An incorrect color photo of Neptune was made from Voyager 2 images taken through 3 filters. (Image credit: NASA/JPL)
What it is: One of the last pictures of Neptune taken by NASA's Voyager 2 probe
Where it is: 2.8 billion miles (4.5 billion kilometers) from the sun
When it was taken: Aug. 25, 1989
When it was shared: Aug. 19, 2024
Why it's so unique: Only one spacecraft has actually ever gone to the 8th and most remote world from the sun.
On Aug. 25, 1989, NASA's Voyager 2 spacecraft took the first-ever close-up pictures of Neptune. This one– amongst the last full-disk images taken before the probe ended its “Grand Tour” of the worlds– turned into one of the most renowned. It exposed Neptune as a deep azure blue, which colored the general public's understanding of the world for years. (That is, till a brand-new treatment of Voyager 2's images previously this year exposed Neptune's real color to be a much lighter blue green.)
Voyager 2's initial images were taken in incorrect color utilizing filters– a basic method utilized by planetary astronomers. In this case, blue and green filters were utilized along with one that passes light at a wavelength taken in by methane gas. According to researchers, hydrogen and helium control Neptune's environment, however methane offers it its blue look by soaking up traffic signal. The filters make methane appearance dark blue in this image, however they likewise expose a semitransparent haze layer throughout the world. The bright-red edge around Neptune is brought on by the haze scattering sunshine at greater elevations, above the majority of the methane.
Get the world's most interesting discoveries provided directly to your inbox.
Related: Uranus and Neptune aren't made from what we believed, brand-new research study hints
Voyager 2 took this shot nearly specifically 12 years after it introduced on a Titan-Centaur rocket from Cape Canaveral, Florida. Having actually gone to Jupiter in 1979, Saturn in 1981 and Uranus in 1985, Voyager's closest technique to Neptune began Aug. 25, 1989. Throughout the flyby, Voyager likewise went to 2 of Neptune's moons, Triton and Nereid, and found 6 brand-new moons and 4 rings.
Due to the fact that Neptune has to do with 30 times further from the sun than Earth is, it gets just a faction of a percent of Earth's sunshine, indicating Voyager 2 needed to take long-exposure images. Engineers fired the fast-moving spacecraft's thrusters to have it turn so the video camera might stay concentrated.
Voyager 2's images from Neptune were its last, returned as radio signals with 13-watt transmitters– about adequate power to run a fridge light bulb, according to NASA– and took 4 hours to take a trip throughout the planetary system to NASA's Deep Space Network of radio antennae throughout the world.
Neptune was Voyager 2's last stop before it took a trip to the planetary system's edge. The probe went into interstellar area on Nov. 5, 2018. Voyager 2 stays NASA's longest-running objective,
