CAS Sky Notes for October 2024

Autumn and the dark skies are now well upon us. 

***Comet Tshuchinshan-ATLAS***

This could potentially become very bright.  Look low in the west after sunset from the 10th October when it is first observable.  Its elongation from the Sun will increase each night.  The 12th is a good time to look.  We hope it survives its close approach to the Sun and puts on a good display throughout October.

Annular Solar Eclipse

This takes place on the 2nd October, but you’ll need to go to the South Pacific Ocean or southern Chile I’m afraid.

Planets

Mercury

Mercury will not really be observable this month

Venus

Venus is an evening object with a magnitude of – 4.0.  Its elongation increases to 37o, with a phase of 75%, and a diameter of 14”.  Its southerly declination also makes it hard to view as it is low in the sky after sunset, but can be seen if you have a good western horizon.

Mars

This is in Gemini but still effectively a morning object, although it rises a little before midnight now.  Its diameter increases a bit to 9 arcsec during the month and is high in the sky.  Its approximate position is RA 7h 35m, Dec +22o, and its red colour and the fact that it won’t be twinkling (planets don’t twinkle) will make it easy to identify.

Jupiter

This rises around 9pm now and is well placed for observing later in the night.  It reaches opposition in December. It is unmistakable, with a magnitude of -2.6, so stay up and get observing!

Saturn

Saturn reached opposition in September.  The rings have a tilt of about 5o by the end of the month.  This could make a nice photo.  It is still a bit low in the sky but is a little brighter due to more of the rings showing (mag.0.7).  Look for Titan, its brightest and biggest satellite which orbits every 16 days.  On 14th October Saturn is just 0.1o South of the Moon.

Uranus

Uranus is observable for much of the night (RA: 3h 36m, Dec +18o).  It reaches opposition in November. Its magnitude is +5.6 and diameter 3.8”.

On the 19th, The Moon will be between the Pleiades and Uranus.

Neptune

Neptune reached opposition on 21st September, with a diameter of 2.4” and mag. +7.8.

Its approximate position is RA 23h 54m, Dec -2.2o. On the 15th, Neptune is about 0.6o south of the Moon.  This should make it easier to find.

Anyone wishing to Uranus and Neptune, and who would like more details, should contact me at coord@cotswoldas.org.uk

Moon

 2nd   October:  New Moon                  10th October:  Moon is at First Quarter

17th October:  Full Moon                    24th October:  Moon is at last quarter

   The Full Moon on the 17th  is a good Supermoon to view

 Sun

The Sun remains active currently, so watch out for large Sunspot groups.  Remember to never look at the Sun directly without a proper solar filter.

Aurora

The Sun is around its maximum activity and may produce more aurorae.  I suggest you download an aurora alert App, such as Aurora Pro.  The darker nights mean that there is a much better chance of seeing them.

Meteors

The Orionids become visible this month, reaching their maximum around the 20th. Unfortunately, that is just after full Moon, making this display less favourable.  The radiant is near the top of Orion (hence the name) and the ZHR is about 20, so not many each hour.

Dark Sky Objects

The Milky Way is well placed for photography and the Andromeda Galaxy (M31) is high in the sky, making it a good target for photography.  A wider angle shot could take in the Milky Way as well.

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CAS Sky Notes for September 2024

The nights are now getting much longer after our ‘summer’. We reach the autumnal equinox on the 22nd September.

Partial Lunar Eclipse

There will be a ‘slight’ partial eclipse of the Moon on September 18th. The maximum magnitude of the Moon in the umbral shadow is 0.085, so just a bit at the top right corner.

It is also, of course, a long penumbral eclipse.  The times are given below (converted to BST from UT). P1 refers to the start of penumbral phase, P4 the end. U1, onset of umbral phase and U4 the end.  Greatest eclipse occurs at 03:45 BST.  All times below are BST.

P1= 01:41        U1 = 03:12       U4 = 04:15       P4 = 05:47

Planets

Mercury

Mercury has moved into the morning sky and reaches greatest western elongation, of 18o,  on the 5th September.  Its northerly declination makes it higher in the sky and therefore easier to find.   This is a good opportunity to view this planet if you are willing to get up before dawn!  The diameter is around 7 arcsec at that stage and the phase 50% (of course I should add).  

Venus

On the 5th, Venus will be 1.2o  N of the Moon, which is only 2 days old.   Venus is now an evening object with a magnitude of – 3.9.  It’s elongation increases to 30o, with a phase of 85%, and a l diameter of 12”.  It’s southerly declination also makes it a tricky object to view this month.

Mars

This is still effectively a morning object, although it rises a little after midnight now.  Its diameter increases a bit to 7.5 arcsec during the month and is high in the sky.  Its approximate position is RA 6h 30m, Dec +23o, and its red colour and the fact that it won’t be twinkling (planets don’t twinkle) will make it easy to identify.

