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The Grand Traverse Astronomical Society is a nonprofit organization dedicated to to education and enjoyment of the night sky. Established in 1982, the GTAS has about 30 members from the Traverse City and the Grand Traverse area of northern Michigan. Meetings are held on the first Friday of every month beginning at 8 p.m. at Northwestern Michigan College's Joseph H. Rogers Observatory, though the August meeting is preempted by the annual picnic at another location.

Guests are always welcome to our meetings.

Over 750 attended the society sponsored Comet Hyakutake Watches March 23, and 24th, 1996. The farthest traveler came from Detroit to enjoy the dark skies and the spectacular comet through many telescopes. Comet Hale-Bopp attracted approximately 1,400 during the three scheduled viewing nights that were clear.

We've hit the road, so to speak, with outreach beyond the NMC Observatory since 2007. Since 2011 we've held monthly star parties at Sleeping Bear Dunes National Lakeshore from April to October with additional eclipse and meteor shower watches. We bring our telescopes and exhibits to several festivals around the area along with Friday Night Live in Traverse City. Since 2010 the society has been hosting monthly star parties at the Sleeping Bear Dunes National Lakeshore.

The GTAS belongs to the International Dark-Sky Association and participates in Project Astro.

Two of our members are also NASA/JPL Solar System Ambassadors.

Upcoming Society Events

Friday, December 68 pm, Monthly meeting and star party at NMC Rogers Observatory. Also available via Zoom.

8 pm – General Meeting: My Last Look at the Star of Bethlehem by Bob Moler..

9 pm – Star party if clear.

Zoom Meeting Instructions:

Link: https://us02web.zoom.us/j/8388913229?omn=88435646093

Friday, January 38 pm, Monthly meeting and star party at NMC Rogers Observatory. Also available via Zoom.

8 pm – General Meeting

9 pm – Star party if clear.

Check here often for other events that may pop up during the month.



Star parties at the Sleeping Bear National Lakeshore are expected to resume in late spring 2025.


This article is distributed by NASA Night Sky Network

T he Night Sky Network program supports astronomy clubs across the USA dedicated to astronomy outreach. Visit nightsky.jpl.nasa.gov to find local clubs, events, and more!


December’s Night Sky Notes:
Spot the King of Planets

By Dave Prosper
Updated by Kat Troche

Jupiter is our solar system’s undisputed king of the planets! Jupiter is bright and easy to spot from our vantage point on Earth, helped by its massive size and banded, reflective cloud tops. Jupiter even possesses moons the size of planets: Ganymede, its largest, is bigger than the planet Mercury. What’s more, you can easily observe Jupiter and its moons with a modest instrument, just like Galileo did over 400 years ago.

NASA’s Juno mission captured this look at the southern hemisphere of Jupiter on Feb. 17, 2020, during one of the spacecraft’s close approaches to the giant planet. This high-resolution view is a composite of four images captured by the JunoCam imager and assembled by citizen scientist Kevin M. Gill. Credit: NASA, JPL-Caltech, SwRI, MSSS | Image processing by Kevin M. Gill, © CC BY

Jupiter’s position as our solar system’s largest planet is truly earned; you could fit 11 Earths along Jupiter’s diameter, and in case you were looking to fill up Jupiter with some Earth-size marbles, you would need over 1300 Earths to fill it up – and that would still not be quite enough! However, despite its formidable size, Jupiter’s true rule over the outer solar system comes from its enormous mass. If you took all of the planets in our solar system and put them together, they would still only be half as massive as Jupiter all by itself. Jupiter’s mighty mass has shaped the orbits of countless comets and asteroids. Its gravity can fling these tiny objects towards our inner solar system and also draw them into itself, as famously observed in 1994 when Comet Shoemaker-Levy 9, drawn towards Jupiter in previous orbits, smashed into the gas giant’s atmosphere. Its multiple fragments slammed into Jupiter’s cloud tops with such violence that the fireballs and dark impact spots were not only seen by NASA’s orbiting Galileo probe but also by observers back on Earth!

