July 2021 News and research items
Hi everyone
The highlight this month was attending the RASNZ conference here in Wellington. It was a convenient location too as it meant no travelling or accommodation. It was great to see a number of old friends and meet some new ones. There was a great range of talks and photos up on social media too.
This month there is a look at photosynthesis on Earth like planets, an interesting look around the galaxy at how aliens could colonise it. Mercury has a look in too, why is it so dense with a large core? A new study suggested the magnetic field of the sun might have had a influence on the forming planets with the closer ones gaining more iron.
The BBC has a really good article on light pollution that is a great read. There is a look at Tectonic forces on Venus and thanks to Lawrence on the Van Gough article.
So planet of interesting things to read this month
Cheers Edwin
Research papers
Efficiency of the oxygenic photosynthesis on Earth-like planets in the habitable zone
https://academic.oup.com/mnras/article/505/3/3329/6278213
Implications of a search for intergalactic civilizations on prior estimates of human survival and travel speed
https://arxiv.org/abs/2106.13348
The Temporal Onset of Habitability For Earth-Like Planets
https://arxiv.org/abs/2106.14852
Terrestrial planet compositions controlled by accretion disk magnetic field
https://progearthplanetsci.springeropen.com/articles/10.1186/s40645-021-00429-4
Why Does Mercury Have Such A Big Iron Core? Magnetism!
http://spaceref.com/mercury/why-does-mercury-have-such-a-big-iron-core-magnetism.html
Present and Future Stars that can see Earth as a Transiting Exoplanet
https://arxiv.org/abs/2107.07936
Extending the Planet Simulator for Exoplanets
https://arxiv.org/abs/2107.07685
Planetary magnetosphere evolution around post-main-sequence stars
https://arxiv.org/abs/2106.10293
Limits of Detecting Extraterrestrial Civilizations
https://arxiv.org/abs/2107.09794
Dinosaur biodiversity declined well before the asteroid impact, influenced by ecological and environmental pressures
https://www.nature.com/articles/s41467-021-23754-0
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Interesting News items
Some great work here
https://www.stuff.co.nz/travel/destinations/nz/wellington/125620423/new-zealands-largest-dark-sky-reserve-one-step-closer-in-wairarapa
A World of Ice, With Potential for Life - NASA's Europa Clipper
http://astrobiology.com/2021/06/europa-a-world-of-ice-with-potential-for-life---nasas-europa-clipper.html
Special Issue released on Volcanism in Zealandia and the SW Pacific
https://www.royalsociety.org.nz/news/special-issue-released-on-volcanism-in-zealandia-and-the-sw-pacific-part-2-north-island/
Icequakes Likely Rumble Along Geyser-spitting Fractures In Saturn's Icy Moon Enceladus
http://astrobiology.com/2021/07/icequakes-likely-rumble-along-geyser-spitting-fractures-in-saturns-icy-moon-enceladus.html
Goldilocks Planets With A Tilt May Develop More Complex Life
http://astrobiology.com/2021/07/goldilocks-planets-with-a-tilt-may-develop-more-complex-life.html
A good look at the impacts of light pollution here
https://www.bbc.com/future/article/20210719-why-light-pollution-is-harming-our-wildlife
The Fascinating Story Behind the Painting That Led to Van Gogh’s ‘Starry Night’
https://mymodernmet.com/starry-night-over-the-rhone
10 the most spectacular celestial events to watch in 2021-2040
http://www.mkrgeo-blog.com/10-the-most-spectacular-celestial-events-to-watch-in-2021-2040
An interesting update on Megaconstellations
https://www.forbes.com/sites/startswithabang/2021/07/22/how-to-save-the-night-sky-from-satellite-megaconstellations
An interesting look at tectonics at Venus
https://astronomy.com/news/2021/07/turns-out-venus-almost-has-tectonic-plates
Astronomy_News_20_07_2021
This months research Papers 20_06_2021
RASNZ_20_07_2021
Further links and discussion can be found at the groups/links below
Astronomy in New Zealand - Facebook
https://www.facebook.com/groups/5889909863/
Astronomy in New Zealand - Groups.io
https://groups.io/g/AstronomyNZ
Google Group
https://groups.google.com/g/nzastrochat
Astronomy in Wellington
https://www.facebook.com/groups/11451597655/
Blogger Posts
http://laintal.blogspot.com/
Reddit
https://www.reddit.com/user/Edwin_Rod_NZ
Quaroa
https://www.quora.com/q/astronomyinnewzealand
Twitter
https://twitter.com/Laintal
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Research papers
Efficiency of the oxygenic photosynthesis on Earth-like planets in the habitable zone
https://academic.oup.com/mnras/article/505/3/3329/6278213
Implications of a search for intergalactic civilizations on prior estimates of human survival and travel speed
https://arxiv.org/abs/2106.13348
The Temporal Onset of Habitability For Earth-Like Planets
https://arxiv.org/abs/2106.14852
Terrestrial planet compositions controlled by accretion disk magnetic field
https://progearthplanetsci.springeropen.com/articles/10.1186/s40645-021-00429-4
Why Does Mercury Have Such A Big Iron Core? Magnetism!
http://spaceref.com/mercury/why-does-mercury-have-such-a-big-iron-core-magnetism.html
Present and Future Stars that can see Earth as a Transiting Exoplanet
https://arxiv.org/abs/2107.07936
Extending the Planet Simulator for Exoplanets
https://arxiv.org/abs/2107.07685
Planetary magnetosphere evolution around post-main-sequence stars
https://arxiv.org/abs/2106.10293
Limits of Detecting Extraterrestrial Civilizations
https://arxiv.org/abs/2107.09794
Dinosaur biodiversity declined well before the asteroid impact, influenced by ecological and environmental pressures
https://www.nature.com/articles/s41467-021-23754-0
----------------------------------------------------------------------
Interesting News items
Some great work here
https://www.stuff.co.nz/travel/destinations/nz/wellington/125620423/new-zealands-largest-dark-sky-reserve-one-step-closer-in-wairarapa
A World of Ice, With Potential for Life - NASA's Europa Clipper
http://astrobiology.com/2021/06/europa-a-world-of-ice-with-potential-for-life---nasas-europa-clipper.html
Special Issue released on Volcanism in Zealandia and the SW Pacific
https://www.royalsociety.org.nz/news/special-issue-released-on-volcanism-in-zealandia-and-the-sw-pacific-part-2-north-island/
Icequakes Likely Rumble Along Geyser-spitting Fractures In Saturn's Icy Moon Enceladus
http://astrobiology.com/2021/07/icequakes-likely-rumble-along-geyser-spitting-fractures-in-saturns-icy-moon-enceladus.html
Goldilocks Planets With A Tilt May Develop More Complex Life
http://astrobiology.com/2021/07/goldilocks-planets-with-a-tilt-may-develop-more-complex-life.html
A good look at the impacts of light pollution here
https://www.bbc.com/future/article/20210719-why-light-pollution-is-harming-our-wildlife
The Fascinating Story Behind the Painting That Led to Van Gogh’s ‘Starry Night’
https://mymodernmet.com/starry-night-over-the-rhone
10 the most spectacular celestial events to watch in 2021-2040
http://www.mkrgeo-blog.com/10-the-most-spectacular-celestial-events-to-watch-in-2021-2040
An interesting update on Megaconstellations
https://www.forbes.com/sites/startswithabang/2021/07/22/how-to-save-the-night-sky-from-satellite-megaconstellations
An interesting look at tectonics at Venus
https://astronomy.com/news/2021/07/turns-out-venus-almost-has-tectonic-plates
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Updates from Andrew B,
Sunday 27th June 2021.
Zhurong Rover.
View of lander section in the distance. Also Parachute and backshell in the distance but quite a bit closer as Zhurong drives south.
Note how much smoother and less rocky than from much further north in Utopia Planitia as seen by the historic NASA Viking 2 lander in 1977.
There is also a new 360 degree panorama in the late martian afternoon. Rear Hazard Camera view added too.
