← Observing starter catalogues
Catalogue record
HR 4731
Alp2Cru
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A bounded starter sample: 50 bright-star records from HEASARC BSC5P, including 23 records with identified double-star components and historical separations, plus 108 OpenNGC deep-sky records associated with Messier numbers.
These are static catalogue measurements, not current sky positions or a complete census. Double-star records may describe the same pair; a pair is not necessarily a gravitationally bound binary. Separation dates and companion position angles are not available.
Missing measurements are unknown, not zero. Sizes can come from different wavelength bands and do not guarantee an object’s visible extent. No observability or equipment-resolution prediction is made here.
- Stable source identifier
- bsc5p:hr4731
- Source object type
- star
- Catalogue right ascension
- 186.6521 degrees
- Catalogue declination
- -63.0994 degrees
- Recorded magnitude
- 1.73 · V (BSC5P; retain code/uncertainty flags)
Uncertainty flag: None reported; source code: None reported - Catalogue major / minor axes
- Not reported / Not reported
- Components
- AB
- Historical component separation
- 4.4 arcsec
- Separation measurement epoch
- Not reported
- Companion position angle
- Not reported
Coordinate interpretation
- Verified coordinate frame
- FK5
- Frame equinox
- J2000.0
- Catalogue reference epoch
- Julian year 2000.0
- Individual observation epoch
- Not reported
- RA proper motion, including cosine of declination
- -0.034 arcsec/year
- Declination proper motion
- -7 × 10⁻³ arcsec/year
The reference epoch describes when the catalogue position is expressed. It does not establish when individual observations were taken. Equinox describes the orientation of the coordinate axes.
Angular proper motion is available for a bounded calculation, but has not been applied here. No distance, radial velocity, perspective acceleration or companion orbit is inferred.
This page shows unchanged catalogue coordinates. It does not calculate current sky positions or observability.
Source and reuse: bsc5p
Hoffleit and Warren (1991), Bright Star Catalog, 5th revised preliminary edition; NASA/GSFC HEASARC
Original source / pinned release · NASA government-works; HEASARC free-use policy
Credit Hoffleit and Warren and NASA/GSFC HEASARC when reusing these records. Retain the source flags and historical measurement limitations.
- Selection
- Vmag <= 2.0, excluding 14 documented nonstellar HR identifiers
- Retrieved
- 2026-10-01T21:40:09.869946+00:00
- Reviewed subset SHA256
- 7fe926d80b535f9422ca81f8f3fee1d6422de29adaecfbd2f14b1a93fe5134b9
Original file hashes
- bsc5p.tdat
- e2b2f8e9d615426f9478f88061235976143d49d8b25c6c15df3f3661c7095b53
Coordinate-frame evidence
Exact source identifiers matched: 50. Evidence retrieved: 2026-10-01.
- Pinned response SHA256
- a3f83273ccaecf913a0d8e077413062c20ce1fc01ce890c80615a9572d5f1be9
Original source fields and flags
Original strings preserve missing values, photometric flags and per-field source codes. Blank means no value was supplied. No proper motion or companion position is calculated here.
- ads
- Not supplied
- ads_comp
- B
- alt_name
- Alp2Cru
- bii
- -0.3629
- bv_color
- -0.26
- bv_uncert
- Not supplied
- cdec
- -630558
- cdec_1950
- -624922
- class
- 2215
- cra
- 122636.5
- cra_1950
- 122348.4
- dec
- -63.0994
- dec_1900
- -62.53333333453
- dec_1950
- -62.8227
- dm_cat
- CP
- dm_num
- -62 2745
- fk5
- Not supplied
- glat
- -0.36
- glon
- 300.13
- hd
- 108249
- hr
- 4731
- ir_flag
- Not supplied
- lii
- 300.128
- m_cnt
- 3
- m_id
- AB
- m_mdiff
- 0.4
- m_sep
- 4.4
- multiple
- W
- name
- HR 4731
- note
- *
- par_code
- D
- parallax
- 0.008
- pmdec
- -0.007
- pmra
- -0.034
- ra
- 186.6521
- ra_1900
- 185.2604166667
- ra_1950
- 185.9518
- radvel
- -1
- radvel_comm
- Not supplied
- ri_code
- Not supplied
- ri_color
- Not supplied
- rotvel
- 197
- rotvel_comm
- Not supplied
- rotvel_uncert
- Not supplied
- sao
- Not supplied
- spect_code
- Not supplied
- spect_type
- B1V
- ub_color
- -0.95
- ub_uncert
- Not supplied
- var_id
- Not supplied
- vmag
- 1.73
- vmag_code
- Not supplied
- vmag_uncert
- Not supplied