Will Pluto be considered a planet again, now that we've seen it?

You are allowed to call it a planet as much as you want.

However, if you write a scientific paper to be published in an international astronomy journal, be ready to explain why you want to call it that way, instead of "dwarf planet".

NASA itself uses the word "planet" often enough when describing Pluto on its web sites, especially during New Horizon's close pass. And no one has put them in jail yet.

In our Solar system, the 8 "planets" were forming at the same time as the Sun, and were pretty well fully formed by the time the Sun "turned on" the fusion reaction at its core.

Pluto (and the Trans-Neptunian Objects) formed after, from all the loose matter (water molecules, dust, grains, leftover gas) that got swept out there by the new-born Sun's light.

Therefore, when we look at theories about the formation of the "planets", Pluto is not covered, because it formed differently and at a later time.

There is still a possibility that something in the data MAY prompt us to revise the decision to "demote" it to a dwarf planet status. But "just having seen it" is not sufficient by itself.

If anything, the images confirm that it is smaller than Earth's Moon (it only has 1/6 the mass of our Moon).

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update:

When it was first discovered, it was thought to be the size of Neptune. Then, with better observations, the estimate was brough down to "size of Earth".

With even better observations, it got down to "size of Moon" and to 1/6 the mass of the Moon.

New Horizon simply increased its size (true - latest estimate) by 85 km.

85 over 2360 is less than 4%.

This is like saying: a village, where we thought there were only 100 people, should now be called a city because a count showed 104 people instead of the estimated 100.

It's still a village.

It is still tiny compared to the major planets, and just because a probe has been sent there changes nothing. It does not fulfil the updated criteria for description as a planet, and NEVER did. What's the big deal ? If YOU want to call it a planet, go ahead. You would be wrong, but who gives a sh** ?

Until the probe arrived, we knew virtually NOTHING about Pluto, apart from the fact that it existed. Any previous "facts" about it were nothing but guesswork. Now we have some reliable information, the previous information is just garbage.

Size isn't everything. All that is required is that it is massive enough to pull itself into a vaguely spherical shape under its own gravity. It is big enough to do that so it passes the mass test.

It needs to independently orbit the Sun and not as a satellite of a larger body - Pluto passes that test too.

It needs to have cleared its orbit. Pluto fails that test so it's a dwarf planet under the current IAU definition of a planet.

No, but maybe if people post enough of the same sh*t about it every day, the poor fella's gonna feel better about it.

I don't think a lump of rock out there cares what bipedal jerks (that have been here for a zillionth of the time it has) that live on another piece of rock call it.

Do your research. Then you'd know what's the deal about it-and hundreds of other rocks out there.

Best wishes!

No. Ceres isn't a planet again just because we've photographed it, why would Pluto be?

In the UK it's always been called a planet. Who cares what these 'official' bodies say?

planet still

there are 20+ life support conditions on earth which has nothing to do with "evolving"

evolution is a theory came alive lately based on similarity than actual observations. in the last 10,000 years, we never heard or saw a 1/2 ape 1/2 man or so

Regardless of if we've seen it or not, it still doesn't meet the new criteria of a planet, as set by the IAU...

No. Also it's smaller than our Moon.

It ain't a planet. Get over it.