The Hubble Ultra Deep Field Image (see description on the right, below)

The Hubble Ultra Deep Field Image
(10,000 galaxies in an area 1% of the apparent size of the moon -- see description on the right, below)

Friday, January 18, 2019

2019 January


AEA Astronomy Club Newsletter January 2019

Contents

AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 1
Astronomy News p. 5
General Calendar p. 11
    Colloquia, lectures, mtgs. p. 11
    Observing p. 14
Useful Links p. 15
About the Club p. 16

Club News & Calendar.

Club Calendar

Club Meeting Schedule:

3 Jan
AEA Astronomy Club Meeting
Pizza party & Astronomy lecture
(A1/1735)




AEA Astronomy Club meetings are now on 1st  Thursdays at 11:45 am.  For 2018:  Jan. 4 in A1/1029 A/B, Feb. 1 & March 1 in A1/2906 and for the rest of 2018 (April-Dec), the meeting room is A1/1735. 

Club News:  

Still waiting to hear if we will get our  FY19 AEA budget request, including software for our new laptop (Starry Night Pro Plus 7 & Maxim DL Pro Suite), a new portable GoTo MCT (Meade ETX-90), an Android tablet & Sky Safari 5 Pro app, SkyFi III wireless scope controller, another Mt. Wilson night, quarterly pizza parties, Astronomical League group membership & Observer’s Handbook.

We need volunteers to help with: 

·         Populating our club Sharepoint site with material & links to the club’s Aerowiki & Aerolink materials
·         Arranging future club programs
·         Managing club equipment

Astronomy Video(s) & Picture(s) of the Month
(from Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html


VIDEO:  Earthrise: A Video Reconstruction 
Explanation: About 12 seconds into this video, something unusual happens. The Earth begins to rise. Never seen by humans before, the rise of the Earth over the limb of the Moon occurred 50 years ago tomorrow and surprised and amazed the crew of Apollo 8. The crew immediately scrambled to take still images of the stunning vista caused by Apollo 8's orbit around the Moon. The featured video is a modern reconstruction of the event as it would have looked were it recorded with a modern movie camera. The colorful orb of our Earth stood out as a familiar icon risingabove a distant and unfamiliar moonscape, the whole scene the conceptual reverse of a more familiar moonrise as seen from Earth. To many, the scene also spoke about the unity of humanity: that big blue marble -- that's us -- we all live there. The two-minute video is not time-lapse -- this is the real speed of the Earth rising through the windows of Apollo 8. Seven months and three missions later, Apollo 11 astronauts would not only circle Earth's moon, but land on it.


VIDEO: Spiraling Supermassive Black Holes https://apod.nasa.gov/apod/ap181203.html
Video Credit: NASA's Goddard Space Flight CenterMusic: In the Hall of the Mountain King by Edvard Grieg
Explanation: Do black holes glow when they collide? When merging, co-orbiting black holes are sure to emit a burst of unusual gravitational radiation, but will they emit light, well before that, if they are surrounded by gas? To help find out, astrophysicists created a sophisticated computersimulation. The simulation and featured resulting video accurately depicts two spiraling supermassive black holes, including the effects of Einstein's general relativity on the surrounding gas and light. The video first shows the system from the top, and later from the side where unusualgravitational lens distortions are more prominent. Numerical results indicate that gravitational and magnetic forces should energize the gas to emit high-energy light from the ultraviolet to the X-ray. The emission of such light may enable humanity to detect and study supermassive black hole pairs well before they spiral together.

VIDEO: Tiny Planet Timelapse  https://apod.nasa.gov/apod/ap181208.html
Video Credit & CopyrightBrian Haidet - Music Credit: Space Walk - Silent Partner
Explanation: You can pack a lot of sky watching into 30 seconds on this tiny planet. Of course, the full spherical image timelapse video was recorded on planet Earth, from Grande Pines Observatory outside Pinehurst, North Carolina. It was shot in early September with a single camera and circular fisheye lens, digitally combining one 24-hour period with camera and lens pointed up with one taken with camera and lens pointed down. The resulting image data is processed and projected onto a flat frame centered on the nadir, the point directly below the camera. Watch as clouds pass, shadows creep, and the sky cycles from day to night when stars swirl around the horizon. Keep watching, though. In a second sequence the projected center is the south celestial pole, planet Earth's axis of rotation below the tiny planet horizon. Holding the stars fixed, the horizon itself rotates as the tiny planet swings around the frame, hiding half the sky through day and night.



