Hi all,
1. IAA LECTURE SEASON: Opening Lecture, Wednesday 17 September, 7.30 p.m. Larmor Lecture Theatre, Physics Building, QUB
"Jewels of the JWST: How the Webb Telescope is Changing Our Understanding of the Universe" by Prof Tom Ray, DIAS.
Abstract: Since the James Webb Space Telescope has started operating it has challenged and enriched our understanding of how fast the Universe is expanding, how galaxies emerge earlier than we thought, and the diverse composition of planet forming disks. In this talk I will explain many of these exciting discoveries and the new synergies between the Webb and cutting-edge ground based telescopes.
BIOG: Prof Ray is one of Ireland's leading astronomers, with a very lengthy CV: He is Senior Professor of Astronomy at the Dublin Institute of Advanced Studies, and a Principal Investigator on the amazingly successful MIRI Instrument on the JWST.
We have been honoured to have many superb lectures from him before, so this is one not to be missed!
Admission free, including light refreshments. All welcome.
2, SUBSCRIPTIONS DUE, 1 September
After many many years of keeping the subs constant at £20 we have reluctantly had to raise the amount to £25, to cover rising costs. Student membership is only £10. Details on the IAA website https://irishastro.org/
Please amend your payment details accordingly. If you have already paid at the old rate, please add an extra £5 via Paypal or whatever is convenient.
3. NEW INTERSTELLAR VISITOR FOUND.
It's official! An interstellar object is visiting our solar system
With an absolute magnitude of about 12, it will be interesting to see how much it brightens as it nears perihelion. We may get our best view as it moves out from the solar glare in December, and gets closest to Earth, although even then it will be about 1.6 AU away.
LATEST – Here's A Photo Telescope spies rare interstellar comet 3I/ATLAS zooming through our solar system (photos)
Latest, from Dan Fisher - It is going to reach a magnitude of 6 in late October, although it will be very close to the Sun (I wonder? – this goes against other predictions!).
There is now also a CBET about 3I/ATLAS:
http://www.cbat.eps.harvard.edu/iau/cbet/005500/CBET005578.txt - it gives the comet as 13th magnitude after perihelion, in November with the elongation around 60°.
Please ignore all the media speculation about this being an alien artefact: just Avi Loeb off on his favourite hobby-horse again. - As Prof Chris Lintott told me recently 'It's nonsense on stilts!'
Since this is the first chance any of us will have had to see a non-stellar object from outside our solar system, I'm giving the following details for initial planning. No doubt more accurate details will be available in due course:
Epoch = 2025 Oct. 12.0 TT
T = 2025 Oct. 29.41062 TT Peri. = 127.93850
e = 6.1801697 Node = 322.18759 2000.0
q = 1.3620397 AU Incl. = 175.11382
(Note that the inclination is much more than 90 degrees – almost 180, in fact. This means that it is travelling round the Sun in almost the opposite direction to all the planets.)
The following ephemeris is from the above orbital elements, and uses photometric power-law parameters H = 9.5 and 2.5n = 8 for the magnitudes. (Delta is distance from Earth, and r (Radius Vector) is distance from the Sun, both in AUs). Elong is angular elongation from the Sun.
There are no figures from 22 Sep to 21 November, when it will be too close to the Sun for easy observation. But perhaps more information will be obtainable closer to the 'Superior Conjunction' date, based on the latest observations.
Date TT R. A. (2000) Decl. Delta r Elong. Phase Mag.
