Astroblog

Eastern horizon on the morning of Thursday, April 16 as seen from Adelaide at 5:44 ACST (60 minutes before sunrise, click to embiggen). The Crescent Moon, Mercury, Mars and Saturn for a triangle approximately one hand-span across low to the horizon.	Eastern horizon on the morning of Sunday, April 19 as seen from Adelaide at 5:48 ACST (60 minutes before sunrise, click to embiggen). Mercury, Mars and Saturn for a triangle low to the horizon.
Eastern horizon on the morning of Monday, April 20 as seen from Adelaide at 5:48 ACST (60 minutes before sunrise, click to embiggen). Mercury, Mars and Saturn for a close triangle low to the horizon. Mars is closest to Saturn on the 20th (1.1°). The inset is the binocular view at the time.	Eastern horizon on the morning of Tuesday, April 21 as seen from Adelaide at 5:48 ACST (60 minutes before sunrise, click to embiggen). Mercury, Mars and Saturn for a close triangle low to the horizon. Mercury is 0.6° from Saturn and 1.6° from Mars. The inset is the binocular view at the time.

 

 Over the past fews days in the morning twilight three bright planets, Mercury, Mars and Saturn, have been drawing closer.

On the 16th there is an attractive massing with three unaided eye planets just above the eastern horizon, all within a 6° circle. 

Mercury at the top is 4° from Mars and 6° from Saturn, as a bonus, the slender crescent of the waning 28-day-old Moon is nearby. The planets then come closer and form a close triable between the 19th to 21st.

Mars is closest to Saturn on the 20th (1.1°). 

On the 21st another nice close conjunction occurs with Mercury 0.6° from Saturn and 1.6° from Mars. Mars has close approaches with the Moon on the 16th (3°), Saturn on the 20th (1.1°) and Mercury on the 21st (1.7°).  

After the close massing from the 23rd the planets stretch out into a line with Mercury heading towards the horizon and fading.

Labels: Mars, massing, Mercury, Moon, Saturn, unaided eye

North-western sky on the evening of Saturday, February 28 as seen from Adelaide at 20:20 ACDST (30 minutes after sunset, click to embiggen).	Western sky on the evening of Saturday, February 28 as seen from Los Angeles at 18:29 local time (30 minutes after sunset, click to embiggen).

Despite a variety of claims on the internet, you won't be able to see all 6 planets lined up on February 28, 2026 (UPDATE).

The good news is that they are lined up. The bad news is that they are too deep in the twilight to see. 

At civil twilight, 30 minutes after sunset, if you have a clear, level, unobstructed horizon, Mercury, Venus, Saturn and Neptune are invisible in the twilight glow (Mercury has set in the southern hemisphere), as is Uranus. Jupiter *might* just be visible. 

Venus may be visible in binoculars (or if you have very good eyesight) in the Northern hemisphere low in the twilight if the horizon conditions are clear. UDPATE: In some places in the Northern hemisphere, Venus may be high enough to see at nautical twilight. Daniel Fischer was able to image it at nautical twilight in Bochum in the EU https://scicomm.xyz/@cosmos4u/116133837700056539 .

60 minutes later at astronomical twilight, when the sky is darker, Venus and Saturn have set (well they are right on the horizon in the Northern Hemisphere and still is high in some places see update above) and Uranus will be just visible in binoculars (Jupiter will be well visible).

Labels: lineup, Mercury, Neptune, public outreach, Saturn, Venus

The table below shows significant astronomical events that can be seen with the unaided eye or minimal equipment in 2023 in Australia (and to some degree elsewhere in the Southern Hemisphere, ocultations and eclipses are very region specific). 

This year we get a Partial Lunar eclipse best visible from western Australia. A Total Solar eclipse is visible from the tip of Western Australia and everywhere else sees a partial eclipse (best from WA and central north). There are good oppositions of Jupiter and Saturn. We also get an occultation of the Pleiades and a binocular comet.

As well we have some fantastic parings and lineups and good meteor showers.

Close pairings of the Moon and bright planets are given special attention as not only is the Moon a ready guide to locating the planets if you are not familiar with them, these massings are rather beautiful. 

Special events are bolded.

