Astronomy Cafe – Jan 24, 2020

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Video transcript of meeting

  • JWST Report – Chris Gainor
    • Spacecraft now in orbit around L2
    • Telescope commissioning is now starting over the next six months
    • Cooling the onboard instruments is critical
  • Discussion about Black and White photography
    • B&W Gallery by John McDonald
    • Processing techniques converting digital colour images to black and white
  • Methods of Observing and Scientific Illustration
    • Photography – digital and analogue
    • Sketching – perhaps a new SIG?
    • Painting – watercolours
    • Observing vs art
  • Astrophotos – Brock Johnston
  • Missing RASC 2022 calendars – Chris Gainor
    • Shipping issues discussed at the national level
    • Calendars are now considered missing, so they will be reshipped
  • Recent and future astronomy presentations
    • Charles Ennis talk about cross-cultural asterisms to the FDAO Star Party last Saturday
    • Chinese Giant Solar Telescope – Les Welch
      • Ring design solar 1.8m telescope – 2010
      • Paul Hickson at UBC is working on this instrument
    • Speakers covering new subjects – Dave Payne to coordinate either a new SIG or ongoing discussion at Astro Cafe
  • FDAO Report – Lauri Roche
    • Calvin, Lauri and Sid are still doing outreach online to schools
    • Made 12 online sessions to Grade 10 classes over the last 2 weeks
    • Did an in-person session with Kindergarten and Grade 1 students once last week
    • NSERC grants haven’t been granted to FDAO as well as other deserving organizations
  • Pearson College Report – Bill Weir
    • International students are still in lockdown
    • Canadian students were sent home
    • College management is very nervous about their operation

Astronomy Cafe – Jan 17, 2022

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Transcript video of the meeting

Meeting notes

  • A Woman of Astronomy – Marji Welchframe
    • Urania, Muse of Astronomy
    • Seal of the RASC – “Quo Ducit Urania” (i.e. where Urania leads, we follow)
    • Urania is 1 of 9 Muses of the Arts in Greek Mythology
    • Uranometria star atlas by Johann Bayer (1603) – published and sold by Sky & Telescope (Willman Bell section)
  • Early computer memories
    • LGP-30 tube-based computer used at the University of Alberta in Edmonton by John McDonald in 1958
    • Reminisces from various members about early computers, calculators, slide rules, and other computing devices and programming languages they used decades ago.
  • Lunar Puzzles – Randy Enkin
    • 100-piece from NASA
    • 1000+ piece from Cobble Hill
    • 1000 piece from Four Point
    • 3-D printed Moon puzzle – Randy and his daughter assembled it
  • Reports  from Lauri Roche
    • 2022 RASC Calendars have still not arrived
    • Sky Cultures of the World: RASC World Asterisms Program – Charles Ennis, 1st VP with RASC National – FDAO Star Party – this Sat, Jan 22nd 7-9PM – available on Zoom and Youtube
    • Eclipses for 2023 and 2024 – Education & Public Outreach Committee task force headed by Randy Attwood. Thousands of eclipse glasses will be available and sent to RASC Centres. Members can participate on the committee – contact Lauri.
  • JWST Update – Chris Gainor
    • Mirror Segment Deployment Tracker – activating the actuators behind the mirror segments
    • JWST enters a halo orbit around L2 position this Sunday, Jan 23rd
  • Astro Cafe next week – Jan 24, 2022
    • Dr. Tanya Harrison, “a professional Martian” – our Astro Cafe speaker next week
    • David Lee will be hosting
  • Scarlett Caterpillar Club – a parasitic fungus Bill Weir found near the observatory at Pearson College

Extras

  • NASA 3D Resources – 3D models of equipment, models of celestial and solar system objects, space missions (like JWST). Various media for download: fly-throughs, interactive visualizations, 3D printer files, stereo images.

