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Mercury magazine

Winter 2013 - Volume 42, Number 1

Winter 2013 - Volume 42, Number 1

Table of Contents



[18] Sidewalk Astronomy: Bridge to the Universe, David E. Hostetter
Sidewalk astronomy can be a relatively inexpensive, easy, and effective outreach program

[23] Astronomy is All Around Us, Steve Tidey
Astronomy's cultural influences, handed down through the millennia, are surprisingly many and varied.

[30] Highlight Images of 2012, Paul Deans
Here are a few great cosmic photos acquired during 2012, and where to find them (and others of their ilk).

[35] Astronomy in the News
Solar variability and Earth's climate, more new planets, and the Milky Way's "Tower of Power" -- these are some of the discoveries that recently made news in the astronomical community.


[4] Perspectives, Paul Deans
Mercury's New Look

[5] First Word, Jim Manning

[7] Echoes of the Past, Katherine Bracher
60 Years Ago: The Structure of Our Galaxy

[8] Annals of Astronomy, Clifford J. Cunningham
New Mars, Old Mars

[10] Astronomer's Notebook, Jennifer Birriel
The Milky Way's Rotation Curve

[11] Planetary Perspectives, Daniel D. Durda
Stay Frosty, My Friends

[13] Armchair Astrophysics, Christopher Wanjek
A Universe's Worth of Starlight Measure

[14] Education Matters, David Bruning
Becoming a Slow Thinker

[16] Reaching Out, Bethany Cobb
Communication Conundrum

[17] In Memorium: Sir Patrick Moore

[41] Society Scope/ASP Supporters
New PASP Editor

[44] Sky Sights, Paul Deans
2013 Highlights

[47] Reflections, Paul Deans
Explaining Time to an 11-Year-Old

Sidewalk Astronomy: Bridge to the Universe

by David E. Hostetter

There are a number of reasons to do sidewalk astronomy. I have to give credit here to Jim Mullaney and International Planetarium Society President Dave Weinrich for one of the best reasons -- they call it the photon connection. Sure, you can set up a telescope with a camera and monitor and show spectacular views to several people at once, but it's just a picture. No matter how good it is, there's a better one somewhere on the Internet. But there's something about physically looking through a telescope -- having that live light actually hit your eye -- that really resonates with the public. To me, one of the best reasons to do sidewalk astronomy is to make it easy for people to look through a telescope.

And that's another good reason to do it: sidewalk astronomy gets you out into the community, reaching people who otherwise might not think to visit the science museum (or even know you exist). Put your facility name on the telescope and hand them a little program schedule -- it's all great marketing. Do the same event year after year and people will start to notice. It helps make your planetarium or science center part of the community life.

Finally, another reason to do sidewalk astronomy is that it's just plain fun.

Astronomy is All Around Us

by Steve Tidey

Picture the scene. You wake up one morning and decide to make a mental note of all the things you come across during the next 48 hours that have an astronomical connection. You're not an astronomer or a planetarian or even a science teacher, but you do have a more than passing interest in astronomy.

The heavens do influence us, you muse as you lay in bed, staring at the ceiling and listening to the radio. Astrologers were right, but for the wrong reason. For thousands of years the planets and stars haven't had any spare time to affect our personalities; they've been far too busy inspiring our creative intellects and influencing the development of numerous calendar systems. And there are many everyday words and sayings of astronomical origin that are seen in the world of commerce. The more you think about it, the more you suspect that astronomy's cultural influences, handed down through the millennia, are surprisingly many and varied.

Highlight Images of 2012

by Paul Deans

There are many highlight lists created as the old year gives way to the new, so why not one in Mercury? Astronomy is a visual science, and now astronomers often combine images from a wide array of sources -- the back cover shot from the Hubble Space Telescope and the Karl G. Jansky Very Large Array radio telescope is a prime example -- to create stunning photos.

But if you're going to flaunt astronomical beauty, you have to know where to find it, and that's the secondary motive for publishing a few 2012 highlight photos in Mercury. Of course, if you check out Astronomy Picture of the Day (APOD), you're sure to find a steady stream of stunning images. But remember, many of the photos that appear in APOD are copyrighted, so be careful how you use them, and don't publish them without permission. On the other hand, the following images are all in the public domain, so their use for educational purposes doesn't require permission. As usual, links are highlighted so you can acquire the images (and others) for yourself. Enjoy.

Astronomy in the News
Cassini Suggests Icing on a Lake


It's not exactly icing on a cake, but it could be icing on a lake. A new paper by scientists on NASA's Cassini mission finds that blocks of hydrocarbon ice might decorate the surface of existing lakes and seas of liquid hydrocarbon on Saturn's moon Titan. The presence of ice floes might explain some of the mixed readings Cassini has seen in the reflectivity of the surfaces of lakes on Titan.

One of the most intriguing questions about these lakes and seas is whether they might host an exotic form of life, said Jonathan Lunine, a paper co-author and Cassini interdisciplinary Titan scientist at Cornell University, Ithaca, N.Y. And the formation of floating hydrocarbon ice will provide an opportunity for interesting chemistry along the boundary between liquid and solid, a boundary that may have been important in the origin of terrestrial life.

Titan is the only other body besides Earth in our solar system with stable bodies of liquid on its surface. But while our planet's cycle of precipitation and evaporation involves water, Titan's cycle involves hydrocarbons like ethane and methane. Ethane and methane are organic molecules, which scientists think can be building blocks for the more complex chemistry from which life arose. Cassini has seen a vast network of these hydrocarbon seas cover Titan's northern hemisphere, while a more sporadic set of lakes bejewels the southern hemisphere.