Dastcom5 parameters

avail:

  • a if it is available for asteroids.

  • c if it is available for comets.

  • [number]+ since which version of DASTCOM5 is available.

avail

Label

Definition

ac/3+

EPOCH

Time of osc. orbital elements solution, JD (CT,TDB)

ac/3+

CALEPO

Time of osc. orbital elements solution, YYYYDDMM.ffff

ac/3+

MA

Mean anomaly at EPOCH, deg (elliptical & hyperbolic cases “9.999999E99” if not available)

ac/3+

W

Argument of periapsis at EPOCH, J2000 ecliptic, deg.

ac/3+

OM

Longitude of ascending node at EPOCH, J2000 ecliptic,deg.

ac/3+

IN

Inclination angle at EPOCH wrt J2000 ecliptic, deg.

ac/3+

EC

Eccentricity at EPOCH

ac/3+

A

Semi-major axis at EPOCH, au

ac/3+

QR

Perihelion distance at EPOCH, au

ac/3+

TP

Perihelion date for QR at EPOCH, JD (CT,TDB)

ac/3+

TPCAL

Perihelion date for QR at EPOCH, format YYYYMMDD.fff

ac/5+

TPFRAC

Decimal (fractional) part of TP for extended precision

ac/4+

SOLDAT

Date orbit solution was performed, JD (CT,TDB)

ac/4+

SRC(01)

Square root covariance vector. Vector-stored upper- triangular matrix with order {EC,QR,TP,OM,W,IN,{ ESTL }}

ac/3+

H

Absolute visual magnitude (IAU H-G system) (99=unknown)

ac/3+

G

Mag. slope parm. (IAU H-G)(99=unknown & 0.15 not assumed)

c/3+

M1

Total absolute magnitude, mag.

c/3+

M2

Nuclear absolute magnitue, mag.

c/4+

K1

Total absolute magnitude scaling factor

c/4+

K2

Nuclear absolute magnitude scaling factor

c/4+

PHCOF

Phase coefficient for K2= 5

ac/3+

A1

Non-grav. accel., radial component, [s:10^-8 au/day^2]

ac/3+

A2

Non-grav. accel., transverse component,[s:10^-8 au/day^2

ac/4+

A3

Non-grav. accel., normal component, [s:10^-8 au/day^2]

c/4+

DT

Non-grav. lag/delay parameter, days

ac/5+

R0

Non-grav. model constant, normalizing distance, au

ac/5+

ALN

Non-grav. model constant, normalizing factor

ac/5+

NM

Non-grav. model constant, exponent m

ac/5+

NN

Non-grav. model constant, exponent n

ac/5+

NK

Non-grav. model constant, exponent k

c/4+

S0

Center-of-light estimated offset at 1 au, km

c/5+

TCL

Center-of-light start-time offset, d since “ref.time”

a /5+

LGK

Surface thermal conductivity log_10(k), (W/m/K)

ac/5+

RHO

Bulk density, kg/m^3

ac/5+

AMRAT

Solar pressure model, area/mass ratio, m^2/kg

c/5+

AJ1

Jet 1 acceleration, au/d^2

c/5+

AJ2

Jet 2 acceleration, au/d^2

c/5+

ET1

Thrust angle, colatitude of jet 1, deg.

c/5+

ET2

Thrust angle, colatitude of jet 2, deg.

c/5+

DTH

Jet model diurnal lag angle, deg. (delta_theta)

ac/5+

ALF

Spin pole orientation, RA, deg.

ac/5+

DEL

Spin pole orientation, DEC, deg.