Astronomy Cafe – Jan 10, 2022

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Video transcript of meeting

  • Lunar sketching & movie review – Randy Enkin
    • Randy’s Lunar “scissors” sketch, compared with Mike Nash and Bill Weir photos of the same area
    • “Don’t Look Up” popular movie on Netflix
      • Amy Mainzer was the science advisor for the movie, and is also the Principal Investigator for NEOWISE. So the science was quite accurately portrayed in the movie.
      • Observation of Mars and Jupiter in 1802 – Piazzi discovered Ceres instead of a new planet, and Carl Friedrich Gauss computed the orbit of the asteroid
      • Measuring the Earth – Gauss and von Humbolt
      • JPL Horizons System (Solar System Dynamics) – solar system ephemeris computation system
      • Mark Boslough movie review – don’t read before watching the movie!
      • Brian Cox’s commentary about Don’t Look Up
  • Astrophotos from Edmonton Centre – Dave Robinson
    • Antimatter and Dark Matter cartoon
    • Michael Jäger (@Komet123Jager) photo of comet C/2021 A1 Leonard from Skygems Observatories in Nambia
    • Article explains why comet heads are green, but their tails are not green
    • Ursa Major and snow carving of a bear – Warren Findlay
  • UVic construction & Sunspots – Alex Schmid
    • UVic Construction photos – An update on two new buildings – residence, lecture halls, dining areas
    • Recent Sunspots – a-focal through eyepiece using a 5″ Newtonian telescope with solar filter
  • James Webb Space Telescope (JWST) – Chris Gainor
    • Launched on Ariane 5 – Dec 25, 2021
    • Journey from Earth to L2 Lagrange Point – deploying the telescope components
    • Final position at L2 – arrives Jan 23, 2022 (approximately)
    • First images should be released June, 2022
    • Discussion about single points of failure for the mission
    • JWST Control Subsystems
  • RASC National 2022 calendars – Lauri Roche
    • Our orders are on their way, but have still not arrived in Victoria
  • Victoria Centre Observatory Upgrade – Reg Dunkley
    • QHY 600 mono camera is now attached to the OGS 12.5″ telescope
    • New USB3 connection in place
    • Telescopes rebalanced for the new gear
    • Lots of snow still on the ground around our observatory
  • Our Astro Cafe speaker on Jan 24th will be Dr. Tanya Harrison, “a professional Martian”
  • FDAO Star Party – Jan 22nd – Lauri Roche
    • World Asterisms Project – Charles Ennis, 1st VP for RASC National
  • AGM – election – Chris Purse
    • Council openings are available – contact Reg Dunkley (Past President) if any member wishes to stand for Vice President, Secretary (or any other position) on Victoria Centre’s Council

President’s Message – Dec 2021

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Ah 2021. What a strange trip around the Sun! I am writing this letter on the day of the winter solstice. There is a waning gibbous moon shining high in the east, when I go to bed, and it is high in the west to greet me in the morning. I take great solace in watching and thinking about the dependable motion of the Earth through the Universe, while so much of life and news this year has left me feeling unsettled.

Randy Enkin using his sextant
Randy Enkin using his sextant

Nearly as dependable as the astronomical objects has been you, our astronomical community. I am so pleased when I see the 30 or 40 of us gather each Monday evening at our virtual Astro Café. We are an appreciative and supportive community. Look at all the different skill sets and experiences that get shared every week. And look at those beautiful photos and sketches that we have created. I particularly wish to mention the personal observatories (I know of 3!) that are getting designed and built by members of our centre, as well as the fantastic work by our technical committee in upgrading the Victoria Centre Observatory.

Our group has motivated me to try new astro-projects – whether observing sunspots with a solar telescope borrowed from the Centre (thanks to the capable curation of our telescope collection by Sid Sidhu), or star hopping to those faint fuzzies that you deep space observers like. And I love the expressions of appreciation when I show off my lunar sketches to our crowd.

Do remember that our community survives on the strength of our volunteerism. We have a specific requirement this year for a new secretary and a new vice president. Don’t feel you aren’t up to the job! I still feel like a newbie in the role of president, but there is no shortage of good council from the many past executives who continue to be active. Come join us on the inside, and you will feel even more affection for the Centre.

I wish us all a fruitful and fulfilling new year, with many clear skies.

