NASA Space Place – Triple Treat

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 May, 2013.

By Dr. Ethan Siegel

2013february2_spaceplaceThe solar system is a busy place, with five wandering planets visible to the naked eye alone. When any two pass close by each other from our point of view, we see an astronomical conjunction, but on very rare occasions, three planets will find themselves grouped together: a triple conjunction. Towards the end of May, Mercury, Venus and Jupiter will treat us to the best triple conjunction in years.

On May 25th, Mercury will pass within 1.4° of Venus, then two days later Mercury comes within 2.4° of Jupiter, and finally on the 28th, Jupiter and Venus approach within 1° of one another. If it weren’t for the slight orbital tilt of our solar system’s planetary orbits, these conjunctions would all be occultations instead. During the nights of May 26th-27th, all three planets are visible immediately after sunset within the same 3° field of view, with the triple conjunction peaking in a triangular shape on the 26th. (For scale, the full Moon subtends about 1/2°.) The three planets appear close together for a few days more, making a line in the sky on the 30th/31st.

How does this happen? Mercury and Venus race around the Sun far faster than Earth, with Mercury completing more than four revolutions around the Sun for each one that Earth makes. At the same time, Jupiter is far slower, taking 12 years to orbit just once around the Sun. Jupiter’s been high in the sky during the early parts of the night, but steadily lowers throughout May as Earth continues to move away from it, approaching its maximum distance from Earth. Mercury and Venus, meanwhile, begin to move out from behind the Sun during May: Venus at the beginning of the month and Mercury in the middle.

Thus, during this triple conjunction, all three planets will be on the far side of the Sun, something that happens just 25% of the time in triple conjunctions involving Mercury and Venus! If you telescopically resolve these planets into disks, you’ll see our inner worlds in a nearly-full gibbous phase. Jupiter will appear largest in terms of angular diameter, followed by Venus and lastly by Mercury. Just a year ago, during its now-famous transit, Venus took up more than a full arc-minute in the sky; during this conjunction, it will just one-sixth that angular size and less than a third the apparent diameter of Jupiter. Nevertheless, Venus will still be more than six times as bright as Jupiter during this time, outshining all night-sky objects other than the Moon. Closer conjunctions of two naked-eye planets are frequent, but getting three or more like this happens just once or twice per decade, so don’t miss your chance to see it.

And speaking of occultations, The Space Place has a great kid-friendly explanation of the Venus transit and solar eclipses of 2012 at spaceplace.nasa.gov/venus-transit.

Dr. Ethan Siegel, a theoretical astrophysicist, is a professor at the University of Portland (OR) and Lewis & Clark College.

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

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Caption: The image shows the configuration of Mercury, Venus, and Jupiter in the western sky just after sunset on May 26, 2013. Insets show the relative size appearance of the planets on that date.

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/

CNYO Observing Log: Beaver Lake Nature Center, 2 May 2013

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Greetings fellow astrophiles,

May 2nd served as the rain date (due to rapidly-overcasting conditions on April 25th) for our first Beaver Lake Nature Center lecture of the year – The Guiding & Wandering Stars – Key Northern Constellations & Planet Observations. On hand to run scopes and engage in lecture duties were the author with a 12.5″ New Moon Telescope Dobsonian, Larry Slosberg with one Meade SCT and Bob Piekiel with another.

The Constellations have been with us for thousands of years, but there are only a few good, clear nights each month to memorize their positions as they slowly move across the sky! This outdoor lecture by the CNY Observers (www.cnyo.org) will briefly describe the history and importance of the Constellations as mythological, agricultural, and navigational guides, then will describe a simple system to begin to learn their relative positions. At the same time, Jupiter and Saturn are on opposite sides of the Southern sky, making excellent targets for binocular and telescope observing. Free and open to the public.

While the week including May 2nd will be known to some as a particularly bad week for maple tree allergies, the nighttime sky stayed quite clear and the bugs eventually froze around us to produce an excellent session. The attending crowd of about 35 served as test subjects for both our two new brochures (How The Night Sky Moves and Guide For New Observers) and our first official completely outdoors (Powerpoint-free) lecture (which, despite astronomy being such a visual hobby, worked will with just the brochure contents). In anticipation of some nighttime brochure reading, I put together some red light flashlights on the cheap locally. For anyone attempting similar, I found a four-pack of Dorcy AAA 6 LED Flashlights at Dicks Sporting Goods for $10. Some very minor surgery is needed to remove the top caps, but conversion to red light flashlights is straightforward with the help of a four-layer stack of red acetate purchased many moons ago from Commercial Art Supply in Syracuse.

406px-EB1711_Armillary_SphereDespite a little confusion about the start time (7:30 or 8:00), everyone had pulled in by 7:45 p.m., so we began the session with a good 30 minutes of physics. The goal of these Beaver Lake lectures is to not only observe objects, but to explain why the sky moves as it does so those trying to learn new constellations will understand what to expect both over the course of a night and over the course of a year. This began at the ground floor – understanding how the Earth moves around the Sun. With the help of an armillary sphere (which holds the Earth at its 23 degree tilt – see the image at left from wikipedia), the Earth’s movement around the Sun was demonstrated, specifically showing that the rotation axis stays pointed the same way as we revolve – thus resulting in Polaris appearing not to move over the course of the year despite the Earth shifting position by 300 million kilometers (2 astronomical units) every 6 months. Knowing that Polaris is always in the same place in the sky (whether it’s daytime or not) leads smoothly into a discussion of the circumpolar constellations and the benefit of learning these six constellations first (for this discussion and some how-to’s, I refer you to the CNYO brochure: Guide For New Observers).

