UB 313: Larger than Pluto

[jtheywood]

The sun looks awfully large in this drawing. I believe it would look more like a bright star than a disk at this distance.

[barakn]

The entire night side of the "planet" is brightly and evenly backlit, which is hard to explain given the size and position of the moon. As noted the sun is too large, but even stranger is the fact that the sun and moon have the same apparent diameter, as if they were airbrushed using the same circular mask (artistic laziness?). The terminator of the planet has too soft a gradient, as if light was refracted and scattered by an invisible atmosphere (there shouldn't be an atmosphere, invisible or not). The position of the terminator on the moon seems to indicate the light source is slightly above and/or to the right of the actual position of the sun. It's hard to gauge the size of the moon, but it is certainly <1/10 the diameter of the planet, and thus is too perfect a sphere, considering its size is roughly that of the irregularly shaped asteroids Juno and Metis.

[makc]

The entire night side of the "planet" is brightly and evenly backlit

It links to earlier APOD, that has spawned very same question. any way, there was 3 pages of discussion, thought you might want to check it out. Edit: here's how it ended, to save you some time:

At 100AU from Sun, the planet receives 1/10000 of the sunlight intensity Earth does. By comparison, the Sun's apparent magnitude on Earth is -26.7 and full Moon's -12.6, therefore we have by the definition of magnitude that Sun is 100^(26.7-12.6)/5) = 437000 times as bright as the full Moon. So an object at 100AU is 43.7 times brighter than Earth in full Moon's light, and as humans can see quite well (even colors) in good direct moonlight they would see the object fairly well lit with eyes adapted to dark.

With long enough exposures, it might even be possible to photograph the dark side in just starlight (even better if the object is illuminated by its own moon too) - though not in the same picture with the sunlit side.

[thomasm@cadence.com]

I too remember reading that from Pluto, the sun would look like a brighter than normal star. While its energy output would be much greater, it would still appear as a pin-point of light. I was surprised to see this sun depicted as having such a large diameter.

[borealis]

There is another artist view on the web page of Michael Brown, one of the discoverers. Also listed in the APOD description.

The text on that page gives an excellent description of the planet's history. I found the discussion of possible names for the planet, and the controversy over what constitutes a planet, interesting.

[orin stepanek]

Here's another one.

http://news.bbc.co.uk/2/hi/science/nature/2306945.stm

Why complicate things. Maybe they are all planets. Just far out. If Galileo could have seen that far I believe he would have called them planets.

Orin

[fastartceetoo]

This is the least realistic, most misleading artistic rendition that APOD has ever published! How many casual viewers are going to get a completely wrong 'understanding' of the outer regions of the solar system?

I expect more of the moderator than this nonsense.

[kovil]

The angular width of the supposed our sun is grossly over stated for being 7-8 billion miles out, and extremely misleading, and this is one of the worst 'science artworks' in recent memory for misrepresentation.
What could this artist have been thinking? Has he no sense of proportion?
The placement of the moon is also eyewise poor subjectively.

Black holes are a tricky subject, and given much more artistic latitude.
(but also a sore subject for artistic junk science artwork)

[ and the howls from the peanut gallery were deafening !! LOL ]

[makc]

I expect more of the moderator than this nonsense.

Like I'm the one who makes pictures. I would actually use this kind of stuff to make those pictures.

[harry]

Hello Kovil

Have to smile over your response

Stay cool,,,,,,,,,,,,,,,,,,they have to make it look good

[makc]

p.s.: here are required addons.

[orin stepanek]

Here's another one
http://www.gps.caltech.edu/~mbrown/sedna/

I think an alien looking for Sol would be a little confused with the map of 9 objects going around it. Who know how many objects are actually orbiting the sun? Many may be quite large and the distances may be vast.

Orin

[kovil]

Wow Orin,

What a great link !!
And the artwork is very much to my liking for being scientifically relatively correct. It is a bit of a long exposure picture; as the planet back would be really dark! and the sun really small and the dust cloud extremely dim.
3 minute exposure at f8 !

This website page really covers the subject !!
So some of those old 'crackpot' cosmologist theorists may be correct after all !! The Oort Cloud and other Velikovsky-esqe ideas will be shown to have roots in truth as we learn more by succeeding space probe flights.

It gets me to thinking the definition of a planet could be;

Something 1500 Km or 1000 Miles in diameter minimum,
able to hold a minimum of 1psi of atmosphere,
and/or has a gravity field of a certain strength.
And/or has additional bodies orbiting it,
perhaps a size of 25-100 Km minimum size moon.

This would make Mars not qualify on the atmospheric pressure requirement, however it would qualify on the diameter and moon requirement aspects. I'm not sure about the gravity aspect.
Mars is kind of halfway between a planet and a non-planet.

Our Moon would fail on atmosphere,
I'm not sure about the gravity aspect,
but it would qualify on diameter
and if it had a moon of its own of sufficient size,
in the absence of the Earth.

Non-qualifying objects could be called,
planetoids, objects above 500 Km dia;
asteroids, under 100 Km dia;
and some new words not yet coined for the inbetween sizes.

ps. This APOD is a nice picture all in all, although it is more representational of a mars/asteroid belt distance from the sun. The sun is still too large for its represented brightness however. One would have to be planetside with a thick atmosphere to experience this much spectrum dimmage.
And from where this picture is taken or painted the albedo of the Mothership must be 99% to backlight this planetary backside ! LOL


Now if the artist placed the moon on the backside of the planet to backlight it, then he might get away with this !

And remember; "Art, is what you can get away with ! " -- Jean Clyde Mason

[fastartceetoo]

I expect more of the moderator than this nonsense.

Like I'm the one who makes pictures. I would actually use this kind of stuff to make those pictures.

Nobody has said, or even implied, that you *made* the picture, makc. But who *chose* the picture for use in APOD, and was it a *good* choice?
[/list]

[harry]

Thank you marc for the link:

http://www.celestiamotherlode.net/catal ... erbelt.php

That was funny another link was attached,,,,,,,

[makc]

But who *chose* the picture for use in APOD, and was it a *good* choice?

Again, I'm not the one 8)