1. IAA Double Public Lecture, Wednesday December 18, 7.30 p.m. (1.) "The Cosmic Compass" by IAA President, Brian Beesley.
Summary: Part 1 is a (non technical) description of how astronomy has been used to find where you are and what direction you're moving in from ancient times up to the Apollo missions. Part 2 is a description of the basics of satellite navigation together with how this technology developed from WWII radio navigation and blind bombing aids.
(2) "Deep Sky Astrophotography with a Small Telescope." by IAA C/M Adam Jeffers
Summary: This talk will outline the equipment, stages and software involved in capturing and processing an image of a deep sky object from your back garden.
Biography: I have been enjoying astrophotography for over ten years, but over the past two and half years I have become increasingly involved in the hobby.
I am a council member of the Irish Astronomical Association, and a member of the Nemetode Meteor Network - collecting meteor data over the SW of Ireland.
I am currently involved in a minor consulting capacity for Mid-Ulster Council, assisting in the setup and selection of the telescope and imaging equipment for the new Davagh Dark Skies Project outside Cookstown. Additionally I am part of a team collecting All Sky Camera data, facilitating Davagh's application to the IDA for dark sky status.
Details; 7.30 p.m., Bell Lecture Theatre, Physics Building , QUB. Admission free, including light refreshments. See www.irishastro.org.
2 GEMINIDS The Geminids are the year's richest meteor shower, with a ZHR of 120, with peak activity on the nights of Dec 13/14 and 14/15. However the Moon will be just past Full, so it will spoil the view considerably! But Geminids are generally slow meteors, with some bright fireballs, so it's worth having a look even in the Moonlight, by hiding the Moon behind something like a building or tree, and looking in the opposite direction.
Activity begins about 7 Dec, and builds up to the date of maximum, so it's worth looking on the few nights before maximum as well. The radiant is near Castor.
The Geminids are unusual in that the parent body, Phaethon, is classed as an asteroid, not a comet!
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.
3. Ursids Meteor shower, 20-21 December. A minor shower, peaking around 20-21 December, but at least the Moon won't interfere as much as it does with the Geminids
4. ISS The International Space Station will commence a series of morning passes on 20 December. Look out for it on Xmas morning, but don't confuse it with another aerial object expected to be around at that time…. Full details for your location, and lots of other astronomy information, on the excellent free site www.heavens-above.com
5. Starlink satellite trains Some of the Starlink satellites launched in a long 'string' are visible to the naked eye in the morning skies. There are scores of them (far too many!), so check site www.heavens-above.com for details. They are going to be a real problem for astronomers.
6. Winter Solstice. The Sun will reach the most southerly point on the ecliptic in its apparent annual journey round the sky on Dec 22 at 04.19. It will then have an apparent declination of -23º 26' 15.2". But an almanac will list its declination as -23º 26' 9.6". The difference is due to the fact that the almanac gives the geocentric position, whereas we are at about 54º North latitude.
7. Alan Fitzsimmons says ESA wants our help re HERA Mission. .
https://newatlas.com/space/esa-enlists-amateur-astronomers-plan-hera-asteroid-mission/?utm_source=New+Atlas+Subscribers&utm_campaign=46ad5d7014-EMAIL_CAMPAIGN_2019_11_27_06_22&utm_medium=email&utm_term=0_65b67362bd-46ad5d7014-92786061 Note that our young IAA member Hayden Geraghty, is an 'Ambassador for HERA'!
8. Mission Santa, Christmas experience, AOP, every Saturday 30 Nov – 22 Dec. For kids, of course. Booking at www.armagh.space
9. Telescope workshop, stargazing and Dome Show, IAA at AOP, 30 December
Are you purchasing a telescope for Christmas? We can give help and advice with scopes alongside our friends from the Irish Astronomical Association on Monday 30 Dec. Doors open 6.30pm, stargazing and telescope clinic from 7pm with dome show "CapCom Go" screening at 8pm.
10. IAA New Year Party, January 4. we start off with a buffet meal in McBride's, The Square, Comber, at 5.30, followed by a private screening of classic SciFi Film: Destination Moon at the Tudor Private Cinema at 7.00, where there will be some light liquid refreshments in the form of mulled wine, light-alcohol punch, and soft drinks. And maybe a mince pie or two. The film will be followed by a quiz, with a selection of prizes
11. Galway Astronomy Festival
The Galway Astronomy Festival takes place on Saturday January 25th 2020.
The festival will take place in the Harbour Hotel, overlooking Galway Bay
12. Vesta occults naked eye star, 11 February. More details of this rare event, visible from the N of the island, will be in the January edition of STARDUST, and in later bulletins.
