Amateur Astronomy Under The Big Sky
RSS icon Email icon Bullet (black)
  • Mercury Transit 2019

    Did you know that there are two other objects in our skies that have phases like the Moon? They’re the inner planets, found between Earth and the Sun: Mercury and Venus. You can see their phases if you observe them through a telescope. Like our Moon, you can’t see the planets in their “new” phase, unless they are lined up perfectly between us Earthlings and the Sun. In the case of the Moon, this alignment results in a solar eclipse; in the case of Mercury and Venus, this results in a transit, where the small disc of the planet travels across the face of the Sun. Skywatchers are in for a treat this month, as Mercury transits the Sun the morning of November 11!

    You may have seen the transit of Venus in 2012; you may have even watched it through eclipse glasses! However, this time you’ll need a solar telescope to see anything, since eclipse glasses will only reveal the Sun’s blank face. Why is that? Mercury is the smallest planet in our solar system, and closer to the Sun (and further away from Earth) during its transit than Venus was in its 2012 transit. This makes Mercury’s disc too small to see without the extra power of a telescope. Make absolutely certain that you view the transit via a telescope equipped with a safe solar filter or projection setup. Do NOT combine binoculars with your eclipse glasses; this will instantly burn a hole through the glasses – and your eyes!

    What a fun opportunity to see another planet during the day! This transit is expected to last over five hours. Folks on the East Coast will be able to watch the entre transit, weather permitting, from approximately 7:35 am EST until around approximately 1:04 pm EST. Folks located in the middle of North America to the west coast will see the transit already in progress at sunrise. The transit takes hours, so if your weather is cloudy, don’t despair; there will be plenty of time for skies to clear! You can find timing details and charts via eclipse guru Fred Espenak’s website:

    Mercury’s orbit is small and swift, and so its position in our skies quickly changes; that’s why it was named after the fleet-footed messenger god of Roman mythology. In fact, if you have a clear view of the eastern horizon, you’ll be able to catch Mercury again this month! Look for it before dawn during the last week of November, just above the eastern horizon and below red Mars. Wake up early the morning of November 24th to see Mars, the Moon, and Mercury form a loose triangle right before sunrise.

    Discover more about Mercury and the rest of our solar system at

    This photo from the same 2016 transit event shows Mercury a bit larger, as it should; it was taken at a higher magnification through a large 16 inch telescope! Credit: J. A. Blackwell

    By David Prosper

  • SMAS September meeting

    Join SMAS out at the Sore Elbow Forge on Friday September 27th starting at 7:00 p.m. We’re going to do an inventory of our club scopes and see what needs to be worked on. Bring your own scope and see what needs to be tightened, collimated, WD-40’d, repaired and more.

  • Trip around the Triangle

    Spot the Stars of the Summer Triangle

    David Prosper

    September skies are a showcase for the Summer Triangle, its three stars gleaming directly overhead after sunset. The equinox ushers in the official change of seasons on September 23. Jupiter and Saturn maintain their vigil over the southern horizon, but set earlier each evening, while the terrestrial planets remain hidden.

    The bright three points of the Summer Triangle are among the first stars you can see after sunset: Deneb, Vega, and Altair.  The Summer Triangle is called an asterism, as it’s not an official constellation, but still a striking group of stars. However, the Triangle is the key to spotting multiple constellations! Its three stars are themselves the brightest in their respective constellations: Deneb, in Cygnus the Swan; Vega, in Lyra the Harp; and Altair, in Aquila the Eagle. That alone would be impressive, but the Summer Triangle also contains two small constellations inside its lines, Vulpecula the Fox and Sagitta the Arrow. There is even another small constellation just outside its borders: diminutive Delphinus the Dolphin. The Summer Triangle is huge!

    The equinox occurs on September 23, officially ushering in autumn for folks in the Northern Hemisphere and bringing with it longer nights and shorter days, a change many stargazers appreciate. Right before sunrise on the 23rd, look for Deneb – the Summer Triangle’s last visible point – flickering right above the western horizon, almost as if saying goodbye to summer.

    The Summer Triangle region is home to many important astronomical discoveries. Cygnus X-1, the first confirmed black hole, was initially detected here by x-ray equipment on board a sounding rocket launched in 1964. NASA’s Kepler Mission, which revolutionized our understanding of exoplanets, discovered thousands of planet candidates within its initial field of view in Cygnus. The Dumbbell Nebula (M27), the first planetary nebula discovered, was spotted by Charles Messier in the diminutive constellation Vulpecula way back in 1764!

