Hi all,
1. PERSEID METEORS
The shower peaks at 19h UT on August 12, although the shower is active for much longer than that, and some members can be seen right up to about August 20, although at rapidly diminishing rates.
Unfortunately maximum coincides with Full Moon, which will seriously hamper viewing!
The ZHR is normally around 80, but with the moonlight, we'll be lucky to see about 25 per hour.
The best trick is to look at an area of the sky with the Moon behind you, and preferably behind a building, wall or trees etc. You don't need to look at the radiant, which is near the famous 'Double Cluster' near the border with Andromeda. In fact looking about 40-50 degrees away from the radiant and about the same amount above the horizon, generally gives the best observed rates.
On the nights after Full Moon, you get an hour or two of moon-free skies, so you could also try your luck then – say from about Aug 14 – 18.
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.
These meteors have been observed for at least 2 millennia, as the Earth passes through dust left in the wake of Comet 109P/Swift–Tuttle.
2. Protecting Dark Skies in Ireland, 15 August
Event by Dark Sky Ireland, Mon, Aug 15, 2022, 7:00 PM - 8:00 PM (your local time), Online
Event link https://us02web.zoom.us/meeting/register/tZctd-CvqzIqHNBewOaCH3_bJYg1vm8GlR2D
3. Saturn at Opposition, 14 August
Saturn reaches opposition and rises in the southeast as the Sun sets in the northwest. This marks the planet's closest approach to Earth this year at a distance of 1.324 billion kilometres. At magnitude +0.3, Saturn is easily visible in eastern Capricorn all night.
Saturn still lies about 15 degrees south of the celestial equator, so northern observers need nights of good seeing to get the best view of the planet and its rings. At opposition, the rings span nearly 44 arc-seconds, with a tilt of about 13 degrees. The disk is about 19 arc-seconds in diameter.
Any telescope will show Titan, the largest and brightest of the planet's moons. The other main moons, in order moving in closer to the planet than Titan, and in order of decreasing magnitude and therefore difficulty to observe, are Rhea, Dione, Tethys, Enceladus and Mimas – the latter requiring probably at least a 30cm instrument, and good seeing. Much further out than Titan lies Iapetus, always much brighter at Western Elongation, and as it's just past that position at the moment, you may be able to catch it with a 15cm telescope or larger for the next few nights, although the nearby bright Moon won't help!
4. Dark Sky Events for Heritage Week - 13th to 20th August
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7. Mayo Dark Sky Festival, 4-6 November. More details later.
8. New Easy Teaser - A Clue.
Time is fundamental to many aspects of astronomy. In that context: What comes before and after this sequence. Seven, Eight, Nine, Ten? And it's obviously NOT just Six, and Eleven!
No answers yet, so here's a clue: Think of it in a different language.
9. New Difficult Teaser
What's next in this sequence? – 15, 2, 1, 6, 7?
Again, no answers yet, so here's a clue: the next is 11, so what's the one after that?
Please send all Teaser answers to me at my aol address terrymosel@aol.com
10. 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:
When Stars eat Their Planets, the Carnage can be Seen Billions of Years Later - Universe Today
Latest James Webb Telescope Images Shed Light on the History of Stars | Watch (msn.com)
Dark matter from billions of years ago finally detected by scientists (msn.com)
Scientists find the secret to birth of earliest black holes in the Cosmos (msn.com)
JWST discovers candidates for most distant galaxies yet | Space
Webb telescope peers through dust for unprecedented look at black hole (msn.com)
Astronomers measure strongest magnetic field ever detected (newatlas.com)
A 'heartbeat' signal is coming from a distant galaxy (msn.com)
World's most sensitive dark matter detector joins the hunt for WIMPs (newatlas.com)
COSMOLOGY:
Dark matter from billions of years ago finally detected by scientists (msn.com)
Scientists find the secret to birth of earliest black holes in the Cosmos (msn.com)
EARTH & MOON
Earth's Magnetic Field Almost Completely Collapsed 550 Million Years Ago - Universe Today
Lava Tubes on the Moon Maintain Comfortable Room Temperatures Inside - Universe Today, and
The Moon's One Spot of Perfect Temperature - The Atlantic. The problem is that these all seem to be at relatively low lunar latitudes, whereas the water on the Moon is almost exclusively at the poles, mainly the S. Pole. If only they were beside each other! However, it's possible that there's some water in the horizontal parts of the deeper tubes, which of course we can't see.
Earth records its shortest day ever (msn.com) and
Earth is suddenly spinning faster than usual, but why? (msn.com) This is very odd, as the opposite should be happening, due to the melting of polar ice! Something must be happening at the levels of the core and the lower mantle.