13. 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
Gravitational waves make their own waves. https://www.livescience.com/universe-remembers-gravitational-waves.html?utm_source=Selligent&utm_medium=email&utm_campaign=11071&utm_content=20191207_LS_Essentials_Newsletter+-+adhoc_2+&utm_term=3473357&m_i=bj_YaDCX468JM7qfv4KZ6_HgNjUGVPdSGUzn7WSWJsfmy2pXzRyEEc5YVaDsqgEIRSmGOWty6QmpHvJd_bPrlxm02uVzD5FZbm
New type of neutron star flashes oddly at Earth https://www.livescience.com/weird-neutron-star.html?utm_source=Selligent&utm_medium=email&utm_campaign=11247&utm_content=20191211_LS_Essentials_Newsletter+-+adhoc+&utm_term=3473357&m_i=RD%2BcPk1oBKElkZmHqH5Y5Cwn9LBPrk0W5h795%2BVeT4idP3q8_KbfTx6CDNDgrfezQmlrMSzo1_71YRi_dWxWMMQw3HvaJbDaRL
ALMA spots most distant dusty galaxy https://www.sciencedaily.com/releases/2019/12/191211121901.htm
COSMOLOGY
Dark matter fights back in galaxy - https://www.msn.com/en-ie/news/techandscience/dark-matter-strikes-back-in-galactic-mystery/ar-AAK711u?ocid=spartandhp
EARTH & MOON
https://www.sciencemag.org/news/2019/12/space-budget-boost-puts-europe-lead-monitor-carbon-space
Archaeon micro-organism prefers meteorites https://www.sciencedaily.com/releases/2019/12/191204144903.htm
Greenland ice disappearing 7 times faster now https://www.sciencedaily.com/releases/2019/12/191210111701.htm
Earth building material came from Red Giants https://www.sciencedaily.com/releases/2019/12/191210111643.htm
This could be very serious. https://www.nationalgeographic.com/science/2019/12/why-ocean-current-critical-to-world-weather-losing-steam-arctic/?cmpid=org=ngp::mc=crm-email::src=ngp::cmp=editorial::add=Science_20191211-&rid=B44D5BDD89C3D2302973C899D2E91C40
Satellite data reveals glacier retreat. https://www.sciencedaily.com/releases/2019/12/191210111713.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Ftop_news%2Ftop_science+%28ScienceDaily%3A+Top+Science+News%29 Yes, Greta is right, you know, as just recognised by Time Magazine.
It's even more complex than that. The main factors are the phase, obviously, and the Moon's varying distance from both Earth and Sun. But you also need to allow for libration, which causes the Moon to slightly alter the side that's facing Earth.
This occurs in both an E-W and a N-S direction, by up to over 10 degrees combined effect. Since the Moon's Southern hemisphere is brighter than the Northern hemisphere, and the East hemisphere is brighter than the West, this can produce a considerable difference, particularly when combined with the phase. For example, all other things being equal, 1st Quarter will be brighter than 3rd Quarter, but if the libration brings more of the E side of the Moon towards us, the effect will be even greater. And if there's Southerly libration as well, even more so! And vice versa for both librations.
EXOPLANETS
Composition of gas giants does not depend on host star https://www.sciencedaily.com/releases/2019/12/191203114527.htm
Giant planet orbits white dwarf star https://www.sciencedaily.com/releases/2019/12/191204145847.htm and
https://www.dailymail.co.uk/sciencetech/article-7755699/Giant-planet-orbiting-white-dwarf-provides-evidence-planet-survive-death-star.html Sorry folks, but that is NOT the VLT - it's not even remotely like it!
How planets form from dust https://www.sciencedaily.com/releases/2019/12/191209112143.htm
Planet-mass objects discovered in other galaxies https://www.sciencedaily.com/releases/2019/12/191212095904.htm
Water is common, but in low amounts, in exoplanets https://www.sciencedaily.com/releases/2019/12/191211082656.htm
IMAGES
Movie of Martian Moon Phobos https://newatlas.com/space/european-spacecraft-martian-moon-phobos/?utm_source=New+Atlas+Subscribers&utm_campaign=a068c39066-EMAIL_CAMPAIGN_2019_12_13_09_24&utm_medium=email&utm_term=0_65b67362bd-a068c39066-92786061
SOLAR SYSTEM
Titan offers useful information re Earth https://www.sciencedaily.com/releases/2019/12/191203114522.htm
TESS accidentally catches comet outburst https://newatlas.com/space/tess-satellite-comet-outburst-wirtanen/?utm_source=New+Atlas+Subscribers&utm_campaign=0510698b90-EMAIL_CAMPAIGN_2019_12_04_07_22&utm_medium=email&utm_term=0_65b67362bd-0510698b90-92786061
New Horizons may reach termination shock sooner than expected https://newatlas.com/space/new-horizons-reach-solar-system-termination-shock-sooner/?utm_source=New+Atlas+Subscribers&utm_campaign=0510698b90-EMAIL_CAMPAIGN_2019_12_04_07_22&utm_medium=email&utm_term=0_65b67362bd-0510698b90-92786061
Very rare mineral in Siberian meteorite https://affluenttimes.com/science/space/scientists-unearthed-meteorite-siberia-inside-made-extraterrestrial-discovery/?utm_source=Taboola&utm_medium=CPC&utm_content=msn-edgedefaulthomepage-uk_1053576&utm_campaign=73866_Affluent-Times_Scientists-Unearthed-A-Meteori_GB_DESKTOP_DZ&utm_term=3367042&l=a
Ejections from Asteroid Bennu explained. https://www.sciencedaily.com/releases/2019/12/191205145112.htm I certainly wouldn't describe something 10cm across as a "particle". That's an 'object', or a 'piece' or a pebble, depending on the composition.