Look Up,
Randy Enkin, President@Victoria.RASC.ca

Astronomy Cafe – Dec 20, 2021

Posted by as Astro Cafe

Video transcript of meeting

  • Updates – Chris Gainor
    • James Webb Space Telescope – launch on Dec 24th 4:20AM – NASA TV & Youtube live streaming
    • Parker Solar Probe – 5 min video from NASA
    • RASC Board of Directors reportNational office moved last week to College Street in central Toronto
      • RASC Centre orders for bulk 2022 Calendars – 7 centres have received their boxes, but delivery to BC centres may be delayed further
      • Observing certificates sent out today
  • Astrophotos – Ken McGill
    • Orion Nebula – ZWO 1600MC, ASI Air Live View
    • Andromeda Galaxy – Oct 30th 
    • Pleiades
  • My Astronomy Sketch of the Year 2021 – Dorothy Paul
    • Observed Nov 28-Dec 1, 2021 from the west side of Eureka Valley (NW corner of Death Valley National park)
    • Remote, dark (Mag 6.5) and cold (-5ºC)!
    • Sky Critters – Canis Major, Hydra, Leo, Ursa Major – sketched from memory, like being in a theatre
    • They had Dorothy’s Dobsonian telescope with them, but didn’t end up using it 
  • Astrophotos – Brian Barber
    • Full Moon – using a NexYZ for mounting a smartphone, PIP software to centre & size, AutoStakkert software to stack the photos
  • Building the MCD Observatory – Michel Michaud
    • Presentation to Club d’astronomie de Rimouski
    • Started July 26
    • 14′ long 4×4 timbers and special smaller door
    • Built cases over the exposed rails to protect from rain and ice
    • Paramount MX to arrive in Feb
    • Celestron Edge HD 14″ – March – Summer 2022
    • First projects
      • Photometry
      • Asteroids
    • Restarting his Pleiades project when the 14″ scope arrives
    • Currently using his Meade LX-55 mount and a 66mm refractor
  • Report on astronomy activities – Nathan Hellner-Mestelman
    • NerdAnomaly – online cartoons
    • Learning sketching at school
    • Casual public outreach – telescope setup on the sidewalk outside the house
  • Report on astronomy activities – David Lee
    • Pivoting to maintain community – formed Victoria Centre’s SIGs
    • Personal study – astrophotography, observing, space exploration
    • VCO Technical team – work to be ready when we can open to members again
    • FDAO – collaborations with UVic – Dave Payne, Mike Nash, Dan Posey, Brock Johnston
    • Variable Star Observing – completed 3 AAVSO certificates
    • Australian sketching workshop – Dorothy Paul

Victoria Centre needs a new Vice-President and Secretary for 2022 – to stand for election, please contact Randy Enkin or Reg Dunkley

Astronomy Café will resume on Monday, January 10, 2022

Astronomy Cafe – Dec 13, 2021

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Mission to Mars – Dr. Robert Thirsk

  • Deep space missions being planned – returning to lunar orbit, the Moon’s surface, and onward to Mars
  • Maintaining the health of astronauts will be a significant challenge to the missions
  • Mars atmosphere is thick enough to sustain windstorms
  • Surface is covered in iron oxide dust
  • International Space Exploration Coordination Group – planning for exploration of Mars
  • Lunar Gateway Spaceport to be built orbiting the Moon – build starts next year
    • Canadarm 3 – using AI, 8.5m long
    • JAXA (Japan), NASA (USA), ESA (Europe)
  • Deep Space Transport – flights from the Lunar Gateway spaceport, ultimately to Mars after test flights
  • 2030s – 2 cargo vehicles assembled in Earth orbit and flown to Mars
    • Mars Ascent Vehicle – lands on Mars
    • Facilities and crew quarters to be built
  • Mars Transfer Vehicle – astronauts travel from Earth orbit to Mars – a 6-month trip
  • Mars Base – crew quarters, nuclear reactor, supplies
  • Pressurized Mars Rover allowing crew to travel up to 100kms at 72,000 kmh
  • Crew will stay on Mars for 500 days
  • Due to the 20 minute communication delay, Mission Control’s role in the mission will be limited
  • Big issues
    • Extreme isolation
    • Medical emergencies – autonomous treatment is the only option, powered by AI, on-board medical lab analysis
    • Exercise facilities will be very small
    • Radiation shielding and a shielded safe area
  • Medical Tricorder – Star Trek – now a reality! Qualcomm Tricorder
  • Environmental monitoring of cabin conditions
  • Crew bio-monitoring – smart shirt
  • Medical technology developed for this mission can be deployed in remote areas of Canada, and even primary care can benefit

Q&A

  • Radiation limits dictate that astronauts can only go to Mars once
  • Advice to students interested in space missions: physics, math, but skills diversity is important, personality traits (work with diverse community), health and fitness is important. Be persistent – may take 7-8 attempts to be selected as a Canadian astronaut
  • Canadian clinical research and remote health care – could result in a key role in space health – CSA’s Health Beyond Initiative
  • Most physiological effects can be recovered from by astronauts, but can take a year or two. Ionizing radiation is the biggest issue.
  • Spinning the spacecraft to create gravity isn’t going to happen due to engineering limitations
  • Test missions to a Lagrange Point and a nearby asteroid
  • Shielding research – NASA/Johnson and ICRP (upcoming Vancouver meeting)
  • Lunar Gateway – private partners like SpaceX are being used by NASA
  • 2 flights for 2 Canadian missions to the Moon are in place – Artemis 1 and 2
  • Would JWST failure affect the Mars missions? Not really – the missions are separate.

