I’m really looking forward to it, but I can’t find any official date. Would it be safe to say that when they are released, I will know without even trying to look?
Even with Hubble, Sedna would only appear as a tiny orange dot. A planet that far away isn’t going to have much angular size. The best pictures of Pluto with Hubble can resolve no more than a few continent sized details with many many pictures superimposed. Sedna is even farther away and smaller.
This article has size and distance comparisons. Sedna is believed to be slightly smaller than Pluto and roughly twice as far, so its apparent size will be less than half that of Pluto. Also much darker.
The article also says:
I’m not too familiar with the Hubble’s operational procedures, but I think that means they have written the proposal to use the Hubble to look at this object and are awaiting the decision. That’s how most observatories work. Observing Sedna isn’t exactly urgent (unlike a comet or supernova), so I don’t expect them to cancel scheduled observations to make room.
Hubble probably will eye Sedna this year. There is too much public intrigue and professional interest to ignore it.
I am intrigued by this planetoid’s reported red colour; I was expecting all the kuiper belt objects to be grey, water ice objects like the smaller moons of Neptune…
but this colour has me beat.
an image of this world created using Celestia;
Several Hubble images of Pluto and Charon. Getting images of Sedna with it will handily settle the question of whether it’s a single body, but that’ll indeed probably be about it.
Cool! Thanks, bonzer!
And now we’re going to lose Hubble just when things are getting so interesting in our neighborhood! Damn damn damn damn.
Why can the telescope get better pictures of very far away objects than it can of the (comparatively) close Sedna?
IANA Astronomer, but the very far away objects are much larger and emit their own light as opposed to reflecting it from the sun.
Simply, the things that Hubble can see tha are very far away are also a whole lot bigger and brighter than Sedna is.
At a distance of 13 billion miles and a diameter of 1100 miles, Sedna will cover about 4.85 X 10[sup]-6[/sup] degrees of sky. That’s 0.017 arcseconds.
The limit of resolution for groundbased scopes (at least those that don’t cheat by using adaptive optics) is about 1 arcsecond. Hubble’s faint object camera (if it’s running) can resolve things down to 0.0072 arcseconds. The camera’s best image of Sedna would thus be 2.36 pixels across. The entire disk of the planetoid would be contained within about 6 square pixels.
We need a bigger telescope in orbit.
And by ‘a whole lot bigger’ we don’t even mean the size of Jupiter - objects of that size around other stars are not visible by Hubble. The only reason we know they exist is because their gravity makes their stars wobble.
Those spectacular hubble images you see from Hubble are MASSIVE. So massive that something on the scale of our entire solar system would be just a tiny dot on the picture. Those big spectacular nebulae we see are light-years across.
There are future telescopes in the works that will be able to image some of these smaller features. They are generally arrays of large telescopes flying in space that use interferometry to get unbelievable large effective apertures. In theory, we could build telescope arrays so big that we could image features on planets around other stars down to a few hundred feet across - actually look at the surface of planets light years away for signs of intelligent life, vegetation, etc.
That scans very nicely after my last sentence Sam
[nitpick]Less than one fourth. Something twice as far away has an apparent size of one-fourth of the other.[/nitpick]