A video by the National Aeronautics and Space Administration (NASA) has revealed the captivating motion of various satellites orbiting the Earth. The animation showns the 19 satellites’ earth-observation paths they move around the planet.

The space agency uses the satellites to monitor conditions on the planet. The video created by the agency’s Scientific Visualization Studio has also included the Cloud-Aerosol Transport System mounted on the International Space Station.

The video includes the four satellites, Aqua, Aura, CloudSat and Calipso. These satellites travel together in the same orbit. Aqua, which was launched in 2002, has been carrying six instruments that observe the earth’s atmosphere, oceans, land, snow covers and vegetation.

The four satellites are part of what the agency calls the ‘A-Train’, and together they carry about 15 different instruments that are used by NASA to study rainfall and aerosols in the air. The satellites have got their name because they cross over the equator each day at 1:30 pm. In ‘A-Train’, ‘A’ stand for ‘afternoon’.

The most recent addition to the set of satellites is Soil Moisture Active-Passive (SMAP), which was launched in January to measure soil moisture and to provide some other data. There is another satellite, Jason 2, in the video. The international earth observation satellite was launched in 2008 as joint effort among NASA, two European agencies and National Oceanic and Atmospheric Administration (NOAA). The satellite was launched to provide information on sea surface heights.

The latest animation was produced by Greg Shirah, lead animator of the space agency and Goddard Space Flight Center; and Ernie Wright and Kel Elkins. Both of them are animators for Universities Space Research Association. According to reports, the new video is an update of a similar video that was made in August 2014, with Shirah as the lead animator.