New Delhi: One year ago July 14, 2015, NASA's New Horizons spacecraft made historic flyby of Pluto, giving scientists their first close-up looks at the dwarf planet which has remained mysterious since its discovery in 1930.
New Horizons, moving at speeds that would get it from New York to Los Angeles in about four minutes and three billion miles from Earth, pointing its cameras, spectrometers, and other sensors at the frozen world and its moons, captured hundreds of pictures and other science data that would forever change our view of the outer solar system.
“New Horizons not only completed the era of first reconnaissance of the planets, the mission has intrigued and inspired. Who knew that Pluto would have a heart?” said NASA’s Director of Planetary Science Jim Green. “Even today, New Horizons captures our imagination, rekindles our curiosity, and reminds us of what’s possible.”
As New Horizons' Pluto flyby turned one on July 14, Alan Stern, Principal Investigato of the New Horizons, and a planetary scientist from the Southwest Research Institute, Boulder, Colorado, lists the mission’s most surprising and amazing findings from Pluto so far:
- The complexity of Pluto and its satellites is far beyond what we expected.
- The degree of current activity on Pluto’s surface and the youth of some surfaces on Pluto are simply astounding.
- Pluto’s atmospheric hazes and lower-than-predicted atmospheric escape rate upended all of the pre-flyby models.
- Charon’s enormous equatorial extensional tectonic belt hints at the freezing of a former water ice ocean inside Charon in the distant past. Other evidence found by New Horizons indicates Pluto could well have an internal water-ice ocean today.
- All of Pluto’s moons that can be age-dated by surface craters have the same, ancient age—adding weight to the theory that they were formed together in a single collision between Pluto and another planet in the Kuiper Belt long ago.
- Charon’s dark, red polar cap is unprecedented in the solar system and may be the result of atmospheric gases that escaped Pluto and then accreted on Charon’s surface.
- Pluto’s vast 1,000-kilometer-wide heart-shaped nitrogen glacier (informally called Sputnik Planum) that New Horizons discovered is the largest known glacier in the solar system.
- Pluto shows evidence of vast changes in atmospheric pressure and, possibly, past presence of running or standing liquid volatiles on its surface – something only seen elsewhere on Earth, Mars and Saturn’s moon Titan in our solar system.
- The lack of additional Pluto satellites beyond what was discovered before New Horizons was unexpected.
- Pluto’s atmosphere is blue. Who knew?
— NASA (@NASA) July 14, 2016
As per NASA, New Horizons, which made its closest approach to Pluto (about 7,750 miles above the surface), is now nearly 300 million miles beyond Pluto, speeding to its next destination deeper into the Kuiper Belt. Recently, the US space agency officially approved an extended mission for New Horizons, allowing the probe to fly by a small object called 2014 MU69 on January 1, 2019.
NASA says about 80 percent of the data stored on the spacecraft’s recorders has been sent to Earth while transmission of the remainder will be complete by October.