Date	Event
January
3 January 2023	Moon between Mars and Pleiades
5 January 2023	Earth at Perihelion
21 January 2023	Crescent Moon near Mercury in morning twilight.
23 January 2023	Saturn, Venus and Crescent Moon close in the evening twilight
26 January 2023	Crescent Moon close to Jupiter
February
4 February 2023	Comet C/2022 E3 visible above northern horizon (binocular)
11-13 February 2023	Comet C/2033 E3 comes close to Mars the enters the Hyades (binocular)
19 February 2023	Crescent Moon and Mercury close in the morning twilight
22 February 2023	Crescent Moon near Venus in evening twilight
23 February 2023	Crescent Moon close to Jupiter.
28 February 2023	Waning Moon close to Mars
26-30 February 2023	Venus and Jupiter come close together ahead of a spectacular conjunction in March
March
2 March 2023	Venus and Jupiter in a spectacular close approach (0.5 degrees) in evening twilight
3 March 2023	Mercury very close (1 degrees) to Saturn deep in morning twilight
20 March 2023	Crescent Moon and Saturn close in early morning twilight
21 March 2023	Earth at Equinox
24 March 2023	Crescent Moon and Venus close in evening twilight
28 March 2023	Waning Moon close to Mars.
April
12 April 2023	Venus near the Pleiades.
16 April 2023	Saturn and crescent Moon close in morning sky.
20April 2023	Total Solar Eclipse; Exmouth WA (partial in the rest of Australia)
23April 2023	Crescent Moon close to Venus in evening sky
26 April 2023	Waxing Moon close to Mars in evening sky
May
5/6 May 2023	Penumbral eclipse of the Moon
6-7 May 2023	Eta Aquariid meteor shower
14 May 2023	Waning Moon close to Saturn in the morning sky
18 May 2023	Mercury, Jupiter and crescent Moon form a triangle in morning twilight
23 May 2023	Crescent Moon below Venus in the evening sky
24-25 May 2023	Mars with waxing Moon nearby
June
3 June 2023	Mars in heart of Beehive cluster (M44), Venus forms line with Castor and Pollux
10 June 2023	Saturn near waning Moon in morning sky
14 June 2023	Crescent Moon near Jupiter in morning sky, Venus near Beehive cluster in evening sky
17 June 2023	Thin Crescent Moon, Mercury and red star Aldebaran form a line low in the morning twilight
22 June 2023	Earth at solstice
22 June 2023	Crescent  Moon forms triangle with Mars and Venus in evening sky
July
7 July 2023	Earth at aphelion, waning Moon near Saturn in the morning sky.
8 July 2023	Venus at greatest brilliance
10 July 2023	Venus, Mars and the bright star Regulus form a triangle in the evening twilight
12 July 2023	Crescent Moon close to Jupiter in the morning sky
19 July 2023	Thin Crescent Moon close to Mercury low in evening twilight
20 July 2023	Crescent Moon, Venus and bright star Regulus for a triangle in the evening twilight
21 July 2023	Mars near crescent Moon in the morning twilight
26 July 2023	Venus, Mercury and Regulus form a triangle
30 July 2023	Mercury Very close (0.5 degrees) to Regulus, Venus close by
29-30 July 2023	Southern Delta Aquarids meteor shower
August
2 August 2023	Perigee Full Moon (“super” Moon)
3 August 2023	Saturn close (2 degrees) to Moon in evening sky
8-9 August 2023	Jupiter near waning Moon
18 August 2023	Thin crescent Moon forms triangle with Mercury and Mars in evening twilight
19 August 2023	Thin crescent Moon forms line with Mercury and Mars in evening twilight
27 August 2023	Saturn at opposition
30 August 2023	Saturn  near waxing Moon in evening
31 August 2023	Perigee Full Moon (“Super” Moon) also Blue Moon
September
4 September 2023	Jupiter close to waning Moon in evening sky
12 September 2023	Thin crescent Moon close to Venus in dawn sky
16-17 September 2023	Crescent Moon near Mars
23 September 2023	Earth at Equinox
27 September 2023	Saturn close to the waxing Moon
October
1-2 October 2023	Jupiter  and waning Moon near in evening sky
11 October 2023	Venus and crescent Moon close in morning sky
24 October 2023	Saturn and the waxing Moon close in evening sky
21-22 October 2023	Orionid meteor shower
28 October 2023	Twilight partial eclipse of the Moon (best from WA)
29 October 2023	Jupiter and the Full Moon close in evening sky
30-31 October 2023	Ocultation of the Pleiades (before  midnight 30th to early morning 31st)
November
3 November 2023	Opposition of Jupiter
10 November 2023	Crescent Moon near Venus in morning sky
14 November 2023	Opposition of Uranus
18 November 2023	Leonid Meteor Shower
20 November 2023	Waxing Moon near Saturn in the evening sky
25 November 2023	Waxing Moon near Jupiter in Evening sky
29 November 2023	Occultation of bright star Beta Tauri in morning sky
December
10 December 2023	Venus and crescent Moon close
14 December 2023	Geminid Meteor shower in the morning
14 December 2023	Mercury near thin crescent Moon low in the twilight
17-18 December 2023	Waxing Moon near Saturn in the evening
22 December 2023	Earth is at Solstice
22 December 2023	Jupiter near waxing Moon in the evening
23 December 2023	Asteroid Vesta at opposition
31 December 2023	Venus, Mercury and Mars form a triangle low the twilight morning sky

Labels: Asteroid, Conjunction, eclipse, Jupiter, Mars, Mercury, Moon, Opposition, Saturn, unaided eye, Venus, Yearly Sky Events

Morning sky on Sunday June 12 as seen from Adelaide at 5:50 am ACST (90 minutes before sunrise). Saturn, Jupiter, Mars, Venus and Mercury form a line (Uranus, Neptune and the Asteroid Vesta are in the line too, but all need at least binoculars to see). Venus and Uranus are at their closest.The inset shows the binocular appearance of  Venus and Uranus at this time. Similar views will be seen from the rest of Australia at the equivalent local time (90 minutes before sunrise, click to embiggen).	Morning sky on Sunday June 19 as seen from Adelaide at 5:52am ACST (90 minutes before sunrise). The waning Moon is near Saturn. Similar views will be seen from the rest of Australia at the equivalent local time (90 minutes before sunrise, click to embiggen).	Morning sky on Wedensday June 22 as seen from Adelaide at 5:53 am ACST (90 minutes before sunrise). The waning Moon is near Jupiter. Similar views will be seen from the rest of Australia at the equivalent local time (90 minutes before sunrise, click to embiggen).
Morning sky on Thursday June 23 as seen from Adelaide at 5:53 am ACST (90 minutes before sunrise). The crescent Moon is near Mars.The inset shows the binocular appearance of the Moon and Mars at 3:00 am local time. Similar views will be seen from the rest of Australia at the equivalent local time (90 minutes before sunrise, click to embiggen).	Morning sky on Saturday June 25 as seen from Adelaide at 5:53 am ACST (90 minutes before sunrise). The Moon and and Uranus are at their closest (occultation in WA, NT and FNQ). The inset shows the binocular appearance of the Moon and Uranus at this time. Similar views will be seen from the rest of Australia except the occulting states at the equivalent local time (90 minutes before sunrise, click to embiggen).	Morning sky on Sunday June 26 as seen from Adelaide at 6:24 am ACST (60 minutes before sunrise). The crescent moon forms a line with Venus, Aldebaran and Mercury, with the Pleiades cluster close by. Similar views will be seen from the rest of Australia at the equivalent local time (60 minutes before sunrise, click to embiggen).

