ONLINE – General Meeting – January 2021

TAAA’s first Friday monthly meeting will be held online. The meeting will have a 6:30 P.M. Main Presentation open to the General Public. This will be followed, at approximately 7:15 P.M., by a Members-only meeting, which will feature our popular Seasonal Night Sky Presentation by Mary Turner. We’ll also have voting on proposed Constitution and Bylaw changes. To view the next meeting, please visit https://www.facebook.com/TucsonAstronomy

6:30 pm – Main Public Presentation

Title: Volcanism and Cyrovolcanism in the Solar System: Examples from Earth, Mars, and Europa

Speaker Bio: Joana Voigt received a B.S. and M.S. in Geological Sciences from the Free University Berlin, Germany in 2015 and 2017 respectively and an M.S. in Planetary Sciences from the University of Arizona in 2020. She is currently a Ph.D. candidate at UA’s Lunar and Planetary Laboratory. A planetary geologist, she is primarily interested the eruption products on Earth, Mars, the Moon, to better understand the thermal dynamic evolution of planetary bodies.

Volcanism includes eruptions of silicate magma on terrestrial bodies, as well as in cryovolcanic (icy volcanic) deposts, which form on exceptionally cold outer solar system regions, where water can behave like magma. In Voigt’s presentation, she will discuss examples of silicate volcanism on Earth and Mars, and evidence of cryovolcanism on Jupiter’s moon Europa.

The 2014–2015 Holuhraun eruption produced the largest lava flow-field in Iceland in over two centuries. This eruption helps us understand the dynamics of large silicate lava flows on Earth and on other planetary bodies. Voigt will discuss the Icelandic Holuhraun eruption, and evidence of similar, geologically recent eruptions on Mars that suggest it may still be a volcanically active world. Voigt will also discuss the remains of a cryovolcanic eruption on Jupiter’s moon Europa. She will explain how an impact-induced melting of its crust can generate small brine pockets that lead to a cryovolcanic eruption of salty water onto the surface. Such an eruption—triggered by an impact, not a deep interior process—is fundamentally different from traditional forms of silicate volcanism.

7:15 pm (Approx) – Members-Only Meeting

Title: Seasonal Night Sky followed by voting on Constitution and Bylaw changes

Speaker: Mary Turner

The main presentation will be followed by a Members-only meeting, which features our popular Seasonal Night Sky presentation by Mary Turner. We’ll also have voting on proposed Constitution and Bylaw changes

MEMBERS SHOULD MAKE SURE TO USE THE ZOOM LINK, IN ORDER TO BE INCLUDED.

Virtual Jupiter/Saturn Conjunction Stream

Join the Tucson Amateur Astronomy Association for a live telescope stream of the Jupiter/Saturn Conjunction. This is a once (or twice if you are young) in a lifetime event. The planets will get to within .1 degree on December 21st. They are actually separated by distance as Jupiter is 551 million miles from Earth and Saturn is about twice as far at just over 1 billion miles from Earth. They will be close enough to be a challenge to separate with just your eyes. Observing with a pair of binoculars or a telescope is ideal. The last time they were this close together and were observable was in 1226 (794 years ago). The next conjunction that will be this close will be in 2080. The pair starts December about 2 degrees apart. The distance decreases by about .1 degree every day, so observe them every evening and watch them get closer to each other. On the 21st, join us to view them through a refractor telescope.

The Conjunction will be streamed live to our Facebook Page: https://www.facebook.com/TucsonAstronomy

32 inch Cassegrain Project

Planets of the Month: DECEMBER

by Erich Karkoschka

RARE CONJUNCTION ALERT!!

Jupiter and Saturn will get as close as .1 (1/10 of a degree) from each other on December 21st (Winter Solstice) — they are actually separated by distance as Jupiter is 551 million miles from Earth and Saturn is abut twice as far at just over 1 Billion miles from Earth . That will be close enough to challenge being able to separate both with just your eyes. If you get a chance, observe them with your eyes, a pair of binoculars, or a telescope (great opportunity to compare both planets at high power in the same field of view). For comparison, the width of your clenched fist held at arms length is about 10 degrees. On the 21st, they set pretty shortly after sunset, so go out about 1/2 hour after sunset to view them (they will set around 7 pm). The last time they got this close together and were both observable was 1226 (794 years ago). The next conjunction that will be this close will be in 2080. The pair starts December about 2 degrees apart. The distance decreases by about .1 degree every day, so observe them every evening and watch them get closer to each other. Look for a small crescent Moon near the pair on the 16th (5 degrees below) & the 17th (10 degrees to the left).