Running a sunset-to-late-night session with a non-cycling crowd has (at least) two distinct advantages. First, the importance of dark adaption and the need to avoid smart phones (or avoid their use around others) can be stressed early in the evening. While enforcing protocols to maintain dark adaption at any kind of public lecture is usually a losing battle, anyone answering a phone did it in a very non-obvious manner, which was most welcome. Second, the mechanics of my Dobsonian telescope and Larry and Bob’s two motorized SCTs could be presented while still visible to attendees. More importantly, the proper observing technique for all could be demonstrated by showing (a) how to approach an eyepiece (I tell people to put their hands behind their back and simply lean into the eyepiece) and (b) just how easy it is to nudge a scope away from its target. Specifically for the Dob, I’m sure anyone who’s brought their scope to a public session has had at least one person lean on or pull closer an eyepiece. I’m pleased to report that, once the observing started, our collective intro to scope workings made my Dob-running life simple with no unplanned re-adjustments (just adjustments of the unmotorized kind).

As stated in a previous post (2013 March 8 – At The Syracuse Inner Harbor), new observers are best introduced to observing with easy objects that don’t require training. Deep, dim, distant galaxies are not useful starters for someone with no background in eyepiece observing. For my part, a good 70 minutes were spent on Jupiter (low in the Western Sky with all four Galilean moons present), Saturn (low in the Eastern Sky and my first view of it this year), Arcturus in Boötes (its shimmering in the sky both with and without magnification was a point of discussion for several near my scope), M13 (the globular cluster in Hercules, which served as a first “way out” object and an example of using the constellations as a “coarse adjustment” for finding Messier and other objects), and the pair Alcor and Mizar in the handle of the Big Dipper/tail of Ursa Major (to show the separation and additional detail that comes with magnification).

With a much smaller crowd around 9:30 p.m., I did treat a few interested parties to some more difficult observing in my scope – The Leo Triplet – after first briefly explaining the mechanics of averted vision. Of the five people who looked, all could make out M65, all could at least tell that something “was there” where M66 rested, and three people could tell that “something else” was there at NGC 3628‘s position. And I did miss a golden opportunity to observe NGC 4565 (my personal favorite) in Coma Berenices.

We closed up shop at 10 p.m., just as Cygnus and Lyra began to peak out over the horizon and announce the approaching return of our Summer Constellations. I am pleased to report that we will be hosting a Summer Session on Thursday, August 8th (with an August 15th rain date) where we will again do a little bit of mechanics and instruction outdoors, followed by Saturn, Venus, and all that our summer view of the Milky Way can provide.

August 8 – Stargazing with CNY Observers & Observing

CNY Observers (CNYO) hosts an introductory lecture to the Night Sky, focusing on planets and other objects observable during August and September.  Part of the lecture will discuss some simple ways to learn the Constellations, while the rest of the lecture will provide details about meteor showers, observing satellites and the ISS, and the ever-expanding description of our own Solar System.  If time and weather permits, some early evening views of Venus and Saturn will be had from the Beaver Lake parking lot.  Free for members; $2 for nonmembers.

TACNY Junior Cafe Scientifique: “The Chemistry of Color: An Exploration of Paints from Art Forensics to Cosmetics”

Saturday, May 18, 9:30-11:00am

Milton J Rubenstein Museum of Science & Technology, Syracuse NY



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We will look at how paints are made for different applications from cosmetics to art. A few stories of paint forensics will be presented. How can one tell whether an old painting is not a recent forgery?

People interested in learning more about the chemistry of color are invited to attend the free Junior Cafe presentation on Saturday, May 18, from 9:30 a.m. to 11 a.m. at the Milton J. Rubenstein Museum of Science and Technology (MOST) in Syracuse’s Armory Square. Walk-ins are welcome, but we ask that people RSVP by emailing jrcafe@tacny.org by May 16, 2013.

Presenter: Ivan V. Korendovych, PhD, is an Assistant Professor in the Department of Chemistry at Syracuse University. Dr. Korendovych received his PhD from Tufts University for his work on oxygen activation. He then moved on to the University of Pennsylvania Medical School where he developed small protein catalysts. Since 2011, he has taught at Syracuse University. His current research interests are focused on discovery of antimicrobial drugs as well as creating biosensors for metals. Dr. Korendovych is a recipient of the 2007 Young Investigator Award from the American Chemical Society in Inorganic Chemistry.

TACNY Junior Cafe Scientifique

TACNY Junior Cafe Scientifique, a program for middle-school students founded in 2005, features discussions about topics in the fields of science, technology, engineering and mathematics in an informal atmosphere and seeks to encourage students to consider careers in these areas. Students must be accompanied by an adult and can explore the MOST at no cost after the event.

Technology Alliance of Central New York

Founded in 1903 as the Technology Club of Syracuse, the nonprofit Technology Alliance of Central New York’s mission is to facilitate community awareness, appreciation, and education of technology; and to collaborate with like-minded organizations across Central New York.

For more information about TACNY, visit www.tacny.org.