Information on Service 'The Sixth Fundamental Catalogue (FK6)'

[Use this service from your browser]

Further access options are discussed below

Parts I and III of the sixth fundamental catalog, a catalog of high-precision astrometry for bright stars combining centuries of ground-based observations as reflected in FK5 with HIPPARCOS astrometry. The result contains, in particular for the proper motions, statistically significant improvements of the Hipparcos data und represents a system of unprecedented accuracy for these 4150 fundamental stars. The typical mean error in pm is 0.35 mas/year for 878 basic stars, and 0.59 mas/year for the sample of the 3272 additional stars.

For a list of all services and tables belonging to this service's resource, see Information on resource 'The Sixth Fundamental Catalogue (FK6)'

Service Documentation

Input

The FK5 consists of observations coming from the past 200 years. Three parts were published giving the results of that work: First we have the Basic FK5 with 1535 stars, second the FK5 Extension with 3117 objects , and third the FK5 Supplement with 995 objects.

The results from the HIPPARCOS mission were published in 1997 (The Hipparcos and Tycho Catalogues).

The catalogue

The combination of the Hipparcos data and the FK5 was primarily done using only probable single stars. Two parts were published:

In FK6 part I (published 1999) 878 single stars (or objects that could be treated as single) were used from the Basic FK5, in FK6 part III (published 2000) 3272 single stars (or objects that could be treated as single) from the FK5 Extension and the FK5 Supplement were added.

The FK6 catalogue gives three solutions for each star: Besides the standard model for single stars, in which these were treated with a constant space velocitiy (single star mode, "SI"), two further solutions were added. The data of the standard single star mode "SI" are valid for real single stars only. For all other samples of stars it is, however, necessary to include the statistically significant influence of stars with companions in the solutions. The principles of this statistical astrometry were described by 1997A&A...325..367W and are also given in the printed FK6 catalogues.

The uncertain knowledge of the included correlations allows merely to produce two approximate solutions for short-period predictions of the position (short term prediction, "STP") or predictions for longer terms (long term predictions, "LTP"). The data of the STP mode should be used for epochs near to 1991.25, the mean observational epoch of Hipparcos, the data from the LTP mode for epochs differing from this mean epoch by more than 10-20 years.

Note that part II of the catalog (containing binary stars with orbits) was never published. See 2000A&A...360..399W for an orbit of Polaris.

Abbreviations used in the notes for the objects

af:
binarity is assumed optical since objects are approximately fixed
nc:
binarity is assumed optical since objects show no common proper motion
hv
binarity is assumed optical since objects have a high relative velocity
pc
binarity is assumed optical since objects have large spatial separation
no
no relative position given
oo
only one observation given in CCDM or WDS (hence no relative proper motion available)

Overview

You can access this service using:

This service is published as follows:

local means it is listed on our front page, ivo_managed means it has a record in the VO registry.

Input Fields

The following fields are available to provide input to the service (with some renderers, some of these fields may be unavailable):

NameTable Head DescriptionUnitUCD
DEC Delta (ICRS) Declination (ICRS decimal) deg pos.eq.dec
hscs_pos Position/Name Coordinates (as h m s, d m s or decimal degrees), or SIMBAD-resolvable object N/A N/A
hscs_sr Search radius Search radius in arcminutes N/A N/A
K_ae Excellent? Flag for astrometrically excellent stars, larger numbers are better (3 is best) N/A meta.code.qual
localid Identifier FK6 number of the star (it is identical with its FK5 or FK4sup number) N/A meta.id;meta.main
MAXREC Match limit Maximum number of records returned. Pass 0 to retrieve service parameters. N/A N/A
RA Alpha (ICRS) Right Ascension (ICRS decimal) deg pos.eq.ra
RESPONSEFORMAT Output Format File format requested for output. N/A meta.code.mime
SR Search Radius Search radius deg N/A
VERB Verbosity Exhaustiveness of column selection. VERB=1 only returns the most important columns, VERB=2 selects the columns deemed useful to the average user, VERB=3 returns a table with all available columns. N/A N/A

Default Output Fields

The following fields are contained in the output by default. More fields may be available for selection; these would be given below in the VOTable output fields.