Jupiter

This rises before midnight now and is well placed for observing.  It reaches opposition in December. It is unmistakable, with a magnitude of -2.4, so stay up and get observing!

Saturn

Saturn reaches opposition on September 8th.  The rings have a tilt of about 3o and so are  nearly edge on.  This could make a nice photo.  It is still a bit low in the sky and not very bright (mag. 0.6) mainly because the rings are not contributing to its magnitude.  Look for Titan, its brightest and biggest satellite which orbits every 16 days.  While looking at it, remember that the Huygens probe landed on it back in 2005.

Uranus

Uranus is observable in the late evening (RA: 3h 39m, Dec +18.5o).  It reaches opposition in November. Its magnitude is +5.6 and diameter 3.8”.

Neptune

Neptune reaches opposition on 21st September, with a diameter of 2.4” and mag. +7.8.

Its approximate position is RA 23h 58m, Dec -1.8o.

Anyone wishing to observe them and who would like more details should contact me at coord@cotswoldas.org.uk

Moon

 3rd  September:  New Moon              11th September:  Moon is at First Quarter

18th September:  Full Moon               24th September:  Moon is at last quarter

 Sun

The Sun is remains active currently, so watch out for large Sunspot groups.  Remember to never look at the Sun directly without a proper solar filter.

Aurora

The Sun is around its maximum activity and may produce more aurorae.  I suggest you download an aurora alert App, such as Aurora Pro.  The darker nights mean that there is a much better chance of seeing them.

Meteors

There are no major meteor showers this month, but you could watch out for the September ε Perseids during around the 9th of the month. Radiant position is RA 3h 16m Dec. +39o.

The Zenithal Hourly Rate (ZHR) is only about 5, but some years they give a much better display.

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M6 & M7 from Chedworth

By James Weightman

The picture was taken on the 20th June. Taking advantage of a clear southern sky from the disused airfield at Chedworth and despite the nearby full moon and the very low altitude, I managed to capture some of the southernmost Messier objects.

Messier objects M6, the Butterfly Cluster (NGC 6405) and M7 Ptolemy Cluster (NGC 6475) are visible in the picture.

The insets were 5-minute stacks taken with Seestar superimposed on an earlier image which also managed to capture the stars of the scorpion’s sting.

 

CAS 2024 Annual Photographic Competition Winners

It was announced at the last meeting, on the 12th August 2024, which photos were judged by the membership to be the winners of the Aesthetic and Technical categories.

With a total of 24 entries, all of very high quality, (viewable HERE), the votes produced clear winners. Susan Snow was the winner of the Aesthetic category, with her photo Moon Rise.

The winner of the Technical category was Tim Jackson, with his photo of Comet 12P/Pons-Brooks “Mother of Dragons”.  With a total of 26 votes this also makes Tim the overall winner and recipient of the Dan Turton Trophy, to be presented at the September meeting.

The Committee would like to extend our thanks all those who entered and for making the competition very interesting indeed. Entries for the next competition will need be submitted in March next year so all members are encouraged to see what they can do before then. We will all be looking forward to it.

Perseids and the UK Meteor Radar Project

The UK Meteor Beacon has been operational since May 2022 enabling anyone with a suitable receiver to detect and study radio echoes from meteors entering the earth’s atmosphere over a large part of the UK. The Beacon Transmitter is located at the Sherwood Observatory of the Mansfield and Sutton Astronomical Society.

The second phase of this project has been to establish a network of receivers accessible via the internet for anyone to study meteors without the need for their own dedicated receiver. “The UK Meteor Radar Project” is a Bi-Static radar to study meteors.

Receivers in the network stream their data to a central server which users can access. Up to 6 receivers are displayed at https://ukmeteorbeacon.org/beaconclient/ . Details of how to use the display can be found at the project web site:- https://ukmeteorbeacon.org/Home see “Observing GB3MBA” and the live displays are explained at https://ukmeteorbeacon.org/Documents2List . Select “Using the Live Streams”.

We aim to maintain the live stream at https://ukmeteorbeacon.org/beaconclient/ 24/7 and during the Perseids this August we will provide an additional stream which has greater bandwidth and includes sound. This can be viewed at https://batc.org.uk/live/gb3mba. Again the “Using the Live Streams” document explains the display.

Individuals or societies observing the Perseids will find these live streams of radio echoes a useful addition to their optical observations. The radio echoes can be viewed by day and night and in all weather conditions.

CAS Sky Notes for August 2024

The summer evenings are getting shorter now and the skies get dark noticeably earlier throughout the month

Noctilucent Clouds

Do continue to watch out for them and try to photograph them if possible.

Aurora

The Sun is around its maximum activity and may produce more aurorae.  I suggest you download an aurora alert App, such as Aurora Pro.  The darker nights mean that there is a much better chance of seeing them.