China National Space Administration / CNSA Zhurong Rover has driven down the ramp off the lander onto the plains of Utopia Planitia. Zhurong was a Fire God in ancient China.
Southwest Utopia Planitia. Amenthes Quadrangle.
Position confirmed as 109.9 East, 25.1 North.
Utopia Planitia (No Where Plain) is a huge lava flooded impact basin, one of the largest if not the largest known impact crater in the solar system. It is about 3,300 KM / 2,051 miles wide and parts of it are within the Casius, Amenthes, and Cebrenia quadrangles in the northern hemisphere of Mars.
Very different to the views from Viking 2 which is 1,721 KM / 1,069 miles to the NE, also in Utopia Planitia, further north in Cebrenia Quadrangle. Much less rockier here than at Viking 2.
Zhurong drive seen by drop camera.
https://www.youtube.com/watch?v=yWl4Om-aOro
Zhurong supersonic parachute deployment, backshell release and downward view.
https://www.youtube.com/watch?v=qmZH557xOAM
Zhurong sounds whilst driving off landing platform.
https://www.youtube.com/watch?v=5Xa97M5nsWU
Slides & Text: Andrew R Brown.
CNSA / China National Space Administration.
Friday 23rd July 2021.
Mars InSight / Interior Exploration using Seismic Investigations, Geodesy and Heat Transport Lander.
Science results have been released concerning the Mars InSight / Interior Exploration using Seismic Investigations, Geodesy and Heat Transport Lander which successfully landed on the lava plains within south west Elysium Planitia, Elysium Quadrangle on: Monday 26th November 2018.
Interesting results they are too.
The SEIS / Seismometer and the RISE / Rotation and Interior Structure Experiment have determined the following about Mars.
1). Mars has a thinner expected crust, could be locally rather than globally. The crust appears to have at leat two sub layers with a total depth of about 20 KM / 12 miles. If the third sublayer is conformed, the depth could be 37 KM / 23 miles.
2). Mars appears to have a mantle 1,540 KM / 957 miles deep, and appears to be fairly uniform in composition and is single layered.
3). Mars also appears to have a molten iron core, also to be an alloy with lighter elements. The core is 3,660 KM / 2,274 miles wide and currently appears to be a single layered core, like the Moon.
4). All Marsquakes detected to date originate from the Cerberos Fossae area some 1,519 KM / 944 miles to the east. These along with all other Marsquakes detected to date originate within the same area, proving that Cerberus Fossae is a geologically active region, with perhaps magma (unerupted molten rock) moving around deep under the martian crust there. Another possiblity is that these fractures could also result from the cooling of the interior of Mars, cracking the crust, much like the Rupes on Mercury.
I have attached some readings and some of my favourite Mars InSight images.
LMST = Local Mars Standard Time in western Elysium Planitia.
45 degree wide view from the Instrument Deployment Camera / IDC of the Mars InSight lander deck with the volcanic plains in the background to the horizon of Elysium Planitia, Elysium Quadrangle.
120 degree wide views from the Instrument Context Camera of the Seismometer thermal & wind shield and lava plains to the south.
Note how the plains of Elysium Planitia here are remarkably similar to those in SW Utopia Planitia some 1,922 KM / 1,194 miles away as seen by the China National Space Administration / CNSA Zhurong Rover.
Power issues have been a huge concern for Mars inSight in recent months as the solar arrays have become increasingly coated in dust and Mars has just passed through Aphelion, the furthest point from the Sun at a distance of about 250.50 million KM / 156.65 million miles from the Sun. Mars at Aphelion occured on: Tuesday 13th July 2021.
The next Mars Perihelion (closest point to the Sun) will occur on: Tuesday 21st June 2022.
Firstly the dust issue has been somewhat alleviated by a very balsy but appearing to be largely successful plan of the scoop to dump small quantities of duricrust on the deck next to the arrays and allowing the winds to pick up particles from the duricrust, blow them across the arrays knocking off dust particles. It is working and the power output from the arrays has increased a little and continuing to do so.
Perhaps the powering down of the science instruments can be postponed or even not at all. The more seismic & RISE data, the better for sure. The cameras too can keep capturing images.
It was hoped that dust devils would at times pass over InSight and they would remove dust from the solar panels. This happened fairly frequently with the Mars Exporation Rovers, MER A Sprit and MER B Opportunity as well as the Phoenix Mars Lander. All three had vastly extended operational missions in part due to this.
However, this has not happened with Mars InSight Lander.
Whilst it is late Spring in the northern hemisphere on Mars now (InSight landed at about 4.5 North, well within the martian tropics between the equator and the Tropic of Aquarius, Mars's northern tropic), the increased distance towards Aphelion is offsetting the higher rising Sun. It will be the Martian Solstice, northern Summer, southern Winter on: Tuesday 25th August 2021.
Text: Andrew R Brown.
IRIS / Incorporated Research Institutions for Seismology. Earth & Mars.
NASA / JPL-Caltech. Mars InSight.
Interior Exploration using Seismic Investigations, Geodesy and Heat Transport.
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RASNZ
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. Royal Astronomical Society of New Zealand
. Email Newsletter Number 247, 20 July 2021
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Affiliated Societies are welcome to reproduce any item in this email
newsletter or on the RASNZ website http://www.rasnz.org.nz/
in their own newsletters provided an acknowledgement of the source is
also included.
Contents
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1. The Centennial Conference
2. RASNZ Centenary Beanie
3. Jeni Adams Receives NZ's Top Physics Award
4. The Solar System in August
5. Dark Skies Retreat - Near Oamaru, Sept. 10-12
6. Beaumont Prize Writing Competition - Closes Sept. 1
7. New Zealand Astrophotography Competition - Closes Sept. 21
8. Comet Bernardinelli-Bernstein, the Giant Comet Beyond Saturn
9. Variable Star News
10. Conference: Dark and Quiet Skies for Science and Society – II
11. IAU Statement on Climate Change
12. NASA Exoplanet Watch Seeks Observers
13. Asteroid Rutherford
14. New Type of Stardust
15. Quote
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1. The Centennial Conference
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The RASNZ Centennial Conference and AGM was enjoyed by the nearly 150 who attended. An expanded group of SWAPA students brought extra energy and enthusiasm while the range of excellent speakers, all from around New Zealand because of border controls, was a tribute to astronomy in our country. The conference marked the first 100 years of our society and with the resurgence of Matariki heralds a new period of appreciation and understanding of the night sky.
I would like to thank the Wellington Astronomical Society and the Local Organising Committee for their extended hard work in preparing for both last year's cancelled face-to-face conference and this year's return to Wellington. Your hospitality and the Wharewaka venue were enjoyed by all.
Steve Butler,
RASNZ President.
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2. RASNZ Centenary Beanie
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To celebrate the RASNZ 100 years, the Wellington Astronomical Society, who are were the hosts for this year's conference, have organised a Centenary beanie! The black beanie has the RASNZ Logo with "100 years" embroidered on it.
ASTRONZ is taking orders for the RASNZ Centenary beanie from the 26th of July. These beanies have been popular with the first order of 50 sold out. After the 26th of July till the end of August, if you would like one or more please contact: ASTRONZ, Web: https://astronz.nz/
Phone: 09 473 0203 These will be produced on a batch process so please allow for a delivery delay.
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3. Jeni Adams Receives NZ's Top Physics Award
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University of Canterbury Professor Jenni Adams was presented with the 2021 Dan Walls Medal, the top award of the New Zealand Institute of Physics (NZIP), at a ceremony in Wellington on July 13. Dr Natalie Plank of NZIP presented the award.
See the Radio NZ news item, with a link to Jesse Mulligan's interview with Jenni Adams, at
https://www.rnz.co.nz/national/programmes/afternoons/audio/2018803933/professor-becomes-first-woman-to-win-dan-walls-medal
Watch for further details on https://nzip.org.nz/
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Jenni has been involved with the Ice Cube neutrino detector at the South Pole since its inception. It has detected many high-energy neutrinos of cosmological origin. The sources of these have not been certainly identified as yet.
