by Erich Karkoschka
Mercury is easily visible in the first half of the month during dust in the west. It disappears after the 18th.
Venus is 40 degrees high at sunset and even 44 degrees by the end of the month. This is close to the maximum possible. It sets after 9 pm. The Moon will visit Venus on the 27th, a beautiful sight.
MAIN EVENT. Occultation of Mars by the Moon on the morning of February 18, well visible from Tucson before dawn in the southeast. It starts about an hour after Mars rises and lasts for another hour. Mars disappears behind the bright side of the Moon at 4:38 am and will reappear at 5:40 am along the dark side. The disappearance will be visible in binoculars as Mars slowly becomes invisible 
at the bright limb of the Moon. The reappearance will also take about 20 seconds. Since it occurs at the dark limb, it can be observed with the naked eye.
Uranus is 60 degrees high after dusk, visible in binoculars or a telescope.
Morning Sky. Mars rises at 4 am. Jupiter follows at 5 am, and Saturn at 6 am. These three planets will get closer to each other as the month progresses.
Constellation of the Month:
Auriga
Presenter: Gus Gomez
Gus Gomez will be presenting Auriga for the constellation of the month.
Main Presentation:
Discussion on Equipment Modifications
Presenter:
Our main topic will be an open discussion on equipment modifications that members have done to enhance their viewing sessions.
6:30 pm – Introductory Presentation
Title: The Astronomical League and TAAA’s Astronomy Fundamentals Class
Speakers: Doug Smith and JD Metzger
TAAA member Doug Smith talks about The Astronomical League, and TAAA member JD Metzger talks about TAAA’s Astronomy Fundamentals Class.
7:30 pm – Main Presentation
Title: Using Light Echoes as Time Machines
Speaker: Jennifer Andrews is an observational astronomer interested in massive stars and the violent explosions that signal the end of their lives. She has been at Steward Observatory for the past few years, and spends a lot of her time observing supernovae and other transients with telescopes in Southern Arizona. Jennifer received her PhD at Louisiana State University, and prior to moving to Tucson she worked as a postdoc at the University of Massachusetts
The great eruption of the massive star Eta Carinae in the mid-1800s was a spectacular astronomical event, when it likely ejected a mass of material 10 – 20 times that of the Sun, and was visible to the naked eye. Until recently the only observations of that eruption were historical visual estimates of Eta Carinae’s brightness and color. Thanks to our evolving ability to use light echoes (LEs) we can now re-examine the event. As some light from Eta Carinae’s eruption traveled directly toward us and was observed in the 1800s, light directed away from us was scattered off dust, and we are finally observing it today as a light echo. Over the past decade we have been obtaining imaging and spectroscopy of these echoes with telescopes in the Southern Hemisphere, enabling us to reconstruct Eta Carinae’s physical state prior to and during the great eruption. Jennifer will discuss these observations and what they reveal about one of the most enigmatic massive stars in the Milky Way
TAAA Support to the Saguaro National Park EAST monthly astronomy event.
Join park naturalists for an introduction to astronomy and a look at the desert night sky. Telescopes and binoculars will be available. Reservations are required. Call the Visitor Center at (520) 733-5153. Accessible Program.
Observing and talk will be at the Visitor Center from 7 – 9 pm.
TAAA Support to the Saguaro National Park EAST monthly astronomy event.
Join park naturalists for an introduction to astronomy and a look at the desert night sky. Telescopes and binoculars will be available. Reservations are required. Call the Visitor Center at (520) 733-5153. Accessible Program.
Observing and talk will be at the Visitor Center from 7 – 9 pm.
Constellation of the Month:
Auriga
Presenter: Gus Gomez
Gus Gomez will be presenting Auriga for the constellation of the month.
Main Presentation:
Discussion on Equipment Modifications
Presenter:
Our main topic will be an open discussion on equipment modifications that members have done to enhance their viewing sessions.
6:30 pm – Introductory Presentation
Title: Member Planet Database Update
Speaker: David Rosetter
TAAA member, David Rosetter, in charge of the TAAA Member Planet system, (which manages the TAAA member database), will talk about expanded web benefits for TAAA members and provide information on the web options available. Bring any questions you have on how to best access TAAA information.
7:30 pm – Main Presentation
Title: A Tale of Two Galaxies
Speaker: Dr. Knut Olsen is a staff astronomer at the National Science Foundation’s Optical-Infrared Astronomy Research Laboratory, based in Tucson. Born in Norway, he moved to the U.S. at a young age and quickly developed a fascination for astronomy. He worked on the Magellanic Clouds as part of his Ph.D. thesis, and continued his exploration of them while living and working in La Serena, Chile, where the Clouds are naked eye objects. He moved to Tucson in 2007.
Dr. Olsen will present a personal story of how a chance observing run kicked off more than a decade of exploration of and discovery in the Magellanic Clouds, two of our most prominent neighbor galaxies. The Magellanic Clouds have been key to establishing the extragalactic distance scale, played a seminal role in the discovery of Dark Energy, and are causing us to adjust our view of the Milky Way.
by Erich Karkoschka
Planets for December 2019
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Mercury will be visible until December 19th, rising just after Mars (15 degrees below) before dawn. |
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Venus is in the evening sky, getting higher and more obvious. |
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New Moon will be at Christmas, last visible in the morning of the 24th and coming back in the evening sky on the 27th below Venus and the 28th right next to Venus, a beautiful pair. |
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Mars rises before dawn in Libra, followed by Mercury 15 degrees below. |
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Saturn is to the upper left of Venus in the evening sky until December 10 & 11, when Venus passes two degrees south of Saturn. At that time, Pluto is right next to both planets, but 15 million times fainter than Venus and not an easy target. After Christmas, Saturn will be too close to the Sun to be visible. |
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Uranus is well placed in the evening for observers with binoculars or a telescope. |
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Neptune is well placed in the evening for observers with binoculars or a telescope. |
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Pluto is next to Venus & Saturn December 10 & 11 but is 15 million times fianter and not an easy target. The brightest minor planet, Vesta, is not too far from Uranus and only slightly fainter. |
We have two Tucson public observing events this month.
– Agua Caliente Park (NE Tucson) on December 21st: CANCELLED
– Tucson Mountain Park Ironwood Picnic Area (SW Tucson) on December 28 from 6 – 8 pm. Follow the Facebook event for real-time updates.
Meteor Shower. The Geminids peak early morning on December 14th or late evening on the 14th. There will be a bright Moon in the sky very close to Gemini which will limit what you can see. If possible put the Moon to your back and look for meteors in the opposite direction.