2025 09 07 15 15.46 -13 46.3 2.563 2.341 65.9 23.1 14.5
2025 09 12 15 04.25 -13 10.8 2.552 2.197 58.3 22.9 14.3
2025 09 17 14 53.51 -12 35.0 2.542 2.059 50.8 22.2 14.0
2025 09 22 14 43.19 -11 59.1 2.531 1.928 43.3 20.9 13.8
2025 11 21 12 34.09 -02 22.3 2.040 1.593 49.8 28.3 12.7
2025 11 26 12 18.72 -01 01.8 1.978 1.694 58.9 29.9 12.8
2025 12 01 12 01.83 +00 27.9 1.920 1.808 68.4 30.5 13.0
2025 12 06 11 43.30 +02 06.8 1.871 1.932 78.4 30.0 13.1
2025 12 11 11 23.10 +03 54.3 1.833 2.063 88.8 28.5 13.3
2025 12 16 11 01.34 +05 48.4 1.811 2.202 99.7 26.1 13.5
2025 12 21 10 38.31 +07 45.8 1.808 2.345 110.8 23.1 13.7
2025 12 26 10 14.50 +09 42.1 1.828 2.493 122.1 19.5 14.0
2025 12 31 09 50.52 +11 32.4 1.872 2.645 133.3 15.7 14.2
2026 01 05 09 27.06 +13 12.7 1.941 2.799 144.3 11.8 14.5
2026 01 10 09 04.75 +14 40.1 2.035 2.956 155.0 8.1 14.8
2026 01 15 08 44.07 +15 53.7 2.153 3.114 165.1 4.6 15.1
2026 01 20 08 25.34 +16 53.8 2.293 3.274 174.5 1.7 15.4
2026 01 25 08 08.70 +17 41.8 2.454 3.436 175.2 1.4 15.7
2026 01 30 07 54.15 +18 19.6 2.632 3.599 167.0 3.5 16.1
4 (Almost) Total Lunar Eclipse, 7 September
We will only just miss totality, as it ends at 18.52 UT (19.52 B/IST), and the Moon rises just a few minutes later. Obviously, the further East you are, the earlier the Moonrise, so we may plan an observing event (weather permitting), along the Co Down coast near Ballyhalbert. But note that, by definition, the eclipsed Moon is opposite to the Sun in the sky, so the Moon will rise in bright twilight, thus the eclipse may not be all that easy to see at first! Details in the IAA website
The further West you are, the more the Moon will have come out of totality before it rises. But even so, this will be a deep partial eclipse all over Ireland. The partial phase ends at 20.56 , and the penumbral phase ends at 21.55, both B/IST
5. ISS
The ISS will start a new series of evening passes on 10 September. Details for your location are available on www,heavens-above.com
6 The Moon occults. the Pleiades on September 12, but just as it rises, so not easy to see. The following details are for disappearance for Belfast; times will vary slightly elsewhere in the island. TIMES are Summer Time
Electra (17 Tau, mag 3.7) at 21.24 (Alt = 2.4 deg
Merope (23 Tau, mag 4.2) at 21.47 (Alt = 4 deg)
Alcyone (Eta Tau, mag 2.8) at 22.12 (Alt = 7 deg)
Pleione (20 Tau, mag 4.7 – 5.5v) at 22.50
Atlas (27 Tau, mag 3.6) at 22.53
Reappearances will be about an hour later, at the dark limb, so a bit easier to see.
7. VENUS, JUPITER and SATURN VISIBLE IN MORNING SKY
Our sister planet is now visible low in early morning twilight in Cancer, Jupiter is higher up in Gemini. Saturn is well placed with opposition on Sep 21, in Pisces..
8. WhatsApp Group for alerts on Observing Nights.
The IAA have set up a WhatsApp Group for updates on Observing Nights. If you would like to be included in this group, please e-mail Mary at callistoboxers@hotmail.com with your full name & mobile telephone number.
No discussions about anything other than Observing Nights will be posted on this group.
9. WORLD SPACE WEEK, 4 – 10 October Irish events will be co-ordinated by BCO in Cork.
10. October 4: International Observe the Moon Night
11. ALAN 2025, 28 – 30 October 2025, Westport, Co.Mayo.
Preparations are under way for the 9th Scientific Conference on Artificial Light At Night, ALAN2025, from October 28-30, 2025, in Westport, Ireland. Our host will be Dark Sky Ireland. The invited speakers will be revealed soon, but we can already promise you interesting talks about science, governance, dark sky outreach, and lighting design.
