NASA's Top 7 Greatest  of all time 

Achievements

1. Explorer 1, the First U.S. Satellite

The satellite rode into space onboard a rocket, and it carried equipment designed to help scientists study the cosmic rays in Earth's orbit.

2. Hubble Telescope, Universe Unveiled

this telescope's made more than 1.5 million astronomical observations and looked at over 40,000 different space objects 

3. Chandra X-ray Observatory

In 1999, NASA launched what was for many years the most sensitive X-ray telescope ever built. This contraption could see things no one had ever seen before

7. Juno Spacecraft, a Trip to Jupiter

Juno's mission is to study various aspects of Jupiter, including the planet's gravitational fields and tempestuous atmosphere.

6. Apollo 13

So many things went wrong on Apollo 13, an explosion shut down almost every system necessary it's an engineering miracle that the crew made it home at all

1. A Reusable Spacecraft

 In 1981, the Space Shuttle Columbia lifted off and its maiden mission was successful. NASA had succeeded in creating a reusable spacecraft.

1. Freedom 7 the 1st American in Space

The first American astronaut to orbit the Earth was Alan Shepard, and he left Earth on May 5, 1961 but He wasn't the first human in space