Ultima and Thule 
Image Credit: NASAJohns Hopkins University APLSouthwest Research Institute
Explanation: On January 1 New Horizons encountered the Kuiper Belt object nicknamed Ultima Thule. Some 6.5 billion kilometers from the Sun, Ultima Thule is the most distant world ever explored by a spacecraft from Earth. This historic image, the highest resolution image released so far, was made at a range of about 28,000 kilometers only 30 minutes before the New Horizons closest approach. Likely the result of a gentle collision shortly after the birth of the Solar System, Ultima Thule is revealed to be a contact binary, two connected sphere-like shapes held in contact by mutual gravity. Dubbed separately by the science team Ultima and Thule, the larger lobe Ultima is about 19 kilometers in diameter. Smaller Thule is 14 kilometers across.




Sound and Light Captured by Mars InSight 
Image Credit: NASA/JPL-Caltech
Explanation: Your arm on Mars has unusual powers. For one thing it is nearly 2 meters long, has a scoop and grapple built into its hand, and has a camera built into its forearm. For another, it will soon deploy your ear -- a sensitive seismometer that will listen for distant rumblings -- onto the surface of Mars. Your SEISmomet-ear is the orange box in the foreground, while the gray dome behind it will be its protective cover. Your arm is attached to the InSight robotic lander that touched down on Mars two weeks ago. Somewhat unexpectedly, your ear has already heard something -- slight vibrations caused by the Martian wind flowing over the solar panels. Light from the Sun is being collected by the solar panels, part of one being visible on the far right. Actually, at the present time, you have two arms operating on Mars, but they are separated by about 600 kilometers. That's because your other active arm is connected to the Curiosity rover exploring a distant crater. Taken a week ago, rusty soil and rocks are visible in the featured image beyond Insight, as well as the orange sky of Mars.


A Rainbow Geminid Meteor 
Image Credit & Copyright: Dean Rowe
Explanation: Meteors can be colorful. While the human eye usually cannot discern many colors, cameras often can. Pictured is a Geminid captured by camera during last week's meteor shower that was not only impressively bright, but colorful. The radiant grit cast off by asteroid 3200 Phaethon blazed a path across Earth's atmosphere longer than 60 times the angular diameter of the Moon. Colors in meteors usually originate from ionized elements released as the meteor disintegrates, with blue-green typically originating from magnesiumcalcium radiating violet, and nickelglowing green. Red, however, typically originates from energized nitrogen and oxygen in the Earth's atmosphere. This bright meteoric fireball was gone in a flash -- less than a second -- but it left a wind-blown ionization trail that remained visible for several minutes, the start of which can be seen here.

Astronomy News:

Our universe: An expanding bubble in an extra dimension

Date: December 28, 2018
Source: Uppsala University
Summary: Researchers have devised a new model for the universe -- one that may solve the enigma of dark energy. Their new article proposes a new structural concept, including dark energy, for a universe that rides on an expanding bubble in an additional dimension.
FULL STORY


I

n their article, the scientists propose a new model with dark energy and our Universe riding on an expanding bubble in an extra dimension. The whole Universe is accommodated on the edge of this expanding bubble.
Credit: Suvendu Giri
Uppsala University researchers have devised a new model for the Universe -- one that may solve the enigma of dark energy. Their new article, published in Physical Review Letters, proposes a new structural concept, including dark energy, for a universe that rides on an expanding bubble in an additional dimension.
We have known for the past 20 years that the Universe is expanding at an ever accelerating rate. The explanation is the "dark energy" that permeates it throughout, pushing it to expand. Understanding the nature of this dark energy is one of the paramount enigmas of fundamental physics.
It has long been hoped that string theory will provide the answer. According to string theory, all matter consists of tiny, vibrating "stringlike" entities. The theory also requires there to be more spatial dimensions than the three that are already part of everyday knowledge. For 15 years, there have been models in string theory that have been thought to give rise to dark energy. However, these have come in for increasingly harsh criticism, and several researchers are now asserting that none of the models proposed to date are workable.
In their article, the scientists propose a new model with dark energy and our Universe riding on an expanding bubble in an extra dimension. The whole Universe is accommodated on the edge of this expanding bubble. All existing matter in the Universe corresponds to the ends of strings that extend out into the extra dimension. The researchers also show that expanding bubbles of this kind can come into existence within the framework of string theory. It is conceivable that there are more bubbles than ours, corresponding to other universes.
The Uppsala scientists' model provides a new, different picture of the creation and future fate of the Universe, while it may also pave the way for methods of testing string theory.