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4. The Solar System in August
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Dates and times shown are NZST (UT + 12 hours). Rise and Set times are for Wellington. They will vary by a few minutes elsewhere in NZ. Data is adapted from that shown by GUIDE 9.1.
THE SUN and PLANETS in AUGUST, Rise & Set, Magnitude & Constellation
AUGUST 1 NZST AUGUST 31 NZST
Mag Cons Rise Set Mag Cons Rise Set
SUN -26.7 Cnc 7.26am 5.28pm -26.7 Leo 6.45am 5.57pm
Mercury -2.1 Cnc 7.33am 5.20pm -0.1 Vir 7.37am 7.56pm
Venus -3.9 Leo 9.01am 8.13pm -4.0 Vir 8.17am 9.18pm
Mars 1.8 Leo 8.34am 7.18pm 1.8 Leo 7.20am 6.57pm
Jupiter -2.8 Aqr 6.57pm 8.37am -2.9 Cap 4.39pm 6.30am
Saturn 0.2 Cap 5.18pm 7.43am 0.3 Cap 3.09pm 5.39am
Uranus 5.8 Ari 1.20am 11.34am 5.7 Ari 11.23pm 9.37am
Neptune 7.8 Aqr 8.56pm 9.32am 7.8 Aqr 6.55pm 7.33am
Pluto 14.5 Sgr 3.58pm 7.00am 14.5 Sgr 1.57pm 5.00am
AUGUST 1 NZST AUGUST 31 NZST
TWILIGHTS morning evening morning evening
Civil: start 6.59am, end 5.55pm start 6.20am, end 6.23pm
Nautical: start 6.26am, end 6.29pm start 5.48am, end 6.55pm
Astro: start 5.54am, end 7.01pm start 5.16am, end 7.27pm
AUGUST PHASES OF THE MOON, times NZST & UT
Last quarter: August 1 at 1.16am (July 31,13:16 UT)
New Moon: August 9 at 1.50am (Aug 8, 13:50 UT)
First quarter: August 16 at 3.20am (Aug 15,15:20 UT)
Full Moon: August 23 at 12.02am (Aug 22,12:02 UT)
Last quarter August 30 at 7.13pm (Aug 30 07:13 UT)
THE PLANETS in AUGUST 2021
MERCURY is at superior conjunction at the beginning of August. Following conjunction Mercury becomes an evening object setting after the Sun. On the 19th Mercury passes Mars. At 6.45 pm that evening, with the Sun 9° below the horizon, Mercury at magnitude -0.5 will be 6° above the horizon, only 9 arc-minutes above Mars.
By the end of August Mercury sets 2 hours after the Sun, giving a brief opportunity to see the planet early evening. At 6.50 pm, the end of nautical twilight, the planet will be 11° up.
VENUS moves further up into the evening sky during August, setting over 3 three hours after the Sun by the 31st, making it a brilliant early evening object to the north of west. The evening of August 11 will see the crescent moon some 6° below Venus.
MARS is also an evening object but falls further behind Venus and gets closer to the Sun during August. By the end of the month it sets only 1 hour after the Sun making it a difficult object for observing. The moon, as a very thin crescent only 3% lit, will be 6° to the right of Mars early evening on the 10th.
JUPITER is at opposition on the 22nd of August and in the sky all night. It will be at its brightest in the second half of the month. The planet, moving to the west in a retrograde sense, crosses from Aquarius to Capricornus on the 19th. Early evening on August 22, two days after opposition, the full moon will be 3.5° to the right of Jupiter. They gradually get further apart during the rest of the night.
SATURN is at opposition at the beginning of August, on the 2nd. So, like Jupiter, is visible most of the night. The moon passes Saturn on the 21st. They are closest at the middle of the day so will be separating by the time they rise for New Zealand.
URANUS and NEPTUNE become visible for more of the night during August. While Uranus remains a morning object rising near midnight, Neptune rises early evening especially by the end of the month.
POSSIBLE BINOCULAR ASTEROIDS in AUGUST
AUGUST 1 NZST AUGUST 31 NZST
Mag Cons transit Mag Cons transit
(1) Ceres 8.8 Tau 7.37am 8.8 Tau 6.09am
(2) Pallas 9.5 Psc 3.13am 8.8 Psc 12.59am
(4) Vesta 7.9 Vir 4.11pm 8.0 Vir 3.04pm
(6) Hebe 8.6 Sgr 11.06pm 9.1 Sgr 8.54pm
(12) Victoria 8.8 Aql 12.01am 9.4 Aql 9.48pm
(89) Julia 9.4 Aqr 2.06am 9.0 Aqr 11.36pm
CERES, in Taurus starts August some 10° above the Pleiades. It rises at 2.22 am. By the end of August it will be in the Hyades closing in on Aldebaran. The two are just over 2° on the 31st.
PALLAS rises at 9.30 pm on the 1st and 7.00 on the 31st. So by then is well placed for evening viewing.
VESTA is an early evening object. On the 1st it rises soon after 10 am and sets at 11 pm. By the 31st it sets at 9.20 pm. It will then be 5.5° to the right of Venus. The crescent moon will be 5° to the lower left of Vesta on the 12th. Later that night they will be only 1° apart - well after they set in NZ
HEBE, in Sagittarius, rises at 4.15 pm on the 1st and 1.43 pm on the 31st. On the latter date it sets 4.05 am so is well placed in the evening sky for viewing.
VICTORIA dims from magnitude 8.8 to 9.4 following its opposition in late July. On the 1st it rises at 5.50 pm soon after sunset and more than 2 hours earlier on the 31st. For much of the month it is about 12° from magnitude 0.9 star Altair.
JULIA has a diameter of 159 km. At opposition towards the end of August it is 1.1 AU from the Earth and 2.1 AU from the Sun. These are near its closest possible to the Sun and the Earth, resulting in a relatively bright magnitude 8.9. At opposition Julia rises close to the time of sunset and sets close to the time of sunrise. On the 21st the asteroid is one-third of a degree from Sadel Melik, at magnitude 2.9 the brightest star in Aquarius
-- Brian Loader
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5. Dark Skies Retreat - Near Oamaru, Sept. 10-12
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The Inaugural Dark Skies Retreat, proudly supported by AstroNZ, is to be held of the weekend of September 10th, 11th, & 12th at Camp Iona, in Herbert, approximately 20 minutes drive South of Oamaru.
Speakers include - Victoria Campbell of Ngai Tahu/Matariki Advisory Committee, Amadeo Enriquez-Ballestero and his Fun with Science show, as well as a Dark Skies Forum with a panel of experts on the subject.
Organized by Damien McNamara, IAU Dark Skies Ambassador, this is set to become an annual event on the NZ astronomy calendar. A weekend getaway, to share research, findings, and stories around the impact of artificial light pollution to life on Earth.
Whether you're a passionate advocate, keen astronomer, or simply want a weekend getaway in a relaxing setting, The Dark Skies Retreat is a must for you!
Prices:
Adults $50 one night; $90 both nights.
Students (10-18) $35 one night, $60 both.
Children under 10, free.
Day guests $20 per day.
Campervan, motorhome, caravan or tent sites: $20/night.
Contact Damien for registration forms, or for further information, at solaur.science@gmail.com
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6. Beaumont Prize Writing Competition - Closes Sept. 1
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The Auckland Astronomical Society advises new rules for the Beaumont Prize Writing Competition:
1. The article must be an original work, typed in acceptable language, capable of being included in the Society Journal. The Society will, at its absolute discretion, have the right to refuse to accept any entry that it deems inappropriate.
2. The article must be no longer than 1500 words and no shorter than 500 words.
3. No more than 3 entries per person can be submitted in any year.
4. The subject of the article must be about an astronomy topic or something that would be of interest or useful for people with an interest in amateur astronomy and/or astronomical science.
