Shop Windows to the Universe

Check out the fun Earth science related bumper stickers in our online store! Express yourself!
Image of Explorer 1 spacecraft.
NASA/JPL

Explorer

Explorer 1, launched on Jan. 31, 1958, was the first U.S. satellite to orbit the Earth. Its successful flight made the United States the second nation in space, following the Soviets who had launched Sputnik 1 just four months earlier.

Explorer 1 carried several scientific instruments which measured space temperature and the dangers of small meteorites. Its major accomplishment was the discovery of an area of radiation which surrounds the Earth.

Between 1958 and 1981 there were 56 more Explorer spacecrafts to reach space. Each was small, relatively inexpensive, and carried out a variety of scientfific missions.


Shop Windows to the Universe Science Store!

Our online store includes books on science education, classroom activities in The Earth Scientist, mineral and fossil specimens, and educational games!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Sputnik

The Soviet Sputnik program consisted of four satellites, three of which reached Earth orbit. Sputnik 1, launched on Oct.4, 1957, became the first artificial satellite to successfully orbit the Earth. It...more

The Discovery of the Radiation Belts

In 1957, Russia launched Sputnik 1, the first spacecraft to ever be launched. Americans wanted to send up a satellite too. They sent up Explorer I. Even though this was America's first satellite, Explorer...more

Radiation Belts

You may have seen a spider web catch bugs in it. Well, the Earth's magnetic field is kind of like a spider's web. It catches particles (protons and electrons) in it. The Earth's magnetic field catches...more

Hubble Space Telescope

The Hubble Space Telescope (HST) is really neat! It was first launched in 1990, but scientists started building it in the 1970's! We have found all kinds of objects like stars, nebulae and galaxies. The...more

Apollo 11

Apollo 11 was the first mission that landed a person on the moon. On July 16, 1969, the U. S. rocket Saturn 5 was launched carrying the lunar landing module Eagle. The Eagle was released and it reached...more

Apollo 12

Apollo 12 was launched on Nov. 14, 1969 and arrived at the Moon three days later. Astronauts Charles Conrad and Alan Bean descended to its surface, while Richard Gordon remained in lunar orbit aboard the...more

Apollo 15

Apollo 15 marked the start of a new series of missions from the Apollo space program, each capable of exploring more lunar terrain than ever before. Launched on July 26, 1971, Apollo 15 reached the Moon...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF