________________________________________________

GEOMAGNETIC ACTIVITY FORECAST
16 Jul:  Active to Minor Storm
17 Jul:  Active to Minor Storm, some major storm periods possible.
_____________________________________________________________

SUBJ: SWS AURORA WATCH
ISSUED AT 0230 UT ON 15 Jul 2017 by Space Weather Services
FROM THE AUSTRALIAN SPACE FORECAST CENTRE

A Coronal Mass Ejection(CME) is anticipated to impact the Earth late
in the UT day of 16 July (Monday morning AEST). Aurora sightings
possible for Southernmost Australian regions should the CME arrive
earlier than anticipated. Aurora alerts will follow if significant
geomagnetic activity actually occurs.

Labels:


Wednesday, July 12, 2017

 

Yet Another good Week for ISS passes, (12 July - 20 July)

The ISS passes below Jupiter, as seen from Melbourne on the evening of Monday 17 July at 19:05 AEST. Simulated in Stellarium (the ISS will actually be a bright dot), click to embiggen.The ISS passes below Saturn, as seen from Adelaide on the evening of Monday 17 July at 18:35 ACST. Simulated in Stellarium (the ISS will actually be a bright dot), click to embiggen.The ISS passes below Saturn, as seen from Perth on the evening of  Monday 17 July at 18:36 AWST. Simulated in Stellarium (the ISS will actually be a bright dot), click to embiggen.
All sky chart showing local times from Heavens Above for Monday 17 July for Melbourne.All sky chart showing local  times from Heavens Above for Monday 17 Julyy for Adelaide.All sky chart showing local times from Heavens Above for Monday 17 July for Perth.

Starting tonight there are a series of bright evening passes of the International Space Station lasting around eight days. Some are low to the horizon, some rapidly enter earth's shadow, but for many places in Australia this series has the ISS gliding either close to Jupiter, Saturn or a series of bright stars (except Darwin, which only gets three bright evening passes). For some passes there are also bright iridium flares close by (eg July 19 from Adelaide,check the prediction sites for details).
 
The ISS passes extremely close to the bright stars Canopus and Arcturus during some of these passes (check your local predictions)

Most of the major cites see the ISS pass close to either Saturn of Jupiter at the following days and times:
Adelaide 17th July 18:34 ACST (Saturn) 18:32 Canopus, 19th July Jupiter (18:26) Arcturus (18:27)
Brisbane 18th July 18:16 AEST (Saturn) 18:12 Canopus, 20th July Jupiter (18:07) Arcturus (18:08)
Sydney 16th July 18:22 AEST (Saturn) 18:19 Canopus, 18th July Jupiter (18:14) Arcturus (-)
Melbourne 16th July 18:21 AEST (Saturn) 18:18 Canopus, 17th July Jupiter (19:05) Arcturus (19:06)
Perth 17th July 18:36 AWST (Saturn) 18:30 Canopus, 19th July Jupiter (18:29) Arcturus (18:36)
Hobart 17th July 17:25 AEST (Saturn) 18:23 Canopus, 18th July Jupiter (18:12) Arcturus (18:13)
 
When and what you will see is VERY location dependent, so you need to use either Heavens Above or CalSky to get site specific predictions for your location, a small difference in location can mean the difference between the ISS passing over a star or missing it completely.
 
Start looking several minutes before the pass is going to start to get yourself oriented and your eyes dark adapted. Be patient, there may be slight differences in the time of the ISS appearing due to orbit changes not picked up by the predictions. Use the most recent prediction for your site.

Labels: , , , ,


 

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

The Last Quarter Moon is Monday, July 17. Mercury climbs higher in the evening sky. Jupiter and the bright star Spica are nearby in the evening sky. Saturn is visible all night in the heart of the Milky Way. Venus dominates the morning sky between the Pleiades and the Hyades clusters and continues towards the bright star Aldebaran, forming a second "eye" for Taurus the Bull on the 13th. The crescent Moon is in the Hyades above Venus on the 20th. The ISS returns to evening skies.

The Last Quarter Moon is Monday, July 17.

Evening sky on Saturday July 15 looking west as seen from Adelaide at 18:22 ACST (60 minutes after sunset). Mercury is above the western horizon climbing towards Regulus.