Planets

Mercury

It is still visible for the first week of August, having reached greatest eastern elongation on the 22nd July.  Its northerly declination means it should be easier to find after sunset.  This is a good opportunity to view this planet throughout the month.  The diameter is around 10 arcsec for the first week and the phase drops from 35% to 15%.

This is an elongation worth observing!

Venus

Venus is now an evening object with a magnitude of – 3.8.  However, it has an elongation of only about 18o, a phase of 95%, and a small diameter of 10.5”.  It isn’t an easy object yet.

Mars and Jupiter

These are still both morning objects and can be viewed an hour or two before sunrise.

However, on the 14th August they are at conjunction and only 20 arc minutes (0.33o) apart.  They should be visible in the same field of view of a small telescope and this could make a nice photo opportunity!

Saturn

This is now moving into the evening sky as it approaches opposition on September 8th.  The rings have a tilt of less than 3o and so are getting near to edge on.

Uranus and Neptune

These are still morning objects,

Anyone wishing to observe them and who would like more details should contact me at coord@cotswoldas.org.uk

Moon

 4th August:  New Moon          12th August:  Moon is at First Quarter

19th August:  Full Moon          26th August:  Moon is at last quarter

 Sun

The Sun is remains active currently, so watch out for large Sunspot groups.  Remember to never look at the Sun directly without a proper solar filter.

Meteors

This month sees the peak of the Perseid meteor shower which reaches its maximum on the 12th August.  The Zenithal Hourly Rate (ZHR) can exceed 80. Perseus is in the northeast in the late evening.  The radiant is around RA 3h 11m and Dec +58o, but the meteors can be seen across the sky, appearing to come from that point.

The Moon is at first quarter and therefore sets around midnight.  That is the best time to start looking for the meteors.  Be sure to let your eyes get dark adapted for at least 15 minutes and don’t look at your phone, as that will destroy your night vision for another 15 minutes!

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CAS Sky Notes for July 2024

I apologise for the late arrival of these notes.  Entirely the fault of your Coordinator!

The summer solstice has just passed, but skies are too light too late for any deep sky astronomy.  Astronomical twilight still lasts all night, so there will be a permanent glow in the north, even at midnight.

Noctilucent Clouds

July is a good time to look out for these in the northwest an hour or so after sunset. They occur when fine dust particles in the very high atmosphere form ice crystals around them.  These reflect sunlight still shining at those altitudes. They can appear electric blue/white.

Do watch out for them and try to photograph them if possible.

Aurora

The Sun is around its maximum activity and may produce more aurorae.  I suggest you download an aurora alert App, such as Aurora Pro.  The nights may be a little too bright for great displays, but by the end of the month the nights are getting longer, so keep an eye out.

Planets

The only planet visible in the evening sky this month is Mercury

It reaches greatest eastern elongation on the 22nd July and will be 27o east of the Sun.  Its northerly declination means it should be easier to find after sunset.  This is a good opportunity to view this planet throughout the month.  The diameter on the 4th is 5.9” (arc sec) with a phase of 73% (gibbous).  By the 22nd, its diameter is 8“ and the phase is 50%.

This is an elongation worth observing!

The other planets are still morning objects, but increasing their elongation from the Sun and therefore easier to view.  Anyone wishing to observe them and who would like more details should contact me at coord@cotswoldas.org.uk

Moon

 5th July:  New Moon                13th July:  Moon is at First Quarter

21st July:  Full Moon               28th July:  Moon is at last quarter

 Sun

The Sun is rather active currently, so watch out for large Sunspot groups.  Remember to never look at the Sun directly without a proper solar filter.

Meteors

This month sees the start of the Perseid meteor shower which reaches its maximum around mid August.  Try to catch some early ones.  The radiant is around RA 3h 11m and Dec +58o

 

To view this post in PDF format please CLICK HERE

Sunspot grouping

by James Weightman

Huge Sunspot Group

Sunspots are dark regions on the surface of the Sun that appear darker than the surrounding area. They are caused by strong magnetic fields that emerge through the photosphere, or surface, of the Sun.

Sunspots consist of two main regions:
the Umbra: a central dark region, which is cooler (about 3500°C) compared to the surrounding photosphere (about 5,500°C),
and the Penumbra: the surrounding region that is also cooler and lighter.

On average, sunspots are about the same size as Earth, although they can vary significantly in size from hundreds to tens of thousands of miles across; a group of sunspots as seen in these photos is known as an ‘active region’.

The frequency and intensity of sunspots visible on the Sun’s surface indicate the level of solar activity during the 11-year solar cycle which is driven by the Sun’s magnetic field. Sunspots play a significant role in generating solar flares and coronal mass ejections (CMEs), which can impact space weather and Earth’s environment.