Over the next three weeks you will be able to see a rather rare sight, if you have clear morning skies. All 5 bright classical planets are lined up in the order they are from the Sun. Mercury, Venus, Mars, Jupiter and Saturn. In February 2016 we also had 5 bright planets in the morning skies but the lineup was Mercury, Venus, Saturn, Mars and Jupiter. We have to go back 21 December 2004 to have all 5 planets in the morning sky in solar order. 

Also, unlike the other times we had all the bright classical planets together in the morning, we also have all the other planets (Uranus, Neptune), the Dwarf planet Pluto and the Asteroid 4 Vesta. These are not is solar system order. 

To make up for this on the 12th we have a close approach of Venus and Uranus. The Moon joins the line-up from the 19th, and we have lots of nice close Moon approaches, with the Moon and Uranus being close on the 25th and occultations in Cairns (Dawn), Darwin, Alice Springs and Perth. 

On the 26th Venus and the thin crescent Moon are close, the Pleiades and Aldebaran and Mercury make this an attractive sight. On the 27th the thin crescent Moon forms  a rectangle with Mercury, Venus and Aldebaran. On the 30th Venus forms a second eye for Taurus the Bull.

Labels: 4 Vesta, Jupiter, Mars, Mercury, Neptune, Occultation, Saturn, unaided eye, Uranus, Venus

The table below shows significant astronomical events that can be seen with the unaided eye or minimal equipment in 2022 in Australia (and to some degree elsewhere in the Southern Hemisphere, ocultations and eclipses are very region specific). 

This year we get a good Total Lunar eclipse. There are good oppositions of Mars, Jupiter and Saturn. Mars skims past the Pleiades and Hydaes clusters.

As well we have some fantastic parings and lineups and good meteor showers.

Close pairings of the Moon and bright planets are given special attention as not only is the Moon a ready guide to locating the planets if you are not familiar with them, these massings are rather beautiful. 

Special events are bolded.

Date	Event
January
1 January 2022	Occultation of Mars
4 January 2022	Earth at Perihelion
4 January 2022	Crescent Moon, Mercury, and Saturn close low in the evening twilight
6 January 2022	Jupiter and Crescent Moon close
30 January 2022	Crescent Moon forms a triangle with Mars and Venus
February
2 February 2022	Mars close to M28
3 February 2022	Jupiter close to the thin crescent Moon low in the twilight
6 February 2022	Mars near globular cluster M22
13 February 2022	Mercury, Mars and Venus form a triangle in the morning sky.
27-28 February 2022	Crescent Moon, Mars and Venus form a triangle in the morning sky.
March
1 March 2022	Mercury, Saturn and thin crescent Moon form a triangle in the morning twilight
3 March 2022	Mercury very close (0.6 degrees) from Saturn in morning twilight
21 March 2022	Earth at Equinox, Five bright planets visible in the morning twilight, Jupiter and Mercury close in the morning twilight.
28 March 2022	Crescent Moon, Saturn, Venus and Mars from a close massing in the morning twilight with the Moon above
29 March 2022	Crescent Moon, Saturn, Venus and Mars from a close massing in the morning twilight with the Moon below
31 March 2022	Thin crescent Moon close to Jupiter low in the morning twilight
April
All April 2022	Four bright planets in the morning sky Moon in the morning sky
5 April 2022	Saturn and Mars very close (0.3 degrees apart) in the morning sky
13 April 2022	Jupiter close to Neptune in the morning sky
26 April 2022	Mars close to the crescent Moon in the morning sky
27-28 April 2022	Crescent Moon close to Venus and Jupiter in the morning sky
28 April 2022	Venus and Neptune in close conjunction (< 30 arc minutes) in the morning sky
May
1  May 2022	Venus and Jupiter very close in the morning sky (0.2 degrees apart)
6-7 May 2022	Eta Aquariid meteor shower
22 May 2022	Waning Moon above Saturn
25 May 2022	Mars, Jupiter and waning Moon form a triangle in morning sky
27 May 2022	Crescent Moon above Venus
30 May 2022	Mars and Jupiter very close in the morning sky (0.6 degrees apart)
June
1 June 2022	Mars and Jupiter very close in the morning sky (1.0 degrees apart)
18 June 2022	Saturn near waning Moon low in the late evening sky
14 June 2022	Perigee Full Moon ("super Moon")
21 June 2022	Earth at solstice
22 June 2022	Mercury in head of Hyades near Aldebaran in morning sky, waning Moon near Jupiter
26 June 2022	Crescent  Moon between Venus and Pleiades in the morning sky
27 June 2022	Crescent  Moon near Mercury in the morning sky
July
1 July 2022	Venus close to Aldebaran in the morning, forming a second eye for Taurus the Bull
4 July 2022	Earth at aphelion
14 July 2022	Syzygy Perigee full moon ("super Moon") closest of year
15 July 2022	Moon close to Saturn
19 July	Moon close to Jupiter
22 July 2022	Waning crescent Moon close to Mars (within binocular field)
27 July 2022	Venus near crescent Moon in the morning twilight
29-30 July 2022	Southern Delta Aquarids meteor shower
30 July 2022	Mercury close to crescent moon in western evening twilight
31 July	Mars and Uranus 2 degrees apart (in same binocular filed)
August
1-3 August 2022	Mars and Uranus less than  2 degrees apart (in same binocular filed)
4 August 2022	Mercury very close to Regulus (0.7 degrees) in the evening twilight
12 August 2022	Saturn close to Full Moon (perigee "super" Moon)
15 August 2022	Saturn at opposition
15 August 2022	Jupiter close to Waning Moon (1 degree)
20 August 2022	Mars near Moon in Morning
22 August 2022	Jupiter near Moon
29 August 2022	Mercury near thin crescent Moon in evening sky, Mars between Pleiades and Hyades in the morning sky
September
3 September 2022	Mars forms second "eye" in Taurus the Bull with Aldebaran in morning sky
8 September 2022	Waxing moon close to Saturn in evening sky
11 September 2022	Waning Moon close to Jupiter in evening sky
23 September 2022	Earth at Equinox
27 September 2022	Jupiter at Opposition
October
5 October 2022	Saturn and waxing Moon close in evening sky
8 October 2022	Jupiter and waxing Moon close in evening sky
14 October 2022	Mars and the waxing Moon close in evening sky
21-22 October 2022	Orionid meteor shower
November
2 November 2022	Waxing Moon near Saturn in evening sky
4-5 November 2022	Waxing Moon near Jupiter in evening sky
8 November 2022	Total Lunar Eclipse
11 November 2022	Waxing Moon near Mars in evening sky
18 November 2022	Leonid Meteor Shower
December
2 December 2022	Jupiter and waxing Moon close
8 December 2022	Mars at opposition and close to Full Moon
14 December 2022	Geminid Meteor shower in the morning (waning Moon close this year)
22 December 2022	Earth is at Solstice
24 December 2022	Venus and Mercury and thin crescent Moon are close in evening twilight.
26 December	Saturn near crescent Moon
28-30 December 2022	Venus and Mercury at their closest in evening twilight.
29 December 2022	Jupiter close (1 degree) from the waning Moon in evening