Venus rises after 5 am and is still conspicuous during dawn. Venus will be only be 1/6 of a degree from a second magnitude star (Acrab) on the morning of the 18th. This is too close to see next to bright Venus with the naked eyes, but a splendid view in binoculars.

Mars fades quickly this month, but is still the brightest object aside from Jupiter and Sirius after it rises late evening. Its diameter of 14 arc-seconds is still larger than its opposition diameter during less favorable oppositions, such as in 2027.

Uranus is 20 degrees to the upper left of Mars at the beginning of December. It can be easily seen in binoculars but requires some practice to find it. By the end of the year, the separation to Mars is only 10 degrees.

Neptune is well to the lower right of Mars, best observable right after dusk.

On the morning of December 12th, the thin lunar crescent will be only 3 degrees from Venus, most spectacular between 5:30 and 6 am. Very experienced observers may try to find them in the afternoon when the moon will occult Venus at around 2:20 pm. They will be only about 15 degrees high. The moon will definitely not be visible naked eye because it is too slim, but the view in a telescope would be good with the disappearance of Venus taking half a minute.

On the 14th, part of Chile and Argentina will experience a total solar eclipse. Some of us had plans to observe it, but had to cancel because of travel restrictions. Instead, we can watch the Geminid meteor show the evening before without moonlight and a peak predicted to occur during that evening, the 13th. Best viewing though is the early morning hours of December 14th.

General Astronomy, Solar System

Planets of the Month: NOVEMBER

by Erich Karkoschka

Brillant Venus outshines all the stars in the morning sky, passing Spica on the 16th. Far below Venus is Mercury, next to Spica on the 2nd. By the 10th at greatest elongation, it is as

easy to see as it can be seen from our latitude. It disappears at the end of the month.

The crescent moon stands between Mercury and Venus on the morning of the 13th, near Jupiter and Saturn on the 18th and 19th, and finally just below Mars on the 25th.

Mars is conspicuous since it is bright orange and high in the sky all evening. It is still 20 arc-sec in diameter so that telescopes show fine detail. However, it is receeding fast. By the end of the
month, it is less than half as bright and only 15 arc-sec in diameter. Nevertheless, this is still better than the maximum in some oppositions.

Minor planet Flora No. 8 can be found with binoculars as magnitude 8 in Cetus, well placed in the evening sky. It is its best showing between 1980 and 2060.

Jupiter and Saturn are well up during the early evening, transiting
just before sunset. Saturn is 5 degrees east of Jupiter during early
November, closing to 2 degrees by the end. We are not far from their closest

conjunction in centuries, on December 21. On the 2nd, a telescope shows Callisto in transit as a dark spot. On the 8th, the dark spot is the shadow of Ganymede, and on the 15th after 7pm, it is Ganymede itself. Finally, on the 19th until 6:40 pm, it is Callisto again.

Uranus and Neptune are also well up in the evening. Neptune transits earlier than Mars. Uranus transits at midnight in early November since it came into opposition October 31st.

Pluto is easy to find on the 14th since it is only 41 arc-min south of Jupiter. But it still is a challenge to identify it among hundreds
of other stars of similar magnitude, 14 mag.

On the morning of the 30th, there will be a penumbral lunar eclipse with a maximum at 2:43 am. Since 85 % of the moon will be inside the penumbra, it will be noticeable with the northern edge significantly darkened.

ONLINE – Astronomy Fundamentals Meeting – December 2020

Constellation of the Month:

None

Presenter: none

We do not have a constellation of the month for this meeting.

Main Presentation:

Open Floor Discussion

Presenter: none

This month, instead of presentations, we will be doing an open floor discussion on topics brought up by attendees.

