## RE: [guide-user] Magnitude estimation of asteroides

Antonio Alves Sep 20, 2013

Hint:

1: Add an option for user decide what data bases to use
or better
2; option for the user to decide a magnitude differencial to draw these
objects

Will be great for me.
A.Alves

-----Original Message-----
From: guide-user@yahoogroups.com [mailto:guide-user@yahoogroups.com] On
Behalf Of Bill Gray
Sent: Friday, September 20, 2013 1:45 AM
To: guide-user@yahoogroups.com
Subject: Re: [guide-user] Magnitude estimation of asteroides

Hi Denis,

I think I know what's happening here.

Guide now draws comets from three different datasets. (It uses the MPC
list so it can get the very latest comets; a list by Patrick Rocher at the
IMCCE to get most comets since 1995; and an "historical"
list going back to the earliest recorded apparitions of Halley's
Comet.) Imagine the first dataset used has magnitude parameters
indicating that the object is mag 14, and the second puts it at mag 13,
and the third at mag 12.

In that case, if your limiting magnitude is 14 or greater, Guide will
find the object in the first dataset and draw it. It keeps track of what's
already been drawn, so when it comes across the object the second and third
time, it's ignored.

Suppose your limiting magnitude is 13.5. When the object is found in the
first dataset, it's half a magnitude too faint and is skipped.
Then it's found in the second dataset at mag 13, and it's drawn.

And... you see where I'm going here... at limiting mag = 12.5, it's drawn
from the third and last dataset.

I don't have a good answer to this off the top of my head. Let me get
back to you on this one...

-- Bill

On 09/19/2013 07:23 PM, Denis wrote:
> When comets are set in "Data Shown.." on "Auto", decrease the stars
> magnitude to the point where a comet is about to disappear, its
> position changes about a magnitude before the event. After the
> disappearance, increasing the magnitude reverses the process, when the
> comet reappears it will move when magnitude is further increase by one.
>
> If one creates a track as the comet appears and then decreases the
> field which increases magnitude the comet changes position and the
> track become invalid.
>
> We tried on 3 different computer systems and replicated the error with
> more than one comets. Guide version is from 17 June 2013.
>
> This only append when a comet is about to disappear or reappear.
>
> Hope this is clear enough explanation to find a fix.
>
> Denis
>
>