Look for Jupiter near the Eye of the Bull, Aldebaran, in the Taurus constellation on the evening of December 15, 2024. Binoculars may help you spot Jupiter’s moons as small bright star-like objects on either side of the planet. A small telescope will show them easily, along with Jupiter’s famed cloud bands. How many can you count? Credit: Stellarium Web

Jupiter is easy to observe at night with our unaided eyes, as well-documented by the ancient astronomers who carefully recorded its slow movements from night to night. It can be one of the brightest objects in our nighttime skies, bested only by the Moon, Venus, and occasionally Mars, when the red planet is at opposition. That’s impressive for a planet that, at its closest to Earth, is still over 365 million miles (587 million km) away. It’s even more impressive that the giant world remains very bright to Earthbound observers at its furthest distance: 600 million miles (968 million km)! While the King of Planets has a coterie of 95 known moons, only the four large moons that Galileo originally observed in 1610 – Io, Europa, Ganymede, and Calisto – can be easily observed by Earth-based observers with very modest equipment. These are called, appropriately enough, the Galilean moons. Most telescopes will show the moons as faint star-like objects neatly lined up close to bright Jupiter. Most binoculars will show at least one or two moons orbiting the planet. Small telescopes will show all four of the Galilean moons if they are all visible, but sometimes they can pass behind or in front of Jupiter or even each other. Telescopes will also show details like Jupiter’s cloud bands and, if powerful enough, large storms like its famous Great Red Spot, and the shadows of the Galilean moons passing between the Sun and Jupiter. Sketching the positions of Jupiter’s moons during the course of an evening – and night to night – can be a rewarding project! You can download an activity guide from the Astronomical Society of the Pacific at bit.ly/drawjupitermoons

Now in its eighth year, NASA’s Juno mission is one of just nine spacecraft to have visited this impressive world. Juno entered Jupiter’s orbit in 2016 to begin its initial mission to study this giant world’s mysterious interior. The years have proven Juno’s mission a success, with data from the probe revolutionizing our understanding of this gassy world’s guts. Juno’s mission has since been extended to include the study of its large moons, and since 2021 the plucky probe, increasingly battered by Jupiter’s powerful radiation belts, has made close flybys of the icy moons Ganymede and Europa, along with volcanic Io. What else will we potentially learn in 2030 with the Europa Clipper mission?

Find the latest discoveries from Juno and NASA’s missions to Jupiter at science.nasa.gov/jupiter/

Originally posted by Dave Prosper: February 2023

Last Updated by Kat Troche: November 2024


Links


For Kids: NASA’s Space Place website

The Space Place is a NASA website for elementary school-aged kids, their teachers, and their parents.

  • It’s colorful! It’s dynamic!
    It’s fun!

  • It’s rich with
    Science,
    Technology, Engineering, and
    Math (STEM) content!

  • It’s informal.

  • It’s easy to read and understand.

  • It’s also in Spanish.

  • And it’s free!

It has over 150 separate modules for kids, including hands-on projects, interactive games, animated cartoons, and amazing facts about space and Earth science and technology.



See this month's NASA Night Sky Network article at the bottom of the center panel on this page.



Also check out these two sites for kids: NASA's Climate Kids and NOAA's SciJinks


Bob Moler's Ephemeris contains audio mp3s of current Ephemeris programs; calendars of sunrise, sunset,moonrise and moonset for the Grand Traverse area of Michigan, and other locations in northern Michigan; plus a monthly star chart.

Also Bob's Ephemeris Blog with daily transcripts of and illustrations for his Ephemeris programs on Interlochen Public Radio. Wednesday’s program looks at where the bright planets are along with finder charts.

Northwestern Michigan College's Joseph H. Rogers Observatory


If you'd like to donate

From Article II, B of the Articles of Incorporation of the Grand Traverse Astronomical Society:

The Society shall operate a scientific and educational organization with the goal of increasing interest in, the knowledge and enjoyment of astronomy; cooperate with similar organizations; and cooperate with Northwestern Michigan College to increase the benefit of the college observatory to the community.

As you can see by the statement above the society is inexorably linked to the Joseph H. Rogers observatory. However in the past number of years members have been also taking telescopes out into the community, on sidewalks and street corners, and in the street on Friday Night Live, and to the Sleeping Bear Dunes National Lakeshore. We find that many folks in the area have never been out to the observatory. This way we are going to to the public. And having a huge telescope is really a great attraction, not to mention the superb views of the heavens it will provide.

We have purchased a 25 inch Dobsonian telescope with trailer to use and to take around for our outreach program. We have also purchased two solar telescopes to view the Sun's prominences and chromosphere.

We have recently purchased small telescopes to give to libraries for them to lend out. The first two recipients are Traverse Area District Library and Betsie Valley District Library. Enerdyne of Suttons Bay donated the second telescope..

You may contribute to the fund to help us upgrade and add accessories to the society's telescopes by mailing a check to the GTAS, c/o the society treasurer Gary Carlisle, 1473 Birmley Rd, Traverse City, MI 49686. We are a 501(c)(3) non profit organization. Donations are tax deductible.

Thank You!