One of the speakers was astronaut Pat Forrester, who says "I've been living in D.C. since I was a little boy. I never miss an opportunity to come in here. I'm always amazed at what we as humans have done in exploration."
The retired Army colonel, a graduate of West Springfield High School, flew on shuttle missions in 2001, 2007 and 2009. According to NASA, he has spent more than 950 hours in space, including four spacewalks. He currently works in NASA's astronaut office.
"There's a misconception out there that the space program's over because we've retired the space shuttle, but we've got a very active space program both with putting humans on the International Space Station, but also as we begin to go beyond low-Earth orbit," Forrester says.
ILC Dover, which has made space suits for NASA spacewalks since 1962, had a display with a suit from the Apollo era and another from today. The company's Bill Ayrey describes a space suit as "like a miniature spaceship" because of all the technology built in.
But the colors of a space suit are important too, he says. "The white color helps keep the suit cooler; you don't want to absorb that heat. And then of course, the gold visor. The visor is actual gold material, and it'll reflect that sunlight away from the suit. … In space, it is extremely bright out there and you need that visor to see what you're doing. And if you're working toward the sun, it helps quite a bit."
In addition to hearing from astronauts and seeing exhibits, kids got the chance to make their own mission patches with stickers and markers, and make comets with aluminum foil, a small foam ball and a lace tail on top of a wooden stick.
In honor of May 4th, the Washington Metropolitan Area LEGO Users Group included some Star Wars-inspired creations among the custom models based on actual spacecraft like the Voyager II and Mars Curiosity rover.
"Those two were actually designed by a real-life former NASA engineer. He worked on the Curiosity rover," says Matthew Bowman, of Silver Spring.
He says the complicated displays involve parts from actual Lego sets compiled into custom designs.
This year and part of next year marks the 40th anniversary of Skylab, the first manned space station. A model of it sits in one of the main exhibit areas, right underneath what was planned to be the second Skylab.
David DeVorkin, the museum's senior curator of history of astronomy and the space sciences, says "Skylab had a purpose. Other than to establish how to live and work in space … they had a whole range of scientific things to do." He says he's most involved with the Apollo telescope mount - which got its name because it was made from used Apollo parts, as was Skylab.
DeVorkin says some of Skylab's key research focused on the sun and solar flares.
"The flares eject enormous amount of material into space, and if it's directed toward us it's called a coronal mass ejection and that's not good."
In 1859, even before cell phones and satellites, it's believed a solar storm led to a major disruption of telegraph service. "In a modern society, we depend on a lot of electronic stuff, and one of these big solar flares could just fry us," DeVorkin says.
The aim of Space Day is to encourage kids to pursue careers in science, technology engineering and math.
Forrester calls his three missions to help build the International Space Station "a great experience, but also a unique opportunity to represent the citizens of our country."
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