Astroblog

To be read in conjunction with the tangent section of the astrophiz podcast #243

 https://soundcloud.com/astrophiz/astrophiz-243-october-sky-guide-saturn-opposition-orionids-venus

 

Labels: Astrophiz, bio-signatures, life, Venus

To be read in conjunction with the astrophiz podcast #243

https://soundcloud.com/astrophiz/astrophiz-243-october-sky-guide-saturn-opposition-orionids-venus 

The northern sky as seen at 23:00 ACDST from Adelaide on October 11 (New Moon). The Andromeda galaxy is indicated by the box. Similar views will been seen elsewhere in Australia at the equivalent local time.

The Southern sky as seen at 23:00 ACDST from Adelaide on October 11 (New Moon).  The constellation of Octntis (Octant) is indicated, the cricle marks Sigma Octanits, the box Mel227 and the inset the binocular view of star delta Octanits and the nice pair of Pi Octantis.  The small and large Magellanic clouds are also seen. Similar views will been seen elsewhere in Australia at the equivalent local time.

Scorpius forms a reversed question mark setting above the western horizon.

Sagitarius and with it the centre of the galaxy have departed the Zenith but it still remains an excellent binocular hunting ground. In the lid of the “teapot of Sagittarius is the great globular cluster M22, well worthwhile in binoculars, and nearby the triffid and lagoon nebula. 

Around midnight the famous Andromeda galaxy is low to the north but should be easily visible in binoculars. At the same time one of our companion galaxies, the Lesser Magellanic cloud and the magnificent globular cluster 47 Tucana are quite high almost due south and a delight in binoculars.

At around 10:00 pm local time the Southern Cross will almost be at the 5’oclock position in the sky. Most of the magnificent Southern clusters and nebula are sitting on the southern horizon, however.
Almost due south of the small Magellanic cloud is the faint and undistinguished triangular constellation of Octantus, the Octant, the navigation instrument that first helped chart the southern skies for European explorers. 

Octanus contains the “south pole star” sigma Octantis, a hard to see 5th Magnitude star close to the south celestial pole. In binoculars, near the broad base of the triangle is the faint open cluster Mel 227. Sweeping down towards the point of the triangle and close to the brighter star delta octanits that forms the point is the nice pair of Pi Octantis.

Here are links to printable PDF maps of the Eastern sky at 10 pm ACST, Western sky at 10 pm ACST. 

Meteors:  

 

Morning sky as seen from Adelaide facing north at 4:00 am ACDST on 22 October, the Orionid radiant is indicated with a starburst. Similar views will be seen elsewhere in Australia at an equivalent local time. Click to embiggen.

The Orionids are a normally worthwhile shower, best seen between 2-4 am, the radiant being just under Betelgeuse, the bright red star in Orion. This year the waning Moon will significantly interfere with viewing in the early evening and the rates will be low, once the moon sets around 4 am the rates will be better. The best viewing is the mornings of the 21st to 23rd with the highest rates on the morning of the 22nd, when between 4-5 am under dark skies you should see about a meteor every 4-5 minutes or so.

 

Labels: Astrophiz, Monthly sky

The Last Quarter Moon is Saturday October 3.  Daylight savings starts on the 4th. Saturn is at opposition, when it is biggest and brightest as seen from Earth, on the 4th. Mars forms a line with the bright stars Castor and Pollux and is close to the waning Moon on the 5th. Jupiter is low in the morning sky is close to the crescent Moon on the 6th-7th. In the evening, Venus is slowly sinking and Mercury is rising, the pair are close on the 6th-7th. 

The Last Quarter Moon is Saturday October 3.  Daylight savings starts on the 4th. The Moon is at
perigee (when it is closest to Earth) on the 2nd.

Labels: weekly sky

The Full Moon is Sunday September 27.  Saturn is rising before astronomical twilight. The Full Moon is close to Saturn on the 27th. Mars forms a line with the bright stars Castor and Pollux. Jupiter is low in the morning sky. In the evening, Venus is slowly sinking and Mercury is close to the bright star Spica in the twilight on the 26th. 

