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 ...)
- refresh plot with new data when the user changes anything in widgets
- interactive plot : the user can click on the plot to get information (predefined) or run other widgets
Dev Task list
This section gathers TODO or discussed development tasks or enhancements and their status (pending, done or postponed) according to version 0.3b8 (18 may 2010) :
Source definition :
- define manually a target : custom widget to enter coordinates and required magnitudes for a given instrument : done (added an optional star name - no magnitude yet)
- SimBad widget : simbad can return several query results if the search criteria is not sufficiently restrictive : in such case, the results should be displayed to the user to let him choose among targets.
Baseline definition :
- VLTI : allow an advanced user to enter manually the list of stations (E0 A0 H0) instead of choosing a valid configuration for the corresponding period
- CHARA : how to associate a beam to a station (V1 = E1, V2=S2 ...) ? this contributes to the OPD and it is used in CHARA OB.
Observability plot
- trou du zenith ?
- transit indication : the plot should include a mark (or the time) at the exact time of transit (zenital angle = 0, elevation has its maximum value ) : done (added a diamond mark)
- elevation marks : like aspro1, indicate the elevation of the target with ticks (20,40,60 ...) : done
- moon information : illumination fraction, moon rise/set, check the distance of a target with the moon is higher than 10°
- interactive UI : the user should have details in a pop up or a contextual window with azimuth / elevation, airmass, atmospheric refraction, distance from sun, moon : postponed (technical issues)
UV coverage plot
- display the legend of the model image i.e. the palette scale
- alternate units to MLambda like meter or arcsec-1. In such case do not display the UV segments representing the the wave length bandpath
- indicate the UT time corresponding to UV points (Alain) in a pop up (UT / LST / HA)
- custom uv coverage : user defined points = list of (date / UT time) in order to reproduce an observation made at different date/time
Model Editor
- add missing models (Gaussian, ring, Limb-Darkened Disk) - see JmmcAsproTargetModel : done
- add a button to normalize the total of flux_weight to 1 : done
Export to OI Fits File (high priority)
export to OI Fits file the visibilities for a given target model : pending
Export to Observing blocks (high priority)
- VLTI OB : done for AMBER and MIDI instruments
- CHARA OB : pending
This component
will be a generic OIFits file viewer to plot visibilities that must be interoperable with aspro 2, LITpro ...
A new JMMC module named OITools is in development :
- It only supports loading entirely an OIFits file into an object memory model and validation (OIVal like)
- Saving an OIFits file is coming soon
It uses the nom.tam fits library from HEASARC instead of eso JFits library.
Other items
- interferometer map with station positions and selected base lines : done
- user preferences with color palette editor, default target model : started