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Mercury magazine

Summer 2020 - Volume 49, Number 3

Summer 2020 - Volume 49, Number 3

Table of Contents




[21] Space News

A rundown of some of the most exciting developments in space and time.

[27] Cosmic Views

See the Sun up-close, and marvel at one of the first images from the enormous camera accompanying the still-under-construction Vera C. Rubin Observatory

[29] Cataloging the Cosmos

Gaia gathers small details that lead to big insights

[36] Comet NEOWISE Adorned the Northern Skies

2020 needed a win, so the Solar System gave the Northern Hemisphere the brightest comet it’s seen in more than two decades.


[3] Perspectives, Liz Kruesi

Summer of Science

[4] First Word, Linda Shore

On the Importance of Looking Up

[6] Annals of Astronomy, Clifford J. Cunningham

Trip Through the Solar System in 1460

[8] Astronomer’s Notebook, Jennifer Birriel

The Eratosthenes Experiment

[10] Armchair Astrophysics, Christopher Wanjek

Dark Matter Appears to be a Smooth Operator

[12] Research Focus, M. Katy Rodriguez Wimberly

Why Have Our Galactic Neighbors Lost Their Star-forming Oomph?

[15] Education Matters, Brian Kruse

Infecting Students with Enthusiasm for Astrobiology

[17] A Little Learning, C. Renée James & Scott T. Miller

This Doesn’t Bode Well

[42] Reflections, Liz Kruesi

Aurora Above Antarctica

Cataloging the Cosmos (Feature)

By Steve Murray

The European Space Agency (ESA) set a big task for Gaia when it launched the space telescope in 2013: measuring over one billion stars in the Milky Way with unprecedented accuracy. The spacecraft has long since passed that achievement; Gaia’s next data release, its third, will contain information about the positions, velocities, luminosities, and colors of almost double that number of stars. The growing trove of data has already generated fundamental new discoveries about our galaxy and, in 2020, the pace of that productivity is accelerating.

Comet NEOWISE Adorned the Northern Skies (Feature)

By Liz Kruesi

On March 27, 2020, the NEOWISE space mission’s automated data-sifting program flagged a dozen images with an object of interest. A few days later, several telescopes across the world confirmed the object was a comet, and it earned its formal name: Comet C/2020 F3 (NEOWISE). Those further observations also showed the comet would get close to the Sun, just outside Mercury’s orbit. The comet swung closest to the Sun in early July, and it became the brightest comet the Northern Hemisphere has seen in decades. Observers — both professional and amateur — around the world tracked and studied how Comet NEOWISE brightened and evolved.

Swing by the Sun (Cosmic Views)

By Liz Kruesi

The Solar Orbiter spacecraft spied mini solar flares, surface explosions some million times smaller than typical solar flares erupting off the Sun.

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