Labels: Asteroid, Conjunction, eclipse, Jupiter, Mars, Mercury, Moon, Opposition, Saturn, unaided eye, Venus, Yearly Sky Events

The table below shows significant astronomical events that can be seen with the unaided eye or minimal equipment in 2021 in Australia (and to some degree elsewhere in the Southern Hemisphere, ocultations and eclipses are very region specific). 

This year we get a good Total Lunar eclipse during a perigee "super" Full Moon and a partial lunar eclipse under very poor conditions. There is a good opposition of Jupiter and Saturn. Mars skims past the Pleiades and Beehive cluster. Venus too skims past the Beehive. There is also a good opposition of Vesta.

While we don't have a spectacular conjunction of Jupiter and Saturn this year, we have some fantastic parings and lineups and good meteor showers.

Close pairings of the Moon and bright planets are given special attention as not only is the Moon a ready guide to locating the planets if you are not familiar with them, these massings are rather beautiful. 

Special events are bolded.

Date	Event
January
2 January 2021	Earth at Perihelion
12 January 2021	Crescent Moon and Venus close low in the morning twilight
14 January 2021	Crescent Moon, Mercury and Jupiter close low in the evening twilight
21 January 2021	Mars and waxing Moon close
21 January 2021	Uranus between Mars and the waxing Moon
February
6-7 February 2021	Venus close to Saturn low in the twilight
11 February 2021	Venus close to Jupiter and the crescent moon low in the twilight
19 February 2021	Mars near first Quarter Moon
20-28 February 2021	Mercury between Jupiter and Saturn in the twilight
28 February 2021	Mars within binocular distance of the Pleiades cluster
March
1-9 March 2021	Mars within binocular distance of the Pleiades cluster, closest on the 2nd
4 March 2021	Asteroid Vesta at opposition, just visible to the unaided eye, best in binoculars
5 March 2021	Mercury very close to Jupiter below Saturn in the morning
10 March 2021	Saturn close to the crescent Moon in the morning
11 March 2021	Mercury close to Jupiter and the crescent Moon in the morning
19 March 2021	Mars near waxing Moon
20 March 2021	Earth at Equinox
April
7 April 2021	Saturn near to the waning Moon in the morning sky
8 April 2021	Jupiter near to the crescent Moon in the morning sky
11 April 2021	Mercury close to the crescent Moon in the morning twilight
17 April 2021	Mars close to the crescent Moon
27 April 2021	Mars on outskirts of open cluster M35 (binoculars best)
28 April 2021	Perigee Full Moon ("super" Moon), 1:00 am
May
4  May 2021	Saturn close to waning Moon in the morning sky
5 May 2021	Jupiter near to the waning Moon in the morning sky
6-7 May 2021	Eta Aquariid meteor shower
14 May 2021	Thin crescent Moon above Mercury in morning sky
26 May 2021	Total eclipse Perigee Full Moon ("super" Moon), 12:00 pm (eclipse from 8 pm)
29 May 2021	Mercury and Venus close low in the twilight (binoculars best)
June
1 June 2021	waning Moon near Jupiter
12 June 2021	Venus near thin crescent Moon low in the evening sky
14 June 2021	Waxing crescent Moon and Mars near in evening sky
21 June 2021	Earth at solstice
23-24 June 2021	Mars crosses beehive cluster (binoculars best)
27 June 2021	Waning Moon close to Saturn
28 June 2021	waning Moon near Jupiter
July
3 July 2021	Venus at the edge of the beehive cluster, best in binoculars
6 July 2021	Earth at aphelion
8 July 2021	Mercury close to the thin crescent Moon in the morning
12 July 2021	Crescent Moon, Venus and Mars close in the evening
13 July 2021	Venus and Mars very close in the evening sky
22 July 2021	Venus very close to bright star Regulus
24 July 2021	Saturn near Moon
26 July 2021	Jupiter near Moon
29-30 July 2021	Southern Delta Aquarids meteor shower
30 July 2021	Mars very close to Regulus
August
2 August 2021	Saturn at opposition
10 August 2021	Mars near thin crescent Moon
11 August 2021	Venus close to crescent Moon
18 August 2021	Variable star Mira predicted to peak in brightness
19 August 2021	Jupiter at opposition
17-21 August 2021	Mercury close to Mars, closest on the 19th
20 August 20	Saturn near Moon
22 August 2021	Jupiter near Moon
September
6 September 2021	Venus close to bright star Spica
9 September 2021	Mercury and crescent Moon close in the evening sky
10 September 2021	Crescent Moon and Venus nearby forming triangle with Spica
17 September 2021	Waxing Moon near Saturn
18 September 2021	Waxing Moon near Jupiter
23 September 2021	Earth at Equinox
21 September 2021	Mercury close to bright star Spica
24 September 2021	Venus close to moderately bright star alpha2 Librae, below Scorpius and above the pair of Mercury and Spica
