The Goldstone radar signal was transmitted toward the asteroid, and the Green Bank Telescope received the radar echoes. “The technique, referred to as a biostatic observation, dramatically improves the amount of detail that can be seen in radar images”, NASA explains.

The new views obtained with the technique show features as small as about 25 feet (7.5 meters) wide.

The individual images used in the movie were generated from data collected on July 25. The object is about 1.2 miles long, making it fairly large for a near-Earth asteroid. After collecting all the images of the flyby, the researchers compiled them to make a video which lasted for seven hours, 40 minutes.

Two radio telescopes were directed towards the asteroid as it zipped by in order to capture radio signals and fine-tuned images of 1999 JD6. The asteroid is between 660 – 980 feet (200 – 300 meters) in diameter.

Scientists wanted to record this rare event because the space peanut won’t be this close to Earth until 2054.

1999 JD6 will be 4.5 million close to the Earth in 2054, NASA has concluded.

A strangely peanut shaped asteroid discovered in 1999 passed by Earth on July 25, 2015, in the closest pass-by in more than a century. They weren’t able to measure its size, but they got information of its physical properties and trajectory. The image you’re seeing here is a time lapse that compresses a period of seven and a half hours.

The funny-shaped area rocks was in fact noticed via the Lowell Observatory Near is that Earth is that Object Search, from Flagstaff, Arizona, on May 12, 1999. Radar measurements of asteroid distances and velocities often enable computation of asteroid orbits much further into the future than would be possible otherwise.

The discovery was made by a team of astronomers at Kent University who found that different parts of a near-Earth asteroid – called Itokawa – have different densities.

A similar space object is now being studied by space experts at the European Space Agency.

The orbit of asteroid 1999 JD6 swings past Earth, Venus and Mercury.