MIZAR ===== Visual magnitude: 2.23 Spectral type: A2V Distance: 78.2 +/- 1.1 light years Luminosity: 59.7 +/- 1.7 x Sun's luminosity Position information for 29 ene 2003 11:53:41 (Julian day number 2452668.95395) Apparent RA (epoch of date): 13h 24m 03.22s Apparent Dec (epoch of date): +54° 54' 18.7" Constellation: Ursa Major Altitude: +31° 20' 52" Azimuth: 317° 45' 56" Transit: 5h 43m 16s The star is circumpolar and never rises or sets Names and Catalog Numbers Proper name: Mizar Bayer letter: z Ursae Majoris Flamsteed number: 79 Ursae Majoris Tycho catalog number: TYC 3850-1385-1 Hipparcos number: HIP 65378 Henry Draper number: HD 116656 DM number: BD +55 1598 PPM number: PPM 34007 SAO number: SAO 28737 Bright star number: HR 5054 Star Atlas Chart Numbers Herald-Bobroff Astroatlas, Chart C-11 Millennium Star Atlas, Charts 571-572 (Vol II) Sky Atlas 2000.0, Chart 2 Uranometria 2000 Chart 48, Vol 1 Yale Bright Star Catalog Data Preliminary Version of the Bright Star Catalogue, 5th Revised Edition. Dorrit Hoffleit, Department of Astronomy, Yale University, Wayne H. Warren Jr., ST Systems Corporation, National Space Science Data Center, NASA Goddard Space Flight Center (1991) Bright star catalog number: HR 5054 Position: RA (J2000.0): 13h 23m 55.5s Dec (J2000.0): +54° 55' 31" RA (B1900.0): 13h 19m 54.0s Dec (B1900.0): +55° 26' 51" Galactic coordinates (system II): Longitude: 113.11° Latitude: 61.58° Magnitude and spectral information: Magnitude: 2.27 [V on UBV (Johnson) system] B-V on Johnson system: +0.02 U-B on Johnson system: +0.03 R-I: -0.02 (on Johnson system) Spectral type: A1VpSrSi Annual proper motion for J2000.0 on FK5 system: RA: +0.122" Dec: -0.020" Trigonometric parallax: +.047" Heliocentric radial velocity: -006 km/sec Radial velocity comments: Spectroscopic binary; double-lined spectra; orbital data available Projected rotational velocity (v sin i): 32 km/sec Double/Multiple star information: ADS catalog number (Aitken 1934): ADS 8891 Letter identifications: A Component data: Identification: AP Magnitude difference: 1.7 Separation: 0.0" Total number known: 4 Variable star designation: 6224 Cross references to other catalogs: Durchmusterung: BD+55 1598 Henry Draper catalog: HD 116656 SAO catalog: SAO 28737 FK5 catalog: 497 Infrared source: NASA Merged Infrared Catalogue, Schmitz et al. 1978. Remarks Double/multiple stars: Aa = AP 3.0 A2V, 3.0 A2V, sep. 0.0115", 0.056y, a = 0.012". Combined mag., colors AP. Binary with HR 5055. Alcor, HR 5062, at 709", CPM. Dynamical parallax: 0.046". Group membership: "Dipper Stars;" Sirius group; UMa moving cluster. Names: MIZAR; Mizat; Mirza. Spectra: Combined spectrum for Aa also classified A1VpSrSi. Spectroscopic binary: ADS 8891Aa, 20.5386d, K 68.8k/s, V0 -5.6k/s, msin3i 1.60, asini 16.4. i 60d. vsini both components 32k/s. The first SB to have been discovered, by Pickering in 1889. First resolved by 20-foot interferometer at Mt. Wilson by Pease in 1925, sep. 0.01". Hipparcos Catalog Data Hipparcos Catalogue (ESA SP-1200, 1997). Hipparcos Identifier/Proximity Flag Catalog number: HIP 65378 Proximity flag: None Descriptor V magnitude: 2.23 Source of V magnitude: Median Hipparcos magnitude (Hp), combined with information on the colour index (either V-I or Bt-Vt), in combination with the luminosity class. Main Mission Astrometric Data Equatorial coordinates (epoch J2000.0, ICRS) RA: 13h 23m 55.5429s Dec: +54° 55' 31.303" The specified RA/dec coordinates refer to component 'A' of a double or multiple system. Standard errors of the equatorial coordinates (epoch J1991.25) RA: 0.00049 arcsec Dec: 0.00051 arcsec Trigonometric parallax: 0.04173 arcsec Standard error of the parallax: 0.00061 arcsec Proper motion components (epoch J1991.25, ICRS) RA: +0.21097 arcsec/yr Dec: -0.02201 arcsec/yr