October
1 October 2021	Mercury and bright star Spica still close
10 October 2021	Venus, the crescent Moon and the bright star Antares form a triangle
14 October 2021	Saturn and the waxing Moon close
15 October 2021	Jupiter and the waxing Moon close
17 October 2021	Venus and the bright star Antares at their closest
21-22 October 2021	Orionid meteor shower
23-24 October 2021	Venus close to globular cluster M19 (binocular or telescope)
November
4 November 2021	Thin crescent Moon close to Mercury low in the twilight
8 November 2021	Venus close to thin crescent Moon below the teapot of Sagittarius
8-24 November 2021	Venus crosses the teapot of Sagittarius
10-11 November 2021	Waxing Moon near Saturn
11-12 November 2021	Waxing Moon near Saturn
18 November 2021	Leonid Meteor Shower
19 November 2021	Partial Lunar eclipse, difficult with mid eclipse in the twilight
December
3 December 2021	Mars and thin crescent Moon close low in the morning twilight
7-10 December 2021	Three bright planets form a line in the evening with the thin crescent. moon joining them, Venus and Moon close on the 7th
8 December 2021	Saturn and crescent Moon close
10 December 2021	Jupiter and crescent Moon close
14 December 2021	Geminid Meteor shower in the morning (waxing Moon sets before best rates)
18 December 2021	Apogee Full Moon (12:00 pm)
21 December 2021	Earth is at Solstice
23-30 December 2021	four bight planets, Mercury, Venus, Saturn and Jupiter line up in the evening twilight, on the 29th Venus and Mercury are at their closest.
1 January 2022	Thin crescent Moon very close to Mars low in the morning sky. Occultation seen in south eastern and south central Australia

Labels: asteroids, Conjunction, eclipse, Jupiter, Mars, Mercury, Meteors, Opposition, Saturn, unaided eye, Venus, Yearly Sky Events

Mercury has a tail! And late September and early October will be the best times for amateurs to try and image it. Before going into details, a bit of background (this is an extended version of the tangent I did for the astrophiz podcast, the mercury tail talk starts around 17:11)

Back in 2008 famed STEROHUNTER Comet Al and I were trying to confirm a comet position in images from STEREO A. I pointed out the nice bright comet moving across the STEREO image field and Comet Al said, "That's not a comet, that's Mercury!". We exchanged the internet equivalent of startled looks. 

The feeling on the Stereohunter list was that it was an artifact, but I remembered an article on sodium emission from Mercury, and went to track down the group and ask them what they thought our tail might be. 

So began a saga that cumulated in the paper "Observations of Mercury’s Escaping Sodium Atmosphere by the STEREO Spacecraft" by Carl Schmidt, Jeffrey Baumgardner, Michael Mendillo, Christopher Davis and Ian Musgrave being read at the European Planetary Science Congress. This paper was the subject of a press release, and has spread wide into the internet (Science Daily, Space.com, and SpaceInfo are just a few examples). It is my first and only scientific paper on astronomy (as very minor co-author of course).

The intense heat of the Sun blasts sodium ions from Mercury’s surface into space. We can see this tail of sodium atoms as glow as they are ionized by the Sun’s UV light. The Moon also as a tail of sodium atoms streaming away from it. 

So why bring it up now? In the wake of Karl Battams magnificent video of Comet C/1999 Y4 (Atlas) as it passed through the STEREO H1 field of view, also featuring Mercury’s sodium tail the question arose, can Mercury’s sodium tail be picked up by amateur astronomers? 

Mercury’s tail has been picked up from Earth by specialized astronomical telescopes with special filters. But what about amateurs? It turns out that they can. There have been several images of Mercury taken by amateurs with fairly modest telescopes and narrow band filters (see here for example). Narrow band filers are widely available (but somewhat pricey) a recent successful imaging used a 589.3/1.0 nm filer, sodium atoms need 589.0/589.6 nm light to glow. 

Image from Qiсһеng Ζһаng. Mercury and its sodium tail on June 4 through a 60 mm refractor and a 589.3/1.0 nm band-pass filter. The trailed star to the lower left is HIP 31650 (it's Qicheng's image, so play nice).

But you will need a guided telescope and integrate a number of exposures (eg 100x 10 second exposures). Could you pick the tail up with simple broadband exposure rather than a narrow-band filter? That is a good question and maybe you could try if you have a guided telescope. 

