Spaceflight Insider

New Horizons conducts historic Pluto flyby

New Horizons Pluto Flyby Media Briefing.

NASA Senior Public Affairs Officer Dwayne Brown, standing left, closes a New Horizons media briefing as NASA Associate Administrator for the Science Mission Directorate John Grunsfeld, seated left, New Horizons Principal Investigator Alan Stern of Southwest Research Institute (SwRI), Boulder, CO., center, and New Horizons Mission Operations Manager Johns Hopkins University Applied Physics Laboratory (APL) Alice Bowman wave the American flag in response to receiving the "phone home" signal from the New Horizons spacecraft confirming that it had successfully passed through the Plutonian system and completed its programmed mission to collect the required data. The media event was held on Tuesday, July 14, 2015, at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland. Photo Credit: NASA/Bill Ingalls

At 7:49 a.m. EDT (12:49 GMT), July 14, 2015, NASA’s New Horizons spacecraft made its closest approach to the Pluto system, flying within 7,750 miles (12,472 km) of Pluto’s surface.

At the Johns Hopkins University Applied Physics Lab in Laurel, Maryland, more than a thousand people, including APL employees, mission team members, guests, and media took part in a New Year’s Eve-style countdown to the exact moment of closest approach – cheering and waving flags when the moment arrived.

In a live media event that began at 8 a.m. EDT, the mission team released the last image that was taken of Pluto before closest approach – a vivid picture prominently featuring the heart-shaped bright area on the encounter side.

Pluto imaged by LORRI aboard NASA’s New Horizons spacecraft, taken on July 13, 2015, when the spacecraft was 768,000 kilometers from the surface.

Pluto imaged by LORRI aboard NASA’s New Horizons spacecraft, taken on July 13, 2015, when the spacecraft was 476,000 miles (768,000 km) from the surface. (Click to enlarge.) Photo Credits: NASA/JHU-APL/SwRI

Some described the image as Pluto’s “love note” to Earth. It was taken using the Long Range Reconnaissance Imager (LORRI) on Monday, July 13, at approximately 4 p.m. EDT when the spacecraft was about 476,000 miles (768,000 km) from Pluto’s surface. Pluto filled nearly the whole frame in the image.

From this picture, scientists can tell that certain regions of Pluto, those heavily peppered with craters, have ancient surfaces; whereas others, including the heart-shaped region, appear to be young – with no craters at all. In some sections of the image, there are craters that look partly destroyed, possibly by erosion. The dark “whale” area has many craters near the whale’s “head”.

“My prediction was that we would find something wonderful, and we did. This is proof that good things really do come in small packages, principal investigator,” Alan Stern said.

The mission team also created a false color image of Pluto and Charon in exaggerated colors to highlight the diversity of features on both worlds.

This July 13, 2015, image of Pluto and Charon is presented in false colors to make differences in surface material and features easy to see.

Pluto and Charon in false color showing compositional diversity. (Click to enlarge) Image Credits: NASA/JHU-APL/SwRI

In an interview with Spaceflight Insider, Stern discussed his first impressions of New Horizons findings, describing Pluto as a “very complicated” world. When asked to speculate about the possibility of subsurface oceans, he emphasized higher resolution data is needed before the existence of such oceans could be confirmed.

The same is true for the question of whether Pluto’s atmosphere never completely freezes out, even during the farthest point of its orbit, as proposed in a recent study. New Horizons’ data will eventually answer that question, Stern said.

At Mission Control, Stern also said that New Horizons team members had a special picture-taking ceremony yesterday at midnight Universal Time when the date turned to July 14. Then they went home, after the spacecraft went silent, for some much-needed rest.

“The day of year changed to day 195. For 15 years, we’ve known that 2015 day 195 is the day. Then the clock changed, and even though here, it was in the afternoon, it was, it’s encounter day.”

Data that will determine whether Pluto and Charon share an atmosphere was acquired today by the New Horizons spacecraft after it had stopped communicating with Earth so that it could focus solely on observing Pluto and its system of moons.

Stern said that most of the Charon data will come back within several weeks after the Pluto data. Also, most of the data about the four mysterious dark spots on Pluto’s far side is still on the spacecraft. That includes both images and spectroscopy.

“We did show an image at the best resolution of the far side,” he noted.

New Horizons’ instruments will continue to image the Pluto system over the next few weeks – even as the spacecraft flies away from the dwarf planet.

Mission results will not be discussed at next month’s IAU General Assembly, Stern said. Instead, the mission team will debut New Horizons at the Division of Planetary Sciences meeting in November.

Finally, Professor Stephen Hawking congratulates the NASA New Horizons team…

Video courtesy of NASA New Horizons



Laurel Kornfeld is an amateur astronomer and freelance writer from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass College, Rutgers University, and earned a Graduate Certificate of Science from Swinburne University’s Astronomy Online program. Her writings have been published online in The Atlantic, Astronomy magazine’s guest blog section, the UK Space Conference, the 2009 IAU General Assembly newspaper, The Space Reporter, and newsletters of various astronomy clubs. She is a member of the Cranford, NJ-based Amateur Astronomers, Inc. Especially interested in the outer solar system, Laurel gave a brief presentation at the 2008 Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in Laurel, MD.

Reader Comments

Good article. Wow..this is going to be fun watching the Pluto/Charon system come alive before our eyes. What an amazing mission!

⚠ Commenting Rules

Post Comment

Your email address will not be published. Required fields are marked *