ONLINE – General Meeting – December 2020

TAAA’s first Friday monthly meeting will be held online. The December meeting will have a 6:30 P.M. Main Presentation open to the General Public. This will be followed at approximately 7:15 P.M. by a Members-only meeting, at which TAAA’s David Rossetter will present proposed Constitution and Bylaw changes. To view the next meeting, please visit https://www.facebook.com/TucsonAstronomy

6:30 pm – Main Presentation

Title: Fun with Fermi AGN – A Quick Stroll Through a Lethal Photon Field

Speaker Bio: Paul Smith was born in Rochester, NY, during the year Sputnik circled the planet, and numerous atmospheric nuclear tests were conducted, as the two dominant global powers rattled sabers. Dr. Smith muses it might have been the high tensions of the era, or the elevated radiation levels that pulled him into science, particularly astronomy, by grade 4. He earned a B.S. in physics from Saint Louis University, and a Ph.D. in the same field from the University of New Mexico, before moving to Tucson in 1986. For most of the past 35 years, Dr. Smith has been at Steward Observatory, and has been successively involved with the Hubble, Spitzer, and Fermi space observatories. His main research interest is the polarized light emitted from quasars and other types of active galactic nuclei (AGN).

Presentation: Dr. Smith’s presentation centers around NASA’s Fermi Gamma-ray Space Telescope and the decade-long effort to support this important science mission by using telescopes in the Tucson area to observe the most active quasars. While extremely active quasars, or blazars, represents a small percentage of the population of known active galactic nuclei (AGN), it makes up over 70% of the objects detected by Fermi in the high-energy gamma-ray sky. Blazars are highly variable in brightness and polarization on short time scales (less than a day), enabling us to study relatively small regions that produce enormous amounts of energy. Many observations at different wavelengths are needed to understand the physics of these systems. Dr. Smith’s presentation will take us to the cutting edge of science.

7:15 pm (Approx) – Second Presentation

Title: Members-only Meeting – Constitution and Bylaw changes

Speaker: David Rossetter

The main presentation will be followed by a members-only meeting, at which David Rossetter will present proposed Constitution and Bylaw changes.

TAAA & LPL Virtual Star Party

Join TAAA and the Lunar and Planetary Laboratory for a Solar System exploration, shared via Webinar: https://www.lpl.arizona.edu/art/2020.

Virtual Solar Observing

We will be doing a Virtual Solar Observing session with the Lunar & Planetary Laboratory. To view the event, register at: https://www.lpl.arizona.edu/art/2020.

ONLINE – Astronomy Fundamentals Meeting – November 2020

Constellation of the Month:

None

Presenter: none

We do not have a constellation of the month for this meeting.

Main Presentation:

Venus

Presenter: Doug Smith

Our only presentation this month will be Doug Smith discussing the planet Venus .

ONLINE – General Meeting – November 2020

TAAA’s first Friday monthly meeting will be held online. The November meeting will have a 6:30 P.M. presentation open to the general public. This will be followed at approximately 7:15 P.M. by a members-only meeting. To view the next meeting, please visit https://www.facebook.com/TucsonAstronomy

6:30 pm – Main Presentation

Title: From Tucson to Tokyo: Building a Global Movement for Dark Sky Protection

Speaker: Ruskin Hartley joined the International Dark-Sky Association in February 2019. He brings 20 years of conservation experience to IDA’s work to protect the night from light pollution. Ruskin’s passion is protecting precious natural resources. He served as Executive Director of Save the Redwoods League, a non-profit dedicated to protecting and restoring the redwood forest; as CEO of Heal the Bay in Los Angeles; and as Vice President of Resource Development at Fair Trade USA. Originally from the United Kingdom, Ruskin holds a bachelor’s degree from the University of Cambridge and a master’s degree from the University of East Anglia. Ruskin loves to head out on the trail with his wife and kids or cook-out under the stars..

On October 23, 1987, two Tucson Doctors—one M.D. and one PH.D.—incorporated the International Dark-Sky Association devoted to the “protection and restoration of dark nighttime skies through application and promotion of proper lighting practices.” What started as an astronomical-driven venture in Tucson is now a broad movement active on all continents. While light pollution has increased in the intervening years, Tucson continues to lead the way and show what is possible. Ruskin will explore emerging themes in dark sky conservation, discuss the global perspective, and share IDA’s strategy for accelerating dark sky protection worldwide.

7:15 pm (Approx) – Second Presentation

Title: Members-only Meeting

Speaker: none

The main presentation will be followed by a members-only meeting.