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UKIDSS release DR6 - Data Release 6 - October 13th 2009.

http://surveys.roe.ac.uk/wsa/
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August 18th 2007

Small Telescope Asterism Roster
Called a "wonderful group of asterisms"

http://www.ssoastro.org/STAR_List.htm

I don't agree!


August 29th 2007
Magnitude conversion formulae

http://www.aerith.net/astro/color_conversion.html
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Post #2024 Ed Wiley wrote

"The idea that the WDS should take only measures from peer-reviewed journals is
perfectly reasonable. After all, for all its uses, the WDS is a secondary
source, not a primary source. The idea that new discoveries should be vetted
through peer-reviewed journals is perfectly reasonable."

But this is not happening! There are hundreds, if not thousands, of recent new entries by amateurs astronomers accepted into WDS via "private communication"
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July 9th 2007
Taking a star off my observing list is a bit like saying goodbye to old friend at the airport when you know that you will not be seeing them again. From time to time you wonder what has happened to them but you soon hardly give them a thought.

July 21st 2007
Of course it nice having a group of friends that share your views on a topic. When running any sort of campaign having supporters is pretty close to vital if you don't want to be seen as a crank or extremist. For example in Daventry, Claire and I were fairly central in the successful campaign against a planning application involving a local playing field.

When it becomes more difficult is when your supporters are scattered around the world or when your supporters don't all agree on the best way to approach the issue.It gets even worse when you have supporters you don't know about who highjack the issue. You have long since moved on only to find that the campaign has developed a momentum of its own and that you are perceived as being in charge of people you actually have zero control over.
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Martin Nicholson's SDSS Spectrum Project
http://www.martin-nicholson.info/spectrum/spectrum.htm
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June 20 2007 - Astronomical discoveries - quality and quantity of supporting evidence

It seems to me that some people are making claims about "new" objects found on the DSS plates without any real scientific proof.Any such claims need to be backed up with hard evidence that the object is what it claims to be and that it is indeed new. Any published list or catalogue that contains "fully reseached and proved beyond any real doubt" objects mixed in with "no proof offered" objects will cause nothing but problems for all concerned.


June 26 2007 - Identifying unusual objects in the Sloan Digital Sky Survey (SDSS)

Carbon stars, Cataclysmic Variables (CVs), Blue Horizontal Branch (BHB) stars and RR Lyr stars should be identifiable on the basis of SDSS photometry alone. (The Recognition of Unusual Objects in the Sloan Digital Sky Survey Color System Kevin Krisciunas, Bruce Margon, and Paula Szkody)Excluding outliers

Carbon stars
u-g between 1.9 and 3.9
g-r between 0.75 and 1.4
r-i between 0.2 and 0.9
i-z between 0.25 and 0.6

Cv's
u-g between -0.2 and +0.2
g-r between -0.25 and +0.05
r-i between -0.2 and 0
i-z between -0.2 and 0

BHB
r-i between -0.25 and 0.2
g-r between -0.2 and 0.1

RR LYR
r-i between 0 and 0.25
g-r between 0.05 to 0.35

Stangely there is another source (Faint High-Latitude Carbon Stars Discovered by the Sloan Digital Sky Survey: An Initial Catalog) that gives rather different results for carbon stars with the vast majority having
u-g(1 to 4) and
g-r(0.9 to 2) and
r-i(0.1 to 0.7) and
i-z(0to 0.4)

NB 15.6 < r < 20.8 range

There is also a block of F/G Carbon stars around
u-g(0.9 to 1.2) and
g-r(0.2 to 0.5) and
r-i(0.08 to 0.22)
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