New Horizons Reveals Dwarf Planet’s Exact Size — NASA Probe Pluto

That’s 10 to 25 kilometers larger than previously estimated.

Scientists suspect Pluto, Charon and their four small moons, all discovered in Hubble images after New Horizons launched, formed after an ancient collision of two icy bodies. New Horizons is traveling about more than 30,000 miles per hour relative to Pluto, roughly 20 times the speed of a rifle bullet.

Overall, mangers figure there is a 1-in-10,000 chance that a debris hit will destroy the spacecraft as it nears or passes Pluto.

Every hour-now revealing new details to what had been the solar system’s most mysterious world.

NASA will release information to the public as it comes in, including what Binzel called up-close and detailed images of individual regions of Pluto’s surface and its moons. For eight years of its cruise towards Pluto, the spacecraft had annual checkouts of spacecraft and instruments, instrument calibration, trajectory corrections and rehearsals for its Pluto encounter.

New Horizons offers all the whiz-bang of many NASA missions; even more given the distances involved. The energy there Tuesday was described as electric.

Glen Fountain, the New Horizons project manager, has advised his staff to enjoy themselves while completing their task.

Three new discoveries were revealed Monday, a tantalizing sneak preview as the countdown to closest approach reached the 21-hour mark. In 1991, no one had yet launched a vessel to Pluto.

Already, the pioneering NASA mission has confirmed the existence of a polar ice cap on Pluto, and found nitrogen escaping from Pluto’s atmosphere.

Pluto’s size has been somewhat of a mystery because the planet’s atmosphere makes it somewhat blurry against the light of background stars, which are used as measurement tools.

As for pictures, the resolution is going to increase dramatically.

New Horizons continues to downlink data on approach to Pluto.

The New Horizons spacecraft is the size of a baby grand piano with a salad bowl – the dish antenna – on top.

NASA/Eyes on the Solar System The flyby will happen at 7:49 a.m. EDT on July 14.

As Stern puts it, “The data is going to start raining down from the sky”.

Pluto is smaller than the Earth’s moon and orbits in a different fashion than many other planets. First, she is a member of the New Horizons Kuiper Belt Object Search Team.

And as for Pluto’s demotion from planet status by astronomers, Stern defends the little guy, citing the fact that “it has all the attributes of other planet. We are excited to finally lay this question to rest”, said mission scientist Bill McKinnon, Washington University, St. Louis.