Mercury climbs higher in the evening twilight sky. It is now readily visible above the western horizon half an hour after sunset, and is obvious at lest 60 minutes after sunset.




Evening sky on Saturday July 15 looking north-west as seen from Adelaide at 18:52 ACST  (90 minutes after sunset). Jupiter is above the horizon between the bright star Spica and the relatively bright star Porrima. The inset shows the telescopic view of Jupiter on Sunday July 16 at 22:23 ACST  as Io and its shadow transits Jupiter.

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

Jupiter is rising before sunset and is now high above the northern-western horizon in the early evening at full dark. It is in between the bright star Spica, the brightest star in the constellation of Virgo, and the relatively bright star Porrima. Jupiter is now closer to Porrima than Spica.

Opposition, when Jupiter is biggest and brightest as seen from Earth, was on April the 8th. Jupiter is rising before the sun sets and is visible until just after midnight. Jupiter is a good telescopic target from astronomical twilight on, and the dance of its Moons is visible even in binoculars. The following Jupiter events are in AEST.


Thu 13 Jul 19:46 Gan: Reappears from Occultation 
Thu 13 Jul 22:31 Gan: Disappears into Eclipse 
Fri 14 Jul 22:52 GRS: Crosses Central Meridian 
Sat 15 Jul 18:43 GRS: Crosses Central Meridian 
Sun 16 Jul 22:23 Io : Transit Begins               T 
Sun 16 Jul 23:39 Io : Shadow Transit Begins        ST 
Mon 17 Jul 19:40 Io : Disappears into Occultation 
Mon 17 Jul 20:22 GRS: Crosses Central Meridian 
Mon 17 Jul 23:08 Io : Reappears from Eclipse 
Tue 18 Jul 18:07 Io : Shadow Transit Begins        ST 
Tue 18 Jul 19:05 Io : Transit Ends                 S 
Tue 18 Jul 19:58 Eur: Transit Begins               ST 
Tue 18 Jul 20:18 Io : Shadow Transit Ends          T 
Tue 18 Jul 22:29 Eur: Transit Ends 
Tue 18 Jul 22:35 Eur: Shadow Transit Begins        S 
Wed 19 Jul 17:37 Io : Reappears from Eclipse 
Wed 19 Jul 22:01 GRS: Crosses Central Meridian 
Thu 20 Jul 17:53 GRS: Crosses Central Meridian 
Thu 20 Jul 19:19 Eur: Reappears from Eclipse 
Thu 20 Jul 21:17 Gan: Disappears into Occultation  
 

Evening sky on Saturday July 15 looking north as seen from Adelaide at 22:00 ACST, when Saturn is at its highest. Saturn is almost overhead high above the northern horizon.

The inset shows the telescopic view of Saturn at this time. Similar views will be seen elsewhere in Australia at the equivalent local time. (click to embiggen).

Saturn was  at opposition on the 15th, when it was biggest and brightest in the sky as seen from earth. Saturn is visible all night long. Saturn is a good telescopic target from 9 pm on. It is poised above the dark rifts in the Milky Way and is in a good area for binocular hunting. It continues to climb into the evening skies as the week progresses.  Saturn's rings are visible even in small telescopes and are always good to view.

The constellation of Scorpio is a good guide to locating Saturn. The distinctive curl of Scorpio is easy to see above the north-eastern to northern horizon, locate the bright red star, Antares, and the look below that towards the horizon, the next bright object is Saturn.

Morning sky on Thursday July 20 looking east as seen from Adelaide at 6:22 ACST (60 minutes before sunrise). Venus is dazzling below the bright star Aldebaran and the crescent Moon. The inset shows the telescopic view of Venus at this time.

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

Venus  climbs higher in the morning sky and is visible in telescopes as a "Gibbous Moon".  at the start of the Week Venus Forms a second eye for Tarus the Bull with the bright star Aldebaran. It then moves below Hildebrand. The Crescent Moon is near Aldebaran and above Venus on the 20th.

The evening sky facing East at 18:35 pm ACST on Monday 17 June as seen from Adelaide. Adelaide gets to see the ISS pass next to Saturn. This week sees a series of bright International space station passes in the evening visible from most parts of Australia. More details here. When and what you will see is VERY location dependent, so you need to use either Heavens Above or CalSky to get site specific predictions for your location.






