Name: ScienceCasts:訪問冥王星 (ScienceCasts: Visit To Pluto)
Uploaded: 2021-01-14T04:49:34.000Z
Duration: 2 min 45 s
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Paying a Visit to Pluto - Presented by Science at NASA.

At this very moment one of the fastest spacecraft ever

launched, NASA's New Horizons, is hurtling through the void

Launched in 2006, it has been in flight longer than some

missions last, and still has four more years of travel to go.

New Horizons is headed for the lonely world of Pluto on the

Although astronomers now call Pluto a dwarf planet, "it's

actually a large place, about 5,000 miles around at the

equator," says Alan Stern, principal investigator for the mission.

Indeed, no spacecraft has ever visited Pluto or any dwarf

"This is a whole new class of worlds," says Stern.

"To understand the solar system, we need to understand

Pluto is a resident of the Kuiper Belt, a vast region

Stern believes "the Kuiper Belt contains a thousand dwarf

Dwarf planets are, in fact, the most numerous class of

planets in the solar system, and probably in the whole universe."

For one thing, Stern wonders, what are the molasses-colored

patches on Pluto's surface seen by the Hubble Space Telescope?

Some scientists think they could be deposits of primordial

"New Horizon's spectrometers will help us identify the

We expect to find something pretty interesting."

Hubble recently contributed more intrigue by spotting a new

moon circling Pluto - bringing the total to four.

Composite Hubble images of Pluto now resemble a miniature

New Horizons will hunt for even more moons as it approaches

To aid in its investigations, New Horizons is carrying one

of the largest and highest resolution interplanetary

It's called LORRI, short for Long-Range Reconnaissance Imager.

"At closest approach to Pluto, LORRI can resolve details

If we flew this instrument over Earth at the same altitude

as we plan to fly over Pluto, we would see individual

Some say we could see those surface deposits of organic material.

Stern says simply, "There could be all kinds of surprises!

It's a first exploration of a new kind of planet."

New Horizons is scheduled to reach Pluto in 2015.

For mission updates, please visit science.nasa.gov.