Monthly Archives: September 2014

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NASA Space Place – Twinkle, Twinkle, Variable Star

Poster’s Note: One of the many under-appreciated aspects of NASA is the extent to which it publishes quality science content for children and Ph.D.’s alike. NASA Space Place has been providing general audience articles for quite some time that are freely available for download and republishing. Your tax dollars help promote science! The following article was provided for reprinting in September, 2014.

By Dr. Ethan Siegel

2013february2_spaceplaceAs bright and steady as they appear, the stars in our sky won’t shine forever. The steady brilliance of these sources of light is powered by a tumultuous interior, where nuclear processes fuse light elements and isotopes into heavier ones. Because the heavier nuclei up to iron (Fe), have a greater binding energies-per-nucleon, each reaction results in a slight reduction of the star’s mass, converting it into energy via Einstein’s famous equation relating changes in mass and energy output, E = mc2. Over timescales of tens of thousands of years, that energy migrates to the star’s photosphere, where it’s emitted out into the universe as starlight.

There’s only a finite amount of fuel in there, and when stars run out, the interior contracts and heats up, often enabling heavier elements to burn at even higher temperatures, and causing sun-like stars to grow into red giants. Even though the cores of both hydrogen-burning and helium-burning stars have consistent, steady energy outputs, our sun’s overall brightness varies by just ~0.1%, while red giants can have their brightness’s vary by factors of thousands or more over the course of a single year! In fact, the first periodic or pulsating variable star ever discovered—Mira (omicron Ceti)—behaves exactly in this way.

There are many types of variable stars, including Cepheids, RR Lyrae, cataclysmic variables and more, but it’s the Mira-type variables that give us a glimpse into our Sun’s likely future. In general, the cores of stars burn through their fuel in a very consistent fashion, but in the case of pulsating variable stars the outer layers of stellar atmospheres vary. Initially heating up and expanding, they overshoot equilibrium, reach a maximum size, cool, then often forming neutral molecules that behave as light-blocking dust, with the dust then falling back to the star, ionizing and starting the whole process over again. This temporarily neutral dust absorbs the visible light from the star and re-emits it, but as infrared radiation, which is invisible to our eyes. In the case of Mira (and many red giants), it’s Titanium Monoxide (TiO) that causes it to dim so severely, from a maximum magnitude of +2 or +3 (clearly visible to the naked eye) to a minimum of +9 or +10, requiring a telescope (and an experienced observer) to find!

Visible in the constellation of Cetus during the fall-and-winter from the Northern Hemisphere, Mira is presently at magnitude +7 and headed towards its minimum, but will reach its maximum brightness again in May of next year and every 332 days thereafter. Shockingly, Mira contains a huge, 13 light-year-long tail — visible only in the UV — that it leaves as it rockets through the interstellar medium at 130 km/sec! Look for it in your skies all winter long, and contribute your results to the AAVSO (American Association of Variable Star Observers) International Database to help study its long-term behavior!

Check out some cool images and simulated animations of Mira here: www.nasa.gov/mission_pages/galex/20070815/v.html

Kids can learn all about Mira at NASA’s Space Place: spaceplace.nasa.gov/mira/en/.

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Caption: NASA’s Galaxy Evolution Explorer (GALEX) spacecraft, of Mira and its tail in UV light (top); Margarita Karovska (Harvard-Smithsonian CfA) / NASA’s Hubble Space Telescope image of Mira, with the distortions revealing the presence of a binary companion (lower left); public domain image of Orion, the Pleiades and Mira (near maximum brightness) by Brocken Inaglory of Wikimedia Commons under CC-BY-SA-3.0 (lower right).

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

About NASA Space Place

The goal of the NASA Space Place is “to inform, inspire, and involve children in the excitement of science, technology, and space exploration.” More information is available at their website: http://spaceplace.nasa.gov/

Star Party Announcement: Mountains of Stars Amateur Astronomers Weekend, 24-26 October 2014

Greetings fellow astrophiles!

The following announcement came through our website recently. For those not considering a drive South to attend the Kopernik AstroFest that same weekend, consider a drive East for a long weekend under high, dark (hopefully) skies!

First Annual – Mountains of Stars Amateur Astronomers Weekend – In The White Mountains

The Appalachian Mountain Club and the Carthage Institute of Astronomy announce the first annual Mountains of Stars Amateur Astronomers Weekend, to be held October 24th to 26th 2014 at the Appalachian Mountain Club’s Highland Center in Bretton Woods, New Hampshire. Surrounded by the White Mountain National Forest, the Highland Center is a wonderful place to enjoy dark skies. Less than a day’s drive from one-quarter of the US population, the location offers outstanding hiking and outdoor activities, and the area is wonderful for families. Bring your telescopes and observing gear – and several facility telescopes will also be available. The Mountains of Stars Weekend will include opportunities for presentations and short talks, and two nights of dark sky observing around New Moon.