TESS's detailed capture of comet outburst https://www.sciencedaily.com/releases/2019/12/191203164336.htm
Bennu and the jets! https://www.dailymail.co.uk/sciencetech/article-7760685/NASA-captures-incredible-close-shot-plumes-dust-leaving-asteroid.html
Geminids debris trail imaged by Parker Solar Probe https://www.msn.com/en-gb/news/techandscience/geminid-meteor-showers-parent-debris-trail-spotted-for-1st-time-photo/ar-AAK3qUc?ocid=spartandhp
Proton aurora is the commonest type on Mars https://www.sciencedaily.com/releases/2019/12/191212105857.htm
Asteroid Bennu's sample site is chosen https://newatlas.com/space/nasa-selects-sample-site-osiris-rex/?utm_source=New+Atlas+Subscribers&utm_campaign=a068c39066-EMAIL_CAMPAIGN_2019_12_13_09_24&utm_medium=email&utm_term=0_65b67362bd-a068c39066-92786061
SPACE
Next generation Search & Recue beacons for Artemis crew https://newatlas.com/space/nasa-introduce-second-generation-gps-search-rescue-beacon-artemis/?utm_source=New+Atlas+Subscribers&utm_campaign=0510698b90-EMAIL_CAMPAIGN_2019_12_04_07_22&utm_medium=email&utm_term=0_65b67362bd-0510698b90-92786061
https://www.sciencemag.org/news/2019/12/space-budget-boost-puts-europe-lead-monitor-carbon-space
Asgardia news https://mail.aol.com/webmail-std/en-gb/DisplayMessage?ws_popup=true&ws_suite=true
There are a few pros and many cons. The acceleration is very very slow, even with a very lightweight spacecraft, and it decreases the further you get from the Sun. But it does continue.
In our SS, it's only useful for flybys, as it doesn't allow the craft to slow down or go into orbit.
For travel to another star system, it would be faster than our present rockets, but still incredibly slow. It would very slowly accelerate to the point where the radiation from the target star was equal to that from our Sun; then it would use that radiation to very slowly decelerate.
Imagine a trip to the nearest star system, Alpha Centauri, 4.35 light years, (413,000,000,000,000km) away. The spacecraft would very very slowly move away from the Sun - remember that even at the mean distance of Pluto, the Sun is only 1/1,520 times as bright as it is on Earth. And Pluto is 70,000 times closer to us than Alpha Centauri!.
So from about 1/10 of the way to the target, there's very little further acceleration, just coasting.
Then when it's about 90% of the way to the target, the radiation from Alpha will start to decelerate it, but again, very very slowly.
Then when it's about 150 million km from Alpha, it will have slowed to the speed it had when it left Earth orbit a few centuries earlier!
And all this assumes an incredibly lightweight spacecraft; begging the question just how much instrumentation it could carry, and how it could send data back to Earth.
Another danger is that the huge sail (at least 1 km square) would strike a small space rock while going through the asteroid belt, sending it tumbling out of control. A piece the size of just a pea could be enough to do that. There are probably billions of those in the asteroid belt! And it would spend months, if not years, going through the asteroid belt, increasing the risk of collision. It would need some sort of onboard attitude control jets and fuel to try to correct for that, which would add more weight to the craft, making it even slower.
If we did send one, a likely scenario is that after it was on its way we would develop a much faster more powerful rocket, perhaps nuclear-powered, with a hefty payload of instruments and transmitters, which would overtake the light-sail long before it got there, making it redundant.
SUN
Detecting solar flares and other events in real time https://www.sciencedaily.com/releases/2019/12/191203133847.htm
Parker Solar Probe's first close flyby results https://newatlas.com/space/nasa-first-results-parker-solar-probe-mission/?utm_source=New+Atlas+Subscribers&utm_campaign=17c204fe94-EMAIL_CAMPAIGN_2019_12_06_09_13&utm_medium=email&utm_term=0_65b67362bd-17c204fe94-92786061
PSP traces solar wind to its source in coronal holes https://www.sciencedaily.com/releases/2019/12/191204145828.htm
PSP's set of results from first close pass to Sun https://www.sciencedaily.com/releases/2019/12/191204144903.htm and
https://www.sciencedaily.com/releases/2019/12/191204152831.htm
TELESCOPES, INSTRUMENTS, TECHNIQUES
New guide for discovering life on exoplanets https://www.sciencedaily.com/releases/2019/12/191204152823.htm
14. 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 www.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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