5. It does not have to be an article previously published in the Society Journal, but by entering it into the competition the author agrees to give the Auckland Astronomical Society (AAS) the right to use
or publish, with attribution, any articles submitted in AAS or RASNZ (Royal Astronomical Society of New Zealand) publications, websites and/or exhibitions to promote astronomy in New Zealand – including, but not limited to AAS and RASNZ journals, the New Zealand Astronomical Yearbook, AAS or RASNZ website and Facebook pages or in any publication, either printed or digital, that the Society deems appropriate. The publication of entry articles will be of charitable nature and not for profit. Any sponsors of the competition may also require to be allowed to use the submitted article in a non-commercial capacity. Copyright outside of those purposes outlined above will remain with the author.
6. The judge or judges for the competition will be appointed by the Society’s Council. The judge’s decision will be final and no correspondence will be entered into. The judge or judges or their immediate family will be ineligible to enter the competition.
7. The Society’s Council will, each year that the competition is conducted, decide what the prize or prizes and the number of such prizes if more than one.
8. The Society’s Council will decide when the competition will be held as well as the opening and closing dates for entries.
9. The competition will be open to all residents of New Zealand.
Closing date is September 1 and the entries can be sent to <journal@astronomy.org.nz> .
The word “Society in the context of these rules means “Auckland Astronomical Society” (AAS)
-- From the Auckland Astronomical Society's Journal, July 2021.
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7. New Zealand Astrophotography Competition - Closes Sept. 21
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The 2021 New Zealand Astrophotography Competition is now open for entries.
This year's competition will be judged by Robert Gendler, Robert is arguably one of the top deep sky astrophotographers in the world, he specializes in images of deep sky objects with very long exposure times. For more information on our judge please take a look at his work on his website at http://www.robgendlerastropics.com/
The competition has three main categories deep sky, nightscape and solar system, last year we introduced a new time-lapse category but this year we have decided to tweak the rules of this new category so make sure you read over the rules and conditions of entry before submitting your entries. See below.
Prizes include a 12 month subscription to Australian Sky & Telescope magazine, a $500 Celestron Australia Voucher, $500 NZD Sky-Watcher Australia Voucher, and a $300 Astronz gift voucher. The Auckland Astronomical Society will also provide a cash prize for each category winner.
The competition cutoff date is the 21st of September and the competition awards will be announced at the annual Burbidge dinner which is the Auckland Astronomical Society's premier annual event, keep an eye out on the society website for details on the forthcoming Burbidge dinner.
Conditions of entry and entry forms can be downloaded from the Auckland Astronomical Society website here at https://www.astronomy.org.nz/announcing-the-2021-new-zealand-astrophotography-competion-for-the-harry-williams-trophy/ "
-- From Jonathan Green, Director of the RASNZ Astrophotography Section, for the Auckland Astronomical Society.
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8. Comet Bernardinelli-Bernstein, the Giant Comet Beyond Saturn
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Astronomers in New Zealand were the first to spot a coma, or zone of gas and dust, spreading around the megacomet C/2014 UN271, also known as Bernardinelli-Bernstein, which may be 1,000 times more massive than a typical comet. It could be the most massive comet ever found in all of recorded history.
The team that monitors images captured by the Las Cumbres Observatory (LCO) is spread around the world, and images from one of LCO's 1-meter telescopes hosted at the South African Astronomical Observatory were available on June 23 at midnight EDT (0400 GMT). That happens to be afternoon in New Zealand. "The other folks were asleep," recalled LCO team member Michele Bannister, of New Zealand's University of Canterbury, in a statement released on July 14.
At first glance, however, she thought the new imagery was a bust, thanks to the ever-present problem of satellites going through the field of view of telescopes. "The first image had the comet obscured by a satellite streak, and my heart sank," she continued. "But then the others were clear enough, and gosh: there it was, definitely a beautiful little fuzzy dot, not at all crisp like its neighbouring stars."
What caught Bannister's attention was a foamy coma emerging at an incredible distance from the sun. When the image was taken, Bernardinelli-Bernstein was about 19 astronomical units (AU) from the sun. (One AU is the average Earth-sun distance — about 150 million km.) That's roughly double the orbital distance of Saturn from the sun. Solar energy at that juncture is a fraction of what we enjoy here on Earth.
That said, the comet has a lot of mass available to heat up. Bernardinelli-Bernstein's huge core (or nucleus) is estimated to be more than 100 km in diameter, which is three times as large as the next-known largest comet nucleus — that of Comet Hale-Bopp, a famous naked-eye comet that passed by Earth in 1998. Unfortunately for eager astronomers, however, Bernardinelli-Bernstein won't get very close to our planet for observations.
Bernardinelli-Bernstein's closest approach to the sun will still be beyond Saturn in January 2031, but astronomers have a decade to plan for that approach. If history is any guide, telescopes around the world and in space, along with any spacecraft that happen to be nearby, will peer at the comet to learn as much as possible about its composition and history.
Comet Bernardinelli-Bernstein is estimated to be about 1000 times more massive than a typical comet, making it arguably the largest comet discovered in modern times. It has an extremely elongated orbit, journeying inward from the distant Oort Cloud over millions of years. It is the most distant comet to be discovered on its incoming path.
LCO's LOOK Project, which already observes several comets, will continue to watch Bernardinelli-Bernstein. It is expected to be of help since its network of telescopes allows for a "rapid response" within 15 minutes whenever any outbursts occur, the statement said. But LCO scopes won't be the only ones watching. "There are now a large number of surveys, such as the Zwicky Transient Facility and the upcoming Vera C. Rubin Observatory, that are monitoring parts of the sky every night," LOOK member Tim Lister, an LCO staff scientist, said in the same statement. "These surveys can provide alerts if one of the comets changes brightness suddenly," he added. "Then we can trigger the robotic telescopes of LCO to get us more detailed data, and a longer look at the changing comet while the survey moves onto other areas of the sky."
See the original article by Elizabeth Howell, with numerous links, at
https://www.space.com/giant-comet-bernardinelli-bernstein-activity-beyond-saturn
Thanks to Duncan Steel for passing along the link.
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C/2014 UN271 is a 19th magnitude object -- around one millionth the brightness of the faintest star visible by eye -- moving slowly in the constellation of Horologium, a few degrees north-east of Achernar.
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9. Variable Star News
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This month we feature the southern Long Period Variable (LPV) star RV Cen which has been highlighted in the AAVSO July 2021 Community Communication. It has been noted there that the frequency of observations of this star has been dropping away. This is a pity when the star has been under observation since December 1918. The star was observed regularly by the famous visual observer Albert Jones of Nelson. It has also been followed by Variable Stars South observer Peter Williams for a number of years, who to date has contributed just over 1000 observations to the database.
The convenor of the LPV group, Rich Roberts, has called for observers to pay more attention to RV Cent star so that the continuity of observation can be maintained The star is located in the area of the popular variable stars R Cen and T Cen and so could easily be added to the routine observation list of observers of those stars; at maximum magnitude range 7.0 to 10.8 it requires only a modest aperture to observe it. It could also be a project for some new observers. The period from maximum to maximum is greater than a year, ranging from 434 to 457 days (mean 446.5 days).
RV Cen is a Mira type variable, an example of the red giant class of stars which can display a variety of different characteristics. RV Cen has an amplitude in brightness that is quite small (usually about 2 to 3 magnitude units) and this has been attributed to a thin dust shell compared with Mira variables with considerably greater amplitudes. Despite the small amplitude the magnitude change does appear to vary noticeably with time (refer graph in the article), a good reason to take an interest in this star.
For more information on the light curve of this star see the AAVSO RV Cen article https://www.aavso.org/lpv-month
-- Alan Baldwin
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10. Conference: Dark and Quiet Skies for Science and Society – II
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The Conference “Dark and Quiet Skies for Science and Society”, jointly organized by the United Nations Office for Outer Space Affairs (UNOOSA), the Government of Spain and the International Astronomical Union (IAU), should have taken place in October 2020, but, because of the COVID-19 pandemic, it has been postponed and is now scheduled in Santa Cruz de La Palma, Canary Islands, Spain, from 3 to 7 October 2021.