Standard errors of the proper motion components RA: 0.00084 arcsec Dec: 0.00048 arcsec Radial velocity: -5.6 km/sec Percentage of data that had to be rejected to obtain an acceptable astrometric solution (F1): 13% Goodness-of-fit parameter (F2): 0.95 Tycho Photometry and Colour Indices Mean magnitude in the Tycho photometric system, Bt: 2.290 Standard error of the Bt magnitude: 0.002 Mean magnitude in the Tycho photometric system, Vt: 2.227 Standard error of the Vt magnitude: 0.003 Bt and Vt data refer to component 'A' of the star system. Johnson B-V colour index: 0.057 Standard error: 0.004 Source of B-V value: Determined from the transformed Tycho Bt-Vt data. Cousins' V-I colour index: 0.07 Standard error: 0.00 Source of V-I value: Method L Main Mission Photometry Median magnitude in the Hipparcos photometric system, Hp: 2.2540 Standard error in median magnitude: 0.0088 mag Scatter of Hp observations: 0.041 mag Number of Hp observations: 108 Photometry refers to component 'A' of a double or multiple system. Main Mission Variability Observed magnitude at maximum and minimum luminosities: Mag at max, Hp: 2.22 (5th percentile) Mag at min, Hp: 2.36 (95th percentile) Type of variability: a "duplicity-induced variability" flag was assigned according to the difference between the "dc" and "ac" magnitudes, and according to the angular separation and magnitude difference of a double or multiple system. If this flag is set, the entry is not necessarily a physical variable, and not necessarily seen as variable in Hp. Multiplicity Data CCDM identifier (J2000.0): 13240+5456 Historical status of CCDM identifier: The system had been previously identified as double or multiple, as given in Annex 1 of the Hipparcos Input Catalog. Number of separate catalog entries with the same CCDM identifier: 1 Number of components into which the entry was resolved as a result of the Hipparcos observations and data reduction: 2 Further details of this system are given in one of the five (mutually exclusive) parts of the Hipparcos Double and Multiple Systems Annex. This entry has the following type of solution: component solutions; solutions are given for double and multiple stars in which the relative motions of the components can be described, to the precision of the observations, as a linear function of time. This condition is generally met for systems having orbital periods longer than several times the length of the Hipparcos observing interval (3.3 years), which applies to the majority of systems resolved into components by the Hipparcos instrument, or to systems not physically linked. Reliability of the double or multiple star solution: reliable solution. Component designations for the following data: Reference (brighter) component: A Subsidiary component: C Position angle (epoch J1991.25): 152° Angular separation (epoch J1991.25): 14.43 arcsec Standard error of separation: 0.01 arcsec Magnitude difference of components: 1.62 mag Standard error of magnitude difference: 0.03 mag Miscellaneous This is a "survey" star. Cross-identifications: HD identifier: HD 116656 DM identifier: BD +55 1598 V-I colour index used for the photometric processing of this entry: 0.07 mag Spectral type: A2V Source of spectral type: miscellaneous. Tycho 2 Catalog Data Tycho 2 Catalogue (E.Hog et al., 2000). Catalog number: TYC 3850-1385-1 Magnitude: 2.22 (Johnson V mag) B-V colour index: +0.054 mag Equatorial coordinates (epoch J2000.0, ICRS) RA: 13h 23m 55.5429s Dec: +54° 55' 31.302" Proper motion components (epoch J2000.0, ICRS) RA: +0.21091 arcsec/yr Dec: -0.02200 arcsec/yr Trigonometric parallax: 0.04173 arcsec Standard error of the parallax: 0.00061 arcsec Radial velocity: -5.6 km/sec Binary Star Orbit Data Fifth Catalog of Orbits of Visual Binary Stars (William