Conventions

  • All angles or coordinates are stored internally in radians
  • All angles or coordinates mostly are presented to the user in degrees (sexagesimal format for coordinates, degrees for distances)
  • double must be used as storage
  • dates: use ISO8601 format as external format for presentation, Julian days as internal format.

Use cases

JmmcAsproProjectPlots : sample plots

Observability of a source (or list of sources) for a given interferometer

Inputs User format internal format
Star name anything  
Star coordinate retrieved from NAME with Simabd, or entered by user (Ra,Dec only?) RAJ2000,DEJ2000
Observing site location selection of one supported observatory observatory reference
Date of observation ( or period of time ) like DDMMYYYYHHMM (Modified) Julian Day ( precise up to the second )

Plot outputs: How to represent the observability of a list of star onto multi-telescope?
The observability of star is a series of time intervals where the star is visible from a location at a given date. This serie is telescope/station dependent (since there may be different horizons). Time intervals are segments of a time-line, at each point of which can be attached a list of properties: azimuth, elevation, airmass, atmospheric refraction, distance from sun, moon or another object (down to binary orbits!). The grouping into segments is meaningful. For multi-telescope observability, the observability is the intersection of all observability intervals.

Is the source visible in the sky ?

Is the source over the horizon ?

outputs Internal/User Format
celestial coordinates Internal HA / delta ?? units TBC TBD
over the horizon User boolean

What is the AirMass value ?

GD note: below: nothing to do with airmass. airmass is just proportional to zeta, where zeta is the zenital angle (or more complicated formula if spherical atmosphere). Humidity x airmass give optical absorption. Seeing is proportional to airmass (TBC).
Inputs User format internal format
Seeing choice or value ? TBD
Humidity / Temperature... choice or value ? TBD

outputs Internal/User Format
AirMass User double

What is the best method to get the airmass value?

Where are the sun / moon ?

Inputs User format internal format
twilight constraints angle degrees (ASTRO/NAVAL/CIVIL) double radians

outputs Internal/User Format
sunrise sunset moonrise moonset moonphase moonIllumination User DateTime couples

Est-ce qu'il faut gerer d'autre planetes sources lumineuses ??? Quelles doit etre la precision pour les ephemerides? qq minutes

Is the star still visible given to a shadowing ???

Inputs User format internal format
environment shadowing ( telescopes, mountains, building ....) angle d'obstruction ( de 0 a 90 degres) en fonction de l'azimuth (repere a definir) couples of Altitude / Azimuth points
telescope(s) min elevation angle degree angle radians

What is the formulae of the observability given to the whole previous results?

A-t'on besoin de calculer l'AirMass par station? NON Est-ce que la voute celeste est la meme pour toutes les stations a un meme moment? NON a cause de l'horizon

S'arrete-ton des le premier critere mauvais ou doit on faire un bilan de pertes...( par ex: une mauvaise airmass compensee par un configuration optique avec moins de pertes) Qu"entends-tu par "s'arrêter?"

Comment gere-t'on l'observalité d'une liste d'etoiles? Est simplement la juxtaposition des resultats independants ou y-a t'il des contraintes de gestion par groupe? Prévoir une gestion par groupe, sans l'approfondir. Laisser la liaison entre les membres d'un groupe possible comme dans un dessin où on groupe des éléments graphiques, sans plus.

Modelling of a source from a given interferometer

JmmcAsproTargetModel : dedicated twiki topic

Various informations

Station Coordinates

The software handles station coordinates as described in the OIFITS (see OI_ARRAY table description). The software accepts only the OIFITS values. All conversions to OIFITS values must be done externally.

VLTI configuration

Eso defines the coordinates in an proprietary maner. The right way to get the right informations is to read the data from an AMBER oifits ( may be generated by ASPRO ).

CHARA configuration

Chara expresses the station coordinates in the same format as OIFITS. Use ASPRO values.

Java astronomy libraries

JSkyCalc = Java version of skycalc
AstroLib
URLToBeDefined)?topicparent=Jmmc/Software.JmmcAsproProjectConception;nowysiwyg=0" rel="nofollow" title="PAL projet astrogrid (utilisé par APES et topcat) (this topic does not yet exist; you can create it)">PAL projet astrogrid (utilisé par APES et topcat)

Verifier : conversion coordonnees et ephemeride (au moins soleil et lune)

Various libraries

Various documentation

S'il faut developper une librairie graphique: http://www.siggraph.org/education/materials/HyperVis/percept/visrules.htm

Main ASPRO functionnalities compared to alternates tools

Observability plot

In contrary to APES, ASPRO is not a planetarium (planetarium: has animations/colors, and tries to mimic precisely the visual aspect of the sky).
The main information consist in the observability timestamps of a target of a list of targets i.e. a simple list of time intervals could be enough (like the observation scheduler).
However, beyond this minimal view the user should have details in a pop up or a contextual window (target rise/set, elevation).
The user could add / remove / hide a target that is present in the plot

UV coverage plot

Use the Model Fitting GUI to define & display model parameters and associate a model per target instead of a single model for the current version of ASPRO.
This plot should be displayed when a target is selected on the Observability plot. The UV tracks are ellipse segments. They have the same properties as for the observability time-line: each point can be tagged with an number of properties (in fact, all the properties of OI_VIS and OI_VIS2). Some properties associate 3 telescopes (OI_T3), and thus 3 uv tracks. Leave a possibility to associate more than 3 telescopes (intensity closure associates 4).

Other items

  • APES 'Select a baseline' widget has an interesting interferometer representation but it's less important. An expert mode without any configuration constraints seems a good idea
  • APES Paf files are specific to the PRIMA instrument and can not be reused. Only Observing blocks (OB) should be considered for ASPRO. See OBX example file: CAL-lam_gru_PCN_MRK23.obx (this is a typical parameter file for preparing observations with AMBER/VLTI).
  • VMT is focused on a target model and has no observability feature
  • Dealing with aspro setting files is an important feature to keep the user session / history
  • Investigate plotting libraries that provide plot interactivity (batik supports svg format with javascript support ...)
  1. refresh plot with new data when the user changes anything in widgets
  2. interactive plot : the user can click on the plot to get information (predefined) or run other widgets

Topic attachments
I Attachment History Action Size Date Who Comment
Microsoft Word filedoc AsciiFileDescription.doc r1 manage 33.5 K 2010-03-29 - 15:05 LaurentBourges CHARA OB format description
Unknown file formatobx CAL-lam_gru_PCN_MRK23.obx r1 manage 1.5 K 2009-10-06 - 08:08 GillesDuvert this is a typical parameter file for pereparing observations with AMBER/VLTI
Unknown file formatobx SCI-HIP_2081_SB_PCN_MRK2300-NF.obx r1 manage 1.5 K 2010-03-29 - 15:04 LaurentBourges another AMBER/VLTI observing block
Texttxt StarList_V09_Orion.txt r1 manage 2.1 K 2010-03-29 - 15:05 LaurentBourges CHARA observing block
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Topic revision: r19 - 2010-06-07 - LaurentBourges
 
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