Autumn 2018 - Volume 47, Number 4
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.
Departments
[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
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.
An Earthly Shadow on an Alien World (Cosmic Views)
By Jason Major
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.
The Gravity of Climate Change (Feature)
By Matthew R. Francis
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.
Learning To Fly (Feature)
By Steve Murray
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.
Saturn’s Six-Sided Storm (Feature)
By Tracy Staedter
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.