Transcript video of the meeting

  • Edmonton astrophotos – Dave Robinson
    • Time lapse video over 2.5 hours – Arnold Rivera
  • Astrophotos – Dave Payne
    • Pleiades – pleased with the nebulosity
    • Owl Cluster NGC 457 – young star cluster
    • Cave Nebula – reprocessed using Dave’s new PixInsight script
  • Lauri Roche
    • Thanks to Jeff Pivnick for bring Dr. Thirsk to talk to us
    • Sat, Dec 18th – last FDAO Star Party – JWST speakers from the NRC
    • RASC National 2022 calendars have not yet arrived. Still a few available – contact Lauri.
  • Dec 22nd is the JWST scheduled launch update (see 60 Minutes) – Chris Gainor
  • Randy Enkin
    • RASC Victoria Centre 2022 calendar – a limited run, but 4 still available – view the gallery and contact Joe to order ($15 each)
    • Encourage members to talk to us at next week’s Astro Cafe – what interests you about astronomy?
    • Comparison of two comets: NEOWISE (last year) and Leonard (this year)
    • RASC Victoria Centre Council vacancies: 1st VP and Secretary
  • Maker’s SIG meeting online this Thursday – David Lee

The final Astro Café of 2021 will be held on Monday, December 20, 2021. Astro Café will resume on Monday, January 10, 2022.

Astronomy Cafe – Dec 6, 2021

Posted by as Astro Cafe

Transcript video of the meeting

  • Review next week’s presentation by Dr. Robert Thirsk – Chris Purse
    • Connection to meeting will be through a waiting room
    • Jeff Pivnick will host
    • Link for this meeting will be unique, and emailed to all RASC Victoria members
    • Maximum of 100 attendees
  • Total Solar Eclipse from Antarctica – Joe Carr
  • Astro Compass – Randy Enkin & Peter Kabel
    • Frank Younger’s estate donated the Compass Astro to Victoria Centre
    • Used in aircraft when they are flying a long way north, where the magnetic field isn’t reliable
    • “It’s a sundial in reverse”
    • Need to know your position and time, sighting on a celestial object with known Right Ascension & Declination. North will be indicated accurate to within about 1º.
  • Edmonton Astrophotos – Dave Robinson
    • Photo of Comet C/2001 A1 Leonard near M3 cluster – Arnold Rivera
    • Sketch of Comet C/2001 A1 Leonard with observing narrative – Berta Beltran
    • Rosette Nebula photo – Arnold Rivera
  • Chris Gainor
    • James Web Space Telescope update
      • Completed fuelling operations for the JWST itself
      • To be mounted onto the Ariane 5 rocket next
      • Dec 22nd launch date
      • Launch website
    • Not Yet Imagined – Chris’ new book about Hubble Space Telescope’s history. Book should be available for sale in awhile through RASC’s e-store and FDAO’s e-store locally. Electronic versions from NASA
  • Comet C/2001 A1 Leonard – observing report by David Lee
    • Observed and photographed through some clear spots over the last few days
    • Poor conditions for photography, but managed to get a good wide field image of the comet using a dSLR and tracking mount
    • Virtual Telescope broadcast – tomorrow 8PM PST
  • Lauri Roche
    • 2022 RASC Calendars
      • Send any more requests for calendars to Lauri
      • Should be $16 each
    • FDAO e-store – astronomy and space themed fun items available for sale. Free local delivery or shipped by mail (extra cost).