However, because of the urgency to protect the right of humankind to access an uncontaminated night sky, both for its intrinsic cultural value and for the progress of science, the organizers decided to hold an on-line Workshop, on the same theme as the originally planned Conference.
The rationale for the Workshop and Conference relates to exponential deployments of technological developments, like urban illumination by LED, the large constellations of satellites in low Earth orbit and the high power radio transmission, which are creating unprecedented threats to the visibility of the pristine night sky and call for effective and prompt mitigating measures before the damage may become irreversible.
For details see http://research.iac.es/congreso/quietdarksky2021/pages/home.php
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11. IAU Statement on Climate Change
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The IAU calls on our community to develop and implement specific actions to help achieve the aims of the 2016 Paris Agreement on climate change. The study of astronomy provides all citizens a unique perspective and view of the Universe that highlights the fragility of life on planet Earth. The first Kavli–IAU interdisciplinary symposium will be dedicated to climate change on planets in late 2022 or early 2023.
The International Astronomical Union (IAU) joins other astronomy institutions and scientific organisations in stressing the importance and urgency of environmental sustainability for the future of our planet. As concluded by the International Panel on Climate Change (IPCC) and highlighted in many scientific reports, increases in anthropogenic carbon dioxide and other greenhouse gases have exacerbated climate change since the industrial revolution, and without mediation, we risk extreme and irreversible damage to life on our planet. The IAU calls on our community to develop, promote and implement specific actions to help achieve the aims of the 2016 Paris Agreement.
The study of astronomy provides all citizens a unique perspective and view of the Universe that highlights the fragility of Earth’s biosphere. Additionally, through comparative studies of planetary atmospheres, astronomers can model and measure the impact of greenhouse gases and their consequences for climate and climate change on planets.
The IAU applauds and acknowledges the steps its members are already taking to help protect our climate — from individual organizations that publish their own carbon budgets, to organisations like Astronomers for Planet Earth. The IAU, through its four Offices (OAD, OAO, OYA, OAE), strongly encourages and supports teaching and communicating about the Earth’s climate and the consequences of human activity, and we urge our national and individual members to address climate change in connection with their scientific, educational, outreach, and other societal activities.
As one step towards addressing this global problem, the IAU will issue a special call for the first Kavli–IAU interdisciplinary symposium, dedicated to Climate and Climate Change on Planets, to take place in late 2022 or early 2023. The symposium will draw from members of the IAU as well as other relevant unions (such as GeoUnions). One goal of the symposium will be to produce an IAU Springboard for Climate Action, directed to the astronomy community, that will recommend mitigating actions that can be undertaken at the individual, institutional, and IAU level.
For details see: https://www.iau.org/news/pressreleases/detail/iau2105/
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12. NASA Exoplanet Watch Seeks Observers
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We are writing to announce that Exoplanet Watch is now inviting astronomers to participate actively in the project. Exoplanet Watch is a new exoplanet citizen science project funded by NASA’s Universe of Learning and led by NASA’s Jet Propulsion Laboratory.
Exoplanet Watch relies on university astronomy students and amateur astronomers using ground-based telescopes to make observations of transiting exoplanets. This will help keep mid-transit times fresh. With more accurate timing, large observatories and space-based telescopes can make efficient use of valuable telescope time.
The Exoplanet Watch website lists nightly observation targets, but any exoplanet transit observations will work. Light curves generated by Exoplanet Watch are shared with the American Association of Variable Star Observers (AAVSO). Observers and data analysts are given credit for their work in any scientific papers resulting from their contributions.
For more information about Exoplanet Watch, visit our website at https://exoplanets.nasa.gov/exoplanet-watch/about-exoplanet-watch/overview/
Tiny URL: https://go.nasa.gov/3i0UvAI
Join our Slack Workspace to meet our team and ask questions.
http://uol-ets.slack.com
If you are interested in participating in Exoplanet Watch, please email exoplanetwatch@jpl.nasa.gov to let us know. Feel free to share this email with other astronomers who may be interested in participating as well.
We look forward to studying exoplanets with you!
Sincerely, Dr. Rob Zellem and Rachel Zimmerman Brachman
On behalf of the Exoplanet Watch team
exoplanetwatch@jpl.nasa.gov
https://exoplanets.nasa.gov/exoplanet-watch
-- Thanks to Tim Banks for passing on this request.
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13. Asteroid Rutherford
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The International Astronomical Union's Working Group on Small Bodies Nomenclature (Bulletin 1 No 1, published 14th May 2021) gazetted an asteroid in honour of Rutherford. The asteroid shows only as an unresolved light in reflected sunlight. It is expected to be about 10km diameter, well out in the asteroid belt (average distance 3.04AU), with a fairly circular orbit (e=0.09), and with an orbital period of 5.3 years.
The proposers were Alan and Pam Gilmore who first discovered it on 1981 April 3. Alan and Pam are astronomers associated with the Mt John Observatory, New Zealand, ran by the University of Canterbury, Rutherford's old university from which he has 5 degrees (BA, MA(Hons) BSc, PhD and PhD(Hon). Alan and Pam have discovered 41 asteroids between 1981 and 2003. They never hunted asteroids but discovered them whilst studying Near Earth Objects (NEO) in pre-CCD days. To the discoverer goes the honour of suggesting a name for each, but they cannot use their own names. Alan and Pam have named nineteen of their asteroids so far, using names like Aotearoa, Aoraki, Canterbury plus various New Zealand astronomers they knew. See their total at https://www.minorplanetcenter.net/iau/lists/MPDiscsAlpha.html
The entry states: (5311) Rutherford = 1981 GD1 Discovery: 1981-04-03 / A. C. Gilmore, P. M. Kilmartin / Lake Tekapo / 474
Ernest Rutherford (1871–1937), born and educated in New Zealand, won the 1908 Nobel Prize for Chemistry for his work on radioactive disintegration of elements. He was the first to develop radioactive dating of the Earth, established the nuclear atom, and predicted the existence of the neutron.
Note that an earlier asteroid named Rutherfordia was named after the town in New York State. It is often wrongly assumed to be named after Ernest Rutherford.
-- Copied from John Campbell's Rutherford website, https://www.rutherford.org.nz/hrodd.htm .
Our thanks to John for help with the citation. - Alan & Pam.
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14. New Type of Stardust
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New type of stardust may unlock solar system secrets. A newly-discovered type of star dust is helping scientists reveal what ingredients went into the formation of our solar system, more than 4.5 billion years ago. The tiny mineral grains from meteorites are at the centre of just-published findings, led by Kiwi and US scientists, challenging existing models of solar system formation at the chemical level.
The research, featured in major journal Science Advances, also demonstrate the complexity of what are called "primitive meteorites" such as the well-known and studied Allende meteorite, which fell to Earth in Mexico in February 1969. "Primitive meteorites are rare because they are the bits and pieces left flying around that haven't been incorporated into planets," said the study's co-author, Dr Bruce Charlier of Victoria University. "So they hold clues about some of those very early processes."
Charlier said these stellar remnants were made up of a number of different components that had different histories, and were formed under different conditions. Some of the components were actually splashes of melt formed during impacts of asteroids, but the very oldest components in the mix were called calcium-aluminium inclusions (CAIs). "It is widely thought these were condensed from a high-temperature gas as the Sun was forming," Charlier said. "This makes them very different from minerals you might find in an igneous rock on Earth, which crystallised from a magma."
In their paper, Charlier and his colleagues at the California Institute of Technology (Caltech) and the University of Chicago describe evidence of pre-solar grains found within the CAIs themselves. This showed the process was more complex than previously thought. Research into CAIs and meteorite composition is highly technical and detailed work, requiring specialist scientific instruments.
Charlier and his team have been splitting the CAIs into even smaller components – or the astronomical equivalent of the Russian Matroyoshka stacking dolls. They deploy a chemical process called step-leaching to incrementally dissolve the components of the CAIs in different strengths of acid, and then study the different fractions using a thermal-ionisation mass spectrometer.