Story Source:
Materials provided by Uppsala University. Note: Content may be edited for style and length.


Journal Reference:
1.       Souvik Banerjee, Ulf Danielsson, Giuseppe Dibitetto, Suvendu Giri, Marjorie Schillo. Emergent de Sitter Cosmology from Decaying Anti–de Sitter Space. Physical Review Letters, 2018; 121 (26) DOI: 10.1103/PhysRevLett.121.261301

Beyond the black hole singularity

Date:
December 20, 2018
Source:
Penn State
Summary:
Our first glimpses into the physics that exist near the center of a black hole are being made possible using 'loop quantum gravity'-- a theory that uses quantum mechanics to extend gravitational physics beyond Einstein's theory of general relativity.
Share:
FULL STORY


Our first glimpses into the physics that exist near the center of a black hole are being made possible using "loop quantum gravity" -- a theory that uses quantum mechanics to extend gravitational physics beyond Einstein's theory of general relativity. Loop quantum gravity, originated at Penn State and subsequently developed by a large number of scientists worldwide, is opening up a new paradigm in modern physics. The theory has emerged as a leading candidate to analyze extreme cosmological and astrophysical phenomena in parts of the universe, like black holes, where the equations of general relativity cease to be useful.
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Previous work in loop quantum gravity that was highly influential in the field analyzed the quantum nature of the Big Bang, and now two new papers by Abhay Ashtekar and Javier Olmedo at Penn State and Parampreet Singh at Louisiana State University extend those results to black hole interiors. The papers appear as "Editors' suggestions" in the journals Physical Review Letters and Physical Review on December 10, 2018 and were also highlighted in a Viewpoint article in the journal Physics.

"The best theory of gravity that we have today is general relativity, but it has limitations," said Ashtekar, Evan Pugh Professor of Physics, holder of the Eberly Family Chair in Physics, and director of the Penn State Institute for Gravitation and the Cosmos. "For example, general relativity predicts that there are places in the universe where gravity becomes infinite and space-time simply ends. We refer to these places as 'singularities.' But even Einstein agreed that this limitation of general relativity results from the fact that it ignores quantum mechanics."

At the center of a black hole the gravity is so strong that, according to general relativity, space-time becomes so extremely curved that ultimately the curvature becomes infinite. This results in space-time having a jagged edge, beyond which physics no longer exists -- the singularity. Another example of a singularity is the Big Bang. Asking what happened before the Big Bang is a meaningless question in general relativity, because space-time ends, and there is no before. But modifications to Einstein's equations that incorporated quantum mechanics through loop quantum gravity allowed researchers to extend physics beyond the Big Bang and make new predictions. The two recent papers have accomplished the same thing for the black hole singularity.

"The basis of loop quantum gravity is Einstein's discovery that the geometry of space-time is not just a stage on which cosmological events are acted out, but it is itself a physical entity that can be bent," said Ashtekar. "As a physical entity the geometry of space-time is made up of some fundamental units, just as matter is made up of atoms. These units of geometry -- called 'quantum excitations' -- are orders of magnitude smaller than we can detect with today's technology, but we have precise quantum equations that predict their behavior, and one of the best places to look for their effects is at the center of a black hole." According to general relativity, at the center of a black hole gravity becomes infinite so everything that goes in, including the information needed for physical calculations, is lost. This leads to the celebrated 'information paradox' that theoretical physicists have been grappling with for over 40 years. However, the quantum corrections of loop quantum gravity allow for a repulsive force that can overwhelm even the strongest pull of classical gravity and therefore physics can continue to exist. This opens an avenue to show in detail that there is no loss of information at the center of a blackhole, which the researchers are now pursuing.

