This frame from a movie shows the progression of NASA's Near-Earth Object Wide-field Survey Explorer (NEOWISE) investigation for the mission's first two years following its restart in December 2013. Green circles represent near-Earth objects.
These first radar images of 2015 TB145 from the National Science Foundation's 1,000-foot (305-meter) Arecibo Observatory in Puerto Rico, indicate the near-Earth object is spherical in shape and approximately 2,000 feet (600 meters) in diameter.
The asteroid Euphrosyne glides across a field of background stars in this time-lapse view from NASA's WISE spacecraft. Euphrosyne is quite dark in visible light, but glows brightly at infrared wavelengths.
Scientists using two giant, Earth-based radio telescopes bounced radar signals off passing asteroid 2011 UW158 to create images for an animation showing the rocky body's fast rotation. This is a frame from the animation.
This graphic depicts the passage of asteroid 2014 EC past Earth on March 6, 2014. The asteroid's closest approach is a distance equivalent to about one-sixth of the distance between Earth and the moon. The indicated times are in Universal Time.
Asteroid 2014 DX110 Flyby of Earth on March 5, 2014
This graphic depicts the passage of asteroid 2014 DX110 past Earth on March 5, 2014. The asteroid's closest approach was at a distance equivalent to about nine-tenths of the distance between Earth and the moon.
This sequence of radar images of asteroid 2013 ET was obtained on Mar. 10, 2013, by NASA scientists using the 230-foot (70-meter) DSN antenna at Goldstone, CA, when the asteroid was about 693,000 mi (1.1 million km) from Earth.
This set of images from the La Sagra Sky Survey, operated by the Astronomical Observatory of Mallorca in Spain, shows the passage of asteroid 2012 DA14 shortly after its closest, and safe, approach to Earth.