Pop quiz! Without looking it up because that would be cheating.

What's the difference between a plutoid and a plutino?

Pop quiz! Without looking it up because that would be cheating.

What's the difference between a plutoid and a plutino?

Ya got me on this one, for sure! What's the difference between the two? I gotta know now :)

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A plutoid is a dwarf planet orbiting beyond Neptune. That would include dwarf planets in the Kuiper belt and scattered disk, like Eris. There is some debate about the name, some people call them ice dwarfs.

A plutino is an object with an orbit similar to Pluto's, specifically a 2:3 resonance with Neptune (the body makes 2 orbits around the sun for every 3 orbits Neptune makes). Meaning it is on average about the same distance from the Sun as Pluto. A plutino doesn't have to be a dwarf planet. The biggest known one is Orcus at 750 km diameter.

http://www.ourpluto.org/

VOTING ENDS MIDNIGHT PDT APRIL 24 (7:00 GMT APRIL 25)

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rOZZ
Music
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Still time to vote. 12 hours.
http://www.ourpluto.org/

I thought it was a vote regarding Pluto's status as a planet. I discovered they are voting to name surface features.

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

Everybody has missed the whole point here!!! Sigh.

Everybody but you?
Sigh......

I don't see anything special, Pluto and Charon.


New Horizons Sees Pluto and Charon

This series of New Horizons images of Pluto and its largest moon, Charon, was taken at 13 different times spanning 6.5 days, starting on April 12 and ending on April 18, 2015. During that time, the NASA spacecraft's distance from Pluto decreased from about 69 million miles (111 million kilometers) to 64 million miles (104 million kilometers).

The pictures were taken with the New Horizons Long Range Reconnaissance Imager, or LORRI. Pluto and Charon rotate around a center-of-mass (also called the "barycenter") once every 6.4 Earth days, and these LORRI images capture one complete rotation of the system.



http://www.nasa.gov/image-feature/new-horizons-sees-pluto-and-charon

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Beautiful!

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rOZZ
Music
Pictures

I don't see anything special, Pluto and Charon.
Pluto and Charon rotate around a center-of-mass (also called the "barycenter") once every 6.4 Earth days, and these LORRI images capture one complete rotation of the system.

First time I see a moon and a planet rotate around a center-of-mass.
The same when our Moon rotate around the Earth:)

Updated:

Pluto May Have Icy Cap

The latest images from NASA's New Horizons spacecraft show a bright spot near the dwarf planet's pole

Images from NASA’s New Horizons spacecraft suggest that Pluto has a polar cap made of some kind of ice.

The pictures, taken over the past few weeks and released on April 29, show Pluto with its largest moon, Charon. The dwarf planet’s surface is mottled with light and dark patches, each measuring hundreds of kilometres across. But its pole remains bright no matter how Pluto rotates, suggesting that a highly reflective icy cap may exist there. “It’s very suspiciously suggestive,” says Alan Stern, the mission’s principal investigator, who is based at the Southwest Research Institute in Boulder, Colorado.


A bright spot on Pluto (right) could be nitrogen ice. The dwarf planet is shown with its largest moon, Charon.
Credit: NASA

http://www.scientificamerican.com/article/pluto-may-have-icy-cap/

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Update:

NASA’s New Horizons Spots Pluto’s Faintest Known Moons



It’s a complete Pluto family photo – or at least a photo of the family members we’ve already met.

For the first time, NASA’s New Horizons spacecraft has photographed Kerberos and Styx – the smallest and faintest of Pluto’s five known moons. Following the spacecraft’s detection of Pluto’s giant moon Charon in July 2013, and Pluto’s smaller moons Hydra and Nix in July 2014 and January 2015, respectively, New Horizons is now within sight of all the known members of the Pluto system.

“New Horizons is now on the threshold of discovery,” said mission science team member John Spencer, of the Southwest Research Institute in Boulder, Colorado. “If the spacecraft observes any additional moons as we get closer to Pluto, they will be worlds that no one has seen before.”

http://www.nasa.gov/image-feature/nasa-s-new-horizons-spots-pluto-s-faintest-known-moons

Hang on...
If Pluto is not a planet, how can it have moons?
:)

Personally I still think of Pluto as a planet. But just having moons doesn't seem to qualify an object as a planet. Several asteroids have moons and they are not even round.

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.

...so these asteroids with moons should be planets. That makes sense to me

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Bob Smith
Member of Seti PIPPS (Pluto is a Planet Protest Society)
Somewhere in the (un)known Universe?

Pluto and Charon capturing all those moons. They probably have a real strong gravitational pull together acting as a sort of binary system,
since they are so close. There could be more moons, we won't know until the probe gets closer. Odds are Pluto is not boring, planet or not.

People should really read more, before posting... ;)

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non-profit org. Play4Life in Zagreb, Croatia, EU

Pluto and Charon capturing all those moons. They probably have a real strong gravitational pull together acting as a sort of binary system,
since they are so close. There could be more moons, we won't know until the probe gets closer. Odds are Pluto is not boring, planet or not.

I agree Lynn.

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rOZZ
Music
Pictures

A planet (from Ancient Greek ἀστήρ πλανήτης, astēr planētēs, or πλάνης ἀστήρ, plánēs astēr, meaning "wandering star") is an astronomical object orbiting a star or stellar remnant that
* is massive enough to be rounded by its own gravity,
* is not massive enough to cause thermonuclear fusion, and
* has cleared its neighbouring region of planetesimals.

Wandering star?
But planets are not stars. Should astronomers change the name planet as well?

Pluto and Charon capturing all those moons. They probably have a real strong gravitational pull together acting as a sort of binary system,
since they are so close. There could be more moons, we won't know until the probe gets closer. Odds are Pluto is not boring, planet or not.

I agree Lynn.

And i'll second that.

:)

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If at first you don't succeed,
Then skydiving is not for you.