Evening sky at 19:45 ACST (90 minutes after sunset) on Friday, October 2 facing west as seen from Adelaide. At this time Mercury is at it's furthest elongation from the Sun. Mercury is easily seen above the Western horizon at astronomical twilight.  

In September and October Mercury will be relatively high and good for trying. Mercury’s sodium tail is brightest at perihelion and aphelion. Aphelion is on September 19, but Mercury is only 4 degrees above the horizon at astronomical twilight, when the sky is full dark at the time. 

Mercury is 7 degrees above the horizon at astronomical twilight between the 24th to 29th of September, which is better, but the tail will be fading. 

While fading, this will be an excellent challenge for the telescope owners. 

If you want to read more, there are some excellent academic papers here and here (hat tip to Daniel Fischer for the links)

Labels: Mercury, Stereo Satellite

Morning sky at 5:44 ACST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Tuesday, April 14.	Morning sky at 5:44 ACST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Wednesday, April 15.
Morning sky at 5:45 ACDST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Thursday, April 16	Morning sky at 5:46 ACDST (60 minutes minutes before sunrise) facing east as seen from Adelaide on Friday, April 17

The next four days offers some excellent sky viewing if you are prepared to get up in the early hours.

Staring tomorrow morning the Moon climbs down the ladder of planets. On Tuesday the 14th the waning Moon aligns with the four bright planets, on Wednesday the 15th the last quarter Moon is close to Jupiter, on Thursday the 14th the crescent Moon is between Saturn and Mars and finally on the Friday 17th the crescent Moon lines up with the planets again.

On the 22nd Mercury and the thin crescent Moon will be difficult to see low in the twilight.

On the 15th the Moon and Jupiter are in binocular range, but sadly not in telescope range. 

Labels: alignment, Jupiter, Mars, Mercury, Moon, Saturn, unaided eye

Morning sky at 5:52 ACDST (90 minutes minutes before sunrise) facing east as seen from Adelaide on Wedensday, March 18.	Morning sky at 5:53 ACDST (90 minutes minutes before sunrise) facing east as seen from Adelaide on Thursday, March 19.
Morning sky at 5:55 ACDST (90 minutes minutes before sunrise) facing east as seen from Adelaide on Saturday, March 21.	Morning sky at 5:56 ACDST (90 minutes minutes before sunrise) facing east as seen from Adelaide on Sunday, March 22.

Staring on the morning of Wednesday 18 March there is a outstanding line up of 4 bright planets and the Moon, each day the Moon moves down the line-up bring superb views.

Two outstanding ones are on the 19th when Mars, Jupiter, Saturn and the crescent moon from an attractive grouping in the sky and on the 21st When Mars is cloosest to Jupiter. 

The display finishes on the 22nd with the thin crescent Moon near mercury.

This is an excellent opportunity of astrophotography, as well as just being great to watch with the unaided eye.

Labels: astrophotography, Conjunction, Jupiter, Mars, Mercury, Moon, Saturn, unaided eye

Jupiter and Saturn on 12 December 2020 at 21:25 ACDST, (60 Minutes after Sunset) as seen from Adelaide, the inset shows the approximate telescopic view of Jupiter and the ringed world with a 4" Newtonian and a 6 mm eyepiece. Most of Australia will enjoy similar views 60 Minutes after Sunset (although you may want to observe earlier if your telecope can not point to far downwards). we may have to wait another 20 years to see a similar pairing. Click to embiggen.

The table below shows significant astronomical events that can be seen with the unaided eye or minimal equipment in 2020 in Australia (and to some degree elsewhere in the Southern Hemisphere, ocultations and eclipses are very region specific). This year we only get penumbral Lunar eclipses under very poor conditions. There is a very good opposition of Mars though, and a spectacular Jupiter and Saturn conjunction. Venus travels through the Pleiades and displays its crescent form.

Close pairings of the Moon and bright planets are given special attention as not only is the Moon a ready guide to locating the planets if you are not familiar with them, these massings are rather beautiful. 

Special events are bolded.