"Step-leaching is a little bit of a blunt instrument because you are not entirely sure what exactly it is you are destroying at each step," he said. "But the nub of what we've found is, once you have stripped away 99 per cent of the common components within the CAIs, what we are left with is something highly exotic that we weren't expecting. "Those highly resistant materials are, we think, tiny pre-solar grains pre-dating our solar system, because when you measure their isotopic and chemical composition on the mass spectrometer they are very, very different to anything else you find.
Many carried unusually high amounts of strontium-84, or Sr-84, which was a relatively rare light isotope of the element strontium. "Strontium-84 is part of a family of isotopes produced by a nucleosynthetic process, named the p-process, which remains mysterious," said co-author and Caltech geochemist Associate Professor Francois Tissot. "Our results point to the survival of grains possibly containing pure strontium-84. This is exciting, as the physical identification of such grains would provide a unique chance to learn more about the p-process."
The grains carrying this signature, the researchers concluded, must have formed prior to the birth of the solar system and survived that cataclysmic process during which stellar grains were heated to extremely high temperatures, vaporised, and then condensed into solid materials.
Given the relative abundance of strontium-84, the discovery pointed to the likely existence in meteorites of nanometre-sized grains containing almost pure strontium-84 that were formed during a rare nucleosynthetic process before the formation of the solar system itself. The nature of these grains was still a mystery, as only their isotopic composition in strontium revealed their existence. But the high levels of Sr-84 favoured a scenario in which Earth accreted with more water and volatile elements, which were subsequently lost within the first few million years after their formation.
The scientists estimated the pre-solar grains were aged somewhere between 4.567 billion years old, when the solar system was formed, and 13.8 billion years old, about the time of the Big Bang, and represented the vestiges of material left over from the birth of the solar system.
Charlier's research was being supported by a $624,000 Marsden Fund grant.
See Jamie Morton's original NZ Herald article at
https://www.nzherald.co.nz/nz/new-type-of-stardust-may-unlock-solar-system-secrets/FRQ5BBUEUAASZSAQIKGMVXCVLQ/
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15. Quote
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"Scientific theories are not perfect replicas of reality, but we have good reason to believe that they capture significant elements of it. And experience reminds us that when we ignore reality, it sooner or later comes back to bite us." -- Naomi Oreskes in 'Scientific American' July 2021, p.72.
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Alan Gilmore Phone: 03 680 6817
P.O. Box 57 alan.gilmore@canterbury.ac.nz
Lake Tekapo 7945
New Zealand
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December Celestial Calendar by Dave Mitsky
July Celestial Calendar by Dave Mitsky
All times, unless otherwise noted, are UT (subtract four hours and, when appropriate, one calendar day for EDT)
7/1 Last Quarter Moon occurs at 21:11
7/3 The Curtiss Cross, an X-shaped clair-obscur illumination effect located between the craters Parry and Gambart, is predicted to be visible at 11:24; Venus is 0.4 degrees north-northeast of the bright open cluster M44 (the Beehive Cluster or Praesepe) in Cancer at 12:00
7/4 Venus is at its northernmost latitude from the ecliptic plane (3.4 degrees) at 3:00; the Moon is 1.9 degrees south-southeast of Uranus at 18:00; Mercury is at its greatest western elongation (22 degrees) at 20:00
7/5 The Moon is at apogee; subtending 29' 29" from a distance of 405,341 kilometers (251,867 miles) at 14:47; Earth is at aphelion (152,100,527 kilometers from the Sun) at 22:00
7/6 The Moon is 5.0 degrees southeast of the bright open cluster M45 (the Pleiades or Subaru) in Taurus at 4:00; the Moon is 5.4 degrees north of the first-magnitude star Aldebaran (Alpha Tauri) at 22:00; the Moon is at the ascending node (longitude 70.5 degrees) at 23:00
7/8 The Moon is 3.7 degrees north of Mercury at 4:00; the Moon is 1.0 degrees north of the bright open cluster M35 in Gemini at 19:00
7/10 New Moon (lunation 1219) occurs at 1:17; the Moon is 6.7 degrees south of the first-magnitude star Castor (Alpha Geminorum) at 8:00; the Moon is 3.2 degrees south of the first-magnitude star Pollux (Beta Geminorum) at 13:00
7/11 The Moon is 3.1 degrees north-northeast of M44 at 15:00
7/12 The Moon is 3.1 degrees north-northeast of Venus at 12:00; the Moon, Venus, and Mars lie within a circle with a diameter of 3.6 degrees at 12:00; the Moon 3.6 degrees north-northeast of Mars at 13:00
7/13 Mars is at aphelion (1.6660 astronomical units from the Sun) at 00:00; the Moon is 4.6 degrees north-northeast of the first-magnitude star Regulus (Alpha Leonis) at 9:00; Venus is 0.5 degrees north-northeast of Mars at 14:00; Mercury is 2.2 degrees south of M35 at 15:00
7/16 The Lunar X, also known as the Werner or Purbach Cross, an X-shaped clair-obscur illumination effect involving various rims and ridges between the craters La Caille, Blanchinus, and Purbach, is predicted to be fully formed at 23:02
7/17 The Moon is 5.7 degrees north-northeast of the first-magnitude star Spica (Alpha Virginis) at 10:00; First Quarter Moon occurs at 10:11; the S-type asteroid 6 Hebe (magnitude +8.4) is at opposition in Aquila at 11:00; Pluto is at opposition (apparent size 0.1", magnitude +14.3) at 23:00
7/18 The B-type asteroid 2 Pallas (magnitude +9.7) is stationary in Pisces at 20:00
7/19 Mercury is at the ascending node through the ecliptic plane at 9:00
7/20 Mercury is at its northernmost declination (22.9 degrees) today; the Moon is at the descending node (longitude 249.8 degrees) at 13:00; the Moon is 4.5 degrees north-northeast of Antares at 15:00; the Sun enters Cancer, at longitude 118.3 degrees on the ecliptic, at 19:00
7/21 The Moon is at perigee, subtending 32' 47" at a distance of 364,523 kilometers (226,503 miles) at 10:24
7/22 Venus is 1.1 degrees north-northeast of Regulus at 4:00; the Sun's longitude is 120 degrees at 14:00
7/23 Mercury is 9.3 degrees south of Castor at 21:00
7/24 Mercury is at perihelion (0.3075 astronomical units from the sun) at 1:00; Full Moon, known as the Hay or Thunder Moon, occurs at 2:37; the Moon is 3.7 degrees southeast of Saturn at 19:00
7/25 Mercury is 5.7 degrees south of Pollux at 4:00; the equation of time, which yields the difference between mean solar time and apparent solar time, is at a minimum of -6.55 minutes at 23:00
7/26 The Moon is 3.9 degrees southeast of Jupiter at 5:00
7/27 The Moon is 3.8 degrees southeast of Neptune at 22:00
7/29 The peak of the Southern Delta Aquarid meteor shower (a zenithal hourly rate of 20 per hour) is predicted to occur at 5:00; a double Galilean satellite shadow transit (Callisto's shadow precedes Io's) begins at 20:06
7/30 Mars is 0.6 degrees north-northeast of Regulus at 2:00; the S-type asteroid 12 Victoria (magnitude +8.8 ) is at opposition in Aquila at 13:00
7/31 Last Quarter Moon occurs at 13:16; Mercury is 0.4 degrees north-northeast of M44 at 17:00
Friedrich Bessel (1784-1846) was born this month.
