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Spacing out with stamps and bricks

by Melody M. Bomgardner
June 5, 2017 | A version of this story appeared in Volume 95, Issue 23


Total eclipse of the stamp

Credit: U.S. Postal Service
Credit: U.S. Postal Service

Mooned: The U.S. Postal Service features the sun’s corona and the moon on a single stamp.

On what is sure to be an otherwise bright day on Aug. 21, a shadow will darken the land. Specifically, it will darken a 110-km stripe centered on the town of Lincoln Beach in Oregon at 10:18 AM before moving in a southeasterly direction to Bonneau Beach, S.C., at 2:47 PM.

Die-hard solar eclipse 2017 fans have long ago staked out their viewing spots. And any eclipse laggards can check the National Aeronautics & Space Administration website for detailed maps. Meanwhile the Newscripts gang is preparing by scrounging around the sofa cushions to come up with 49 cents for first class postage.

That’s because Aug. 21 is a Monday, and Newscripts never takes a day off. But we love a good eclipse. Luckily the U.S. Postal Service has come to the rescue with a color-changing stamp to portray and celebrate the event. The stamp, to be released on June 20, features a photo of the sun’s corona, with the sun itself perfectly blocked out by the black disk of the moon.

Not only can you stare directly at this stamp—no funny glasses required—touching the image reveals a photo of the moon in stunning detail. The picture change is thanks to thermochromic ink. Though color-changing ink was made famous by 1970s-era mood rings, this is the first time the Postal Service has featured it on a stamp.

Both photos on the stamp come courtesy of Mr. Eclipse, who also goes by Fred Espenak. Espenak is a retired NASA astrophysicist and, more important in this instance, an amateur astronomer and expert with a camera. The photo featured on the stamp is one he took in Libya in 2006.

“I’m sure the term ‘awe inspiring’ came into being after someone saw a total eclipse,” Espenak gushes. Reflecting on his first eclipse in 1970, he recalls, “There is nothing else that comes close. I thought, ‘This can’t be once in a lifetime; I have to see another.’ ”

And he did. “Since the early 1990s I have been to every total eclipse,” Espenak says. That works out to 27 stakeouts around the world, though seven times his view was blocked by clouds.

While a total solar eclipse is rare, “it’s a real once-in-a-lifetime experience to have your art featured on a stamp,” Espenak says.

Espenak will be in Casper, Wyo., for this year’s eclipse. And he’ll arrive the week before to speak at a big astronomy conference there. He says, “I got the invitation four years in advance.”

Mars brick breakthrough

Credit: Shutterstock/Yu Qiao
Great bricks from Mars dirt: If you come you’ll have to build with them.
Photo of a brick made from simulated Mars dirt and an astronaut.
Credit: Shutterstock/Yu Qiao
Great bricks from Mars dirt: If you come you’ll have to build with them.

Some space enthusiasts are eyeing the moon these days for a different reason: It could be the jumping-off point for a mission to Mars. But visitors who hope to stay awhile will need accommodations.

Mars features zero Airbnbs; there’s not even a Home Depot. So Yu Qiao and team members in the Department of structural engineering at the University of California, San Diego, decided to see if settlers could just use the material at hand.

They used a Martian soil simulant, called Mars-1a, to see how easily they could make a building material. Previous attempts required additives or calcination, which demands extra supplies and energy, respectively.

“The initial idea was to use a small amount of polymer binder to hold the soil grains together,” Qiao says. He was surprised to find that even without additives, mechanically compressing the soil made pretty sturdy bricks.

The red planet’s soil contains nanoparticulate iron oxides and oxyhydroxides, which together form a rind on the outside of basalt particles. When the soil is pressed, the particles bind together. Rather than using mortar to join the bricks, Qiao suggests compacting layer upon layer to make buildings.

Mars colonies would look like adobe villages and not like those networks of cool geodesic domes depicted in most Martian fantasies. But it makes packing for the trip much easier. Newscripts asked Qiao what he’d bring with him instead. “I never thought about this question,” he says. “Usually my wife handles our baggage.”

Melody Bomgardner wrote this week’s column. Please send comments and suggestions to


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