1. Geminids
The Geminid meteor shower peaks on the night of December 13-14 with a ZHR of 100 - 120 meteors per hour. It is the richest and most spectacular shower of the year, with a high proportion of bright meteors Usually the brightest ones we see are about as bright as Sirius, the brightest star.
They get their name because they appear to come from an area in the sky, called the radiant, which is in Gemini. They can appear anywhere in the sky, but if you trace their tracks back they appear to come from a point near the star Castor, which is the second brightest of the 'Heavenly Twins'.
Gemini will be rising in the East in the early evening so rates won't be so high then. But the number of meteors seen will gradually increase as Gemini climbs higher into the sky, and moves round towards the South reaching its highest point about 2 a.m.
It's possible that we may also see one or two other meteors which are not part of that shower - they are called Sporadics, and can appear to come from any direction.
This year, the shower will be partly spoiled by a gibbous Moon. The Moon will set just after 3 a.m., so for the really keen observers, that will give dark skies until dawn, when the greatest rate of meteors will be seen - that could be up to about 80-100 per hour in a very dark location.
While the Moon is still in the sky, the best advice is to position yourself so that it's hidden behind a building or evergreen tree, or at least face in the opposite direction to the Moon. You usually see most meteors if you look a bit to one side of the radiant, and about halfway between the horizon and the overhead point. This year, that would be looking roughly North, to the left of Gemini, under the area of the Plough.
Geminids are generally fairly slow, and with a good proportion of bright events.
They are particularly interesting because the parent body is not a comet, as for most meteor showers, but an Asteroid called 3200 Phaethon.
Make sure to wrap up warm, and lie on something like a lounger to avoid straining your neck looking up at the sky for long periods.
The Zenithal Hourly Rate (ZHR) is the rate which would be seen by an experienced observer, in a VERY dark sky, and with the radiant in the zenith: actual observed rates very rarely reach the nominal ZHR for various reasons.
METEOR PHOTOGRAPHY:
If you have a digital SLR which can give longish time exposures, and you can manually focus it on infinity, and adjust it to a high ISO (film speed equivalent), you can image meteors with a bit of luck. Make a suitable lens hood, or heater, to prevent dew on the camera lens. You may also need a tripod.
Point the camera about 50° up in the sky, about 40° from the radiant, for best results. Consult your camera handbook, or experiment with exposures until the sky fogging becomes too severe.
2. Paul Evans's Video Sky Guide for December
Another one of Paul's excellent guides of what to see and how to see it: https://youtu.be/cihOElOBlFY
3. Venus becomes a bit more visible
As the angle of the ecliptic to the horizon in the early evenings slowly increases, Venus slowly climbs above the SW horizon in the twilight. It currently is almost in an equidistant line with Saturn and Jupiter, and although it's much lower down, its exceptional brightness makes it easier to see – although you have to catch it before it sets. It's mag -4.7, and if you can get it in a telescope you'll see that it's a moderate crescent, with a phase of 25%, and an apparent diameter of 42". It will remain low down in the SW, and fade only slowly, from now until Xmas.
4. Catch Saturn and Jupiter while you can.
SATURN: is moving further away from the Earth, and so it's fading and shrinking in apparent size. It's also very low from our latitude, so viewing conditions are not great. It's now mag 0.3, in Capricorn, with an apparent diameter of 18".
The angle of the ring system to Earth has been steadily decreasing recently, so the rings no longer extend beyond the poles. Aesthetically, I think this angle, and down to an angle of about 10 degrees, is the most beautiful.
Of the satellites, Titan is visible in any telescope, and Rhea is not too difficult. With the low altitude, it may be harder to see fainter Dione and Tethys, especially as they are closer to the planet. Big telescopes and good seeing are required for Enceladus and Mimas.
I've seen them all, using the 10-inch refractor at Armagh Observatory, and my own 37cm Newtonian, but when Saturn was a lot higher up, and in much less light-polluted skies!
Jupiter is also still reasonably visible from UK & Ireland, after its Opposition on August 20. It's in Capricorn, mag -2.3, some 17 degrees E of Saturn, and with an apparent diameter of 38". It's a bit higher up than Saturn, and that will gradually increase over the next few years.
The four big Galilean moons are visible in even a modest telescope. This year, the Sun and Earth are almost exactly in the plane of Jupiter's equator, so the moons pass backwards and forwards almost exactly in the plane of the planet's equator, so that's where the transits and shadow transits will appear.
5. Comet 2021/A1 (Leonard) is going! It looks it never brightened as much as expected, and is now sinking too low to be easily seen from Ireland
The website www.heavens-above.com gives finder charts and latest magnitude estimates, as well as lots of other observing information.
