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Mercury magazine

Winter 2017 - Volume 46, Number 1

Winter 2017 - Volume 46, Number 1

Table of Contents



[18] Making the Most of Limited Resources, Michelle Nichols
You don’t need expensive equipment to enjoy the upcoming solar eclipse; even crackers can be useful.

[24] Party off the Path, Vivian White with Mike Reynolds
Not everyone can journey to totality. Here are some suggestions for holding a partial eclipse event.

[29] Practice, Practice, Practice for a Perfect Solar Eclipse Event, Larry Metcalf
Don’t try to do too much during a solar eclipse; you might miss out on the experience.

[33] Astronomy in the News
Bladed terrain on Pluto, an astronomer makes a bold prediction, and a fast radio burst is finally identified. These are some of the discoveries that recently made news in the astronomical community.


[4] Perspectives, Paul Deans
A Far View

[5] First Word, Linda Shore
Meet Us at the Moonrise

[8] Annals of Astronomy, Clifford J. Cunningham
A Victorian Amateur Astronomer

[9] Astronomer’s Notebook, Jennifer Birriel
Detecting Exoplanets on the Cheap

[11] Planetary Perspectives, Emily Joseph
Go Atlas, Go Centaur, Go OSIRIS-Rex

[12] Armchair Astrophysics, Christopher Wanjek
‘Eclipse’ Reveals Insights to Potentially Habitable Planet

[14] Strange New Worlds,  Harvard Smithsonian Center for Astrophysics
Is Earthly Life Premature from a Cosmic Perspective?

[15] Education Matters, Brian Kruse
Creating a Revolution, One Eclipse at a Time

[16] Reaching Out, Space Science Institute
Public Libraries to Receive Solar Viewing Glasses

[42] ASP Tidings
Call for Nominations for ASP Awards

[44] Sky Sights, Paul Deans
A Subtle Lunar Eclipse and a Bright-Star Occultation

[47] Reflections, NASA/ESA
A Swirl of Filaments

Making the Most of Limited Resources

by Michelle Nichols

During the eclipse of August 21st at the Adler Planetarium (Chicago), we will see about 90% of the Sun hidden by the Moon. We’re planning for several thousand people to head to our Museum Campus area that houses the Adler Planetarium, the Field Museum, and the Shedd Aquarium, and we hope to have satellite viewing locations elsewhere in Chicago. We are also partnering with the Chicago Public Library system to bring viewing experiences to branches all around the city. We’re excited that Chicagoans will get to look up that day!

Sundials are a fun way to pass the time before and after an eclipse. You can make a real sundial, but to do it properly, you’ll have to account for your latitude and the different hour-angle sizes of your sundial. If you look at decorative sundials, all the hour angles (the spacing between each hour on the dial) are often the same, so they’re rather useless for telling time! Of course, if you’re just making fun sundials, you don’t need to be so particular!

Party off the Path

by Vivian White, with Mike Reynolds

Many people are not going to have the resources to get to the path of totality. A great deal of time and energy is being spent talking about being in the path, but our mission is to get resources to underserved communities who will not be able to reach totality. There will be people and schools, mere miles outside the path of totality, who will miss it — in fact, most of the US will be “left in the light.” We’re not just thinking about folks in Maine and Texas, we’re talking about everywhere outside the path (see the map on the previous page). So here are some ideas and innovative ways to celebrate the partial eclipse.

Whether you’re inside the path of totality or not, the eclipse is an event that lasts several hours. So you have plenty of time to see the partial phases, take photos, and to do activities. If you’re outside the path, there is absolutely no rush to do anything during the eclipse.

Practice, Practice, Practice for the Perfect Solar Eclipse

by Larry Metcalf

It’s important to keep in mind that you don’t want to become so caught up in so many activities during the eclipse that you get distracted and don’t experience the entire event. So let’s consider four aspects that you might want to practice prior to doing an eclipse event: safe viewing, location, still photography, and video. And remember the five “P’s”: Proper Planning Prevents Poor Performance.

Don’t try to organize an event at the last minute. You need to think about your guidelines for safety. You need to find a location with an unobstructed view, facilities, parking, and easy access. Visit the location and determine opportunities to improve your plan. Develop checklists for equipment and volunteer duties. Develop and modify your plans for still and/or video photography — and practice, practice, practice. But above all, make sure you are able to enjoy the eclipse.

Will Earth Still Exist Five Billion Years from Now?

KU Leuven Institute of Astronomy

What will happen to Earth when, in a few billion years’ time, the Sun is one hundred times bigger than it is today? Using the most powerful radio telescope in the world, an international team of astronomers has set out to look for answers in the star L2 Puppis. Five billion years ago, this star was very similar to the Sun as it is today.

“Five billion years from now, the Sun will have grown into a red giant star, more than a hundred times larger than its current size,” says Professor Leen Decin from the KU Leuven Institute of Astronomy. “It will also experience an intense mass loss through a very strong stellar wind. The end product of its evolution, seven billion years from now, will be a tiny white dwarf star.” This metamorphosis will have a dramatic impact on the planets of our solar system. Mercury and Venus, for instance, will be engulfed in the giant star and destroyed.

“But the fate of the Earth is still uncertain,” continues Decin. “We already know that our Sun will be bigger and brighter, so that it will probably destroy any form of life on our planet. But will the Earth’s rocky core survive the red giant phase and continue orbiting the white dwarf?”

To answer this question, an international team of astronomers observed the evolved star L2 Puppis using the ALMA radio telescope. This star is 208 light-years away from Earth.

“We discovered that L2 Puppis is about 10 billion years old,” says Ward Homan from the KU Leuven Institute of Astronomy. “Five billion years ago, the star was an almost perfect twin of our Sun as it is today, with the same mass. One third of this mass was lost during the evolution of the star. The same will happen with our Sun in the very distant future.”