The United States has taken some significant steps into the final frontier during its first 250 years.The nation has put people on the moon, helped build and operate a long-running space station in low Earth orbit (LEO) and sent fleets of robotic explorers to many corners of the solar system — and even beyond it, into interstellar space. All of this work has been done relatively recently, as the space age didn't dawn until 1957; when the U.S. wa…
From the first step on the Moon to the probes that have reached the interstellar space, the United States has redefined cosmic exploration over the last decades. 250 years since the Declaration of Independence, the United States...