And here's one of several guides Comet Leonard on course for a good showing – Astronomy Now
BUT – see this Comet Leonard, the brightest of the year, is fading and acting strange | Space
6. Earliest Sunset, Belfast, Dec 13/14 Although the solstice won't be until Dec 21, the earliest sunset of the year at Belfast will be on December 13 and 14. On both days, the sunset will occur at 15h 57m 21s. Although my Skymap software does not give decimals of a second, I think that actual earliest date will be the 13th, but literally only by a fraction of a second!
The offset from the solstice of earliest and latest sunsets and sunrises is caused by the shifting values of the Equation of Time, mainly due to the Earth's elliptical orbit. You can Google that for more details!
This calculated time allows for 'standard atmospheric refraction', i.e. with atmospheric pressure of 1013mb, and a temperature of 10º C, which at an altitude of 0º amounts to 34', or more than a solar diameter. The actual amount of refraction depends on the local atmospheric pressure and temperature at the time. If it's high pressure, and very cold, the refraction will be greater, so the Sun will appear elevated slightly more above the horizon, and apparent sunset will be a bit later.
7. ISS:
The ISS will start a new series of morning passes on 20 December. Full details for your location on www.heavens-above.com, and on various Smartphone Apps
8. Solstice. The Sun will reach its most Southerly point along the ecliptic on December 21 at 15.58. This is very close to the time of local sunset, so the Sunset point will be almost as far South as it can ever be. As noted above, the actual amount of refraction depends on the local atmospheric pressure and temperature at the time. If it's high pressure, and very cold, the refraction will be greater, so the apparent azimuth of setting will appear slightly shifted towards the West.
9. Latest Sunrise, Belfast. This will occur on December 29, at 08h 46m 49s. The same caveats regarding refraction, as above, apply. Indeed, if the sky is clear at sunrise on a morning in late December it's probably going to be below 0º C, let alone 10º C, and the pressure is more likely to be high than low.
10. Ursids, 22 December. This shower, oft neglected because it's so close to Xmas, will be affected by the just past Full Moon. But you can get a few hours observing before the Moon rises at about 7.30 p.m. The normal ZHR is about 10, but there have been occasional outbursts, the last one being in 2014. The radiant is near Kocab, or Beta Ursa Minoris,
11. ESO Summer Research Programme 2022, ESO-HQ, Garching b. München, Germany / or virtually* 4th July - 12th August 2022 Applications open: 8th December 2021; Application deadline: 4th February 2022
The ESO Summer Research Programme provides a unique opportunity to students not yet enrolled into a PhD programme, to carry out a 6-week long research project at the ESO Headquarters in Garching (Germany)*. This fully-funded programme will allow the participants to choose between a wide range of research projects covering many areas of astronomy, from planet formation to cosmology. The ESO Summer Research Programme will also provide opportunities beyond research, including lectures, a mini-workshop, and social activities.
| * The ESO Summer Research Programme will be hosted in Garching if all accepted students are able to travel to ESO HQ. If the COVID-19 pandemic does not allow an in-person visit, the programme will be held virtually as it was done in 2020 and 2021. Website: http://eso.org/summerresearch/ ESO - SummerResearch2021 ESO is the European Organisation for Astronomical Research in the Southern Hemisphere. It operates the La Silla Paranal Observatory in Chile and has its headquarters in Garching, near Munich, Germany. |
Poster: http://eso.org/sci/meetings/2022/SummerResearch2022/SummerProgramme2022-poster.pdf. Enquiries: summerresearch@eso.org
12. 'Easy' Teaser.
To what am I referring? – "Father confused with eternal city".
13. DIFFICULT TEASER Answered at last!
John Hall was first with the correct answer, on 7 December at 23.45 – well done John!
Second correct answer came from Gary Montgomery at 18.30 on December 9.
Q. "What goes ZZUB?" – the answer to that, per the joke, is "a BEE going backwards".
BEE backwards is EEB, the initials of famous American astronomer EE Barnard. He was always known just by his initials, like JK Rowling, TS Elliot, JRR Tolkien etc, and sometimes just as EEB, like FDR. He worked at Lick Observatory, and then moved to a Professorship at U of Chicago where he used the great 40" refractor at Yerkes Observatory. He's best known for his astrophotography, the discovery of Amalthea and Barnard's Star (the one with the highest known proper motion), and Barnard's Loop. You can Google for more info.
THANKS to everyone else who entered, often multiple times, with imaginative guesses
14. NEW DIFFICULT TEASER
What links - A famous painter, peace, a pleasing sound, fate, and an explorer?
(It's not as difficult as the last one – I'm getting soft again….)
.
Please send all answers to me at my aol address terrymosel@aol.com
15. Davagh Dark Sky Park and Observatory is open, with pre-booking, and some restrictions.
See https://www.midulstercouncil.org/visitor/things-to-do/star-gazing/davagh-dark-sky-observatory , and https://www.facebook.com/omdarksky/ I'll post any updates here. Or phone 03000 132 132 for changing Covid-19 advice.
