Starship Asterisk*

Is it possible for any objects further than Pluto to be bigger?

And does anyone know if the planet have any moons?

EDIT: July 31 APOD

It may be possible, but there are many ice/rock object orbiting the sun in the outer reaches of the solar system. There was a discussion a while back about whether Pluto should actually be called a planet; such objects were talked about in more detail.

Pluto has one satellite, called Charon.

Ah, I hadn't read; you were talking about this. You should post a link w/ info on the subject you start. 8)

At about 100 AUs (Astronomical Units = Sun-Earth distances), it is HIGHLY unlikely that the object in question formed there. Too cold, too thinly spread out amount of stuff to accrete into a large body. Possibly like Pluto, it was formed closer in and was scattered outward by Neptune, but at 100 AU, that seems doubtful - too far out. Possibly something that was captured into orbit.

Re: Planet 10? That assumes Pluto is #9. More on that at other links. Check out http://www.ifa.hawaii.edu/faculty/jewitt/kb.html for more on this.

Re: Having a moon? We're very far from knowing this. Too small, too dark to be obvious. Also, Charon, Pluto's moon and Pluto may not be a planet-moon system, but a "binary" as many other pairs are.

Check out John Davie's book "Beyond Pluto"

Wasn't Quaoar thought to be the 10th planet awhile back? How big the an object have to be to be concidered a planet? Just wondering.
Orin

Size is becoming less and less and determining factor in the argument over what is and what isn't a planet. Some people are arguing that sufficient size (and therefore gravity) that results in a round object, should be considered a planet. But what does shape have to do with it.

Quaaor, Varuna, et al (like many people now feel about Pluto) are just members of larger populations as opposed to single objects in a specific orbit. We used to think some of the larger asteroids were planets until we discovered enough of them in the asteroid belt to "demote" them to members of a larger population.

Up until recently, the same applied to Pluto. But as more of these larger Kuiper Belt Objects are discovered, Pluto may simply be the King of the KBO's although this discovery may dethrone Pluto.

In my humble opinion (maybe I should stick with teeth), Pluto is not a planet. And despite its size, this object should not be considered either.

One thing I haven't read yet is if the orbital mechanics have been worked out, as in does this object know where the solar system's plane is or is it at an that approximates other KBO's.

At 44 degrees of inclination from the plane of the solar system, my vote is Minor Planet - yes. 10th Planet - NO!!

IMHO

At 44 degrees of inclination from the plane of the solar system, my vote is Minor Planet - yes. 10th Planet - NO!!

IMHO

with all the objects in solar orbit; the planets, the asteriods, the moons, the comets; the kuiper belt objects; etc. leads one to believe that would be the normal throughout the galaxi.
Orin

Is it just me, or does anyone else resent the simplistic art of far distant hypothetical planets showing brightly lit night sides? I would be quite happy seeing a painting of a faint crescent and large black shadow against a starry background.

A real planet as well lit as these are would have temps higher than most anything outside the orbit of MARS!

Yeah, it is just me. But I hope someone with better art sense can start publishing realistic planets on APOD and other places.

Just my 1cent (aint worth 2)

No it's not just you (well... maybe, it could be).

Actually, I think APOD sometimes does a disservice with illustrations.

Objects that distant (100 AU) are just not going to be that well lit.

For my two cents 8)

The solar system formed from a disc of material which had gathered in our local Milky Way region.
This disc coalesced further into the sun and planets.

You can call anything orbiting the sun a planet, but once it's found not to made of our system's original materials then it's off the list.
And the corollary is that no matter how far it's orbit is disturbed by whatever forces; it's still a planet if of our original solar disc.

And so what of large captured, orbiting objects? Would they be step-planets?

booky wrote:Is it just me, or does anyone else resent the simplistic art of far distant hypothetical planets showing brightly lit night sides? I would be quite happy seeing a painting of a faint crescent and large black shadow against a starry background.