The light from Supernova SN 1054 was first noted by Chinese astronomers on July 4, 1054. The first lunar map was drawn by Thomas Harriot on July 26, 1609. Charles Messier discovered the globular cluster M28 in Sagittarius on July 27, 1764. Comet D/1770 L1 (Lexell) passed closer to the Earth than any comet in recorded history on July 1, 1770. Charles Messier discovered the globular cluster M54 in Sagittarius on July 24, 1778. Caroline Herschel discovered the open cluster NGC 6866 in Cygnus on July 23, 1783. The globular cluster NGC 6569 in Sagittarius was discovered by William Herschel on July 13, 1784. Karl Ludwig Hencke discovered asteroid 6 Hebe on July 1, 1847. The first photograph of a star, namely Vega, was taken on July 17, 1850. The first photograph of a total solar eclipse was taken on July 28, 1851. Hendri Deslandres invented the spectroheliograph on July 24, 1853. Sinope, one of Jupiter’s many satellites was discovered by Seth Nicholson on July 21, 1914. Karl Jansky announced the detection of radio radiation from the center of the Milky Way on July 8, 1933. Seth Nicholson discovered Neptune’s satellite Lysithea on July 6, 1938. The Mariner 4 probe took the first close-up image of another planet, namely Mars, on July 14, 1965. The Apollo 11 lunar module landed on the Moon on July 20, 1969. Neptune’s satellites Despinea and Galatea are discovered using images from the Voyager 2 probe on July 27, 1989. Fragments of Comet D/1993 F2 (Shoemaker-Levy) impacted Jupiter on July 16, 1994. Prospero, one of the satellites of Uranus, is discovered by Matthew Holman on July 18, 1999. Pluto’s satellite Styx is discovered using images from the New Horizon probe on July 11, 2012.
The peak of the Southern Delta Aquarid meteor shower on the morning of July 29th is compromised by moonlight from a waning gibbous Moon. The radiant is located northwest of the first-magnitude star Fomalhaut (Alpha Piscis Austrini). Jupiter lies about four degrees north of the radiant this year. Southern hemisphere observers are favored. Click on https://earthsky.org/.../everything-you-need-to-know.../ for further information. The Alpha Capricornids, the Piscis Austrinids, and the Northern Delta Aquarids are the other minor meteor showers with southern radiants occurring this month. A list of the year's meteor showers appears on page 254 of the RASC's Observer's Handbook 2021.
Information on passes of the ISS, the USAF’s X-37B, the HST, Starlink, and other satellites can be found at http://www.heavens-above.com/
The Moon is 20.4 days old, is illuminated 60.4%, subtends 30.2 arc minutes, and is located in Pisces on July 1st at 0:00 UT. The Moon is at its greatest northern declination of +25.5 degrees on July 9th and its greatest southern declination of -25.5 degrees on July 23rd. Longitudinal libration is at a maximum of +6.2 degrees on July 27th and a minimum of -5.6 degrees on July 14th. Latitudinal libration is at a maximum of +6.6 degrees on July 27th and a minimum of -6.7 degrees on July 14th. Favorable librations for the following lunar features occur on the indicated dates: Crater Lagrange on July 8th, Crater Belkovich on July 22nd, Mare Humboldtianum on July 23rd, and Crater Compton on July 24th. New Moon takes place on July 20th. The Moon is at apogee (a distance 63.55 Earth-radii) on July 5th and at perigee (distance 57.15 Earth-radii) on July 21st. Browse http://www.lunar-occultations.com/iota/iotandx.htm for information on lunar occultation events. Visit https://saberdoesthestars.wordpress.com/.../saber-does.../ for tips on spotting extreme crescent Moons and https://curtrenz.com/moon.html for Full Moon and other lunar data. Browse https://skyandtelescope.org/wp-content/uploads/MoonMap.pdf and https://nightsky.jpl.nasa.gov/docs/ObserveMoon.pdf for simple lunar maps. Click on http://astrostrona.pl/moon-map for an excellent online lunar map. Visit http://www.ap-i.net/avl/en/start to download the free Virtual Moon Atlas. Consult http://time.unitarium.com/moon/where.html for current information on the Moon and https://www.fourmilab.ch/earthview/lunarform/lunarform.html for information on various lunar features. See https://svs.gsfc.nasa.gov/4874 for a lunar phase and libration calculator and https://quickmap.lroc.asu.edu/... for the Lunar Reconnaissance Orbiter Camera (LROC) Quickmap. Click on https://www.calendar-12.com/moon_calendar/2021/july for a lunar phase calendar for this month. Times and dates for the lunar crater light rays predicted to occur this month are available at http://www.lunar-occultations.com/rlo/rays/rays.htm
The Sun is located in Gemini on July 1st. The Earth is farthest from the Sun, a distance of 1.0167 astronomical units, on July 5th. On that date, it is 3.3% more distant than it was at perihelion and 1.7% farther than its average distance. The Sun enters Cancer on July 20th.
Brightness, apparent size, illumination, distance from the Earth in astronomical units, and location data for the planets and Pluto on July 1st: Mercury (+0.8 magnitude, 8.8", 27% illuminated, 0.77 a.u., Taurus), Venus (-3.8 magnitude, 11.2", 90% illuminated, 1.49 a.u., Cancer), Mars (+1.8 magnitude, 3.9", 97% illuminated, 2.43 a.u., Cancer), Jupiter (-2.6 magnitude, 45.3", 99% illuminated, 4.36 a.u., Aquarius), Saturn (+0.4 magnitude, 18.3", 100% illuminated, 9.09 a.u., Capricornus), Uranus (+5.8 magnitude, 3.5", 100% illuminated, 20.08 a.u. on July 16th, Aries), Neptune (+7.9 magnitude, 2.3", 100% illuminated, 29.39 a.u. on July 16th, Aquarius), and Pluto (+14.3 magnitude, 0.1", 100% illuminated, 33.37 a.u. on July 16th, Sagittarius).
Venus and Mars are in the west and Jupiter and Saturn are in the east during the evening. At midnight, Jupiter and Saturn are in the southeast, and Neptune is in the east. In the morning, Mercury and Uranus can be found in the east, Jupiter and Neptune in the south, and Saturn in the southwest.
On July 4th, Mercury achieves greatest western elongation. A waning crescent Moon passes four degrees north of the planet on the morning of July 8th. Mercury is at its most northerly latitude from the ecliptic plane on July 20th and is at perihelion on July 24th.
Venus changes very little in brightness, apparent size, and illumination during July. Venus increases in solar elongation from 25 to 33 degrees but a 12-degree decline in declination leaves it poorly placed. The brightest planet passes north of the open cluster M44 on July 3th and is at its greatest northern latitude the next day. Venus and Mars both travel southeastward through Leo this month coming within 0.5 degrees of each other on July 13th. The waxing crescent Moon passes three degrees north of the two rocky planets on July 11th and July 12th. Venus passes about four degrees south of the barred-spiral galaxy M95 on July 27th.
Mars is only 3.7 arc seconds in apparent size and, at magnitude +1.8, is near its minimum brightness. Its elongation from the Sun decreases from 33 to 22 degrees this month. The waning gibbous Moon passes two degrees south of the Red Planet on July 11th. Mars is at aphelion on July 13th and is also 0.5 degrees south of Venus on that date. Mars enters Leo in mid-July. It passes less than one degree north of Regulus on July 29th.
Jupiter rises before midnight as it retrogrades through Aquarius this month. It subtends 48.4 arc seconds and shines at magnitude -2.8 on the final day of July. A waning gibbous Moon passes less than four degrees to the south of the gas giant planet on the night of July 25th/26th. Callisto and the shadow of Europa both transit Jupiter on the morning of July 25th. Io disappears into eclipse not long afterwards. A double Galilean shadow transit involving the shadows of Callisto and Io takes place from some parts of the world on July 29th. Information on Great Red Spot transit times and Galilean satellite events is available on pages 50 and 51 of the July 2021 issue of Sky & Telescope and online at http://www.skyandtelescope.com/.../interactive-sky.../ and https://www.projectpluto.com/jevent.htm
Saturn rises around 10:00 p.m. local time and reaches the meridian about 3:00 a.m. local time on July 1st. It brightens to magnitude +0.2 and subtends 18.6 arc seconds by the end of July. Its rings span 42 arc seconds. Saturn passes one arc minute north of the faint barred-spiral galaxy IC 1339 on the night of July 4th/July 5th. On July 24th, the Full Moon passes four degrees south of the Ringed Planet. Saturn's largest and brightest satellite Titan (magnitude +8.5) lies due north of Saturn on July 2nd and July 18th and due south of the planet on July 10th and July 26th. When the faint Saturnian satellite Iapetus attains western elongation on July 4th, it's positioned nine arc minute due west of Saturn and shines at tenth magnitude. For further data on Saturn’s satellites, browse http://www.skyandtelescope.com/.../interactive-sky.../
Uranus is located 12 arc minutes due north of the sixth-magnitude star Omicron Arietis on July 1st. By July 31st, the ice giant planet has traveled to a position almost one degree northeast of the star. A waning crescent Moon passes less than five degrees southeast of Uranus on July 4th. Visit http://www.nakedeyeplanets.com/uranus.htm for a finder chart.