Interestingly, even though loop quantum gravity continues to work where general relativity breaks down -- black hole singularities, the Big Bang -- its predictions match those of general relativity quite precisely under less extreme circumstances away from the singularity. "It is highly non-trivial to achieve both," said Singh, associate professor of physics at Louisiana State. "Indeed, a number of investigators have explored the quantum nature of the black hole singularity over the past decade, but either the singularity prevailed or the mechanisms that resolved it unleashed unnatural effects. Our new work is free of all such limitations."

Story Source:
Materials provided by Penn State. Original written by Sam Sholtis. Note: Content may be edited for style and length.


Journal Reference:
1.       Abhay Ashtekar, Javier Olmedo, Parampreet Singh. Quantum Transfiguration of Kruskal Black Holes. Physical Review Letters, 2018; 121 (24) DOI: 10.1103/PhysRevLett.121.241301

Cite This Page:
Penn State. "Beyond the black hole singularity." ScienceDaily. ScienceDaily, 20 December 2018. <www.sciencedaily.com/releases/2018/12/181220111804.htm>.


Baby star's fiery tantrum could create the building blocks of planets

Date: December 21, 2018
Source: University of Warwick
Summary: A massive stellar flare on a baby star has been spotted by astronomers, shedding light on the origins of potentially habitable exoplanets.

FULL STORY



Artist’s impression of a similar solar flare (a very large flare from EV Lac) available via the NASA website, use only with Image
Credit: Casey Reed/NASA
A massive stellar flare on a baby star has been spotted by University of Warwick astronomers, shedding light on the origins of potentially habitable exoplanets.
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One of the largest ever seen on a star of its type, the huge explosion of energy and plasma is around 10,000 times bigger than the largest solar flare ever recorded from our own Sun.

The discovery is detailed in a paper for the Monthly Notices of the Royal Astronomical Society and reveals how this huge 'tantrum' could even perturb the material orbiting a star which would create the building blocks for future planets.

The flare was seen on a young M-type star named NGTS J121939.5-355557, located 685 light years away. At around 2 million years old, it is what astronomers refer to as a pre-main sequence star which is yet to reach the size that it spends the majority of its lifecycle.

It was observed as part of a large flare survey of thousands of stars by University of Warwick PhD student James Jackman, as part of a project searching for explosive phenomena on stars outside our solar system. He used the Warwick-led Next-Generation Transit Survey (NGTS) telescope array in Chile which is designed to find exoplanets by collecting brightness measurements of hundreds of thousands of stars and is based at the European Southern Observatory's Paranal Observatory. His attention was drawn to NGTS J121939.5-355557 as it had one of the largest flares seen in these types of stars.

A stellar flare occurs when the magnetic field of a star rearranges itself, releasing huge amounts of energy in the process. This accelerates charged particles, or plasma, within the star which crash into its surface, heating it up to around 10,000 degrees. That energy produces optical and infra-red light, but also x-rays and gamma rays that can be picked up by telescopes on Earth and in orbit.

Magnetic fields on M stars are a lot stronger than those on our own sun and the astronomers calculated that this size of flare is a rare event, occurring anywhere from every three years to twice a decade.

James, who is studying in the University of Warwick's Department of Physics, said: "This is normally a star that shows little activity and stays a constant brightness. Then, on this one particular night, we saw it suddenly grow seven times brighter than normal for a few hours, which is pretty extreme. And then after that it goes back to normal.

"We see these types of flares on the Sun, but no-where near as big as this. On our Sun, you can do incredibly detailed studies on this kind of activity. It's difficult to extend that understanding to other stars because the data we need hasn't been available until now.

"This is an incredibly young star, only about 2 million years old. You'd call it a baby -- it's going to live for ten of billions of years, so it's in the first one percent of its lifetime. Even though it's much cooler than our Sun by about 2000 degrees it is roughly the same size, but pretty large for an M star. This is because it's still being formed from gas in the disc and contracting and cooling until it reaches the main sequence, staying at a certain radius and luminosity for billions of years.