As per request:
[that image is now gone - makc]

papiamento in his/her sig wrote:Light travels at 186,000 miles per second. Any faster would be dangerous.

planet...layers
...size, no matter
...just big rock
...but then again, i work in a parts department

And how long does light travel from the Sun to the 'Object larger than pluto'? It might well be another star satelite.

Kid wrote:It might well be another star satelite.

Another star's satellite? That would be akin to walking on the street's of New York City and seeing another pedestrian twice as far from the city center as you and pondering whether that person might not really be a local London pedestrian.

No matter the light time from the sun to this object, it is infintesimal compared to the many light years to even the closest stars.

That's right Kid, a lot of people don't realise the distances involved and the relative scales... BB's analogy is a good one.

When you see those pin points of light in the sky you aren't actually seeing the 'physical star', but the star and it's glare. The orbits of any body around that star would be massively contained within that glare....

In short, the distances between the stars are just on a completely different scale than planetary distances. We measure planetary in light-minutes, and even the nearest stars in light-years, so the difference is similar to the difference between minutes and years.....

I found a good reference for the comparative distances/sizes at http://www.nineplanets.org:

Imagine Earth the size of a grape.
The moon would be a foot from the earth.
The sun would be 1.5m in diameter and 150 metres away.
Jupiter would be the size of a large grapefruit and be about 5 city blocks away.
Saturn (an orange!) - 10 blocks.
Uranus and Neptune (lemons) - 20 and 30 blocks.
A Human - the size of an atom.
The nearest star: 40,000 KILOMETERS AWAY.

Vast my friend.... vast.....

do you suppose there are objects; (asteroids); in orbit around two stars??? I don't know much about astronomy but is seems possible.
Orin

Perhaps you've missed it, but there are planets in orbit around three stars.

I was thinking about stars that may be few light years apart. There must be planets out there that may be so far out that they could be caught in orbit around two stars. The large planet in the three star system seems to be more logical for a three star orbit.
Orin

orin stepanek wrote:There must be planets out there that may be so far out that they could be caught in orbit around two stars.

Huh, there you go. Leaving natural question (how could it get SO far out) aside, why do you think there would be such thing as an orbit, in that case? Why an object "caught" in that way can't be later "released", or "hi-jaked" by another star?

I can see that it could be captured by another star.
Orin

Empeda wrote:I found a good reference for the comparative distances/sizes at http://www.nineplanets.org:

Imagine Earth the size of a grape.
The moon would be a foot from the earth.
The sun would be 1.5m in diameter and 150 metres away.
Jupiter would be the size of a large grapefruit and be about 5 city blocks away.
Saturn (an orange!) - 10 blocks.
Uranus and Neptune (lemons) - 20 and 30 blocks.
A Human - the size of an atom.
The nearest star: 40,000 KILOMETERS AWAY.

Vast my friend.... vast.....

This is another way to put it
Speed of light travel and the distance of space

If you could walk at the speed of light, this would be how fast you could travel.
Start at a point on the ground which will represent the center of the sun and mark it, then walk at your regular pace. If you walk for 2.3 seconds, you will reach the outside of the sun. Mark that spot and continue. All distances will be given as time from this point.
Continue walking from the sun for 3 minutes and you reach Mercury, 6 minutes and you reach Venus, 8 ½ minutes to get to Earth (look back to your starting point can you still see it?). 11 minutes from the sun you’ll find Mars. 46 minutes from the sun and you get to Jupiter. 1 hour and 16 minutes from the sun and you arrive at Saturn. 2 hours and 43 minutes from the sun you will find Uranus. 4 hours and 13 minutes of walking will get you to Neptune. 6 hours (360 minutes) of walking will get you to Pluto. How far can you walk in 6 hours? To get to our nearest star, you will have to walk, non stop, for over 4 years. That’s far.

BMAONE23 wrote:look back to your starting point can you still see it?

sure I can, because its lighting is right behind me