Astronomy Cafe – Nov 29, 2021

Posted by as Astro Cafe

Meeting transcript video

  • Astro Cafe hosting – Randy Enkin
    • John has resigned as a meeting host, so we need a new second host
    • Job description
      • Send meeting link to members on the Skynews list
      • Create a short slide show for Astrophotos from Edmonton
      • Keep a list of speakers and presenters for the evening
      • Host the online meeting
    • Contact Randy Enkin or Chris Purse for any questions about hosting or to volunteer
    • No Astro Cafe will be held on Dec 27th or Jan 3rd
  • 2022 RASC Calendars – Chris Purse and Lauri Roche
    • Delivery from National office is pending
    • Local delivery will be done by our volunteers
  • Dr. Laurie Rousseau-Nepton – profile by Marjie Welchframe
    • Canadian Women Astronomers series (have 9 more to present)
    • Indigenous woman from Quebec
    • Laval U – PhD
    • CFHT resident astronomer – 2017-present
    • SITELLE instrument – Fourier transform spectroscopy
    • SIGNALS – principal investigator – star formation survey
    • First Nations culture helps with conducting quality scientific research
    • NFB – she is finishing the film “The Northern Star” for high school students
  • Edmonton Astrophoto – Dave Robinson
    • Lunar Eclipse composite – Jan 21, 2019 & Nov 19, 2021 – Alister Ling
  • Astronomy & Space Book Reviews/Recommendations by members
    • Randy Enkin
      • The Apollo Murders by Chris Hadfield
      • Description of Apollo lunar missions – Chris Gainor
    • Martin Gisborne
      • Lunar Module at Grumman Factory photos
      • The Victorian Amateur Astronomer – 1820-1920 – by Alan Chapman – fascinating star parties and people, how photography changed astronomy
    • John McDonald
      • Lonely Hearts of the Cosmos by Dennis Overby
      • Empire of the Stars by Arthur J Miller
      • Miss Leavitt’s Stars by George Johnson
      • Decoding the Heavens by Jo Marchant
      • The Glass Universe – by Dava Sobel – transition to spectroscopy and variable stars
    • Derek Trimmer
      • Violent Universe ‘An eye-witness account of the commotion in Astronomy 1968-69’ by Nigel Calder, published by the BBC, 1969 – a mid-teenager favourite
    • David Lee
      • A History of the Universe in 100 Stars – Florian Freistetter (current)
      • The Hundred Greatest Stars Hardcover – Illustrated, June 19 2002 by James B. Kaler
    • Oliver Robinow 
      • The Perfect Machine – Ronald Florence, 1995 – building the Palomar telescope
    • Lauri Roche
    • Chris Gainor
      • When the Earth Had Two Moons – Erik Asphaug
      • Across the Airless Wilds – Earl Swift – about the lunar rover for the last 3 Apollo missions
      • Liftoff – Eric Berger – history of SpaceX
    • Garry Sedun
      • The Stars: A New Way to See Them – H. A. Rey (of Curious George fame)
      • The Last Stargazers – Emily Levesque
    • Neil Banera
      • A Manual For Amateur Telescope Makers – Jean-Marc Lecleire & Karine Lecleire (Willman Bell) – good descriptions of how to make corrections to mirror figures, tools to use, 3 telescope configurations
      • Meteorite Hunter: The Search for Siberian Meteorite Craters by Roy A. Gallant
  • Telescope Building with John Dobson – figuring mirrors on Youtube – Martin Gisborne
  • Astronomy Cafe – Chris Purse
    • Need another host for Astro Cafe – talk to Chris Purse
    • Need another person to video record the meeting (and take notes) for posting on Victoria Centre’s website and Youtube – talk to Joe Carr
    • We will need several hosts when we return to in-person, hybrid Astro Cafes in Fairfield
  • Chris Gainor
    • Hubble Update – only one instrument is still non-functional
    • JWST virtual launch event signup

