To be compatible with what we already have done with OMEGA and PFS data: leave the Nbins everywhere - For NOMAD, it will be always =1
if Nbins = 1: no need to use 2D (3D) matrices; for example AOTFFrequency will be a 1-column matrix (vector) of length Nspectra

All dimensions are of the following: [Number of spectra] x [Number of bins] x [Number of pixels]

(1 subdomain, 1 detector bin) = 1 spectrum
!! For SO and LNO: Nbins = 1; and
Nspectra = [Nb_observationsx Nb_Detector Bins]

for UVIS : Nbins = 1;
Nspectra = Nb_observations

Group

Dataset

Observation mode

Description

Units

Types

Shape

SO/LNO Example

UVIS Example

Geometry

ObsAlt

Nadir & Occ

Altitude of observer above target ellipsoid

KILOMETRES

float

[Nspectra x Nbins] x [2]

Geometry

TiltAngle

Nadir

Slit roll angle

DEGREES

float

[Nspectra x Nbins] x [2]

e.g. slit roll angle between long edge of slit and surface normal (occultation) or s/c direction (nadir)

-999

Geometry

SubObsLat

Nadir & Occ

Sub-Satellite Latitude

DEGREES

float

[Nspectra x Nbins] x [2]

-90°<angle<90°

Geometry

SubObsLon

Nadir & Occ

Sub-Satellite Longitude

DEGREES

float

[Nspectra x Nbins] x [2]

-180°<angle<180°

Geometry

LSubS

Nadir & Occ

Planetocentric longitude Ls

DEGREES

float

[Nspectra x Nbins] x [2]

0°<angle<360°

Geometry

SubSolLon

Nadir & Occ

Sub-Solar Longitude

DEGREES

float

[Nspectra x Nbins] x [2]

-180°<angle<180°

Geometry

SubSolLat

Nadir & Occ

Sub-Solar Latitude

DEGREES

float

[Nspectra x Nbins] x [2]

-90°<angle<90°

Geometry

DistToSun

Nadir & Occ

Distance from Planet to Sun

Astron Unit

float

[Nspectra x Nbins] x [2]

Geometry

SpdObsSun

Nadir & Occ

Speed of observer (TGO) wrt Sun

KILOMETRES/S

float

[Nspectra x Nbins] x [2]

Geometry

SpdTargetSun

Nadir & Occ

Speed of target (Mars) wrt Sun

KILOMETRES/S

float

[Nspectra x Nbins] x [2]

Geometry

ObservationDate

Nadir & Occ

UTC start/end time of observation

NO UNITS

String

[Nspectra x Nbins] x [2]

1900-01-01

Geometry

ObservationTime

Nadir & Occ

UTC start/end time of observation

NO UNITS

String

[Nspectra x Nbins] x [2]

00-00-00.000

Geometry

ObservationDateTime

Nadir & Occ

UTC start/end time of valid observation points taken directly from SPICE

NO UNITS

String

[Nspectra x Nbins] x [2]

1900 JAN 01 00:00:00.000

The FOV will be defined using multiple points, each of which is a hdf5 group, where N=0,1,2,3 etc. Within each group there are multiple datasets given below

N=0 defines the centre point. For SO/LNO nadir observations, N=1-4 define the corners of the FOV

Geometry/PointN

PointXY

Nadir & Occ

Relative position of point w.r.t. bin or slit

NO UNITS

float

[2] (per point)

e.g. [-1,-1] for the lower left corner

e.g. [0,-1] for the bottom of the circular FOV

Geometry/PointN

Lat

Nadir & Occ

Tangent point latitude for this point (occ) or surface latitude (nadir)

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

-90°<angle<90°

Geometry/PointN

Lon

Nadir & Occ

Tangent point longitude for this point (occ) or surface latitude (nadir)

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

-180°<angle<180°

Geometry/PointN

LST

Nadir & Occ

Local solar time

HOURS

float

[Nspectra x Nbins] x [2] (per point)

0<hours<23.9999999

Geometry/PointN

LOSAngle

Nadir & Occ

LOS angle (180 - emission angle for nadir), angle between planet centre and point (occ) for this point

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

0°<angle<180°

Geometry/PointN

TangentAlt

Occ

Tangent point altitude above Mars ellipsoid for each point

KILOMETRES

float

[Nspectra x Nbins] x [2] (per point)

Geometry/PointN

SunSZA

Nadir

Solar zenith angle for this point

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

0°<angle<180°

Geometry/PointN

SunAzi

Nadir

Sun azimuthal angle for this point

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

0°<angle<180°

Geometry/PointN

IncidenceAngle

Nadir

Incidence angle for this point

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

0°<angle<180°

Geometry/PointN

EmissionAngle

Nadir

Emission angle for this point

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

0°<angle<180°

Geometry/PointN

PhaseAngle

Nadir

Phase angle for this point

DEGREES

float

[Nspectra x Nbins] x [2] (per point)

0°<angle<180°

Geometry/PointN

FOVWeight

all

Weigth of the Point

NO UNITS

float

[Nspectra x Nbins] x [1] (per point)

<=1.0 (1.0 for the Point0, central LOS)

<=1.0