"Finding out these kinds of details has only been possible thanks to the Gaia mission that began earlier this year."
The X-rays from these large flare events are thought to affect the formation of 'chondrules', flash-melted calcium-aluminium-rich grains in the star's protoplanetary disc. These gather together into asteroids that eventually coalesce into orbiting planets. The study adds to our understanding of how flares 'perturb' the protoplanetary disc, moving around the material that impacts on planet formation and affecting the eventual structure of a planetary system.
Professor Peter Wheatley, James's PhD supervisor, said: "A massive flare like this could be advantageous for planet formation, or it could be disruptive. This particular star won't have formed its planets yet so this type of flare activity is something that astronomers will need to take into account when considering planet formation.
"There's a discussion at the moment around whether flares are a good or bad thing for life on orbiting habitable planets, because they output a large amount of UV radiation. That could cause biological damage to surface organisms and damaging their DNA. On the other hand, UV radiation is required for various chemical reactions to start life and that's not typically provided in great enough quantity by these types of stars. These flares could potentially kickstart these reactions." 




Story Source:
Materials provided by University of Warwick. Note: Content may be edited for style and length.


Journal Reference:
1.       James A G Jackman, Peter J Wheatley, Chloe E Pugh, Dmitrii Y Kolotkov, Anne-Marie Broomhall, Grant M Kennedy, Simon J Murphy, Roberto Raddi, Matthew R Burleigh, Sarah L Casewell, Philipp Eigmüller, Edward Gillen, Maximilian N Günther, James S Jenkins, Tom Louden, James McCormac, Liam Raynard, Katja Poppenhaeger, Stéphane Udry, Christopher A Watson, Richard G West. Detection of a giant flare displaying quasi-periodic pulsations from a pre-main-sequence M star by the Next Generation Transit Survey. Monthly Notices of the Royal Astronomical Society, 2019; 482 (4): 5553 DOI: 10.1093/mnras/sty3036


Cite This Page:
University of Warwick. "Baby star's fiery tantrum could create the building blocks of planets." ScienceDaily. ScienceDaily, 21 December 2018. <www.sciencedaily.com/releases/2018/12/181221123729.htm>.



 General Calendar:

Colloquia, Lectures, Seminars, Meetings, Open Houses & Tours:


Colloquia:  Carnegie (Tues. 4pm), UCLA, Caltech (Wed. 4pm), IPAC (Wed. 12:15pm) & other Pasadena (daily 12-4pm):  http://obs.carnegiescience.edu/seminars/ 
Carnegie astronomy lectures – only 4 per year in the Spring www.obs.carnegiescience.edu.  Visit www.huntington.org for directions.  For more information about the Carnegie Observatories or this lecture series, please contact Reed Haynie.  Click here for more information.
3 Jan
AEA Astronomy Club Meeting
Pizza party & Astronomy lecture
(A1/1735)





11 Jan
Friday Night 7:30PM SBAS  Monthly General Meeting
in the Planetarium at El Camino College (16007 Crenshaw Bl. In Torrance)
Topic: “TBA” David Nakamoto


None in Jan.
LAAS General Mtg. 7:30pm Griffith Observatory

Jan. 10 & 11 (none in Dec.) The von Kármán Lecture Series: 2019

Red Planet Rovers and Insights


Get the scoop on the latest missions at Mars. This lecture will bring you up to speed on all things Mars, including: The biggest dust storm in a decade, rolling (and drilling) on "Rubin Ridge," a new rover under construction, and a recent arrival on Mars preparing to get down to business.
Speaker:
Speakers: To be announced

Location:
Thursday, January 10, 2019, 7pm
The von Kármán Auditorium at JPL
4800 Oak Grove Drive
Pasadena, CA
› Directions

Friday, January 11, 2019, 7pm
Caltech’s Ramo Auditorium
1200 E California Blvd.
Pasadena, CA
› Directions

Webcast:
Thursday’s lecture will be shown live on 
Ustream and YouTube








20 Jan.

KY HUGHSON

THE DAWN SPACECRAFT AT CERES, THE LARGEST ASTEROID

Location: Geology 3656
Time: 2:30PM
Ceres has the largest water content among large asteroids. After orbiting asteroid Vesta for 14 months, the Dawn spacecraft used its solar-electric propulsion system to move to Ceres and orbit it. During three years at Ceres, Dawn observed anomalous ammonium, vexatious volcanoes, wandering water ice, freaky flows, effervescent evaporites, capricious carbon, and many more peculiarities. Ceres’ properties suggest that it is an evolved CM chondrite.