Date	Event
January
11 January 2020	Penumbral lunar eclipse in the morning, close to dawn.
21 January 2020	Crescent Moon and Mars close in the morning
23 January 2020	Crescent Moon and Jupiter close in the morning
27 January 2020	Venus and Neptune close
26 January 2020	Mercury close to the crescent moon in the evening twilight
28 January 2020	Venus close to the crescent moon in the evening
February
18 February 2020	Mars passes between the triffid and Lagoon Nebulae
19 February 2020	Waxing Moon close to Mars in the morning
20 February 2020	Waxing Moon extremely close to Jupiter in the morning
21 February 2020	Waxing Moon close to Saturn in the morning
27 February 2020	Waning Crescent Moon close to Venus
29 February 2020	Mars close to Globular cluster M22
March
1 March 2020	Mars still close to Globular cluster M22
8-9 March 2020	Venus close to Uranus (binocular only)
18 March 2020	Waning Crescent Moon forms a line with Mars, Jupiter and Saturn in the morning sky
19 March 2020	Crescent Moon between Mars and Jupiter and Saturn
20 March 2020	Earth at Equinox
21 March 2020	Mars very close to Jupiter
22 March 2020	Mercury close to the crescent Moon in the morning
29March 2020	Venus close to the crescent Moon in the evening
April
1 April 2020	Saturn close to Mars in the morning sky
3-4 April 2020	Venus passes through the Pleiades cluster
4 April 2020	Mercury close to Neptune
8 April 2020	Perigee Full Moon ("super" Moon), 3:10 am
15 April 2020	waning Moon close to Jupiter in the morning sky
16 April 2020	waning Moon close to Saturn in the morning sky
22 April 2020	Crescent Moon close to Mercury in the morning sky
26-27 April 2020	Crescent Moon near Venus in the evening sky
May
5 May 2020	Eta Aquariid meteor shower
12 May 2020	Moon between Jupiter and Saturn in evening sky
15-16 May 2020	Mars near the waning Moon
22 May 2020	Mercury and Venus close
24 May 2020	Thin crescent Moon near Venus
June
6 June 2020	Penumbral lunar eclipse early morning near dawn
8 June 2020	Moon and Jupiter close in evening
9 June 2020	waning Moon and Saturn close in evening
13 June 2020	Moon and Mars close in morning
19 June 2020	Thin crescent Moon and Venus close in the morning twilight
July
5 July 2020	Jupiter close to the moon
6 July 2020	Moon and Saturn close
11 July 2020	Moon and Mars close in evening
12 July 2020	Venus close to bright star Aldebaran
14 July 2020	Jupiter at Opposition
17 July 2020	Thin crescent Moon near Venus in the morning
21 July 2020	Saturn at Opposition
29 July 2020	Southern Delta Aquarids meteor shower
August
2 August 2020	Moon between Jupiter and Saturn
9 August 2020	Moon close to Mars
15-16 August 2020	Crescent Moon close to Venus
28 August 20	Asteroid Ceres at opposition (binoculars only)
29 August 2020	Moon between Jupiter and Saturn again
September
5-6 September 2020	Mars close to the Moon
14 September 2020	Venus and crescent Moon close in morning sky
19 September 2020	Crescent Moon and Mercury close forming triangle with Spica
24 September 2020	Variable star Mira at its brightest
22 September 2020	Mercury and bright star Spica very close
22 September 2020	Earth at Equinox
25 September 2020	Waxing Moon, Jupiter form a triangle with Saturn
30 September 2020	Venus close to bright star Regulus
October
2-3 October 2020	Mars and waning Moon close
3 October 2020	Venus and the bright star Regulus very close
14 October 2020	Venus and the crescent Moon close
14 October 2020	Mars at opposition
18 October 2020	Mercury and thin crescent Moon closeish in the evening twilight
21 October 2020	Orionid meteor shower
22 October 2020	Jupiter and waning Moon close
23 October 2020	Saturn and waning Moon close
31 October 2020	Blue Moon in WA.
November
1 November 2020	Apogee Full Moon (mini-Moon). In WA full Moon occurs before midnight but for all states apogee is on the early morning of the 1st.
13 November 2020	Thin crescent Moon close to Venus
14 November 2020	Thin crescent Moon close to Mercury
18 November 2020	Leonid Meteor Shower
19 November 2020	Crescent Moon and Jupiter close forming triangle with Saturn
24-25 November 2020	Waxing Moon close to Mars
30 November 2020	Penumbral Lunar eclipse, only seen from eastern states. Blue Moon of all states except WA. (see above)
December
13 December 2020	Venus and thin crescent Moon close
14 December 2020	Geminid Meteor shower (New Moon, good rates)
17 December 2020	Jupiter and Saturn spectacularly close with the thin crescent Moon close too.
21 December 2020	Jupiter and Saturn even more spectacularly close in a conjunction that will not be repeated for over a decade. The pair will easily be visible together in telescope eye pieces.
21 December 2020	Earth is at Solstice
23-24 December 2020	Waxing Moon close to Mars

Labels: asteroids, Conjunction, eclipse, Jupiter, Mars, Mercury, Meteors, Opposition, Saturn, unaided eye, Venus, Yearly Sky Events

On the 11th of November UT (that's 11th-12th here in Australia), Mercury will transit the sun. While more common than transits of Venus, this will be the last until 2032.

Sadly, Australia will not get to see it (we will get to see the next in 2032 though). However, there are any number of live web-casts you can follow.



While these are all at horrible times here in Australia, if you are a late stayer or an early riser, you can catch a rare event.

Event	Universal Time	AEDST
Contact I	12:35:27	23:35 (11th)
Contact II	12:37:08	23:37 (11th)
Greatest Transit	15:19:48	02:19 (12th)
Contact III	18:02:33	05:04 (12th)
Contact IV	18:04:14	05:04 (12th)

Webcasts:
Time and date: https://www.timeanddate.com/live/
Space.com: https://www.space.com/mercury-transit-2019-viewing-guide.html
Vimeo: https://livestream.com/GriffithObservatoryTV/MercuryTransit2019
Royal Observatory: https://www.rmg.co.uk/discover/explore/when-is-the-next-transit-of-mercury

Labels: live-stream, Mercury, transit, webcast

The Moon and Saturn on 9 October 2019 at 04:00 ACDST, as seen form Alice Springs, the inset shows the telescopic view of the ringed world and the edge of the Moon just before occulation.  Most of northern Australia will enjoy similar views. Click to embiggen.

The table below shows significant astronomical events that can be seen with the unaided eye or minimal equipment in 2019 in Australia (and to some degree elsewhere in the Southern Hemisphere, ocultations and eclipses are very region specific).

Close pairings of the Moon and bright planets are given special attention as not only is the Moon a ready guide to locating the planets if you are not familiar with them, these massings are rather beautiful. 

Special events are bolded.

Sadly, the partial solar eclipse is just visible from parts of northern Australia, and the partial lunar eclipse is somewhat sad, but we have three occultations of Saturn and a number of beautiful planetary events to keep us occupied. The asteroid Vesta should be (just) visible to the unaided eye too.

