Astroblog

Evening sky looking east from Adelaide at 11 pm local time in South Australia on the 30th. The starburst 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).	Evening sky looking east from Adelaide at 2:30 am local time on July 31st in South Australia. The starburst 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 Saturday night/ Sunday morning July the 30th-31st. 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 25 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 11 pm, face east, and look around 4 hand spans above the horizon. Jupiter is obvious as the brightest object above the horizon. The next brightest above it is Saturn. The radiant is between Jupiter and Satirn, closer to Saturn. This meteor shower should be visible from 10.00 pm until dawn. The best rates will be at 2:30 am on the evenings/mornings of the 29/30th and 30th/31st.

At 2:30 am people in the suburbs should see a meteor around once every 10 minutes, and in the country about once every 4 minutes at 2:30 am in the mornings of the 30th and 31st.

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 hand-span up or to the side. Be patient, although you should see an average of a meteor every six to four 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, Jupiter and Saturn gracing the eastern-northern 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. 

Labels: Meteors, unaided eye

# posted by Ian Musgrave @ 4:54 pm 2 comments

The New Moon is Friday, July 29. Four bright classical planets in a line in the morning sky, Saturn, Jupiter, Mars, and Venus.  Jupiter enters the evening sky below Saturn. Mercury is close to the thin crescent moon on July 30. The Southern Delta Aquariid meteor shower reaches its maximum on the late evening of the 30th, and early morning 31st. Mars is within binocular range of Uranus and is closest on August 2.

The New Moon is Friday, July 29. 

The insets are the telescopic views of Venus and Mars at the same magnification at this time.

Similar views will be seen from the rest of Australia at the equivalent local time (click to embiggen). 

Saturn forms a triangle with delta and gamma Capricornii, and Jupiter is just above the horizon.

The Southern Delta Aqauriid meteor shower peaks on the evening of the 30th, Morning 31st. The radiant is between Saturn and Jupiter. You can start viewing the shower any time after 10 pm local time, but the best rates are when the radiant is highest above the northern horizon: from 11 pm to 3 am.

The insets are the telescopic views of Saturn and Jupiter at the same magnification at this time.

Similar views will be seen from the rest of Australia at the equivalent local time. 

Mercury and the thin crescent Moon are visible low on the horizon, you may need binoculars to see Mercury.

Similar views will be seen from the rest of Australia at the equivalent local time (30 minutes after sunset).

 

Whole sky on Saturday, July 30, 19:00 ACST, 90 minutes after sunset (click to embiggen). The Milky Way stretches across the mid-sky and the centre of the galaxy is coming into view. 

Scorpius is prominent above the northern horizon with the teapot of Sagittarius below. From the Sting of the Scorpion through the teapot there is a wealth of binocular objects to discover.

Between the bright star Canopus and the Southern Cross are another wealth of binocular objects to discover. 

 

  

 Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset). 

 

Mercury is visible above the western horizon low in the twilight next week. It is close to the thin crescent Moon on the 30th.

Venus is lowering in the morning twilight. 

Mars forms a line with Saturn, Jupiter, and Venus (and Uranus and Neptune). 

Jupiter climbs higher in the morning twilight below Saturn and above Mars. Jupiter enters the evening sky low above the horizon.

Saturn climbs away from Mars, Jupiter, and Venus. Saturn forms a triangle with delta and gamma Capricornii.

 

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.


 

Star Map via Virtual sky. Use your mouse to scroll around and press 8 when your pointer is in the map to set to the current time.

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

# posted by Ian Musgrave @ 1:23 am 0 comments

The Last Quarter Moon is Thursday July 21. Four bright classical planets in a line in the morning sky, Saturn, Jupiter, Mars and Venus. The waning Moon is very close to Mars on the 22nd. The crescent Moon is between the Hyades and Pleiades on the 24th and the crescent Moon is close to Venus on the 26th/27th. Jupiter enters the evening sky.

The Last Quarter Moon is Thursday, July 21. The Moon is at apogee, when it is furthest from the Earth, on the 26th.

 Morning sky on Friday July 22 as seen from Adelaide at 03:00 ACST. 

The waning Moon is close to Mars (the pair will still be seen together until close to civil twilight, 30 minutes before sunrise, but the distance between the Moon and Mars increases as the morning goes on.

The insets is the binocular view of Mars and the Moon at this time.

Similar views will be seen from the rest of Australia at the equivalent local time (click to embiggen). 

 Evening sky on Saturday July 23 as seen from Adelaide at 23:00 am ACST. 

Saturn forms a triangle with delta and gamma Capricornii, and Jupiter is just above the horizon.

The insets is the telescopic view of Saturn and Jupiter at the same magnification at this time.

Similar views will be seen from the rest of Australia at the equivalent local time. 

Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes before sunrise).

Scorpius is prominent above the northern horizon with the teapot of Sagittarius below. From the Sting of the Scorpion through the teapot there is a wealth of binocular objects to discover.

Between the bright star Canopus and the Southern Cross are another wealth of binocular objects to discover. 

 Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset). 

Mercury is lost in the twilight but will be visible above the western horizon low in the twilight next week. 

Venus is lowering in the morning twilight. The crescent Moon is close to Venus on the 26th/27th.

Mars forms a line with Saturn, Jupiter, and Venus (and Uranus and Neptune). The waning Moon is very close to Mars on the 22nd.

Jupiter climbs higher in the morning twilight below Saturn and above Mars. Jupiter enters the evening sky low above the horizon.

Saturn climbs away from Mars, Jupiter, and Venus. Saturn forms a triangle with delta and gamma Capricornii.

