January 11: First meeting of 2021

The first 2021 Membership Meeting of the Cuyahoga Astronomical Association (CAA) will take place Monday, January 11, from 7:30 to 9:00 p.m. via the Zoom online meeting service. The evening’s speaker will be CAA member Matt Franduto who will present, “My 2020 Calendar and the images I took and included or excluded!” Club member Mat Franduto is one of our astrophotographers and every year he produces a calendar based on the astronomical images that he took during the previous year. He will show the pics he included, the ones he excluded, and perhaps a few surprises!

Attendees may join the Zoom meeting beginning at 7:20 p.m. the nights of CAA scheduled meetings and meetings begin at 7:30.

The evening will begin with introductions and the featured speaker followed by the monthly membership business meeting, typically concluding at about 9 PM. Guest attendees are welcome.

To attend:

“Doors open” at 7:20
You can either “Phone in” or watch and participate via “Zoom Video”.

Phone In: Just dial: 1-312-626-6799 (Chicago number)
You will be required to enter our meeting number: 987 496 1637

Or….

Zoom Video with video and audio, on your web browser. (No camera required)
https://csuohio.zoom.us/j/9874961637 (No password to enter)

The Great Conjunction of 2020

On December 21, 2020 Jupiter and Saturn will appear closer in our sky than they have since the year 1623 — only .10º apart. By way of comparison, Earth’s Moon covers about .50º on average! In fact, the two planets will have so little visual separation that they may appear as one bright “star” in our evening sky. As with many objects we see in our night sky, planets Jupiter and Saturn will only appear to be near to each other; they will will be physically separated by about 456 million miles.

The position of the planets as they will be at 7:00 PM EST, December 21, 2020. The bright green line represents the sight line from Earth to Jupiter and Saturn. Image Credit: SkySafari / James Guilford

Here’s why the planets will appear so close in our sky:

Viewed from Earth and looking out toward Jupiter and Saturn we see the planets as if they were in the same orbit — like watching runners in their separate lanes as one overtakes the other. Viewed from “above” we can see that the planets remain well apart.

Viewed closer to the orbital plane of the planets we see how Jupiter and Saturn appear closer together against the background of space. The green line represents the sight line from Earth to the planets. Image Credit: SkySafari / James Guilford

As we drop lower and closer to the orbital plane it becomes more difficult to separate Jupiter and Saturn until, on December 21, 2020, we won’t be able to see them as discrete objects without the use of a telescope!

Jupiter and Saturn appear to merge, on December 21, 2020 as viewed from Earth and depicted here just above the orbital plane of the planets. Image Credit: SkySafari / James Guilford

While the previous extremely close conjunction took place in 1623, Jupiter and Saturn were too close to the Sun to be observed. The last time they could actually be seen so close together was even longer ago: on March 4, 1226. Great Conjunctions take place just short of 20 years apart and most are not so close as this year’s — the next will take place on October 31, 2040, when Jupiter and Saturn will be separated by 1.1º which will be close, but not so amazing as 2020.

Jupiter and Saturn may be seen in the same narrow field of view during 2020’s Great Conjunction. This simulation depicts the position of Jupiter’s Galilean Moons and Saturn’s giant satellite, Titan. Image Credit: SkySafari

If you plan to take a look, you’ll need clear skies (of course!) and you’ll need to be timely — the planetary pair will become visible low in the southwestern sky with the fading twilight and will set in the west by 7:20 PM, December 21. To see the individual planets during their close encounter will require a telescope — a small one will do — or a decent telephoto lens on a camera mounted on a tripod. Given good optics and clear skies, viewers will be able to make out the Galilean Moons of Jupiter and, perhaps spy Titan, Saturn’s brightest moon.

Before and after the 21st, Jupiter and Saturn will appear close together as they first approach, and then recede from the conjunction, continuing to move along their orbital paths. The historic astronomical event will be one night and one night only in our lifetimes. Clear skies, please!

December 14 meeting features talk on cosmology

Glenn StarkmanDecember 14: The December 14 meeting of the Cuyahoga Astronomical Association (CAA) will feature a fascinating talk on cosmology, rounding out this most unusual year for the club. COVID-19 isolation restrictions on group gatherings, and closed meeting facilities caused the club to take its meetings online via the Zoom cloud service. Normally the club hosts a December dinner in lieu of a year-end meeting but since the dinner cannot be held, there will be a December “virtual” meeting complete with speaker.

Professor Glenn Starkman, co-chair of physics and astronomy at Case Western Reserve University will present “The Big Bang and Beyond.” Dr. Starkman will take us to the beginnings of space and time, and show us what we know, what we think we know, and what we wish we knew. Attendees may join the Zoom meeting beginning at 7:20 p.m. the nights of CAA scheduled meetings and meetings begin at 7:30.

The evening will begin with introductions and the featured speaker followed by the monthly membership business meeting, typically concluding at about 9 PM. Guest attendees are welcome.

To attend:

“Doors open” at 7:20
You can either “Phone in” or watch and participate via “Zoom Video”.

Phone In: Just dial: 1-312-626-6799 (Chicago number)
You will be required to enter our meeting number: 987 496 1637

Or….

Zoom Video with video and audio, on your web browser. (No camera required)
https://csuohio.zoom.us/j/9874961637 (No password to enter)

Weak lunar eclipse coming November 30

There will be a lunar eclipse the morning of November 30, 2020 but you may not want to get out of a warm bed to view it — it will be fairly “weak.” This month’s eclipse, viewable in its entirely from Northern Ohio (given clear skies) is of the penumbral variety and will not display the eerie colors that make total lunar eclipses so exciting.

NASA Solar and Earth images, illustration by James Guilford.
A penumbral lunar eclipse occurs when the Moon passes through the thin outer portion of the shadow Earth casts out into space.

A penumbral lunar eclipse occurs when the Full Moon passes through the shady outer circle — the penumbra — of Earth’s shadow streaming out into space. Careful observers will note how most of Moon dims slightly with a sliver of a brighter southern edge and a darker northern area. During a total lunar eclipse, the Full Moon passes fully through the darkest portion of Earth’s shadow, the umbra, and is illuminated by the colors of the globe’s sunrises and sunsets. Again, that won’t happen this time.

Penumbral Lunar Eclipse – November 30, 2020. Credit: F. Espenak, NASA’s GSFC eclipse.gsfc.nasa.gov/eclipse.html

Most of Monday’s event is quite subtle and takes a long time, many won’t even notice the difference. If you want to see this eclipse at its best, even photogenic, view it only around maximum. The penumbral eclipse begins [P1] at 2:32 AM, reaches its Greatest eclipse (you may note northern darkening) at 4:52 AM, and the event ends [P4] at 6:53 AM when Moon completes its emergence from Earth’s shade.

The next total lunar eclipse — the type that features coppery-red colors at its peak — will take place May 26, 2021; unfortunately, that event will reach its maximum as Moon sets locally. The next total lunar eclipse that we might see in its entirety will take place May 16, 2022 and that should be a doozie!