Please contact AMC Reservations at 603-466-2727 or amclodging@outdoors.org for more information or to make a reservation.

The Carthage Institute of Astronomy is a branch of Carthage College, a liberal arts college founded in 1847 and located in Kenosha, WI. The Institute conducts research in astronomy and astrophysics, operates the Griffin Observatory, offers courses in physics and astronomy, and delivers outreach and education programs. The institute’s director is astrophysicist Dr. Douglas Arion, who will be the host of the Mountains of Stars Weekend. He also heads the Galileoscope program, which has delivered more than 200,000 high quality, low cost telescopes for education and outreach to over 106 countries.

Founded in 1876, the Appalachian Mountain Club is America’s oldest conservation and recreation organization. With more than 100,000 members, advocates, and supporters in the Northeast and beyond, the nonprofit AMC promotes the protection, enjoyment, and understanding of the mountains, forests, waters, and trails of the Appalachian region. The AMC supports natural resource conservation while encouraging responsible recreation, based on the philosophy that successful, long-term conservation depends upon first-hand enjoyment of the natural environment.

The Mountains of Stars event is part of an NSF-funded joint Carthage/AMC astronomy outreach and education program, bringing astronomy and nature education to the public.

CNYO Observing Log: Beaver Lake Nature Center, 18 September 2014

Greetings fellow astrophiles,

After a double wash-out for our scheduled August 8/15 event, CNYO made a triumphant return to Beaver Lake Nature Center for one last end-of-Summer public viewing session. While the local meteorologists and the Clear Sky Clock predicting clear, dark skies for the entire evening, the observing itself was still a bit touch-and-go until about 9:00 p.m., when the whole sky finally opened up.

Despite a small snafu with the Beaver Lake events calendar (or, specifically, our lack of presence on it for this rescheduled event), we still managed 10 attendees (and passed the word along to several people there for an event earlier in the evening – I’m also happy to report that Patricia’s attendance justified our meetup group event scheduling!). With four CNYO’ers (Bob Piekiel, Larry Slosberg, Christopher Schuck, and myself) and three scopes present (including Bob Piekiel’s Celestron NexStar 11, Larry Slosberg’s 12” New Moon Telescope Dob, and my 12.5” NMT Dob) this was a great chance for several of the new observers to ask all kinds of questions, learn all the mechanics of observing through someone else’s scope, and, of course, take in some great sights at their own pace.

The 7:00 p.m. setup started promising, with otherwise overcast conditions gradually giving way to clearings to the Northwest. That all changed for the worse around 8:00 p.m. (when everyone showed up), when those same NW skies closed right up again, gradually devouring Arcturus, Vega, and any other brighter stars one might align with. The next hour was goodness-challenged, giving us plenty of time to host a Q+A, show the scope workings, remark on the amount of reflected light from Syracuse, and swing right around to objects within the few sucker holes that opened. And when all looked lost (or unobservable), the 9:00 p.m. sky finally cleared right up to a near-perfect late Summer sky, complete with a noticeable Milky Way band, bright Summer Triangle, and a host of satellites, random meteors, and bright Summer Messiers.

As has been the case for nearly every public viewing session this year, all the new eyes were treated to some of the best the Summer and Fall have to offer. These include:

M13 – The bright globular (“globe” not “glob”) cluster in Hercules
M31/32 – The Andromeda Galaxy (and its brighter, more separated satellite M32)
M57 – The Ring Nebula in Lyra
Herschel’s Garnet Star – To show very clearly that many stars have identifiable colors when magnified
Albireo – To reinforce the color argument above and to show one of the prominent doubles in the Night Sky, right at the tip of Cygnus.
Alcor/Mizar – Did you know that Alcor/Mizar is actually a sextuple star system? Alcor is its own double, each in Mizar is a double, and recent data reveals that the Alcor pair is gravitationally bound to the Mizar quartet.

To the observing list was added a discussion of how to begin learning the constellations. As we’ve discussed at several sessions, the best place to start is due North, committing the circumpolar constellations to memory FIRST. For those unfamiliar, these are the six constellations that never set below the horizon from our latitude (Ursa Minor (Little Dipper), most or Ursa Major (Big Dipper), Cassiopeia, Cepheus, Draco, and Camelopardalis (and if you can find Camelopardalis, you’re ready for anything). We’ve even consolidated all of this material into one of our introductory brochures for your downloading and printing pleasure:

CNYO Guide For New Observers

To my own observing list was added a treat thanks to Bob’s perfect position on the rise of the Beaver Lake parking circle, as he managed to catch Uranus low on the Eastern horizon just before we packed up for the evening. Even with Syracuse’s glow dimming the view, Uranus is a clear sight either in a scope (as a slightly blue-green disc) or through a low-power finder scope.

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Closing at Beaver Lake (including one low-flyer).