16. PAYMENT OF IAA ANNUAL SUBSCRIPTION: This is your last chance – if you haven't paid by 12 December, your membership will lapse, and you won't get the next issue of Stardust! Subscriptions were due on September 1. We're glad to be able to keep the amount unchanged for yet another year: £20 for individual membership, £25 for family membership (only one copy of STARDUST per family).
Anyone wishing to pay by bank transfer should contact the Treasurer, Pat O'Neill (pb.oneill@ntlworld.com, or treasurer@irishastro.org) for our bank details.
(See final item below)
17. 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
Evidence emerges for dark-matter free galaxies -- ScienceDaily
This faraway galaxy may be completely devoid of dark matter | Live Science
Astronomers Spot Two Dust Bunnies Hiding in the Early Universe - Scientific American
A young, sun-like star may hold warnings for life on Earth -- ScienceDaily
Researchers capture the fastest optical flash emitted from a newborn supernova -- ScienceDaily
Black hole warning: NASA spots Milky Way's supermassive region of spacetime 'leaking' (msn.com)
Astronomers Capture a Doomed Galaxy Plunging Into a Galactic Furnace (scitechdaily.com)
Black hole jet boasts double helix structure molded by powerful magnetic fields (msn.com)
Giant Stars and the Ultimate Fate of the Sun - Universe Today
COSMOLOGY:
Record-breaking simulations of large-scale structure formation in the Universe -- ScienceDaily
Hmmmm Gravitational waves could be key to answering why more matter was left over after Big Bang -- ScienceDaily. A lot of ifs and maybes….
Could Gravity's Quantum Origins Explain Dark Energy? - Scientific American
Maybe "Boson Clouds" Could Explain Dark Matter - Universe Today
EARTH & MOON
NASA's asteroid-impact monitoring system gets accuracy upgrade (newatlas.com)
New source of potent greenhouse gas emissions identified in permafrost (newatlas.com)
A young, sun-like star may hold warnings for life on Earth -- ScienceDaily
Asteroid Apophis' 2029 Flyby Will Provide a Bonanza of Asteroid Science - Universe Today
EXOPLANETS
Record-breaking alien planet spotted circling massive, superhot star duo (photo) (msn.com) Note: 'b Centauri' is totally different from Beta Centauri. The naming convention is that the brightest star in a constellation (usually) is alpha, followed by Beta for the 2nd brightest, Gamma for the 3rd brightest, etc through to Omega for the 24th brightest. After that fainter ones are given English letters (a, b, c through to z) then numbers – but it's complicated. This star is at RA 14h 42m, Dec -37 48', and is mag 4.0, so it would be visible to the naked eye.
ESO telescope images planet around most massive star pair to date -- ScienceDaily
GENERAL
Hunt for Alien Life Tops Next-Gen Wish List for U.S. Astronomy - Scientific American
IMAGES
Awe-inspiring auroras dazzle in annual Northern Lights photo compilation (newatlas.com)
The TSE from Antarctica https://apod.nasa.gov/apod/ap211209.html
SETI
A New Way to Detect Alien Megastructures - Universe Today What exactly would we need 3.8 x10 to power 26 Joules per second for????
SOLAR SYSTEM
NASA looks into unusual Mars helicopter communications hiccup during flight (msn.com)
NASA's asteroid-impact monitoring system gets accuracy upgrade (newatlas.com)
The 7 Strangest Asteroids: Weird Space Rocks in Our Solar System | Live Science
Scientists Amazed by What They Saw After NASA's Voyager 2 Entered Deep Space | Gadgetheory
If There are Water Plumes on Europa, Here's how Europa Clipper Will Study Them - Universe Today
Asteroid Apophis' 2029 Flyby Will Provide a Bonanza of Asteroid Science - Universe Today
Some of the biggest telescopes in the world will, hopefully, be operational by then - but I doubt if any of the biggest ones will be able to track an object going that fast! However, with their enormous light grasp they'll be able to image it in such short exposures that its apparent motion won't matter.
SPACE
Japanese billionaire Yusaku Maezawa, two crewmates arrive at International Space Station | Space
Rocket Lab Shows off its new Reusable Neutron Rocket, due for Launch in 2024 - Universe Today
Space travel's surprising impact upon humanity (mashable.com)
SUN
Giant Stars and the Ultimate Fate of the Sun - Universe Today
Telescopes, Instruments, Techniques.
Nasa brings Hubble Space Telescope back to life after months of glitches (msn.com)
Hunt for Alien Life Tops Next-Gen Wish List for U.S. Astronomy - Scientific American
SpaceX Falcon 9 rocket launches NASA's new IXPE X-ray space telescope | Space
Optical cavities could be key to next generation interferometers -- ScienceDaily
18. JOINING the IRISH ASTRONOMICAL ASSOCIATION. This link downloads a Word document to join the IAA. http://documents.irishastro.org.uk/iaamembership.doc
If you are a UK taxpayer, please tick 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
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