Date	Event
2 January 2019	Venus close to crescent Moon in morning
3-4  January 2019	Crescent Moon and Jupiter close
4  January 2019	Crescent Moon near Mercury
12-13 January 2019	waxing Moon and Mars close
14 January 2019	Mercury a bit over a finger-width from Saturn low in the morning twilight
21 January 2019	Perigee Full Moon ("super" Moon, strictly at its biggest on the morning of the 22nd)
23 January 2019	Venus and Jupiter close in the morning
31 January 2019	Crescent Moon and Jupiter close again
1 February 2019	Crescent Moon close to Venus in the morning sky
2-3 February 2019	Crescent Moon close to Saturn in the morning
10 February 2019	Waxing Moon close to Mars
12-13 February 2019	Uranus close to Mars (binocular viewing)
20 February 2019	Perigee Full Moon ("super" Moon, strictly at its biggest on the evening of the 19th)
28 February 2019	Waning Moon close to Jupiter
2 March 2019	Crescent Moon close to Saturn in the morning
3 March 2019	Crescent Moon close to Venus in the morning sky
11 March 2019	Crescent Moon close to Mars
30 March 2019	Waning Moon close to Saturn
2-3 April 2019	Crescent Moon close to Venus in the morning sky
3 April 2019	Crescent Moon close to Mercury in the morning sky
9 April 2019	Moon close to Mars in evening sky
23 April 2019	waning Moon close to Jupiter in the evening sky
25 April 2019	Occultation of Saturn by the Moon, very low on horizon
4-25 May 2019	Asteroid Ceres visible in binoculars (opposition on 28th)
3 May 2019	Crescent Moon close to Venus in the morning sky
6 May 2019	Eta Aquariid meteor shower.
8 May 2019	Crescent Moon close to Mars
19 May 2019	Venus and Uranus a finger-width apart in the morning twilight (binoculars)
20 May 2019	Jupiter near waning Moon
22 May 2019	Waning Moon close to Saturn
1-29 June 2019	Asteroid Ceres visible in binoculars
2 June 2019	Crescent Moon and Venus close in twilight
4 June 2019	Crescent Moon and Mercury close
5 June 2019	Crescent Moon and Mars close
11 June 2019	Jupiter at Opposition
16 June 2019	Jupiter and Full Moon close
19 June 2019	Moon and Saturn close
4 July 2019	Mercury close to Crescent Moon and Mars in the twilight
10 July 2019	Saturn at Opposition
13-14 July 2019	Moon and Jupiter close
16 July 2019	Moon and Saturn close
16-17 July 2019	Partial Lunar Eclipse, early morning, really only visible from WA and a bit in the Central states
30 July 2019	Southern Delta Aquarids meteor shower
10 August 2019	Moon close to Jupiter
12 August 2019	Moon close to Saturn, Occultation seen on East coast only
6 September 2019	Waxing Moon and Jupiter close
8-9 September 2019	Saturn close to Moon, Occultation in northern and Western Australia
13 September 2019	Apogee Full Moon (mini-Moon)
29 September 2019	Mercury close to bright star Spica
30 September 2019	Crescent Moon close to Spica and Mercury with Venus below
3-5 October 2019	Venus and the bright star Spica close
4 October 2019	Jupiter and waxing Moon close
6 October 2019	Saturn and waxing Moon close
22 October 2019	Orionid meteor shower
24 October 2019	Variable star Mira at its brightest
29 October 2019	Mercury, Venus and Crescent Moon close
31 October 2019	Jupiter and waxing Moon close
2 November 2019	waxing Moon close to Saturn
9 November 2019	Jupiter crescent Moon close
11 November 2019	Crescent Moon and Saturn close
12 November 2019	Asteroid Vesta at opposition, potentially (just) visible with the unaided eye
17 November 2019	Leonid Meteor Shower
24 November 2019	Jupiter and Venus just two finger-widths apart
25 November 2019	the Crescent Moon, Mars and Mercury form a triangle in the dawn sky
28-29 November 2019	the Crescent Moon, Jupiter and Venus form a line in the evening twilight
2 December 2019	Venus close to the globular cluster M22 in the evening twilight (binocular)
11 December 2019	Venus and Saturn two finger-widths apart
15 December 2019	Geminid Meteor shower (full Moon, poor rates)
23 December 2019	Crescent Moon close to Mars in morning sky
26 December 2019	Partial Eclipse of the Sun, visible only in northern Australia
27 December 2019	Crescent Moon close to Saturn in the evening twilight
29 December 2019	Crescent Moon close to Venus in the evening sky

Labels: asteroids, Conjunction, eclipse, Jupiter, Mars, Mercury, Opposition, Saturn, unaided eye, Venus, Yearly Sky Events

Venus seen in the twilight above the ocean at 20:08 ACDST. Taken with a Canon IXUS 400 ASA 1/20 minute exposure. Click to embiggen to see Venus clearly.	Enlarged crop of the area to show location of Mercury. Venus uis the bright dot above Mercury

I have been able to see Venus for about a week (more due to the weather and clouds than due to its actual visibility), and yesterday was a good opportunity to see Venus and Mercury together. Sadly, although Veus was readily visible to the unaided eye 30 minutes after sunset, Mercury is still invisible without binoculars (it did {just] show up in the photos). Venus will become more prominent over the next weeks, with a nice encounter with the thin crescent Moon on the 19th. Mercury never gets better this month.

Labels: astrophotography, Mercury, unaided eye observation, Venus

Labels: asteroids, comet, Conjunction, eclipse, Jupiter, Mars, Mercury, Opposition, Saturn, unaided eye, Venus, Yearly Sky Events