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Re: Planet X: Viewing WHEN?


In Article: <[email protected]> Jeff wrote:
> Good question, though I figure you made a typing mistake 
> when you say the sun rises at 4:13 am, especially if you get
> up at 4:30 and you do NOT see the sun!  :)  It's currently 
> rising around 5:17am for your area.

Oops!  Guess I pulled an Open Minded and forgot about DST.  We Sprang forward 
last Spring.  Thanks Jeff!. And I will post on my web site and tell the hords 
of folks writing to me that the TWO HOURS before dawn are light polluted.  I 
guess when I was by intuition telling folks that viewing before this FALL was 
not possible, due to pre-dawn light, I was right.  And Open Minded WRONG to say 
late June, late July, etc.

> As for darkness, you START losing that at around 2:59am, 
> or basically 3:00am.  So after 3am, you skies will start 
> getting brighter.  If your mythical Planet X did exist, it 
> would not be visible (unless it's as bright as Venus or 
> something) since it would rise at around 4:38am. 
> And I wouldn't use M31 as a comparison since it is very 
> large and has it's brightness spread out over a large area.  

So Open Minded is stating that Planet X, viewing characteristics pretty well 
understood from the past year of discussions on sci.astro and the IMAGING in 
infrared last Jan 5th and 19th
(http://www.zetatalk.com/teams/tteam342.htm)
by Open Minded himself in fact, will be VISIBLE in late June, in that thoroughly 
light polluted hour before dawn!

Very interesting.  

In Article: <[email protected]> Open Minded wrote:
> It is true that astronomical dawn (sun 18 degrees down) 
> currently begins for Nancy at about 3AM. ...
> Most naked eye stars are still visible to the naked eye 
> observer at this time and with a telescope all but the 
> faintest telescopic objects will be visible with a small
> telescope.

What do you think you and Pierre-Eric were imaging last January?!?  M31?  Open 
Minded, would you make the statement that M31 is visible, to the naked eye as it 
is during the deep night, those two hours pre-dawn? Jeff stated that M31 is not a 
good comparison, as it is BRIGHT.  You ignored this part of the question altogether.

In Article: <[email protected]> Nancy wrote:
> Put another way, at what point would M31 be visible, or 
> not visible, predawn?  Though magnitude 3.7 one can 
> BARELY see it, no scope required, as it is diffuse.  
> Could you see M31 the hour before dawn? 

And to answer questions re magnitude and size of Planet X this late summer or Fall.
- larger than it was last January, thus amateur scopes can pick 
  it up no observatory scope required
- brighter than it was last January

But for the sake of this discussion, lets fall back to what it was in January, 
when you captured it on an image, Open Minded.  THAT size and magnitude.  You 
could see something slighly brighter and larger than that, during the astronomical dawn?  .