The Full Moon is Sunday September 27. 

Labels: weekly sky

The apogee First Quarter Moon is Saturday September 19.  Saturn is rising at astronomical twilight. Mars forms a line with the bright stars Procyon and Pollux. Jupiter is low in the morning sky. In the evening, Venus is becoming brighter and is at maximum brilliance on the 19th. Mercury is low on the horizon. Earth is at Equinox on the 23rd when the day is more or less equal to night in length.

The First Quarter Moon is Saturday September 19. This is an apogee First Quarter Moon, when it is furthest from the earth. Earth is at Equinox on the 23rd when the day is more or less equal to night in length.

Labels: weekly sky

Labels: Antares, binocular, Occultation, telescope

The New Moon is Friday September 11.  Saturn is rising around 8:00 pm local time. Mars is close to Wasat (δ Geminorum). Jupiter is low in the morning sky. In the evening, Venus is becoming brighter with the bright star Spica below and Mercury just over the horizon. The crescent moon is close to Venus on the 14th. Occultation of Antares on the 17th.

The New Moon is Friday September 11.

Western sky on the evening of  Monday,  September 14  as seen from Adelaide at 19:30ACST (90 minutes after sunset, click to embiggen). 

Venus is well above the horizon when the sky is fully dark. The bright star Spica is below it and mercury is peeping above the horizon.

mercury will rise higher in the twilight over the coming week.  

Venus is a clear "Crescent Moon"  shape and is increasing in size.  The shape is readily visible in even small telescopes (although the brightness may make it hard to see). 

 

 

 

Similar views will be seen from the rest of Australia at roughly the equivalent local time  (90 minutes after sunset). 

Eastern horizon on the evening of Saturday,  September 12 as seen from Adelaide at 22:00 ACST (click to embiggen). 

Saturn is the brightest object above the eastern horizon. Saturn is rising around 8:00 pm local time, but is still best for telescopic observation in the morning, and its rings are widening.

The inset shows the telescopic view of Saturn at this time.    

 

 

 

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

The western sky at 23:37 ACST Tuesday, September 17, as seen from Adelaide. The Moon is about to occult the bright star Antares low on the horizon.

 

 

 

 

 

The inset shows the telescopic view at the time. (click to embiggen). 

 

This is an occultation best seen from the east coast south of Sydney around midnight with a level, unobstructed horizon. The Moon is approaching First Quarter and is low above the horizon. The Moon sets before Antares can reappear.

Place	Disappears Bright Limb	Reappears Dark Limb
Adelaide ACST	23:37	-
Brisbane  AEST	-	-
Canberra AEST (18th)	00:00	-
Darwin ACST	-	-
Hobart AEST	23:51	-
Melbourne AEDST	23:59	-
Perth AWST	-	-
Sydney AEST	-	-

 

Labels: weekly sky

The Last Quarter Moon is Friday September 4.  Saturn is rising around 8:30 pm local time. Mars is close to the Crescent Moon on the 7th. In the evening, Venus is becoming brighter and is leaving the bright star Spica behind. 

The Last Quarter Moon is Friday September 4. The Moon is at perigee on September 7.

Western sky on the evening of  Saturday,  September 5  as seen from Adelaide at 19:24ACST (90 minutes after sunset, click to embiggen). 

Venus is well above the horizon when the sky is fully dark. It is now leaving the bright star Spica behind.

Venus is a clear "Crescent Moon"  shape and is increasing in size.  The shape is readily visible in even small telescopes (although the brightness may make it hard to see). 

 

 

 

Similar views will be seen from the rest of Australia at roughly the equivalent local time  (90 minutes after sunset). 

Eastern horizon on the evening of Saturday,  September 5 as seen from Adelaide at 22:00 ACST (click to embiggen). 

