From a recent BBC article:

How do we know it's shiny? Does this have something to do with polarization of light we see from it? I've looked through the press releases, but not seen anything substantiating this statement.

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Maybe Sedna's surface temperature it's like Mars. I mean more than Mars, like 400K - 500K, and it also absorb all visible light reflect red color...

The 2nd reason for Sedna is shiny, maybe there is a nearby star next to it, like 2 - 3 AU away from Sedna.

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We come without a thing and gone without a thing. We need simple life. A cup of teas and a couple of meals per day, that is good enough. And this is my standard of living.

I wonder what they mean by "shiny".

Sedna does have a relatively high albedo - i.e. it reflects more light than most KBOs. They know that because they couldn't detect it with the Spitzer Telescope in the infra-red, which means it is very cold, which means it doesn't absorb as much light as other KBOs. Since it ain't absorbing it, it must be reflecting it.

Maybe the BBC thinks "high albedo" means "shiny".

That could be it. It happens once in a while that BBC journalists use some tertiary definition of a word, and even if the story becomes misleading, they stand by their choice of word.

I remember a story a few weeks ago in which they described the comet that Rosetta was going to as 'Mountainous'. I questioned the writer about it, and he said the word was legit because the comet was the size of a mountain, and there for like a mountain, which made it mountainous.

For those in doubt, we have no reason to think that this object has mountains on it.

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Hi
Just a thought, if Sedna is " shiny " then it might be smaller than was previously thought..... Still the big question is is it a planet ??

Mord

Actually mordredd its albedo was taken into account when they determined it's mass. If anything they went to the conservative side, so it may be even bigger.

Ok, leads to a poll type question. If it turns out to be bigger than Pluto, do we call it a planet? Or do we call Pluto a Kuiper belt object?

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Let every man judge according to his own standards, by what he has himself read, not by what others tell him. ~Albert Einstein~

That's not going to be a problem. The discoverers say it's at most 1800 km in diameter, about 3/4 the size of Pluto.

From their own Sedna Page:

"In collaboration with Frank Bertoldi at the MPIfR Bonn, we used the 30 meter diameter IRAM telscope, and in collaboration with John Stansberry at the University of Arizona and Bill Reach at the Spitzer Science Certer, we used the Spitzer Space Telescope. Sedna was too small to be detected in either. This tells us that Sedna is at most about 1800 km in diameter: about halfway in size between Pluto and the largest known Kuiper belt object Quaoar."

Even though 1800 km is the upper limit on its size, Brown claims they have other evidence that means it must be close to that upper limit. Which is a little strange, because on Trujillo's page that leaked yesterday and has disappeared since, he said it was between 1/3 and 2/3 the size of Pluto (Trujillo is Brown's partner in this discovery).

Anyway, it's clearly smaller than Pluto.

But if it comes to a vote, I'd go with Pluto being demoted to KBO. That's what happened to Ceres, which was originally called a planet, untill all those other silly asteroids came along. I'm sure that's what's eventually going to happen with Pluto too.

ok lets think for 2 seconds

Pluto:
Equatorial radius (km) 1,160
Equatorial radius (Earth = 1) 1.8188e-01

Charon:
Equatorial radius (km) 635
Equatorial radius (Earth = 1) 9.9561e-02
(thanks to http://www.ias.fr/cdp/solar/eng/pluto.htm)

if radius is half of diameter
Pluto is 2,320 km
Charon is 1270 km
and Sedna 1800 km (upper limmit)
thats only 500 kilos now this may be small but the astronomers of today realy have to set a limit i think the limit should be right 2000 (meaning pluto bearly makes it in.

But then u get the question of what if u have a planet liek sedna(is sedna gaseous of solid? im assumin solid) its solid and there is say animals like little bugs on it.
Not humans but its 'LIFE' so how can we not consider this floating rock a planet! are we gonna kall a planet that supports life a planet or a plaentoid.

this is from dictionary.com

plan·et ( P ) Pronunciation Key (plnt)
n.
A nonluminous celestial body larger than an asteroid or comet, illuminated by light from a star, such as the sun, around which it revolves. In the solar system there are nine known planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto.
One of the seven celestial bodies, Mercury, Venus, the moon, the sun, Mars, Jupiter, and Saturn, visible to the naked eye and thought by ancient astronomers to revolve in the heavens about a fixed Earth and among fixed stars.
One of the seven revolving astrological celestial bodies that in conjunction with the stars are believed to influence human affairs and personalities.


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[Middle English, from Old French planete, from Late Latin planta, from Greek plants, variant of plans, plant-, from plansthai, to wander. See pel-2 in Indo-European Roots.]

from a latin dictionary

planta -ae f. (1) [a green twig , cutting, graft; a plant]. (2) [the sole of the foot].

WHAT????

of course plants and plans both are not in any greek dictionarys i found

HMMMMM

So many questions that will never be answered in our lifetime :angry: ....why do i bother <_<

I need a little more than 2 seconds here.

I just steped off of planet earth about a month ago and have been focusing primarily on the moon and mars. About a week ago I started exploring Venus and Saturn. So, relatively speaking, I know nothing. When searching I found sites that referenced numerical data similar to Nerdman20 and was kicking myself in the rear for not being able to read it. I could probably figure it out but my patience is a little thin at the moment on an account of a bunch of stuff coming together at school. If you guys could fill in for me it'd make it alot easier for me.

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I am forever striving for increased perfection of my understanding of this world we live in. My quest through life is knowledge and I am but a child on this ubiquitous journey, as are we all. Knowledge, like the universe, is infinite.

Ok, Now I'm angry.

And I tend to look for the best in things BUT

Object discovered on edge of galaxy

Now MSN has provided a stunning example of an exagerated headline. At least that don't call it a planet.

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Thats actually funny, in a sad sort of way. Makes you shake your head hey?

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All civilizations become either spacefaring or extinct.~ Carl Sagan ~

Humanity must rise above the Earth, to the top of the atmosphere and beyond, for only then will we fully understand the world in which we live.~Socrates, 500 B.C. ~

Let every man judge according to his own standards, by what he has himself read, not by what others tell him. ~Albert Einstein~

My head is shaking so much it has almost fallen off, and my metal implants in my jaw is generating a bit of an induced magnetic field....:wacko:

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Damien,
International Baccalaureate Physics teacher
Optics, Photogrammetry and Remote Sensing Instrumentation Major
Admin: Pacific Science and Art