Reference Star Finder

[Francois Teyssier]

Here's a new version of Reference Star Finder

http://www.astronomie-amateur.fr/Docume ... inder.xlsm

1. Following suggestions (OHP 2015),
- the Miles data base (stars A and B) is added
- computation of altitude (the latitude and longitude of the site must be in decimal format)

2. I added a page "Trajectoire"
With the coordinates of the target, the begining time and duration for target and reference, the altitudes (and azimuth) are computed and drawn in a graph.
Of course, the coordinates of Index page must be (approximativly) the same.
By clicking on the reference list, you choose your reference star
If Alerte is on, messages will comment the reference star (difference of altitudes, interstellar extinction)
Note : correction for precession is not (yet) computed

Please, inform me for bugs

François Teyssier

[Jacques Montier]

Superbe travail François !
En ce qui concerne le coordonnées du site, sur la feuille de calcul Index, elles sont bien demandées en ° ' " et non en décimales (la transformation en valeurs décimales se ensuite fait automatiquement).
La page Trajectoire me semble bien pratique pour déterminer l'heure optimale d'observation.

Amitiés,

[Paul Luckas]

Very nice - thanks for making this available François.

A related question on IR creation:

I notice that the Miles subset database in ISIS may not contain the actual star chosen from the spreadsheet. In this case, is it simply a matter of choosing a reference in ISIS that has the same spectral type (noting that there often many choices and that there are sometimes very subtle differences in published spectra). Or is there a more preferred (precise) way of reconciling the imaged reference star with one in ISIS' miles database?

I'm curious to know how "carried away" people get when selecting and reconciling stars for IR correction.

Paul

[Robin Leadbeater]

Hi Paul,

Where possible I measure an actual MILES star as the spectrum should exactly match the one in the MILES database. The other stars in Francois spreadsheet are just a selection of main sequence A and B stars with low interstellar extinction. They are expected to have typical spectra for that spectral type but we cannot be sure as we do not have actual spectra for them. This means when using these you need to be aware that they may not give an exactly correct result. (Normally these are used with generic spectra for that class eg from the Pickles library)

It would be a useful project to take spectra of Francois' A/B stars under photometric conditions using MILES stars as reference so we can have a set of reliable spectra for them rather than using the generic Pickles spectra.

Robin