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Mercury Magazine Autumn 2018

Mercury Magazine

Contents and Select Excerpts
Vol. 47 No. 4
Autumn 2018

The Autumn 2018 issue of Mercury is LIVE!

Featured in this issue:

  • We live on a planet that is undergoing dramatic global transformations thanks to climate change—NASA is monitoring the gravity of ice to track these transformations.
  • In deep space, NASA’s OSIRIS-REx is approaching asteroid Bennu, but mission controllers must learn how to navigate this mysterious space rock on the fly.
  • Meanwhile, scientists are pondering the Ringed Planet and its enigmatic hexagon—what did Cassini see before the end of its mission?

We also have our regular columnists covering everything from observing the next Mercury transit, how a strange little galaxy is revealing new information about dark matter, some astronomical history, stories from the ASP’s educators and research insights, plus stunning space imagery, news and opinion. Don’t miss out! Download your copy of Mercury today!

This page contains the table of contents and select excerpts only and is not a complete reproduction of this issue. Complete content for online Mercury is available to ASP members and institutional subscribers. Already a member? You can retrieve the latest issue of Mercury by logging into the ASP membership portal.

Table of Contents

[9] Space News
A rundown of some of the most exciting developments in space and time.

[29] Cosmic Views, Jason Major
An Earthly shadow on an alien world.

[30] The Gravity of Climate Change, Matthew R. Francis
The GRACE Follow-On mission measures the effects of climate change through fluctuations in Earth’s gravitation.

[35] Learning to Fly, Steve Murray
NASA’s asteroid sample return mission OSIRIS-REx will require operators to learn new navigation skills on the job.

[42] Saturn’s Six-Sided Storm, Tracy Staedter
New analysis from Cassini stirs up even more intrigue around the hexagonal jet stream in the Ringed Planet’s enigmatic atmosphere.


[3] Perspectives, Ian O’Neill
Our Space Robot Family Loses Two

[4] First Word, Linda Shore
The Astronomy Bucket List

[6] ASP News
ASP Awards Announced!

[14] Annals of Astronomy, Clifford J. Cunningham
Of Books and Time

[16] Research Focus, M. Katy Rodriguez Wimberly
The Rarest of Galactic Pokémon

[18] Astronomer’s Notebook, Jennifer Birriel
The Next Transit of Mercury: A Year to Prepare

[20] Armchair Astrophysics, Christopher Wanjek
GRBs Have “Time-Reversed” Pulses of Light

[22] Education Matters, Brian Kruse
Finding Some Lunar Inspiration

[25] A Little Learning, C. Renee James
Back in My Day

Opportunity In Limbo (News)

By Ian O’Neill

Opportunity explores the Martian surface

Opportunity explores the Martian surface

In the Summer 2018 issue of Mercury, Tracy Staedter encapsulated the anxiety surrounding NASA’s Mars Exploration Rover Opportunity’s silence in her feature “Opportunity Sleeps,” writing: “This is either an obituary or a story of survival.” Sadly, three months on, Opportunity’s persisting silence could mean grim news for the veteran robot.

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An Earthly Shadow on an Alien World (Cosmic Views)

By Jason Major


Hayabusa2 at asteroid Ryugu. Credit: [JAXA]

There was a little black spot on a near-Earth asteroid on Sept. 21, 2018, when the dark shadow cast by Japan’s Hayabusa2 spacecraft was imaged on asteroid 162173 Ryugu from about 80 meters (260 ft). The structure of the 6-meter (20-ft) -wide spacecraft with solar panels outstretched is clear against the rocky surface of Ryugu, a rubble-strewn asteroid some 336 million kilometers (208 million miles) from Earth.

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The Gravity of Climate Change (Feature)

By Matthew R. Francis

Antarctic Pine Island Glacier

The Antarctic Pine Island Glacier calved a huge block of ice in January 2017, the latest in a series of events that emphasize the glacier’s growing fragility. [USGS]

Orbiting spacecraft are an essential tool for mapping worlds in the Solar System, providing information about everything from landforms to magnetic fields. Repeated monitoring helps scientists measure variations in a planet as the seasons change. That’s particularly true for the world we know best, and one that is experiencing the biggest variations of all the planets: Earth.

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Learning To Fly (Feature)

By Steve Murray


This artist’s impression shows NASA’s OSIRIS-REx carrying out its deep space maneuver in 2016 to put it on course for asteroid Bennu. [University of Arizona]

The main objective of the NASA OSIRIS-REx mission will be realized in 2020, when the spacecraft gathers up a sample of asteroid Bennu. Operating so close to a body with virtually no gravity will be risky, so mission science and engineering teams will be cautiously exploring the asteroid before moving in for the final maneuver. There will be a lot to learn over the next few months as the spacecraft travels in company with asteroid Bennu.

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Saturn’s Six-Sided Storm (Feature)

By Tracy Staedter

Saturn's Hexagon

This image of the north pole of Saturn shows a high-resolution view of the planet’s hexagon
that NASA’s Cassini mission captured in 2012. [NASA/JPL-Caltech/SSI/Hampton University]

When the Voyager 1 and 2 spacecraft flew by Saturn in the early 1980s as part of their mission to study the outer solar system, they found something extraordinary: a 20,000-mile-wide vortex at the Ringed Planet’s north pole with a hexagon-shaped boundary. In the 1990s, the Hubble Space Telescope imaged the hexagon, too. And then, in 2004, the Cassini space probe arrived at Saturn, and for 13 years orbited the planet, recording images with a variety of instruments. Recent analysis of some of the data indicates that the hexagonal feature might be a wall of invisible wind hundreds of miles tall.

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