7 Feb.
AEA Astronomy Club Meeting
TBD
(A1/1735)

Observing:

The following data are from the 2018 Observer’s Handbook, and Sky & Telescope’s 2018 Skygazer’s Almanac & monthly Sky at a Glance.

Current sun & moon rise/set/phase data for L.A.:  http://www.timeanddate.com/astronomy/usa/los-angeles

Sun, Moon & Planets for January:

  

Moon: Jan 5 new, Jan 13 1st quarter, Jan 20 Full, Jan 27 last quarter,                  
Planets: Venus visible at dawn all month.  Mars visible at dusk, sets before midnight.  Mercury visible at dawn thru Jan. 3.  Saturn visible at dawn after the 23rd. Jupiter visible at dawn all month.
Other Events:

1 January New Horizons Ultima Thule (KBO 2014 MU69) Flyby

3 January Change’e 4 Moon Landing The first attempt to land on the far side of the moon.

3 January Quadrantids Meteor Shower Peak The Quadrantids are a January meteor shower. The Zenithal Hourly Rate (ZHR) of this shower can be as high as that of two other reliably rich meteor showers (120/hour), the Perseids in August and the Geminids in December, yet Quadrantid meteors are not seen as often as meteors in these other two showers, because the peak intensity is exceedingly sharp, sometimes lasting only hours. Additionally, the meteors are quite faint (mean magnitude 3-6 mag).

5 Jan
SBAS out-of-town Dark Sky observing – contact Greg Benecke to coordinate a location. http://www.sbastro.net/.  

6 January Venus at Greatest Western Elongation

5 Jan
LAAS Private dark sky  Star Party

2,9,16,23,30 Jan
LAAS The Garvey Ranch Observatory is open to the public every Wednesday evening from 7:30 PM to 10 PM. Go into the dome to use the 8 Inch Refractor or observe through one of our telescopes on the lawn. Visit our workshop to learn how you can build your own telescope, grind your own mirror, or sign up for our free seasonal astronomy classes.

Call 213-673-7355 for further information.
Time: 7:30 PM - 10:00 PM
Location: Garvey Ranch Obs. , 781 Orange Ave., Monterey Park, CA 91755

12 Jan
LAAS Public  Star Party: Griffith Observatory Grounds 2-10pm

20 January Sunday, 7 PM CalTech Astro: Stargazing and Lecture Series Special Event: Lunar Eclipse and Lecture – Into the Age of Gravitational Wave Astronomy by Jameson Rollins These are free lectures at a public level followed by guided stargazing with telescopes (weather permitting). All events are held at the Cahill Center for Astronomy and Astrophysics at Caltech. No reservations are needed. Lectures are 30 minutes, stargazing lasts 90 minutes. Stay only as long as you want. For directions, weather updates, and more information, please visit: http://outreach.astro.caltech.edu 15

20 January Full/Supermoon and Total Lunar Eclipse Partial phase begins 7:34 pm PST, ends 10:51pm PST. Totality 8:41 pm PST to 9:44 pm PST.


Internet Links:

Telescope, Binocular & Accessory Buying Guides


General


Regional (Southern California, Washington, D.C. & Colorado)


About the Club

Club Websites:  Internal (Aerospace): https://aeropedia.aero.org/aeropedia/index.php/Astronomy_Club  It is updated to reflect this newsletter, in addition to a listing of past club mtg. presentations, astronomy news, photos & events from prior newsletters, club equipment, membership & constitution.  We have linked some presentation materials from past mtgs.  Our club newsletters are also being posted to an external blog, “An Astronomical View” http://astronomicalview.blogspot.com/. 
 
Membership.  For information, current dues & application, contact Alan Olson, or see the club website (or Aerolink folder) where a form is also available (go to the membership link/folder & look at the bottom).  Benefits will include use of club telescope(s) & library/software, membership in The Astronomical League, discounts on Sky & Telescope magazine and Observer’s Handbook, field trips, great programs, having a say in club activities, acquisitions & elections, etc.

Committee Suggestions & Volunteers.  Feel free to contact:  Mark Clayson, President & Program Committee Chairman, Walt Sturrock, VP, TBD Activities Committee Chairman (& club Secretary), or Alan Olson, Resource Committee Chairman (over equipment & library, and club Treasurer).

Mark Clayson,
AEA Astronomy Club President


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