Southwest Montana Astronomical Society

Amateur Astronomy Under The Big Sky
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  • How will we finally image the event horizon of a black hole?

    Posted on December 11th, 2015 Lynn Powers No comments

    One hundred years ago, Albert Einstein first put forth his theory of General Relativity, which laid out the relationship between spacetime and the matter and energy present within it. While it successfully recovered Newtonian gravity and predicted the additional precession of Mercury’s orbit, the only exact solution that Einstein himself discovered was the trivial one: that for completely empty space. Less than two months after releasing his theory, however, the German scientist Karl Schwarzschild provided a true exact solution, that of a massive, infinitely dense object, a black hole.

    One of the curious things that popped out of Schwarzschild’s solution was the existence of an event horizon, or a region of space that was so severely curved that nothing, not even light, could escape from it. The size of this event horizon would be directly proportional to the mass of the black hole. A black hole the mass of Earth would have an event horizon less than a centimeter in radius; a black hole the mass of the sun would have an event horizon just a few kilometers in radius; and a supermassive black hole would have an event horizon the size of a planetary orbit.

    Our galaxy has since been discovered to house a black hole about four million solar masses in size, with an event horizon about 23.6 million kilometers across, or about 40 percent the size of Mercury’s orbit around the sun. At a distance of 26,000 light years, it’s the largest event horizon in angular size visible from Earth, but at just 19 micro-arc-seconds, it would take a telescope the size of Earth to resolve it – a practical impossibility.

    But all hope isn’t lost! If instead of a single telescope, we built an array of telescopes located all over Earth, we could simultaneously image the galactic center, and use the technique of VLBI (very long-baseline interferometry) to resolve the black hole’s event horizon. The array would only have the light-gathering power of the individual telescopes, meaning the black hole (in the radio) will appear very faint, but they can obtain the resolution of a telescope that’s the distance between the farthest telescopes in the array! The planned Event Horizon Telescope, spanning four different continents (including Antarctica), should be able to resolve under 10 micro-arc-seconds, imaging a black hole directly for the first time and answering the question of whether or not they truly contain an event horizon. What began as a mere mathematical solution is now just a few years away from being observed and known for certain!


    Article by Ethan Siegel.   Image credit: NASA/CXC/Amherst College/D.Haggard et al., of the galactic center in X-rays. Sagittarius A* is the supermassive black hole at our Milky Way’s center, which normally emits X-ray light of a particular brightness. However, 2013 saw a flare increase its luminosity by a factor of many hundreds, as the black hole devoured matter. The event horizon has yet to be revealed.


  • 2016 SMAS Board of Directors

    Posted on December 7th, 2015 Lynn Powers No comments

    I’d like to thank everyone who came out to the SMAS winter 2015 meeting.  We held our elections then had a great time socializing with all the great food everyone brought in.  A great big Thank You to all the SMAS Executive Board members who have done a great job over the past year.  A list of SMAS current board members can be found here.


  • SMAS Winter meeting 2015

    Posted on November 12th, 2015 Lynn Powers No comments

    We a rapidly closing out 2015.  Our November and December club meetings are combined and we will meet the first Friday in December for our club potluck and elections at the Bozeman Public Library small meeting room.

    At our October club meeting it was unanimously voted on to keep the same board members. Of course it is an open election.  If anyone would also like to throw their name in for a spot on the board  please let us know prior to 11/25/15 so we can let the members know.  An email will be going out to club members with specific information on the potluck.

  • SMAS October 2015 meeting

    Posted on October 26th, 2015 Lynn Powers No comments

    Join us on Friday October 30, 2015 starting at 7:00 p.m. at Bozeman Firestation #3, located at the regional park off of Davis.

    We have several items on our agenda including discussion of Near Earth Objects (NEO) such as “Spooky.”

    “The big asteroid that will zoom past Earth on Halloween may actually be a comet, NASA researchers say.

    The roughly 1,300-foot-wide (400 meters) asteroid 2015 TB145, which some astronomers have dubbed “Spooky,” will cruise within 300,000 miles (480,000 kilometers) of Earth on Halloween (Oct. 31) — just 1.3 times the average distance between our planet and the moon.

    Though 2015 TB145 poses no threat on this pass, the flyby will mark the closest encounter with such a big space rock until August 2027, when the 2,600-foot-wide (800 m) 1999 AN10 comes within 1 Earth-moon distance (about 238,000 miles, or 385,000 km), NASA officials said.

    Astronomers plan to beam radio waves at 2015 TB145 on Halloween using a 110-foot-wide (34 m) antenna at NASA’s Deep Space Network facility in Goldstone, California, then collect the reflected signals with the GreenBank Telescope in West Virginia and Puerto Rico’s Arecibo Observatory.

