T Monocerotis
catalogues and names
| catalogues and names | T Mon, HR 2310, HD 44990, SAO 113845, BD +7 1273 |
data from The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version) (Hoffleit+, 1991)
position, motion, parallax:
| position (J2000) | RA: 6h 25min 13.1sec | DEC: +7° 5' 9'' | ||
| position (2000.72) | RA: 6h 25min 15sec | DEC: +7° 5' 7'' | ||
| position (B1900) | RA: 6h 19min 49sec | DEC: +7° 8' 25'' | ||
| proper motion (J2000) | RA: 0.017 arcsec/a | DEC: 0.004 arcsec/a | ||
| radial velocity | 32 km/s note: spectroscopic binaries |
|||
| rotational velocity | 21 km/s (uncertain) (variable) | |||
| trigonometric parallax | 0.005 arcsec | |||
| galactic coordinates | longitude: 203.63° | latitude: -2.55° | ||
magnitude
| visual magnitude | 5.98 (V on UBV Johnson system) |
spectral / color information
| spectral class | F7Iab-K1Iab |
| B-V-magnitude | 1.22 |
| U-B-magnitude | 1.04 |
| R-I-magnitude |
variability information
| variable star identification | T Mon |
| note (category: variability): | CDelta 5.58 - 6.62V, 27.0205d since 1933. Period has increased from 27.0093 before 1900, with mean value 27.024649d. |
double/multiple star system information
| note (category: double and multiple data): | IUE observations suggest an early-type companion, about A0. |
data from SKY2000 - Master Star Catalog (Myers+ 1997)
position, motion, parallax:
| position (J2000) | RA: 6h 25min 13.004sec | DEC: +7° 5' 8.19'' | ±0.2 arcsec | source: 52 |
| position (2000.72) | RA: 6h 25min 15sec | DEC: +7° 5' 6'' | JD: 2451806.24 | |
| proper motion (J2000) | RA: 0.0002 arcsec/a | DEC: -0.004 arcsec/a | source: 25 | |
| radial velocity | 32 km/s | source: 25 | ||
| trigonometric parallax | 0.005 arcsec | - | source: 25 | |
| galactic coord. (B1950) | longitude: 203.64° | latitude: -2.56° | ||
magnitude:
| visual | 5.6 (observed) | source: 31 |
| photographic | 7.6 | source: 16 |
spectral information:
| spectral class | G5 | source: 96 | |
| Morgan-Keenan | F7Iab-K1Iab | source: 25 | |
| B-magnitude | 7.2 ±0.05 | B-V-magnitude | 1.22 |
| U-magnitude | 8.24 ±0.05 | U-B-magnitude | 1.04 |
variability information:
| variability type | 111 |
| var. amplitude | 1.04 |
| var. period | 27.02 |
| var. epoch | 2443785 3. October 1978, 12:00:00 UT |
| next max light | 2451809.94 22. September 2000, 10:33:36 UT |
sources:
| 16 | PPM North and PPM South Catalogs and PPM Supplement |
| Roser, S., and U. Bastian, "Catalogue of Positions and Proper Motions," A&AS, Vol. 74, p. 449, 1988, and Bastian, U., et al., "Catalogue of Positions and Proper Motions - South," 1993 | |
| 25 | Bright Star Catalogue, 5th edition |
| Hoffleit, D. and Warren, W.H. Jr., The Bright Star Catalogue, 5th Revised Edition, Version 2, 1994 | |
| 30 | GCVS, 4th edition |
| Kholopov, P.N., et al., General Catalogue of Variable Stars, fourth edition, Moscow: Nauka Publishing House, 1985-88 | |
| 31 | CRM' (non-GCVS variable data) |
| Warren, W.H. Jr., Northern Hemisphere Catalog of Red Magnitudes, 1994 | |
| 52 | PPMN-HP subset |
| PPMN Star Catalogue (Reference 16) High-Precision Subset (Code H) | |
| 96 | SAO or HD/HDE Catalog |
| Reference from Value 1 or Reference from Value 2 | |
data from Smithsonian Astrophysical Observatory Star Catalog (SAO Staff 1966; USNO, ADC 1990)
position and proper motion:
| position (B1950) | RA: 6h 22min 31.027sec | DEC: +7° 6' 53.22'' | ±0.049 arcsec |
| position (2000.72) | RA: 6h 25min 15sec | DEC: +7° 5' 7'' | JD: 2451806.24 |
| position (J2000) | RA: 6h 25min 13.102sec | DEC: +7° 5' 9.25'' | |
| proper motion B1950 (FK4) | RA: 0.001 arcsec/a | DEC: 0.004 arcsec/a | ±0.012 arcsec/a in RA ±0.009 arcsec/a in DEC |
| proper motion J2000 (FK5) | RA: 0.0012 arcsec/a | DEC: 0.004 arcsec/a | |
| source of proper motion data | Determined by source catalog | ||
magnitude:
| visual | 5.8 (accuracy: 1 decimal) |
| source of visual magnitude data | Source cited in source catalog introduction. |
spectral information:
| spectral class | G5p |
| source of spectral data | Taken from the Henry Draper Catalogue or no spectrum in source catalog. |
remarks for duplicity and variability
| Variable star in visual magnitude in source catalog |
catalogues
| source catalogue | GC, catalogue number: 8291 |
| Durchmusterung | BD+07 1273 |
| Boss General Catalogue | 8291 |
| Henry Draper Catalogue | 44990 |
data from Combined General Catalogue of Variable Stars (Vol. I-III) (Kholopov+ 1998)
position:
| position (equinox 1950.0) | RA: 6h 22min 31sec | DEC: +7° 6' 53'' |
variability informations:
| variability type | DCEP | pulsating variable star |
| magnitute at max. brightness | 5.58 | |
| magnitute at min. brightness | 6.62 | |
| photometric system | visual, photovisual or Johnson's V | |
| epoch for maximum light [JD] | 2443784.615 3. October 1978, 02:45:36 UT |
|
| period [d] | 27.024649 | |
| next maximum light [JD] | 2451810.935753 23. September 2000, 10:27:29 UT |
|
| rising time | 27 % of period |
spectral information
| spectral class | F7Iab-K1Iab+A0V |
references
| to a study | Vol. I GCVS (see Kholopov et al. 1985-1988) |
| to a chart/photograph | Vol. I GCVS (see Kholopov et al. 1985-1988) |
miscanellous
| ID in the GCVS catalogue | 55/3 |
| constellation | Monoceros |
| notes on existence | The star is equivalent to '0550004 U'. |
| There are notes in published catalog. | |
variability type description
| variability type | description |
| DCEP | These are the classical cepheids, or Delta Cep-type variables. Comparatively young objects that have left the main sequence and evolved into the instability strip of the Hertzsprung-Russell (H-R) diagram, they obey the well-known Cepheid period-luminosity relation and belong to the young disk population. DCEP stars are present in open clusters. They display a certain relation between the shapes of their light curves and their periods. |