The conference offers a platform for interdisciplinary networking and exchange on the topics Biology & Ecology, Governance & Regulations, Health, Measurements & Modelling, Social Sciences & Humanities, Technology & Design.
We welcome researchers, lighting professionals, policy makers, light pollution activists, and everybody who is interested in the effects of artificial light at night. The conference aims to present new findings, exchange experiences and ideas, network, and discuss hoe artificial light can be used with less negative impacts.
I'm on the organising committee for this event, so I'll keep you posted regarding the programme.
For more information check out our website at artificiallightatnight.org .
This event will be followed immediately by the wonderful Mayo Dark Sky Festival in nearby Newport –
12: Mayo Dark Sky Festival, 31 October – 2 November. More details later.
13. CAP May 2026, Armenia:
As the only large-scale international conference dedicated to astronomy communication, CAP gathers science communicators, educators, planetarium professionals, journalists, astronomers, and creatives to explore the best ways to share astronomy with diverse audiences. Whether you work in outreach, media, museums, or informal education, CAP is where you'll find inspiration, fresh perspectives, and a welcoming global community.
The next CAP Conference will happen in May 2026, hosted by the Byurakan Astrophysical Observatory and the Armenian Astronomical Society, in-person in Yerevan, Armenia, and online. This hybrid format ensures that participants from all corners of the world can take part in the discussions, workshops, and networking opportunities.
Organised by IAU Commission C2 and the IAU Office for Astronomy Outreach, CAP 2026 promises to be an unmissable event. If you're passionate about bridging the gap between science and society, this is your chance to connect, learn, and contribute to the future of astronomy communication.
14: 2026 Eclipse planning.
This may be of interest to those planning observing locations for the total solar eclipses in 2026 and 2027
Global risk map reveals the most dangerous countries and cities
And weather prospects for the coming eclipses such as the one in Spain in 2026, and N. Africa in 2027, are on www.eclipsophile.com . The discussions there will help you pick a site for the eclipse, as weather is one of the important factors to consider.
15: Recurrent Nova T Corona Borealis – We're still waiting!
It's well over a year now since the first predictions of an 'imminent' outburst! But, it could explode any time, so, keep an eye on it - comparison charts can be found on the websites of the BAA Variable Star Section, or the AAVSO. The current magnitude is around 10, so you'll need a good telescope to see it now.
(BTW, don't confuse it with the other nearby famous variable star, R CrB, which does the opposite – it stays normally around 6th magnitude, but occasionally dims to as faint as magnitude 14 or 15!)
Anyway, do keep an eye out – T CrB lies just outside the East side of the circle of the 'Crown', about a degree from Epsilon CrB, but you really do need charts to observe it properly. It's now visible in the sky in the East each night before midnight.
It's at Declination: 25° 55′ 12.613″; R.A.: 15h 59m 30.1622s)
16: New EASY TEASER:
What's next in this sequence – I've now added yet another one - What's next after Sirius:?
1. Aldebaran, 2. Rigel, 3. Capella, 4. Betelgeuse, 5. Sirius. 6…..,?
Clue: It's Right….
Final clue: what system to astronomers use to measure position in the sky?
17: New DIFFICULT TEASER:
Where in astronomy would you find the following sequence of letters (ignoring variable stars) - "Z Z"
Clue: Note the space between the letters.
Another clue: What's in a name?
One more clue: there are other letters involved, before the first one, and after the second one.
Final Clue: An astronomer.
Remember, send answers to me only at my aol address: terrymosel@aol.com.
18. INTERESTING WEBLINKS (Disclaimer – Use of material herein from various sources does not imply approval or otherwise of the opinions, political or otherwise, of those sources). NB: If the title in the weblink does not indicate the subject matter, I give a brief simple intro before the link. I may also comment about the link afterwards.