NameTable Head DescriptionUnitUCD
comname Name Common Name N/A meta.id
dej2000 Dec The declination delta of the star at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6. deg pos.eq.dec;meta.main
e_dej2000 Err(Dec) Mean error of dej2000 at the central epoch epde deg stat.error;pos.eq.ra;meta.main
e_pmde Err(PM Dec) Mean error of pmde in the SI mode. deg/yr stat.error;ps.pm;pos.eq.dec;meta.main
e_pmdeHIP Err. PM Dec (HIP) Mean error in PM(Dec) in HIP mode deg/yr stat.error;pos.pm;pos.eq.dec
e_pmdeLTP Err. PM Dec (LTP) Mean error in PM(Dec) in LTP mode deg/yr stat.error;pos.pm;pos.eq.dec
e_pmdeSTP Err. PM Dec (STP) Mean error in PM(Dec) in STP mode deg/yr stat.error;pos.pm;pos.eq.dec
e_pmra Err(PM RA) Mean error of pmra in the SI mode. deg/yr stat.error;ps.pm;pos.eq.ra;meta.main
e_pmraHIP Err. PM RA (HIP) Mean error in PM(RA)*cos(delta) in HIP mode deg/yr stat.error;pos.pm;pos.eq.ra
e_pmraLTP Err. PM RA (LTP) Mean error in PM(RA)*cos(delta) in LTP mode deg/yr stat.error;pos.pm;pos.eq.ra
e_pmraSTP Err. PM RA (STP) Mean error in PM(RA)*cos(delta) in STP mode deg/yr stat.error;pos.pm;pos.eq.ra
e_pres Err.(Par.) Mean error of parallax deg stat.error;pos.parallax
e_raj2000 Err(RA) Mean error of raj2000 in the SI mode, cos(delta) applied. deg stat.error;pos.eq.ra;meta.main
epde Ep(Dec) Central epoch of delta in the SI mode. yr time.epoch;pos.eq.dec
epra Ep(RA) Central epoch of raj2000 in the SI mode. yr time.epoch;pos.eq.ra
hipno HIP# Number of the star in the HIPPARCOS Catalogue (ESA 1997) N/A meta.id
K_ae Excellent? Flag for astrometrically excellent stars, larger numbers are better (3 is best) N/A meta.code.qual
K_bin Binarity Flag for the double-star nature of the object (see note) Note M N/A meta.code.multip
K_Delta_mu Dmu Flag for the double-star nature of the object based on differences between various proper motions (see note) Note D N/A meta.code.multip
localid Identifier FK6 number of the star (it is identical with its FK5 or FK4sup number) N/A meta.id;meta.main
note Note Note for this object N/A meta.note
pmde PM δ The proper-motion component mu_delta of the star in delta at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6. deg/yr pos.pm;pos.eq.dec;meta.main
pmdeHIP PM Dec (HIP) Proper motion in Dec in HIP mode deg/yr pos.pm;pos.eq.dec
pmdeLTP PM Dec (LTP) Proper motion in Dec in LTP mode deg/yr pos.pm;pos.eq.dec
pmdeSTP PM Dec (STP) Proper motion in Dec in STP mode deg/yr pos.pm;pos.eq.dec
pmra PM α The proper-motion component of the star in alpha at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6, cos(delta) applied. deg/yr pos.pm;pos.eq.ra;meta.main
pmraHIP PM RA (HIP) Proper motion in RA, cos(delta) applied, in HIP mode deg/yr pos.pm;pos.eq.ra
pmraLTP PM RA (LTP) Proper motion in RA, cos(delta) applied, in LTP mode deg/yr pos.pm;pos.eq.ra
pmraSTP PM RA (STP) Proper motion in RA, cos(delta) applied, in STP mode deg/yr pos.pm;pos.eq.ra
pres Parallax 'Resulting' parallax p_res of the star. This is either the HIPPARCOS parallax or a photometric/spectroscopic parallax. deg pos.parallax
raj2000 RA The right ascension alpha of the star at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6. deg pos.eq.ra;meta.main
sect FK6 part FK6 part of this record N/A meta.id.part;meta.main
src_par Src(Par.) Source of parallax (H=HIPPARCOS, P=Newly determined photometric or spectroscopic parallax) N/A meta.code;pos.parallax
v_rad v_rad Radial velocity km/s spect.dopplerVeloc;pos.heliocentric
varFlag Var? Flag for the variability of the brightness of the star, taken from the HIPPARCOS Catalogue (see note) Note V N/A meta.code;src.var
vmag m_V Apparent visual magnitude m_V of the star, taken from the HIPPARCOS Catalogue mag phot.mag;em.opt.V

