Cotswold Astronomical Society

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.

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.

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 22^nd 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 18^o, 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 14^th August they are at conjunction and only 20 arc minutes (0.33^o) 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 8^th.  The rings have a tilt of less than 3^o 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

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

19^th August:  Full Moon          26^th 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 12^th 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 +58^o, 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!

To view this post in PDF format please CLICK HERE

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 22^nd July and will be 27^o 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 4^th is 5.9” (arc sec) with a phase of 73% (gibbous).  By the 22^nd, 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

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

21^st July:  Full Moon               28^th 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 +58^o. 

 

To view this post in PDF format please CLICK HERE

The photos submitted for the annual photo competition are now available to view.

Please CLICK HERE

by James Weightman

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.

by Susan Snow

By Peter Cadogan.

I will be presenting at the European Lunar Symposium 16th-21st June 2024.  https://sservi.nasa.gov/els2024/

This article is available for members to view in the Mercury section. 

Extract:

Introduction: Lunar craters as small as 2.5m in diameter have been counted at many sites  cross the lunar surface, mainly mare ones [1]. The very large counts allow them to be plotted as size frequency histograms (CSFH), rather than cumulative distributions, enabling  subtle differences between sites to be more clearly revealed. The results for the ejecta blanket of Giordano Bruno crater, combined with current cratering rates determined by temporal imaging [2], are consistent with its age being about 10Ma [3], confirming that even  the very smallest craters formed during this period still exist today.

The summer solstice occurs on the 20^th June and skies are too light too late for any deep sky astronomy.  Astronomical twilight now lasts all night, so there will be a permanent glow in the north, even at midnight.

Aurora

Hopefully many of you saw the recent display of Aurora, courtesy of a huge sunspot group on the Sun emitting flares and a Coronal Mass Ejection (CME).

It was a magnificent sight and so rare to see anything like that at these latitudes.  We were blessed with, not just a green glow in the north. But reds and blues and pinks bursting overhead.  It is possible that there may be more displays if the sunspot group remains.  Also, the Sun is around its maximum activity and may produce more aurorae.  Keep an eye out and maybe download an aurora alert App, such as Aurora Pro.

Planets

There are no planets visible in the evening sky this month.  There is an alignment of the planets in the morning sky of June 3^rd before sunrise.

Of course, they are not really anywhere near each other, but the alignment is pretty.

Venus is not visible as it reaches superior conjunction (behind the Sun) on the 4^th June.  Also, Uranus and Neptune require a telescope to be seen.

Mercury also reaches superior conjunction on the 14^th June.

 

Moon

 6^th June:  New Moon              14^th June:  Moon is at First Quarter

22^nd June:  Full Moon              28^th June:  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

June Bootids.  June 22^nd to 2^nd July. These occasionally have outbursts, so watch out for them.

 

To view this post in PDF format please CLICK HERE

The CAS Coordinator’s annual report, the Treasurer’s written report and statement of accounts is now available for members to view in the member’s only part of this website. Any questions should be submitted to the Coordinator in advance of the AGM on Saturday 11th May 2024.