Labels: weekly sky

# posted by Ian Musgrave @ 10:52 pm 0 comments

Full Moon July 14 05:00 AEST. perigee July 13 19:00 (-9h, closest this year)	Full Moon December 8 14:00 AEST  Moon at apogee 12th +3d20h

July 14 is the best perigee Full Moon this year. The differences are in Full Moon size are subtle, especially if you compare tonight's Full Moon with the June 15 Full Moon which was also a perigee Full Moon.  

It requires a keen eye and good memory to distinguish a perigee "super" Moon from more ordinary moons, the best contrast is with the apogee "mini" moon of December 8, even though this is not a good apogee Moon). 

That doesn't mean you shouldn't try though. Daniel Fischer has been able to see the difference, you can read his account and viewing tips here
http://earthsky.org/space/can-you-discern-supermoons-large-size-with-the-eye-an-observer-says-yes

Photographing them can be more rewarding. You can see images of perigee Moon and apogee Moon pairs from 21 Jan 2019 here and 10 August 2014 here.Tips for photographing them are here.

A full Moon at perigee has been called a "Super Moon", this is not an astronomical term (the astronomical term is perigee syzygy, but that doesn't trip off the tongue so nicely), but an astrological one first coined in 1979 (see here).

Still, it is a good excuse to get people out and looking at the Moon (although technically the Moon was full at 5 am this morning and biggest as it was closest to perigee which occurred at 7 pm on the 13th, but the sky was covered in cloud then, it will still look good tonight).
 

Labels: astrophotography, Moon, perigee, unaided eye

# posted by Ian Musgrave @ 6:07 pm 0 comments

The Full Moon is Thursday July 14. This is a Perigee Full Moon, the best this year. The Last Quarter Moon is Thursday July 21. Four bright classical planets in a line in the morning sky, Saturn, Jupiter, Mars and Venus. The waning Moon is close to Saturn on the 15/16th and close to Jupiter on the 19th.

The Full Moon is Thursday July 14. This is a Perigee Full Moon, the best this year. Perigee is July 13. The Last Quarter Moon is Thursday July 21. 

 Evening sky on Friday July 16 as seen from Adelaide at 23:00 ACST. 

The waning Moon is close to Saturn (which in turn forms a triangle with delta and gamma Capricornii).

The insets is the telescopic view of Saturn at this time.

Similar views will be seen from the rest of Australia at the equivalent local time (click to embiggen).

 Morning sky on Tuesday July 19 as seen from Adelaide at 6:24 am ACST (60 minutes before sunrise). 

Four bright classical planets are visible in a line in the morning sky, Saturn, Jupiter, Mars and Venus.

The insets are the telescopic views of the planets at the same magnification at this time, Ganymede and Io are close to Jupiter.

Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes before sunrise, click to embiggen). 

Perigee was on July 13, 10:00, 9 hours before exact full Moon, the closest paring of perigee and Full Moon this year.

Similar views will be seen from the rest of Australia at the equivalent local time.

Scorpius is prominent above the South Eastern horizon with the teapot a Sagittarius below. From the Sting of the Scorpion through the teapot there is a wealth of binocular objects to discover.

Between the bright star Canopus and the Southern Cross are another wealth of binocular objects to discover. 

 Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset). 

Mercury is lost in the twilight.

Venus is lowering in the morning twilight.

Mars forms a line with Saturn, Jupiter, and Venus (and Uranus and Neptune).

Jupiter climbs higher in the morning twilight below Saturn and above Mars. On the 19th Jupiter is close to the waning Moon.

Saturn climbs away from Mars, Jupiter, and Venus. The waning Moon is close to Saturn on the 15/16th

Labels: weekly sky

# posted by Ian Musgrave @ 10:44 pm 0 comments

The First Quarter Moon is Thursday, July 7, the Full Moon is Thursday July 14. This is a Perigee Full Moon, the best this year. Four bright classical planets in a line in the morning sky, Saturn, Jupiter, Mars and Venus.

The First Quarter Moon is Thursday, July 7, the Full Moon is Thursday July 14. This is a Perigee Full Moon, the best this year. Perigee is July 13.

The five bright classical planets are visible in a line in the morning sky, Saturn, Jupiter, Mars, Venus, and Mercury. (Uranus, Neptune and the Asteroid Vesta are in the line too, but all need at least binoculars to see).

The insets are the telescopic views of the planets at the same magnification at this time, Europa is behind Jupiter and Callisto is skimming Jupiter's Pole.

Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes before sunrise, click to embiggen). 

Perigee was on July 13, 10:00, 9 hours before exact full Moon, the closest paring of perigee and Full Moon this year.

Similar views will be seen from the rest of Australia at the equivalent local time.

Scorpius is prominent above the South Eastern horizon with the teapot a Sagittarius below. From the Sting of the Scorpion through the teapot there is a wealth of binocular objects to discover. However, the waxing Moon makes them more difficult to see. The following day (Sunday) the Moon is in the head of Scorpius.

Between the bright star Canopus and the Southern Cross are another wealth of binocular objects to discover. 

 Elsewhere in Australia will see a similar view at the equivalent time (90 minutes after sunset). 

Mercury is lost in the twilight.

Venus is lowering in the morning twilight.

Mars forms a line with Saturn, Jupiter, and Venus (and Uranus and Neptune).

Jupiter climbs higher in the morning twilight below Saturn and above Mars.

Saturn climbs away from Mars, Jupiter, and Venus.

Labels: weekly sky

# posted by Ian Musgrave @ 9:39 pm 1 comments