LAUREL, Md. — NASA’s New Horizons spacecraft carried out a flyby of Pluto July 14, collecting images and other data about the distant dwarf planet and its moons that it will spend more than a year returning to Earth.

Signals from the spacecraft arrived at NASA’s Deep Space Network as planned at 8:52:37 p.m. Eastern time July 14, thirteen hours after the spacecraft made its closest approach to the world. Initial results indicated the spacecraft was in good health and experienced no problems during the flyby.

“We have a healthy spacecraft, we’ve recorded data of the Pluto system, and we’re outbound from Pluto,” Alice Bowman, New Horizons mission operations manager, said after polling mission controllers about the telemetry the spacecraft returned.

New Horizons came within about 12,500 kilometers above the surface of Pluto at 7:49 am. Eastern July 14. The spacecraft was out of contact with the Earth during the flyby to focus on science observations. Those activities, as well as a travel time for radio signals of four and a half hours at Pluto’s distance from the Earth, resulted in the 13-hour gap between the flyby and the arrival of the first signal.

That initial post-flyby signal contains only spacecraft telemetry. Project scientists said July 14 that the first set of data collected during the flyby, including some high-resolution images of Pluto and its largest moon, Charon, will be transmitted early July 15.

“We have a pass starting tomorrow morning that will run for several hours,” Alan Stern, principal investigator for New Horizons, said at a briefing July 14 after New Horizons contacted Earth. “There’s going to be quite a waterfall of data for us tomorrow morning.”

The New Horizons team at the Mission Operations Center celebrates after receiving word the spacecraft had contacted Earth and was in good health. Credit: NASA TV
The New Horizons team at the Mission Operations Center celebrates after receiving word the spacecraft had contacted Earth and was in good health. Credit: NASA TV

Earlier in the day, scientists discussed some results that came from observations returned by the spacecraft July 13. That included one image of Pluto sharper than any the spacecraft had previously taken, but which would be overtaken in quality by those collected during the July 14 flyby.

Those observations, which revealed a bright heart-shaped feature on part of the planet along with complex bands of darker materials, are already changing scientists’ perceptions about Pluto.

“Up until yesterday, our best analog for Pluto was Triton, which is Neptune’s large moon,” said John Spencer, a New Horizons science team member with the Southwest Research Institute, during a July 14 briefing about a new Pluto image. “But Triton looks nothing like this.”

Scientists will require some patience to analyze the data New Horizons collected. Some initial high-priority data from the spacecraft’s various instruments will be transmitted down through the end of July, Stern said July 14. However, it will take up to 16 months to download all of the data New Horizons collected during the flyby, because of the spacecraft’s average data rate of two kilobits per second.

“If you think it was big today, wait until tomorrow and the next day,” said NASA Associate Administrator for Science John Grunsfeld. “This is really just the beginning. This is the equivalent of the Curiosity rover landing. It’s the beginning of the mission.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...