Astronomy Cafe – Nov 22, 2021

Posted by as Astro Cafe

Video transcript of the meeting

  • Astrophotography SIG – intro by John McDonald
    • Special Interest Group meets on the 4th Wednesday of each month
    • Challenge project – processing the recent Plaskett data
    • Martin Gisborne – a short journey to astrophotography
      • Professional photographer – worldwide
      • Telescope shop tempted Martin while he lived in Paris
      • Lived close to the Ames Research Centre and Orion Telescopes in the Bay Area of California – more temptations and motivation
      • Review of his astronomy equipment acquisitions, processing software and apps
      • Refined his methodology over the last few years since moving to Canada
      • Reviewed early astrophotos and how they are progressing
      • The Deep-Sky Imaging Primer – Charles Bracken series of books
      • His Heart and Soul Nebula photo featured on the RASC Journal 
      • Pandemic supply chain issues a challenge to new amateur astronomers to acquire equipment
      • Photo show: Pleiades (M45), Triangulum Galaxy (M33), Heart Nebula (IC 1805), Hercules Cluster (M13), Saturn, Mars, Jupiter, Comet Atlas C/2019 Y4, Comet NEOWISE, California Nebula, Bubble Nebula, Flaming Star Nebula widefield, Iris Nebula, Moon with Mars nearby, M81 Bode’s Galaxy & M82 Cigar Galaxy 6-hour exposure.
      • He is fascinated by the history of photography being used for astronomy
      • Instagram page
      • Photo gallery
    • Joe Carr – Southern Sky Celestial Objects
      • Observing and photographing celestial objects from the southern hemisphere
      • How far south to go: Costa Rica, Atacama Desert in Chile, Namibia or Botswana in southern Africa, Australia, New Zealand
      • Photo show: Small and Large Magellanic Cloud galaxies, 47 Tucanae and Omega Centauri globular clusters, Tarantula Nebula, Jewel Box open cluster, Crux and Carina constellations, Eta Carinae Nebula
      • Southern Sky time lapse video from Atacama Lodge, San Pedro de Atacama by Jerry Black
      • Advice on observing and photographing from the souther hemisphere – some challenges for “northerners”.
    • Alec Lee
    • Brock Johnston
    • John McDonald
      • Reprocessing previous astrophotos
      • Milky Way from Cave Creek in the mountains of southern Arizona
      • Witch Head Nebula
      • Closeup of the Moon – Gassendi Crater from the Victoria Centre
      • Uranus and Neptune
      • Photo gallery
  • Lauri Roche
    • RASC 2022 Calendars – signup for a copy – contact Lauri
    • RASC workbooks and almanacs also available
    • Native skywatcher planispheres
    • FDAO Star Party last Saturday – thanks to our members who helped
    • James Web Star Party 2 on Dec 18th – Dr. Madeline Marshall, Dr. Wes Fraser
  • Alberta Astrophotos – Dave Robinson
    • Lunar Eclipse series – Alistair Ling
  • Chris Gainor
    • James Web Space Telescope – launch delayed until Dec 22nd
    • Restoring Hubble Space Telescope to full operation – another instrument is working
  • Lunar Sketch – Randy Enkin
    • Presenting to Nanaimo Astronomy Group this Thursday
    • A new sketch of Petavius and other nearby craters on the terminator of a Waning Gibbous phase

President’s Message – Nov 2021

Posted by as President's Message

Everybody should have a good astro-project on the go. My current one concerns the timing of lunar eclipses.

Solar eclipse geography and timing is known with remarkable precision. So much so that people, including many members of our RASC community, are willing to plan long, difficult, and expensive trips to watch them. The timing and location of the earth’s shadow, or umbra, across the Moon during a lunar eclipse is much more variable and poorly understood.

I was delighted to learn that as far back as 1687, Philippe de la Hire published that the Earth’s shadow was larger than could be accounted for by an airless Earth, leading to lunar eclipses that start a few minutes earlier and end a few minutes later than expected. This was important work, because observing the timing of eclipses was, in principle, one way to measure longitude – as long as the expected timing was well established.

Moon on Dallas Road, Oct 8, 2021, by Randy Enkin

The problem arises from the complex nature of the earth’s atmosphere that obscures, diffracts and refracts the sun’s light on its way to the Moon. I first became aware of the role of amateur lunar crater eclipse timing just before the eclipse last May (which was clouded out), and I am certainly keen to try again on the upcoming lunar eclipse, starting around 23:19 PST on Thursday, November 18. If there are clear skies, I’ll be out with my telescope, noting the time to the tenth of a minute that the earth’s umbra darkens (“immersion”) and then departs (“emersion”) from various lunar craters. Sky and Telescope has been compiling these observations since 1956. Herald and Sinnott (2014) have analysed the compilation, extended back to 1842, with an amazing 22 539 observations. Their main conclusion is that the Earth is surrounded by a “notional eclipse-forming layer” that is 87km thick. It is a really surprising result, since even noctilucent clouds don’t show up that high in the atmosphere.

Herald and Sinnott point out that amateur uninstrumented observations provide continuity with the early observations in their compilation and provide insight into the visual response of the human eye. To help with the observations, Thursday- Friday November 18-19, I have annotated a picture of the full moon with the crater timings predicted by Fred Espenak. I hope some of you will join me making these simple but useful observations.

Look Up,
Randy Enkin, President@Victoria.RASC.ca