    Such work should reveal key details about the space rock’s size, shape, surface features and other characteristics — including, perhaps, its true identity.

    “The asteroid’s orbit is very oblong with a high inclination to below the plane of the solar system,” Lance Benner, of NASA’s Jet Propulsion Laboratory in Pasadena, California.

    “Such a unique orbit, along with its high encounter velocity — about 35 kilometers or 22 miles per second — raises the question of whether it may be some type of comet,” added Benner, who leads NASA’s asteroid radar research program. “If so, then this would be the first time that the Goldstone radar has imaged a comet from such a close distance.”

    Asteroid 2015 TB145 will be too faint to spot on Halloween with the naked eye, but anyone who’s interested can get a look at the object online, thanks to live telescope views provided by the Slooh Community Observatory and the Virtual Telescope Project.

    The Virtual Telescope Project will air a webcast at 8 p.m. EDT on Oct. 30 (0000 GMT on Oct. 31), while Slooh’s broadcast begins at 1 p.m. EDT (1700 GMT) on Oct. 31.”

  • White House Astronomy Night: A Celebration of Science, Technology, and Space

    Posted on October 9th, 2015 Lynn Powers No comments

    Join the Southwest Montana Astronomical Society as we celebrate the White House Astronomy Night.  Astronomy clubs around the nation will be heading to the lawn with telescopes to view the night sky.  We will be at the Bozeman Public Library front lawn Monday October 19, 2015 starting at 6:30 p.m.  Starting off with a short talk “What’s up in our night sky”, followed by viewing through telescopes.

    To find out more about the White House Astronomy Night check out this link.

    The Bozeman Public Library is located at 626 East Main Street, Bozeman.

  • September SMAS Club meeting

    Posted on September 24th, 2015 Lynn Powers No comments

    Join us on Friday September 25, 2015 at 7:00 p.m. for our next SMAS club meeting.  We will be meeting at Bozeman Fire station #3. (

    We will be viewing some of the Apollo Lunar Samples.  Six missions went to the Moon and brought back 800 pounds of samples, including rocks and soil, from the highlands to the mares.  We’ll also discuss the Super lunar eclipse (which happens on Sunday evening).  Followed by viewing the moon through telescopes.



  • International Observe the Moon Night – September 19th

    Posted on September 14th, 2015 Lynn Powers No comments

    Join SMAS on Saturday September 19th from 6:00-7:30 p.m. at the Emily Dickinson Elementary School playground for an evening of activities and observing the Moon.  This is the 5th year that SMAS has participated in the global event.

    In 2012, students from Emily Dickinson were chosen as the winners of the NASA contest to name the twin probes from the GRAIL mission.  The school was given a telescope so students could continue to observe our dark skies and the Moon.

    Students in the 4th and 5th grade will also be treated to an up close look at Apollo lunar samples.  During the 6 Apollo missions, 800 pounds of lunar dirt and rocks were brought back.

  • The Great American Eclipse 2017

    Posted on August 21st, 2015 Lynn Powers No comments

     Two years to go! On the morning of August 21st 2017 the Great American Eclipse will take place — where will you be? Bozeman will only experience a partial eclipse with 95% coverage at approximately 11:35 a.m. If you want to see/experience totality you will need to head south to Idaho or Wyoming.

    Here is a link to the interactive NASA eclipse map to check out your location:…/SEgo…/SE2017Aug21Tgoogle.html
    Need 2017 eclipse swag? Check out this out:

  • Astronomy Lecture

    Posted on August 16th, 2015 Lynn Powers No comments

    Save the date!  August 20, 2015. 7:00 p.m. at the Hagar Auditorium.

    “From the Big Bang to Black Holes: Time, the Universe, and Everything”
    Speaker: Janna Levin

    Professor of Physics and Astronomy at Barnard College of Columbia University
    Author of “How the Universe Got Its Spots” and “A Madman Dreams of Turing Machines”
    And a link to Janna’s TEDx talk:
    Janna Levin: The sound the universe makes | Talk Video |
    We think of space as a silent place. But physicist Janna Levin says the universe has a soundtrack — a sonic composition that records some of the most dramatic events in outer space. (Black holes, for instance, bang on spacetime like a drum.) An accessible and mind-expanding soundwalk through the universe.


  • International Observe the Moon Night

    Posted on August 13th, 2015 Lynn Powers No comments

    International Observe the Moon Night (InOMN) is an annual world-wide public engagement program that encourages observation, appreciation, and understanding of our Moon and its connection to NASA planetary science and exploration. Everyone on Earth is invited to join the celebration by attending the SMAS InOMN event.  Watch for more info to come!