Newly discovered chemical reactions could explain the origin of life (newatlas.com)
With lunar orbiter, South Korea will join a revived race to explore the Moon | Science | AAAS
10 Earth impact craters you must see (msn.com)
What a Martian meteorite can teach us about Earth's origins -- ScienceDaily
NLCs increase due to rocket launches Northern Mid‐Latitude Mesospheric Cloud Frequencies Observed by AIM/CIPS: Interannual Variability Driven by Space Traffic - Stevens - 2022 - Earth and Space Science - Wiley Online Library
EXOLIFE
Scientists say we should look for city lights on other planets in the hunt for alien life (msn.com) One would hope that if they're intelligent, they have tried to minimise light pollution.
EXOPLANETS
Disk of gas observed around what might be youngest exoplanet yet discovered (msn.com)
Undead planets: The unusual conditions of the first exoplanet detection -- ScienceDaily
IMAGES
See James Webb Space Telescope's reach into the universe (video) | Space
Hubble Space Telescope captures a dazzling star cluster | Space
NASA's James Webb telescope releases spectacular image of Cartwheel Galaxy (msn.com)
Amazing views of the Universe captured by the James Webb Space Telescope (msn.com)
The James Webb Space Telescope's first images are here, and they're spectacular | Live Science and
NASA Reveals Webb Telescope's first images of unseen universe -- ScienceDaily and
Nasa unveils stunning new images [Video] (aol.co.uk)
Correction needed: the speed of light is NOT 186 miles per second - it's 186,000 miles per second!
James Webb vs Hubble: Side-by-side comparisons highlight visual gains (newatlas.com)
SOLAR SYSTEM
Powerful cosmic explosions left abundant stardust in the solar system | Space
Planet 9 is Running out of Places to Hide - Universe Today
Jupiter's Giant Moons Prevent it From Having Rings Like Saturn - Universe Today
The inner solar system spins much more slowly than it should | Space
Journey to the mystery planet: why Uranus is the new target for space exploration (msn.com) The main moons of Uranus also orbit in the plane of its equator, i.e. tilted at an angle to the orbit of over 90 degrees. How did that happen? An impact on the planet would not move the moons. So they must be the remains of the collision, rather than captured asteroids or KBOs.
Far beyond Pluto: What's next for NASA's New Horizons probe? (msn.com)
Europe ending cooperation with Russia on ExoMars rover | Space
SCIENCE (not) FICTION: A crucial step towards interplanetary colonisation | Watch (msn.com)
Perseverance Mars rover collects its 10th rock sample | Space
What a Martian meteorite can teach us about Earth's origins -- ScienceDaily
SPACE
Shenzhou 14 crew starts testing new space station module (video) | Space
NASA unleashes fury at Xi as China's rocket comes CRASHING back down to Earth (msn.com)
Move over Cape Canaveral, Cornwall is about to become epicentre of UK's world class space industry - and this is a race Britain MUST win (msn.com) I don't think that Cape Canaveral has too much to worry about...
Remains of China rocket booster fall to Earth (msn.com)
With lunar orbiter, South Korea will join a revived race to explore the Moon | Science | AAAS
Buzz Aldrin jacket becomes most valuable US space-artefact (aol.co.uk)
A huge rocket is plummeting to Earth, scientists can't tell where it'll land | Watch (msn.com)
NASA to launch 2 more choppers to Mars to help return rocks (msn.com)
China launch module into space to complete orbiting outpost | Watch (msn.com)
NASA considers sending scientists to the space station: report | Space
Italian astronaut and Russian cosmonaut team up for spacewalk (msn.com)
Europe ending cooperation with Russia on ExoMars rover | Space
Europe's Vega C rocket launches 7 satellites on debut mission | Space
Space rocket junk could have deadly consequences unless governments act -- ScienceDaily
Elon Musk's massive Mars rocket suffers an explosive setback (newatlas.com)
TELESCOPES, INSTRUMENTS, TECHNIQUES.
Europe's major X-ray space telescope may get scaled back | Space
A Mission to Reach the Solar Gravitational Lens in 30 Years - Universe Today And the telescope/satellite would have to have enough power, and a big enough directional antenna, to send image data back at a meaningful rate.
Nancy Grace Roman Will be Launching on a Falcon Heavy Rocket - Universe Today
Gamma-ray Bursts can Help Astronomers Measure Vast Distances Across the Universe - Universe Today
Far beyond Pluto: What's next for NASA's New Horizons probe? (msn.com)
World's most sensitive dark matter detector delivers first results | Space
World's most sensitive dark matter detector joins the hunt for WIMPs (newatlas.com)
Researchers remeasure gravitational constant -- ScienceDaily For the record, the latest value is 6.6743 x 10 to -11 m3 kg-1 s-2. So that's given to 4 decimal places. OTOH, the value for the Gaussian gravitational constant given in the 2020 BAAH is 0.01720209895, which seems reasonably precise to me! It's used in Solar System orbital mechanics, relating period to semi-major axis and the body's mass.
11. 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
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