    Planet watchers can easily find Jupiter and Saturn shining in the south after sunset, with Jupiter to the right and brighter than Saturn. At the beginning of September, Jupiter sets shortly after midnight, with Saturn following a couple of hours later, around 2:00am. By month’s end the gas giant duo are setting noticeably earlier: Jupiter sets right before 10:30pm, with Saturn following just after midnight. Thankfully for planet watchers, earlier fall sunsets help these giant worlds remain in view for a bit longer. The terrestrial planets, Mars, Venus, and Mercury, remain hidden in the Sun’s glare for the entire month.

    Discover the latest in space science from the NASA missions studying our universe at

    Caption: Once you spot the Summer Triangle, you can explore the cosmic treasures found in this busy region of the Milky Way. Make sure to “Take a Trip Around the Triangle“ before it sets this fall! Find the full handout at

    Caption: This wider view of the area around the Summer Triangle includes another nearby asterism: the Great Square of Pegasus.

    This article is distributed by the NASA Night Sky Network

    NASA’s Night Sky Network program supports astronomy clubs across the USA dedicated to astronomy outreach. Visit to find local clubs, events, and more!

  • SMAS Summer lecture

    Join us on Friday July 26th at the Bozeman Public Library small conference room at 5:00 p.m. as we welcome back to Bozeman Dr. Shane Larson.   Shane will be giving us an update on The Dark Side of the Cosmos: Dark Matter and Energy.
    This is at the Public Library, 626 E Main St. The high school is not available during the summer. Free event, open to the public.

  • Happenings in March

    Our next SMAS club meeting is next Friday, March 29th at 7:00 p.m. at Bozeman High School. We’ll be welcoming Solar System Ambassador Sherre Boothman who will give a presentation on the Apollo Mission 50th Anniversary.

    On Saturday March 30th you are invited to join us at the Bozeman Public Library at 4:00 p.m. to learn more about Globe at Night and their 2019 Adopt-A-Street campaign. More info can be found here: Adopt-A-Street

  • SMAS February 2019 meeting

    Join us on Friday February 22nd at 7:00 p.m. for our next meeting.  Part of our Winter Lecture Series, we’ll hear from SMAS club member Russ Lucas and John Harrington from Boston, both are Glacier Astronomy VIP’s in the park. They will give us an update on the new observatory, plans for the future including public outreach this summer. We’ll be meeting in the Bozeman High School Bridger Charter Academy wing, room C-6.  Free and open to the public.


    UPDATE: Here is the link to the Glacier National Park Astronomy VIP Program.  Thanks to Russ, John and Mike for the great presentation!  We can’t wait for updates on your progress.

  • Find Neptune this week

    Have you seen the blue of Neptune?  If not, finding it this week gets a bit easier thanks to Mars and the Astro League.  See the attached diagram, for more info visit the Astro League website – while you are there check out the observing clubs – which is included in you SMAS dues.

    FYI – speaking of dues… it is election time and time for dues.  Check the tab above for info about paying your dues, or bring it to a meeting.  Our next meeting is 12/7/2018!

  • Comet viewing 2018

    There are several comets that should be visible with telescopes over the next several weeks. As the comets come in closer one should be visible with binoculars in December – and depending on how it interacts with the inner solar system, might become visible to the naked eye.

    This website allows you to select the date you will be viewing the comets and a map of the sky where the comets will be located so you can find them easier.

    On December 13, 2018, comet 46P/Wirtanen will reach perihelion, then on December 16, 2018 it is forecast to reach its brightest, at around mag 6.1. It will lie at a distance of 1.05 AU from the Sun, and at a distance of 0.07 AU from the Earth.

    From Bozeman, it will be visible in the evening sky, becoming accessible at around 17:57 (MDT) as the dusk sky fades, 29° above your eastern horizon. It will then reach its highest point in the sky at 22:27, 65° above our southern horizon. It will continue to be observable until around 03:52, when it sinks to 21° above your western horizon.

    Visit our resource tab for more information.


  • October 2018 SMAS club meeting

    Join us on Friday October 26th at 7:00 p.m. for our next SMAS club meeting. We’ll be meeting at the Bozeman High School Bridger Charter Academy community center aka library, room C-6.  Our agenda includes the 2019 SMAS elections and board  along updates on what the club is up to this Fall and the Winter Lecture series.  Bring along your smart phone or iPad, as we’ll discuss and share some of the best apps that we’ve found and use for astronomy. Then we’ve got a game to test your skills – are you ready for that?  Sounds like fun and a challenge.




  • SMAS site bugged

    downloadWe have been made aware that there have been some issues with some of our tabs. We are working to fix the issues and get the full site up and running again soon.

    Thanks for your patience!

    UPDATE: Everything should be good to go now. Thanks!