I. Hartkopf, Brian D. Mason, & Charles E. Worley, Astrometry Department, U.S. Naval Observatory, 3450 Massachusetts Ave, NW, Washington, DC 20392, USA) WDS designation: MKT 8Aa Aitken double star catalog number: ADS 8891 Henry Draper catalog number: HD 116656 Hipparcos catalog number: HIP 65378 Magnitude of first component: 2.23 Orbital period: 0.05623 years Semi-major axis: 0.00983" Inclination: 60.5° Node: 106.0° Date of periastron passage: 1989.29898 Eccentricity: 0.5354 Longitude of periastron: 104.3° Grade of orbit: 1 - Definitive. Well-distributed coverage exceeding one revolution; no revisions expected except for minor adjustments. Position computed from this orbit: Position angle: 269.2° (J2000.0) Separation: 0.00" Notes: - Zeta UMa. The orbit of Aa is combined interferometric-spectroscopic (double-lined spectrum). A small magnitude difference (which would probably place the ascending node in the second quadrant) is uncertain. P =20.54 d, a = 0.0115". Star B (mag. 3.96, 15") is physical, and is itself an SB1, P = 175.55 d. This quadruple shares proper motion and parallax with 80 UMa (Alcor, Mag. 4 .0, 12', A5V) and with other members of the Ursa Major stream. - Visual orbit (including errors for inddividual elements) based on astrometry from Mark III interferometer. Additional spectroscopic data yield component masses, luminosities, radii, effective temperatures, and distance. - See Baize & Petit (1989) catalog of dooubles with variable component. - Orbit includes errors for individual eelements. - Combined solution for this resolved SBB2, yielding orbital parallaxes and component masses, as well as errors for individual elements. ------------------------------------------------------------------------------------------------- ************************************************************************************************ ------------------------------------------------------------------------------------------------- ALCOR ===== Summary Visual magnitude: 3.99 Spectral type: A5V SB Distance: 81.2 +/- 1.1 light years Luminosity: 12.7 +/- 0.4 x Sun's luminosity Position information for 29 ene 2003 11:53:41 (Julian day number 2452668.95395) Apparent RA (epoch of date): 13h 25m 21.17s Apparent Dec (epoch of date): +54° 58' 04.1" Constellation: Ursa Major Altitude: +31° 32' 28" Azimuth: 317° 43' 31" Transit: 5h 44m 34s The star is circumpolar and never rises or sets Names and Catalog Numbers Proper name: Alcor Flamsteed number: 80 Ursae Majoris Tycho catalog number: TYC 3850-1384-1 Hipparcos number: HIP 65477 Henry Draper number: HD 116842 DM number: BD +55 1603 PPM number: PPM 34021 SAO number: SAO 28751 Bright star number: HR 5062 Star Atlas Chart Numbers Herald-Bobroff Astroatlas, Chart C-11 Millennium Star Atlas, Charts 571-572 (Vol II) Sky Atlas 2000.0, Chart 2 Uranometria 2000 Chart 48, Vol 1 Yale Bright Star Catalog Data Preliminary Version of the Bright Star Catalogue, 5th Revised Edition. Dorrit Hoffleit, Department of Astronomy, Yale University, Wayne H. Warren Jr., ST Systems Corporation, National Space Science Data Center, NASA Goddard Space Flight Center (1991) Bright star catalog number: HR 5062 Position: RA (J2000.0): 13h 25m 13.5s Dec (J2000.0): +54° 59' 17" RA (B1900.0): 13h 21m 13.1s Dec (B1900.0): +55° 30' 32" Galactic coordinates (system II): Longitude: 112.77° Latitude: 61.47° Magnitude and spectral information: Magnitude: 4.01 [V on UBV (Johnson) system] B-V on Johnson system: +0.16 U-B on Johnson system: +0.08 R-I: +0.07 (on Johnson system) Spectral type: A5V Annual proper motion for J2000.0 on FK5 system: RA: +0.118" Dec: -0.016" Trigonometric parallax: +.045" Heliocentric radial velocity: -009 km/sec Radial velocity comments: Spectroscopic binary Projected rotational velocity (v sin i): 218 km/sec