We offer special thanks to the Beaver Lake staff, who were fine with us staying as late as we liked (although we still finished up around 10) and who found *all* the light switches for the parking lot. I suspect our next Beaver Lake event won’t happen until the Spring, meaning we hope to see you at one of Bob Piekiel’s Baltimore Woods sessions during the winter – unless we all get inspired to throw extra layers on and organize another winter observing session somewhere, in which case we hope to see you there as well!

CNYO Observing Log: Clark Reservation State Park, 29 August 2014

Greetings fellow astrophiles,

Central New York is a reasonably reasonable place for the reasonably active amateur astronomer. A 10 minute drive away from the center of downtown Syracuse puts one far enough away from enough of the city lights to make bright clusters and galaxies visible, although not necessarily impressive. A 15 to 25 minute drive in the right direction provides skies dark enough to keep any keen amateur occupied for a long evening of Messiers. Those willing to meander their way through a 40 to 50 minute excursion can find some tremendously dark skies fit for subtle NGCs and non-CCD comets. And those of us who host sessions along the Creekwalk know it’s perfectly reasonable for the Moon, Sun, and bright planets (and, if the big globular clusters aren’t out, not much else).

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First setup at Clark Reservation. Click for a larger view.

Clark Reservation State Park leans very much in the near-downtown category, lying about 10 minutes to the Southwest of the Salt City. A two-hour session hosted by Bob Piekiel and assisted by Christopher Schuck and myself revealed Clark Res to be a great harbor for new amateur astronomers wanting to get their feet wet but not ready to be thrown eyepiece-first into the deep abyss offered by Dark Sky locations. Bright constellations are obvious, the planets jump right out, the crescent Moon is a busy structure of mountains and valleys, and the brightest Messier objects are “obvious” to observers looking through the eyepiece, all while the sky is streaked by bright shooting stars and crisscrossed by satellites too numerous to keep track of.

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Summer Triangle panorama. Click for a larger view.

Setup commenced around 7:00 p.m. with Bob, Chris, and I initially spaced in an equilateral-ish triangle to try to maximize the amount of “different” observables. The clear field just west of the main parking lot offered a remarkably open view of the sky, with several large clearings between trees to really let one get low to the horizon for last-look viewing. My initial proposal to Chris to catch the Moon, Saturn, and Mars between one of these South-most clearings seemed reasonable until we stepped over to Bob’s East-most setup – a change of only 50 feet completely opened up the Western Sky. What started as a Summer Triangle then turned into Triangulum, leaving me with dominion over the Eastern Sky and all of the constellations and Messiers Autumn will offer at our zenith.

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Maybe a 4? The light pollution from Clark Res (lower number = better). For Deep Sky objects, not good. For learning the major constellations, not bad. From stellarium.org.

Despite the brightness of Syracuse (and some of the Clark Res safety lights), the sky wasn’t “that bad.” It was certainly a great starting point for new observers who’d only ever recognized the Big Dipper in the late-Summer sky. It was very easy to point out – then reinforce – the Big Dipper, Little Dipper, Pegasus, Cygnus, Lyra, Cassiopeia, the Summer Triangle, and Hercules. The Messiers through my scope were limited to M13, M57 (which was a stretch for the newbies, no doubt about it), and M31/M32 (which, despite the location, looked excellent in a 26mm Nagler), leaving Saturn, Mars, and the Moon to Bob and Chris – this on account of a good-sized group (about 20) who kept in constant rotation between our three scopes. We did have ourselves a prominent Iridium Flare, 6 confirmed meteors, and a host of satellites (which made a few people’s day).

Final pack-up started a little before 10 p.m., requiring bright flashlights and small mops (was quite a damp evening). All in all, Clark Reservation is a good spot for those who want to get their bearings without having to drive too far from home (a nice starter spot for that 10-minute range), and I found myself spending more time with a green laser pointer and some mythology than I did looking through the eyepiece. Attendees didn’t seem to mind, and we all got home by bedtime.

Celestron NexStar GOTO Mount For Sale In CNY

Greetings fellow astrophiles,

From the CNYO Classifieds Department – Local imaging instructor and astrophotographer extraordinaire Stephen Shaner (website) has available a like-new Celestron NexStar GOTO Mount. Details provided below. Interested parties should contact him at stephen@stephenshaner.com.

nexstar-8se-mountI have a Celestron NexStar goto mount I bought last summer and only used a handful of times before I bought a GEM for photography a few weeks later. The mount is basically new and I’d like to see it go to someone who will be able to use it.

This mount is suitable for an 8″ SCT or small refractor and fits any standard Vixen rail. There’s a database of 40,000 objects and the fantastic NexStar controller. It would be great for outreach work since it can run several hours off AA batteries or 12v (and I’m including the optional Celestron AC adapter), is very portable and only takes a few minutes to set up and align. It tracks very well. The mount, tripod and accessories are like new and in the original boxes. $275 if you pick it up at my place.