ASTROPHYSICS:
Astronomers discover a 'forbidden' pulsar fleeing a supernova in a seemingly empty region of the Milky Way | Space JWST May Have Found the Universe's First Pristine Galaxy BlueDOGs Might Evolve From Little Red Dots - Universe Today Astronomers Just Discovered The Milky Way's Heaviest Stars
That mysterious 'Wow! signal' from space? Scientists may finally know where it came from — and it's probably not aliens
Supernovas are hard to detect. Scientists just found a way to spot them hours after they explode
Oops! Earendel, most distant star ever discovered, may not actually be a star, James Webb Telescope reveals
A Massive Virtual Radio Telescope Spots A Ribbon-like Jet Of Super-heated Plasma - Universe Today
Black hole mapped https://share.google/WyYm7vPkQ2vslx3iz
COSMOLOGYStudy: Dark matter doesn't exist, the universe is 27 billion years old - Earth.com
A new theory of the universe's origins without inflation The Universe's Engine Is Changing: DESI Hints Dark Energy Isn't What We ThoughtNew Theory Casually Upends Space and Time | Universe Theories
EARTH & MOONThis Startup Is Racing To Be The First To Mine Helium On The Moonhttps://phys.org/news/2025-09-radio-astronomy-laser-earth-axis.html US in real danger of losing the moon race to China, experts tell Senate | Space
EXOPLANETSTESS reveals two rocky Earth-sized exoplanets orbiting nearby K-type star 'A remarkable discovery': Astronomers find 1st exoplanet in multi-ring disk around star
LIGHT & SATELLITE SKY POLLUTIONSatellite Companies Like SpaceX Are Ignoring Astronomers' Calls to Save the Night Sky
NASANASA once celebrated her, then fired her, and then tried to erase her story: The rise and fall of Rose Ferreira | - The Times of India SOLAR SYSTEM Pluto's dwarf planet partner Charon may have spilled its guts to create 2 of the pair's moons | Space Rare Chi Cygnids are active! Maybe. Observing info here Possible peak on Sep 13-15.Interstellar invader comet 3I/ATLAS could be investigated by these spacecraft as it races past the sun: 'This could be literally a once-in-a-lifetime opportunity' | Space Mars' interior might contain remnants of baby planets The interstellar comet 3I/ATLAS is wrapped in carbon dioxide fog, NASA space telescope reveals | Space TESS spotted 3I/ATLAS two months before it was discovered. It was even active then
Scientists Have Uncovered When Jupiter Was Born, Solving a Longstanding Mystery 3I/ATLAS Is Very Actively Releasing Water - Universe Today https://share.google/l3IrCGW7TQOQfSXbN
3I/ATLAS's Coma Is Largely Carbon Dioxide - Universe Today
Strange blobs found inside Mars could be remnants of something ancient, astronomers say
SPACEFirst Irish-designed satellite Eirsat-1 to fall from orbit and burn up this week | Irish Independent We had a great lecture from Lorraine about this satellite several years ago.SpaceX Dragon cargo capsule boosts ISS higher above Earth in key test | SpaceUS in real danger of losing the moon race to China, experts tell Senate | Space
NASA's new sun-studying mission 'PUNCH' attains its final form in Earth orbit
TELESCOPES, INSTRUMENTS, TECHNIQUES
This Weirdly Brilliant Telescope Design Might Finally Uncover Earth's Twin
FINAL WORD:
"The treasures hidden in the heavens are so rich that the human mind shall never be lacking in fresh nourishment." - Johannes Kepler
19. JOINING the IRISH ASTRONOMICAL ASSOCIATION. This link gives options to join the IAA.
https://irishastro.org/join-the-iaa/ If you are a UK taxpayer, please select the 'gift-aid' box, as that enables us to reclaim the standard rate of tax on your subscription, at no cost to you. You can also make a donation via Paypal if you wish: just click on the 'Donate' button. See also https://irishastro.org/
The Irish Astronomical Association is registered with The Charity Commission for Northern Ireland NIC 105858
DISCLAIMER: Any views expressed herein are mine, and do not necessarily represent those of the IAA.
Clear skies,
Terry Moseley