 Mars is lost in the twilight.

Printable PDF maps of the Eastern sky at 10 pm AEST, Western sky at 10 pm AEST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.

Here is the near-real time satellite view of the clouds (day and night) http://satview.bom.gov.au/

Labels:


Friday, July 07, 2017

 

Geomagnetic warning and Aurora Watch (8-9 July)

The Australian Space Weather Service (SWS) has now  issued a Geomagnetic Alert an Aurora Watch for possible aurora for 8-9 July (UT) due to solar wind from a coronal hole. This is expected to arrive late in the UT day on the 8th (which is the morning of the 9th Australian time). The Space Weather Prediction Service has Predicted a G1 storm on July 9 UT. If these geomagnetic events occur and result in aurora they could be seen from Tasmania and Southern Victoria, weather permitting.

However, the Moon is nearly full, so will significantly interfere. Be patient, as the activity may rise and fall of the magnetic polarity of the wind may fluctuate significantly.

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 consistently over the last few aurora, as well as bright proton arcs and "picket fences".

Here is the near-real time satellite view of the clouds http://satview.bom.gov.au/
Cloud cover predictions can be found at SkippySky.  

A new aurora camera is being installed at Campania, Tasmania. A live feed of the images from this camera is expected to be operational by the end of July 2017 .

SUBJ: SWS GEOMAGNETIC DISTURBANCE WARNING 17/33
ISSUED AT 0057UT/07 JULY 2017
BY THE AUSTRALIAN SPACE FORECAST CENTRE.

Expect an increase in geomagnetic activity late on UT day, 08
July due to influence of geoeffective coronal hole.

INCREASED GEOMAGNETIC ACTIVITY EXPECTED
DUE TO CORONAL HOLE HIGH SPEED WIND STREAM
FROM 08-09 JULY 2017
_____________________________________________________________

GEOMAGNETIC ACTIVITY FORECAST
08 Jul:  Quiet to Active isolated cases of Minor Storm levels at higher
latitudes
09 Jul:  Unsettled

_____________________________________________________________

SUBJ: SWS AURORA WATCH
ISSUED AT 0130 UT ON 07 Jul 2017 by Space Weather Services
FROM THE AUSTRALIAN SPACE FORECAST CENTRE

Effects of a coronal hole are expected to impact the Earth within the
next 48 hours, possibly resulting in geomagnetic activity and visible
auroras during local nighttime hours at Tasmania latitudes. Aurora
alerts will follow if significant geomagnetic activity actually
occurs.

Labels:


Tuesday, July 04, 2017

 

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

The Full Moon is Sunday, July 9. Mars is lost in the twilight. Mercury climbs higher in the evening sky. Jupiter and the bright star Spica are nearby in the evening sky. Saturn is visible all night in the heart of the Milky Way. The Moon is close to Saturn on the 7th. Venus dominates the morning sky between the Pleiades and the Hyades clusters and continues towards the bright star Aldebaran.

The Full Moon is Sunday, July 9.

Evening sky on Saturday July 8 looking west as seen from Adelaide at 18:00 ACST (45 minutes after sunset). Mercury is low above the western horizon.

Mercury climbs higher in the evening twilight sky. It is now readily visible above the western horizon half an hour after sunset, and is obvious at last 45 minutes after sunset if you have a reasonably level unobstructed horizon.




Evening sky on Saturday July 8 looking north as seen from Adelaide at 18:05 ACST (when Jupiter is highest in the sky). Jupiter is above the horizon between the bright star Spica and the relatively bright star Porrima. Jupiter is now closer to Porrima than Spica. The inset shows the telescopic view of Jupiter on Sunday July 9 at 21:42 ACST  as Io and its shadow transits Jupiter and europa is just about to be occulted..

Similar views will be seen elsewhere in Australia at the equivalent local time. (click to embiggen).

Jupiter is rising before sunset and is now high above the northern horizon in the early evening ju     before full dark. It is in between the bright star Spica, the brightest star in the constellation of Virgo, and the relatively bright star Porrima. Jupiter is now closer to Porrima than Spica.