Neptune rises around local midnight as it retrogrades through eastern Aquarius. The eighth planet is located about six degrees east of the fourth-magnitude star Phi Aquarii and very close to the seventh-magnitude field star HIP 116402. A gibbous Moon passes eight degrees southwest of Neptune on July 27th. Browse http://www.nakedeyeplanets.com/neptune.htm for a finder chart.
The dwarf planet Pluto reaches opposition on July 15th. Finder charts can be found on pages 48 and 49 of the July 2021 issue of Sky & Telescope and on page 243 of the RASC Observer’s Handbook 2021. An article on observing Pluto appears on pages 46 to 49 of the July issue of Astronomy.
For more on the planets and how to locate them, browse http://www.nakedeyeplanets.com/
The periodic comet 4P/Faye travels northeastward through Aries during July. The tenth-magnitude comet passes less than two degrees to the north of Uranus on July 18th and July 19th. Visit http://cometchasing.skyhound.com/ and http://www.aerith.net/comet/future-n.html and https://cobs.si/ for information on comets visible this month.
Asteroid 4 Vesta heads southeastward from Leo into Virgo this month. The main belt asteroid lies within one degree of the fifth-magnitude star Pi Virginis for five nights centered on July 13th. It passes 20 arc seconds south of the spiral galaxy M61 on July 27th. Asteroid 6 Hebe (magnitude +8.4) is at opposition on July 17th and asteroid Victoria (magnitude +8.8 ) is at opposition on July 30th. Information on asteroid occultations taking place this month is available at https://www.asteroidoccultation.com/2021_07_si.htm
A wealth of current information on solar system celestial bodies is posted at http://nineplanets.org/ and http://www.curtrenz.com/astronomy.html
Information on the celestial events transpiring each week can be found at https://stardate.org/nightsky and http://astronomy.com/skythisweek and http://www.skyandtelescope.com/observing/sky-at-a-glance/
Data on current supernovae can be found at http://www.rochesterastronomy.org/snimages/
Free star maps for July can be downloaded at http://www.skymaps.com/downloads.html and https://www.telescope.com/content.jsp... and http://www.kenpress.com/index.html
Finder charts for the Messier objects and other deep-sky objects are posted at https://freestarcharts.com/messier and https://freestarcharts.com/ngc-ic and https://www.cambridge.org/.../seasonal_skies_july-september
Telrad finder charts for the Messier Catalog are posted at http://www.custerobservatory.org/docs/messier2.pdf and http://www.star-shine.ch/.../messiercharts/messierTelrad.htm
Telrad finder charts for the SAC’s 110 Best of the NGC are available at http://sao64.free.fr/observat.../catalogues/cataloguesac.pdf
Freeware sky atlases can be downloaded at http://www.deepskywatch.com/.../Deep-Sky-Hunter-atlas... and http://astro.mxd120.com/free-star-atlases
Information pertaining to observing some of the more prominent Messier galaxies can be found at http://www.cloudynights.com/.../358295-how-to-locate.../
Author Phil Harrington offers an excellent freeware planetarium program for binocular observers known as TUBA (Touring the Universe through Binoculars Atlas), which also includes information on purchasing binoculars, at http://www.philharrington.net/tuba.htm
Stellarium and Cartes du Ciel are two excellent freeware planetarium programs that are available at http://stellarium.org/ and https://www.ap-i.net/skychart/en/start
Deep-sky object list generators can be found at http://www.virtualcolony.com/sac/ and http://tonightssky.com/MainPage.php and https://dso-browser.com/
The multiple star 36 Ophiuchi consists of three orange dwarf stars. For more on this interesting system, see https://stardate.org/radio/program/orange-triplets and http://www.solstation.com/stars/36ophiu3.htm
Forty binary and multiple stars for July: Eta Draconis, 17 & 16 Draconis, Mu Draconis, Struve 2273, Nu-1 & Nu-2 Draconis, Psi Draconis (Draco); Kappa Herculis, Gamma Herculis, Struve 2063, 56 Herculis, Struve 2120, Alpha Herculis (Ras Algethi), Delta Herculis, Rho Herculis, Mu Herculis (Hercules); Rho Ophiuchi, Lambda Ophiuchi, 36 Ophiuchi, Omicron Ophiuchi, Burnham 126 (ADS 10405), Struve 2166, 53 Ophiuchi, 61 Ophiuchi (Ophiuchus); h5003 (Sagittarius); Xi Scorpii, Struve 1999, Beta Scorpii, Nu Scorpii, 12 Scorpii, Sigma Scorpii, Alpha Scorpii (Antares), h4926 (Scorpius); Struve 2007, 49 Serpentis, Struve 2031 (Serpens Caput); 53 Serpentis, Struve 2204, h4995, h2814 (Serpens Cauda); Epsilon Ursae Minoris (Ursa Minor)
Notable carbon star for July: T Draconis
Sixty-five deep-sky objects for July: NGC 6140, NGC 6236, NGC 6340, NGC 6395, NGC 6412, NGC 6503, NGC 6543 (Draco); IC 4593, M13, M92, NGC 6106, NGC 6166, NGC 6173, NGC 6181, NGC 6207, NGC 6210, NGC 6229, NGC 6482 (Hercules); B61, B62, B63, B64, B72, IC 4634, IC 4665, LDN 42, LDN 1773, M9, M10, M12, M14, M19, M62, M107, NGC 6284, NGC 6287, NGC 6293, NGC 6304, NGC 6309, NGC 6356, NGC 6366, NGC 6369, NGC 6384, NGC 6401, Tr 26 (Ophiuchus); NGC 6440, NGC 6445 (Sagittarius); B50, B55, B56, Cr 316, M4, M6, M7, M80, NGC 6144, NGC 6153, NGC 6192, NGC 6231, NGC 6242, NGC 6302, NGC 6337, NGC 6451 (Scorpius); NGC 6217, NGC 6324 (Ursa Minor)
Top ten binocular deep-sky objects for July: IC 4665, LDN 1773, M4, M6, M7, M10, M12, M13, M92, NGC 6231
Top ten deep-sky objects for July: M4, M6, M7, M10, M12, M13, M92, NGC 6210, NGC 6231, NGC 6543
Challenge deep-sky object for July: NGC 6380 (Scorpius)
The objects listed above are located between 16:00 and 18:00 hours of right ascension.
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Minor Planet Occultation Updates:
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Quaroa
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Groups.io
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WellingtonAstronomers@groups.io
AucklandAstronomers
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AucklandAstronomers@groups.io
North Island Astronomers
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NorthIslandAstronomers@groups.io
South Island Astronomers
https://groups.io/g/SouthIslandAstronomers
SouthIslandAstronomers@groups.io
NZAstrochat
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NZAstrochat@groups.io
NZ Photographers And Observers
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NZPhotographers@groups.io
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Please note:
My standard caveat that these are the views of a learned amateur, not a professional in the sector, applies as always.
The above post/email/update represents my own words, views, research and opinions, unless stated otherwise the above work
represents my own writing. I’ll give credit or thanks if I have used or represented other people’s words and/or opinions.
The links and references listed below represent the work and research of the respective author’s.
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