Saturn is the brightest object above the eastern horizon. Saturn is rising around 8:30 pm local time, but is still best for telescopic observation in the morning, and its rings are widening.

The inset shows the telescopic view of Saturn at this time.    

 

 

 

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

Labels: weekly sky

To be read in conjunction with the astrophiz podcast #241

 Mercury enters the evening twilight late in the month. From the 16th it can be seen low above th western horizon, forming a line with Spica and Venus, On the 26th, Mercury will be less than a degree from 1st magnitude Spica, with Venus above.

Venus is now in Virgo. It begins to sink in the evening sky dut is still well visible after the sky is fully dark. Venus is a distinct “Crescent Moon” phase in even small telescopes. For the first couple of days, Venus will be less than 2°from Virgo’s brightest star, Spica. On the 14th, Venus is 2°from the 4-day-old waxing crescent Moon, an impressive sight in the evening sky. On the 19th, Venus is at its greatest brilliance at − 4.5 magnitude.

Saturn is rising higher ahead of opposition next month, when it is biggest and brightest as seen for earth.  At the beginning of the-month it is rising around 8:30 pm and is highest at 2:30 am. Mid-month it is rising around astronomical twilight and is highest around 1:30 pm. By the end of the Month, it is highest around midnight. On September 27th the full Moon is ~6° from Saturn. The rings are widening

Morning sky:

Mars is above the eastern horizon at astronomical twilight in the morning. Mars in Gemini. On the 7th, it is 4° south of the 25-dayold waning crescent Moon. 

Saturn is highest around 2pm to midnight as the month rolls on. While in a good viewing position in the evening, it is still best telescopically in the very early morning. 

Jupiter enters the morning sky and -is low above the horizon. On the 9th, the planet will be around 2° from the 27-day‑old waning crescent Moon, low above the horizon it the twilight. By the end of the month it is still low, but more readily seen.

September 4	Last Quarter Moon (ideal for star gazing)
September 7	Moon at perigee
September 11	New Moon (also ideal for star gazing total solar eclipse northern hemisphere)
September 19	First Quarter Moon (Moon at apogee)
September 27	Full Moon

The northern sky as seen at 19:28 ACST from Adelaide on September 11 (90 minutes after sunset, New Moon). The bright stars Altair, Deneb and Vega are seen forming the 'Winter triangle" in the northern sky.  Sagittarius is at the Zenith and  the location of the globular cluster M22 is indicated by the box. The inset shows the telescopic view. Similar views will been seen elsewhere in Australia 90 minutes after sunset.

The Southern sky as seen at 19:28 ACST from Adelaide on September 11 (90 minutes after sunset, New Moon). The bright stars alpha and beta Centauri are readily visible with the Southern Cross below. The globular clusters 47 Tucana and Omega Centauri are  indicated. The inset shows the telescopic view of 47 Tucana. The small and large Magellanuic clouds are also seen. Similar views will been seen elsewhere in Australia 90 minutes after sunset.

 Scorpius the scorpion is now heading westwards.  Sagittarius, and the heart of the Milky way, is at the zenith from around 8 pm. This is an excellent time to observe the wealth of clusters in this area. The magnificent globular cluster M22 is at its highest that this time. It’s rival Omega Centauri is setting but still high and readily visible, and the other magnificent globular cluster 47 Tucana is rising. The three form a broad triangle across the Southern Sky. To the north the winter triangle of Deneb, Vega and Altair is clear

By mid month, the classic Andromeda galaxy is seen rising low above the northern horizon, while in the south the two dwarf galaxies, the Magellanic clouds, are rising too, with the SMC almost at its highest.

The southern cross is at about the 4 o'clock position, with the pointers above, just to the south of the pointers is the obviously triangular constellation of Triangulum Australae, the above that is Ara, the altar. These dim constellations are often overlooked but are interesting and have some nice small clusters in them. 

Meteors: No notable meteor showers this month.

Labels: Astrophiz, Monthly sky