ac/5+

SPHLM3

Earth gravity sph. harm. model limit, Earth radii

ac/5+

SPHLM5

Jupiter grav. sph. harm. model limit, Jupiter radii

ac/3+

RP

Object rotational period, hrs

ac/3+

GM

Object mass parameter, km^3/s^2

ac/3+

RAD

Object mean radius, km

ac/5+

EXTNT1

Triaxial ellipsoid, axis 1/largest equat. extent, km

ac/5+

EXTNT2

Triaxial ellipsoid, axis 2/smallest equat. extent, km

ac/5+

EXTNT3

Triaxial ellipsoid, axis 3/polar extent, km

ac/4+

MOID

Earth MOID at EPOCH time, au; ‘99’ if not computed

ac/3+

ALBEDO

Geometric visual albedo, 99 if unknown

a /3+

BVCI

B-V color index, mag., 99 if unknown

a /5+

UBCI

U-B color index, mag., 99 if unknown

a /5+

IRCI

I-R color index, mag., 99 if unknown

ac/4+

RMSW

RMS of weighted optical residuals, arcsec

ac/5+

RMSU

RMS of unweighted optical residuals, arcsec

ac/5+

RMSN

RMS of normalized optical residuals

ac/5+

RMSNT

RMS of all normalized residuals

a /5+

RMSH

RMS of abs. visual magnitude (H) residuals, mag.

c/5+

RMSMT

RMS of MT estimate residuals, mag.

c/5+

RMSMN

RMS of MN estimate residuals, mag.

ac/3+

NO

Logical record-number of this object in DASTCOM

ac/4+

NOBS

Number of observations of all types used in orbit soln.

ac/4+

OBSFRST

Start-date of observations used in fit, YYYYMMDD

ac/4+

OBSLAST

Stop-date of observations used in fit, YYYYMMDD

ac/5+

PRELTV

Planet relativity “bit-switch” byte: bits 0-7 are set to 1 if relativity for corresponding planet was computed, 0 if not. For example, if Earth & Jupiter, FORTRAN(95) statement IBITS(PRELTV,J,1) should return 1 when J=2 or J=4, but zero for every other J through 7. No provision for supporting Pluto relativity.

ac/5+

SPHMX3

Earth grav. model max. degree; 0=point-mass, 2= J2 only, 3= up to J3 zonal, 22= 2x2 field, 33=3x3 field, etc.

ac/5+

SPHMX5

Jupiter grav. max. deg.; 0=point-mass, 2= J2 only, 3= up to J3 zonal, 22= 2x2 field, 33=3x3 field, etc.

ac/5+

JGSEP

Galilean satellites used as sep. perturbers; 0=no 1=yes

ac/5+

TWOBOD

Two-body orbit model flag; 0=no 1=yes

ac/5+

NSATS

Number of satellites; 99 if unknown.

ac/4+

UPARM

Orbit condition code; 99 if not computed

ac/4+

LSRC

Length of square-root cov. vector SRC (# elements used)

c/3+

IPYR

Perihelion year (i.e., 1976, 2012, 2018, etc.)

ac/3+

NDEL

Number of radar delay measurements used in orbit soln.

ac/3+

NDOP

Number of radar Doppler measurements used in orbit soln.

c/5+

NOBSMT

Number of magnitude measurements used in total mag. soln.

c/5+

NOBSMN

Number of magnitude measurements used in nuc. mag. soln.

c/3+

COMNUM

IAU comet number (parsed from DESIG)

ac/3+

EQUNOX

Equinox of orbital elements (‘1950’ or ‘2000’)

ac/4+

PENAM

Planetary ephemeris ID/name

ac/3+

SBNAM

Small-body perturber ephemeris ID/name

a /3

SPTYPT

Tholen spectral type

a /4+

SPTYPS

SMASS-II spectral type

ac/3+

DARC

Data arc span (year-year, OR integer # of days)

a /3+

COMNT1

Asteroid comment line #1

a /3+

COMNT2

Asteroid comment line #2

c/3+

COMNT3

Comet comment line #1

c/3+

COMNT4

Comet comment line #2

ac/3+

DESIG

Object designation

ac/4+

ESTL

Dynamic parameter estimation list. Last symbol set to ‘+’ if list is too long for field; check object record comments field for full list.

ac/3+

IREF

Solution reference/ID/name

ac/3+

NAME

Object name