VOTable Output Fields

The following fields are available in VOTable output. The verbosity level is a number intended to represent the relative importance of the field on a scale of 1 to 30. The services take a VERB argument. A field is included in the output if their verbosity level is less or equal VERB*10.

NameTable Head DescriptionUnitUCD Verb. Level
localid Identifier FK6 number of the star (it is identical with its FK5 or FK4sup number) N/A meta.id;meta.main 1
raj2000 RA The right ascension alpha of the star at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6. deg pos.eq.ra;meta.main 1
dej2000 Dec The declination delta of the star at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6. deg pos.eq.dec;meta.main 1
sect FK6 part FK6 part of this record N/A meta.id.part;meta.main 3
pmra PM α The proper-motion component of the star in alpha at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6, cos(delta) applied. deg/yr pos.pm;pos.eq.ra;meta.main 5
pmde PM δ The proper-motion component mu_delta of the star in delta at epoch and equinox J2000.0 in the ICRS/HIPPARCOS system for the SI mode of the FK6. deg/yr pos.pm;pos.eq.dec;meta.main 5
K_ae Excellent? Flag for astrometrically excellent stars, larger numbers are better (3 is best) N/A meta.code.qual 5
e_raj2000 Err(RA) Mean error of raj2000 in the SI mode, cos(delta) applied. deg stat.error;pos.eq.ra;meta.main 15
e_pmra Err(PM RA) Mean error of pmra in the SI mode. deg/yr stat.error;ps.pm;pos.eq.ra;meta.main 15
e_dej2000 Err(Dec) Mean error of dej2000 at the central epoch epde deg stat.error;pos.eq.ra;meta.main 15
e_pmde Err(PM Dec) Mean error of pmde in the SI mode. deg/yr stat.error;ps.pm;pos.eq.dec;meta.main 15
pres Parallax 'Resulting' parallax p_res of the star. This is either the HIPPARCOS parallax or a photometric/spectroscopic parallax. deg pos.parallax 15
v_rad v_rad Radial velocity km/s spect.dopplerVeloc;pos.heliocentric 15
vmag m_V Apparent visual magnitude m_V of the star, taken from the HIPPARCOS Catalogue mag phot.mag;em.opt.V 15
pmraSTP PM RA (STP) Proper motion in RA, cos(delta) applied, in STP mode deg/yr pos.pm;pos.eq.ra 17
pmdeSTP PM Dec (STP) Proper motion in Dec in STP mode deg/yr pos.pm;pos.eq.dec 17
pmraLTP PM RA (LTP) Proper motion in RA, cos(delta) applied, in LTP mode deg/yr pos.pm;pos.eq.ra 17
pmdeLTP PM Dec (LTP) Proper motion in Dec in LTP mode deg/yr pos.pm;pos.eq.dec 17
pmraHIP PM RA (HIP) Proper motion in RA, cos(delta) applied, in HIP mode deg/yr pos.pm;pos.eq.ra 17
pmdeHIP PM Dec (HIP) Proper motion in Dec in HIP mode deg/yr pos.pm;pos.eq.dec 17
note Note Note for this object N/A meta.note 18
varFlag Var? Flag for the variability of the brightness of the star, taken from the HIPPARCOS Catalogue (see note) Note V N/A meta.code;src.var 19
epra Ep(RA) Central epoch of raj2000 in the SI mode. yr time.epoch;pos.eq.ra 21
epde Ep(Dec) Central epoch of delta in the SI mode. yr time.epoch;pos.eq.dec 21
e_pmraSTP Err. PM RA (STP) Mean error in PM(RA)*cos(delta) in STP mode deg/yr stat.error;pos.pm;pos.eq.ra 21
e_pmdeSTP Err. PM Dec (STP) Mean error in PM(Dec) in STP mode deg/yr stat.error;pos.pm;pos.eq.dec 21
e_pmraLTP Err. PM RA (LTP) Mean error in PM(RA)*cos(delta) in LTP mode deg/yr stat.error;pos.pm;pos.eq.ra 21
e_pmdeLTP Err. PM Dec (LTP) Mean error in PM(Dec) in LTP mode deg/yr stat.error;pos.pm;pos.eq.dec 21
e_pmraHIP Err. PM RA (HIP) Mean error in PM(RA)*cos(delta) in HIP mode deg/yr stat.error;pos.pm;pos.eq.ra 21
e_pmdeHIP Err. PM Dec (HIP) Mean error in PM(Dec) in HIP mode deg/yr stat.error;pos.pm;pos.eq.dec 21
K_bin Binarity Flag for the double-star nature of the object (see note) Note M N/A meta.code.multip 23
K_Delta_mu Dmu Flag for the double-star nature of the object based on differences between various proper motions (see note) Note D N/A meta.code.multip 23
hipno HIP# Number of the star in the HIPPARCOS Catalogue (ESA 1997) N/A meta.id 25
comname Name Common Name N/A meta.id 25
e_pres Err.(Par.) Mean error of parallax deg stat.error;pos.parallax 25
src_par Src(Par.) Source of parallax (H=HIPPARCOS, P=Newly determined photometric or spectroscopic parallax) N/A meta.code;pos.parallax 25

