Observing the Sky from 40°N/Tables

The tables below make use of the following symbols:

The best view of the star / the object is with binoculars. The star / the object is visible with binoculars, but the best view is with small telescopes. The star / the object is visible only with telescopes.

The 40 brightest stars
Column Headings
 * Proper name: the name of the star.
 * Catalogue number: the Bayer designation of the star, a system developed by Henry Draper in 1603.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the star is located.
 * Magn.: the apparent magnitude of the star.
 * Dist.(ly): approximate distance of the star, expressed in light-years.
 * Spectral type: the spectral class, the luminosity class and peculiarity.
 * Notes: notable notes about the star.



Double stars
Column Headings
 * Name: the Bayer or Flamsteed designation of the star.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the star is located.
 * Mag. A: the apparent magnitude of the primary component.
 * Mag. B: the apparent magnitude of the secondary component.
 * Sep.: the separation between the components, expressed in seconds of arc.
 * Pos. angle: the position angle, counted in degrees from north (0°) through east (90°), south (180°), and west (270°). The position angles are for the component B with respect to the component A.
 * Colours: the colours of the two components of the system, based on their spectral type.
 * Notes: notable notes about the star system, membership in star clusters, physic of the system.
 * Common name: the proper name of the star system.



Variable stars
Column Headings
 * Name: the Bayer, Flamsteed or variable designation of the star.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the star is located.
 * Min.: the apparent magnitude at maximum brightness.
 * Max.: the apparent magnitude at minimum brightness.
 * Period (days): the average period of variation in days.
 * Type: the type of variability.
 * Spectrum: the spectral class of the star. In eclypsing binaries, the spectra of both the components are indicated; in pulsating variables, the variation of the spectrum is showed.
 * Common name: the proper name of the star.



Open clusters
Column Headings
 * Name: the cluster’s name as plotted on the maps.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the cluster is located.
 * Diam.: apparent diameter expressed in minutes of arc.
 * Magn.: the apparent magnitude of the cluster; a symbol “:” after this value means an approximation.
 * Dist.(pc): approximate distance of the cluster, expressed in parsec. To obtain the distance in light-years, multiply by 3.26.
 * Galactic arm: the spiral arm of the Milky Way in which the cluster is located.
 * Type: descriptive type based on the system developed by R. J. Trumpler in 1930. It is composed by three parts:
 * Concentration
 * I.  Detached; strong concentration toward centre.
 * II. Detached; weak concentration toward centre.
 * III. Detached; no concentration toward centre.
 * IV. Not well detached from surrounding star field.
 * Range in brightness
 * 1. Small range in brightness.
 * 2. Moderate range in brightness.
 * 3. Large range in brightness.
 * Richness
 * p  Poor (less than 50 stars).
 * m Moderately rich (50 to 100 stars).
 * r   Rich (more than 100 stars).
 * Notes: notable notes about the cluster, membership in OB associations, nebulosity.
 * Common name: the proper name of the cluster.



Globular clusters
Column Headings
 * Name: the cluster’s name as plotted on the maps.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the cluster is located.
 * Diam.: apparent diameter expressed in minutes of arc.
 * Magn.: the apparent magnitude of the cluster; a symbol “:” after this value means an approximation.
 * Dist.(pc): approximate distance of the cluster, expressed in parsec. To obtain the distance in light-years, moltiply for 3.26.
 * Class: concentration class of the globular cluster based on the system developed by H. Shapley in 1927. The values range from 1 to 12; the smaller is the number, the higher is the concentration of stars toward the centre of the cluster.
 * Notes: notable notes about the cluster, strong X-ray sources.
 * Common name: the proper name of the cluster.



Bright nebulae
Column Headings
 * Name: the nebula’s name as plotted on the maps.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the nebula is located.
 * Diam.: apparent diameter expressed in minutes of arc.
 * Magn.: the apparent magnitude of the nebula; a symbol “:” after this value means an approximation.
 * Dist.(pc): approximate distance of the nebula, expressed in parsec. To obtain the distance in light-years, moltiply for 3.26.
 * Galactic arm: the spiral arm of the Milky Way in which the nebula is located.
 * Type: the type of the nebula:
 * H II regions are nebulae with an high rate of ionized hydrogen emitting light.
 * Reflection nebulae are clouds of gas and dust illuminated by a nearby star.
 * SNR is a supernova remnant, a bubble of filamentary gas expelled after the explosion of a supernova.
 * Notes: notable notes about the nebula, membership in OB associations.
 * Common name: the proper name of the nebula.



Planetary nebulae
Column Headings
 * Name: the nebula’s name as plotted on the maps.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the nebula is located.
 * Diam.: apparent diameter expressed in seconds of arc.
 * Magn.: the apparent magnitude of the nebula; a symbol “:” after this value means an approximation.
 * Dist.(pc): approximate distance of the nebula, expressed in parsec. To obtain the distance in light-years, moltiply for 3.26.
 * Galactic arm: the spiral arm of the Milky Way in which the nebula is located.
 * Type: the aspect of the nebula, according to the Vorontsov-Velyaminon system:
 * 1. Stellar image.
 * 2. Smooth disk (a, brighter toward the centre; b, uniform brightness; c, traces of ring structure).
 * 3. Irregular disk (a, very irregular brightness distribution; b, traces of ring structure).
 * 4. Ring structure.
 * 5. Irregular form (similar to a diffuse nebula).
 * 6. Anomalous form.
 * Magn. of the central star: the apparent magnitude of the star that originates the nebula.
 * Common name: the proper name of the nebula.



Galaxies
Column Headings
 * Name: the galaxy’s name as plotted on the maps.
 * RA(2000.0) and Dec.: right ascension and declination, referred to the 2000.0 equinox.
 * Const.: the constellation in which the galaxy is located.
 * Diam.: apparent diameter expressed in minutes of arc.
 * Magn.: the apparent magnitude of the galaxy; a symbol “:” after this value means an approximation.
 * Dist.(Mpc): approximate distance of the galaxy, expressed in megaparsec (millions of parsec). To obtain the distance in light-years, moltiply *for 3,260,000.
 * Type: the Hubble type of the galaxy, as described in the introduction.
 * Nuclear class: the nuclear class according to the system developed by G. de Vancouleurs in 1976; numbers from 1 to 5 indicates the increasing *of the luminosity of the nucleus.
 * Common name: the proper name of the galaxy.