Opposition, when Jupiter is biggest and brightest as seen from Earth, was on April the 8th. Jupiter is rising before the sun sets and is visible until jussssst . Jupiter is a good telescopic target from astronomical twilight on, and the dance of its Moons is visible even in binoculars. The following Jupiter events are in AEST.


Thu 6 Jul 18:31 Gan: Disappears into Eclipse 
Thu 6 Jul 20:43 Gan: Reappears from Eclipse 
Fri 7 Jul 22:03 GRS: Crosses Central Meridian 
Sat 8 Jul 17:55 GRS: Crosses Central Meridian 
Sat 8 Jul 23:15 Io : Disappears into Occultation 
Sun 9 Jul 20:28 Io : Transit Begins               T 
Sun 9 Jul 21:44 Io : Shadow Transit Begins        ST 
Sun 9 Jul 22:31 Eur: Disappears into Occultation  ST 
Sun 9 Jul 22:40 Io : Transit Ends                 S 
Sun 9 Jul 23:42 GRS: Crosses Central Meridian 
Sun 9 Jul 23:55 Io : Shadow Transit Ends 
Mon 10 Jul 17:44 Io : Disappears into Occultation 
Mon 10 Jul 19:34 GRS: Crosses Central Meridian 
Mon 10 Jul 21:13 Io : Reappears from Eclipse 
Tue 11 Jul 18:23 Io : Shadow Transit Ends          T 
Tue 11 Jul 19:49 Eur: Transit Ends 
Tue 11 Jul 19:57 Eur: Shadow Transit Begins        S 
Tue 11 Jul 22:21 Eur: Shadow Transit Ends 
Wed 12 Jul 21:13 GRS: Crosses Central Meridian 
Thu 13 Jul 19:46 Gan: Reappears from Occultation 
Thu 13 Jul 22:31 Gan: Disappears into Eclipse  
 

Evening sky on Friday July 7 looking east as seen from Adelaide at 18:44 ACST, an hour and a half after sunset. Saturn is reasonably high above the horizon and the waxing Moon is just below Saturn.

The inset shows the telescopic view of Saturn at this time. Similar views will be seen elsewhere in Australia at the equivalent local time, an hour and a half after sunset. (click to embiggen).

Saturn was  at opposition on the 15th, when it was biggest and brightest in the sky as seen from earth. Saturn is visible all night long. Saturn is a good telescopic target from 9 pm on. It is poised above the dark rifts in the Milky Way and is in a good area for binocular hunting. It continues to climb into the evening skies as the week progresses.  Saturn's rings are visible even in small telescopes and are always good to view. On the 7th the waxing Moon is just below Saturn.

The constellation of Scorpio is a good guide to locating Saturn. The distinctive curl of Scorpio is easy to see above the north-eastern horizon, locate the bright red star, Antares, and the look below that towards the horizon, the next bright object is Saturn.

Morning sky on Saturday July 8 looking east as seen from Adelaide at 6:24 ACST (60 minutes before sunrise). Venus is dazzling and moves towards the bright star Aldebaran during the week, Passing between the Pleiads and Hyades clusters. The inset shows the telescopic view of Venus at this time.

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

Venus  climbs higher in the morning sky and is visible in telescopes as a "half-Moon".  During the Week Venus moves towards the bright star Aldebaran passing between the Pleiades and Hyades clusters.

 Mars is lost in the twilight.

Printable PDF maps of the Eastern sky at 10 pm AEST, Western sky at 10 pm AEST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.

Here is the near-real time satellite view of the clouds (day and night) http://satview.bom.gov.au/

Labels:


Saturday, July 01, 2017

 

The ISS pass on June 30, 2017

The ISS passing just above Canopus on 30 June, 2017. The ISS was around magnitude -2.4. Stack of 9 images in Deep Sky Stacker (one frames was dropped buring stacking, 5 second exposures 400 ASA with an ageing Canon IXUS)Animation of all 10 images

I missed the more spectacular June 29 pass due to clouds and rain. Still a very nice pass through a nice piece of sky. It looks clear for tonight, which will be a bright Pass just below the Southern Cross, and hopefully Monday, where the ISS will almost pas on top of Sirius then just below Canopus.

Labels: , ,


This page is powered by Blogger. Isn't yours?