Variable star designation: 6238 Cross references to other catalogs: Durchmusterung: BD+55 1603 Henry Draper catalog: HD 116842 SAO catalog: SAO 28751 Remarks Double/multiple stars: CPM with HR 5054-5. Group membership: "Dipper Stars;" Sirius group; UMa stream; UMa moving cluster. Names: ALCOR; Saidak. Variability: Delta Sct. Hipparcos Catalog Data Hipparcos Catalogue (ESA SP-1200, 1997). Hipparcos Identifier/Proximity Flag Catalog number: HIP 65477 Proximity flag: None Descriptor V magnitude: 3.99 This star entry is variable at a level of <0.06 mag Source of V magnitude: Median Hipparcos magnitude (Hp), combined with information on the colour index (either V-I or Bt-Vt), in combination with the luminosity class. Main Mission Astrometric Data Equatorial coordinates (epoch J2000.0, ICRS) RA: 13h 25m 13.5379s Dec: +54° 59' 16.648" Standard errors of the equatorial coordinates (epoch J1991.25) RA: 0.00041 arcsec Dec: 0.00047 arcsec Trigonometric parallax: 0.04019 arcsec Standard error of the parallax: 0.00057 arcsec Proper motion components (epoch J1991.25, ICRS) RA: +0.20976 arcsec/yr Dec: -0.01694 arcsec/yr Standard errors of the proper motion components RA: 0.00075 arcsec Dec: 0.00051 arcsec Radial velocity: -8.9 km/sec Percentage of data that had to be rejected to obtain an acceptable astrometric solution (F1): 1% Goodness-of-fit parameter (F2): 1.28 Tycho Photometry and Colour Indices Mean magnitude in the Tycho photometric system, Bt: 4.225 Standard error of the Bt magnitude: 0.002 Mean magnitude in the Tycho photometric system, Vt: 4.023 Standard error of the Vt magnitude: 0.002 Johnson B-V colour index: 0.169 Standard error: 0.006 Source of B-V value: Ground-based observations. Cousins' V-I colour index: 0.19 Standard error: 0.03 Source of V-I value: Method C Main Mission Photometry Median magnitude in the Hipparcos photometric system, Hp: 4.0506 Standard error in median magnitude: 0.0008 mag Scatter of Hp observations: 0.008 mag Number of Hp observations: 122 Main Mission Variability Observed magnitude at maximum and minimum luminosities: Mag at max, Hp: 4.04 (5th percentile) Mag at min, Hp: 4.07 (95th percentile) Type of variability: unsolved variable. Entries are classified as "unsolved" if they do not fall into the other variability categories - this class also includes irregular or semi-irregular variables, and possible variables with amplitudes >=0.03 mag. Variability data for this star, such as periods, amplitudes, reference epochs, etc, compiled from the Hipparcos Hp data, along with associated ground-based data, are given in the table of "unsolved" variables in the Hipparcos Variability Annex. Multiplicity Data CCDM identifier (J2000.0): 13240+5456 Historical status of CCDM identifier: The system had been previously identified as double or multiple, as given in Annex 1 of the Hipparcos Input Catalog. Number of separate catalog entries with the same CCDM identifier: 1 Number of components into which the entry was resolved as a result of the Hipparcos observations and data reduction: 1 Miscellaneous This is a "survey" star. Cross-identifications: HD identifier: HD 116842 DM identifier: BD +55 1603 V-I colour index used for the photometric processing of this entry: 0.19 mag Spectral type: A5V SB Source of spectral type: updated after publication of the Hipparcos Input Catalogue. Tycho 2 Catalog Data Tycho 2 Catalogue (E.Hog et al., 2000). Catalog number: TYC 3850-1384-1 Magnitude: 3.99 (Johnson V mag) B-V colour index: +0.167 mag Equatorial coordinates (epoch J2000.0, ICRS) RA: 13h 25m 13.5363s Dec: +54° 59' 16.641" Proper motion components (epoch J2000.0, ICRS) RA: +0.20741 arcsec/yr Dec: -0.01830 arcsec/yr Trigonometric parallax: 0.04019 arcsec Standard error of the parallax: 0.00057 arcsec Radial velocity: -8.9 km/sec