VOResource XML (that's something exclusively for VO nerds)

Note D

K_Delta_mu is a flag for the double-star nature of the object based on differences between (see 1999A&A...346..675W).

1:
single-star candidate
2:
Delta_mu binary
blank:
uncertain (between 1 and 2), or the binary nature which is indicated by other data does not allow to classify the object as a single-star candidate
Note M

K_bin is a flag for the double-star nature of the object: K_bin = 10d1+d2

First digit d1

The first digit d1 describes the information on the double-star nature based on the proper-motion differences Delta_mu. The method and the meaning of the corresponding test parameters F are explained in 1999A&A...346..675W.

1:
all values of F (F_FH, F_0H, F_0(GC)H, F_0F) are below 2.49
2:
at least one value of F (F_FH, F_0H, F_0(GC)H, F_0F) is larger than 3.44
3:
all other (intermediate) cases

Second digit d2:

The second digit d2 describes the information on the double-star nature based on various other methods. If the data indicate various kinds of binarity, the 'astrometrically most disturbing' effect is given.

1:
single star indicated
2:
the star is a member of a visual binary (gravitationally bound system), or the object is resolved by speckle interferometry
3:
the object is suspected to be a visual binary (mainly due to HIPPARCOS)
4:
the star has at least one optical companion with a separation of rho<60 arcsec
5:
the star has at least one optical companion, but all companions have a separation of rho >= 60"
6:
astrometric binary (mainly the non-standard solutions O, G, V, X of HIP)
7:
spectroscopic binary with a known orbit, or the star is an eclipsing binary
8
the radial velocity of the star is variable (indicating a spectroscopic binary), or the object shows a composite spectrum (indicating a double star)
9:
the radial velocity of the star may be variable (possible indication for a spectroscopic binary), or the object may show a composite spectrum (possibly indicating a double star), or other weak indications of binarity, or the star has a (suspected) planetary companion
Note V

A nonempty varFlag field indicates that the star is variable with an amplitude of

1:
< 0.06 mag
2:
0.06 .. 0.6 mag
3:
> 0.6mag