3C 249.1

3C 249.1 is a Seyfert galaxy located in the constellation Draco.

3C 249.1
Observation data (Epoch J2000)
ConstellationDraco
Right ascension 11h 04m 13.8777s[1]
Declination+76° 58′ 58.170″[1]
Redshift0.311500[2]
Distance (comoving)1,194 megaparsecs (3.89×109 ly) h−1
0.73
[2]
TypeSy1, Rad, QSO, X, IR, G, BH?, AG?, UV, gam[1]
QSO[2]
Apparent magnitude (V)15.72[1]
Other designations
LEDA 2821945, 4C 77.09, QSO B1100+773, PG 1100+772
See also: Quasar, List of quasars

References

  1. ^ a b c d "Query : 3C 249.1". Simbad. Centre de Données astronomiques de Strasbourg. Retrieved 2 June 2015.
  2. ^ a b c "NED results for object 3C 249.1". NASA/IPAC Extragalactic Database. Retrieved 2 June 2015.

External links

Coordinates: Sky map 11h 04m 13.687s, +76° 58′ 58.02″

7 Draconis

7 Draconis, also named Tianyi (or) , is a single star in the northern circumpolar constellation of Draco. It is visible to the naked eye as a faint orange-hued star with a stellar classification of 5.43. Based upon an annual parallax shift of 4.16 mas as seen from the Earth, the star is located approximately 780 light-years from the Sun.

This is an evolved giant star with a stellar classification of K5 III. The measured angular diameter of this star, after correction for limb darkening, is 2.61±0.03 mas. At its estimated distance, this yields a physical size of about 67 times the radius of the Sun. It is radiating about 1,024 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,945 K.

8 Draconis

8 Draconis, formally named Taiyi , is a single star in the northern circumpolar constellation of Draco. Based upon an annual parallax shift of 34.14 mas as seen from the Earth, the star is located approximately 96 light-years from the Sun. It is moving further away with a heliocentric radial velocity of +9 km/s, having come within 40.6 ly some 2.6 million years ago.This is an F-type main-sequence star with a stellar classification of F1VmA7(n). It is a Gamma Doradus variable star with a brightness variation of about one tenth of a magnitude. 8 Dra has a relatively high rate of rotation, showing a projected rotational velocity of 120 km/s. The star has 1.56 times the mass of the Sun and 1.50 times the Sun's radius. It is radiating 5.75 times the Sun's luminosity from its photosphere at an effective temperature of 7,129 K. An infrared excess has been detected at wavelengths of 24 and 70μm, which suggests the presence of a circumstellar disk orbiting the star.

Alruba

Alruba , designated HD 161693 and HR 6618, is a star in the northern circumpolar constellation of Draco. Based on parallax measurements obtained during the Gaia mission, it is about 457 light-years (140 parsecs) distant from the Sun.

Lambda Draconis

Lambda Draconis (λ Draconis, abbreviated Lam Dra, λ Dra), also named Giausar , is a solitary, orange-red star in the northern circumpolar constellation of Draco. It is visible to the naked eye with an apparent visual magnitude of +3.85. Based upon an annual parallax shift of 9.79 mas as seen from the Earth, the star is located around 333 light years from the Sun.

This is an evolved red giant star on the asymptotic giant branch with a stellar classification of M0III-IIIa Ca1. It is a suspected slow irregular variable with a periodicity of roughly 1,100 days. The measured angular diameter, after correction for limb darkening, is 6.43±0.07 mas. At the estimated distance of the star, this yields a physical size of about 53 times the radius of the Sun. It has an estimated 1.7 times the mass of the Sun and is radiating 834 times the solar luminosity from its photosphere at an effective temperature of 3,958 K.

Pi Draconis

Pi Draconis, Latinized from π Draconis, is a solitary star in the northern circumpolar constellation of Draco. It is visible to the naked eye with an apparent visual magnitude of 4.59. Based upon an annual parallax shift of 14.25 mas as measured from Earth, it is located around 229 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.063±0.10 due to interstellar dust.With an age of 350 million years, this is an A-type star of stellar classification A2 IIIs, where the luminosity class of III typically indicates an evolved giant star and the 's' means the spectrum displays sharp absorption lines. It is a candidate Am star, meaning there are some chemical peculiarities. The measured angular size is 0.427±0.062 arc seconds. At the estimated distance of Pi Draconis, this yields a physical size of about 3.2 times the radius of the Sun. It has about 2.70 times the mass of the Sun and is radiating 60 times the solar luminosity from its photosphere at an effective temperature of 9,125 K.

Psi2 Draconis

Psi2 Draconis is a solitary giant star in the northern circumpolar constellation of Draco, also designated 34 Draconis. It lies about a degree east of the brighter Psi1 Draconis.

Psi2 Draconis has an apparent magnitude of 5.45. and is located around 287 parsecs (940 ly) away. It is a white giant of spectral type F2III+, a star that has used up its core hydrogen, cooled, and expanded away from the main sequence. It is now over 500 times as luminous as the sun.

Rho Draconis

Rho Draconis (ρ Draconis) is a solitary star in the northern circumpolar constellation of Draco. It is faintly visible to the naked eye with an apparent visual magnitude is 4.52. Based upon an annual parallax shift of 7.61 mas as measured from Earth, it is located around 429 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.027 due to interstellar dust.With a stellar classification of K3 III, Rho Draconis is a normal giant star that is past the first dredge-up phase of its post-main sequence evolution. It has the peculiar spectrum of a CN star, showing abnormal line strengths for cyanogen and calcium. The star has expanded to around 28 times the Sun's radius and it is radiating 402 times the solar luminosity from its photosphere at an effective temperature of 4,370 K.

Tau Draconis

Tau Draconis, Latinized from τ Draconis, is an astrometric binary star system in the northern circumpolar constellation of Draco. The star is faintly visible to the naked eye, having an apparent visual magnitude of 4.45. Based upon an annual parallax shift of 22.28 mas as measured from Earth, it is located around 146 light years from the Sun. Its proper motion is propelling it across the sky at the rate of 0.176 arc seconds per year.This is a K-type giant star with a stellar classification of K2 III:, where the semi-colon indicates some uncertainty about its spectral value. It is considered metal-rich star and is past the first dredge-up phase of its post-main sequence evolution, although it shows under-abundances of carbon and oxygen in its spectrum. The star has 1.25 times the mass of the Sun and is an estimated 6.48 billion years old. It is radiating 48 times the solar luminosity from its enlarged photosphere at an effective temperature of 4,413 K.

Thuban

Thuban , designation Alpha Draconis (α Draconis, abbreviated Alpha Dra, α Dra), is a star (or star system) in the constellation of Draco. A relatively inconspicuous star in the night sky of the Northern Hemisphere, it is historically significant as having been the north pole star from the 4th to 2nd millennium BC.

Even though Johann Bayer gave Thuban the designation Alpha, its apparent magnitude of 3.65 means it is 3.7 times fainter than the brightest star in the constellation, Gamma Draconis (Eltanin), whose apparent magnitude is 2.24.

Upsilon Draconis

Upsilon Draconis (υ Dra) is a binary star system in the northern circumpolar constellation of Draco. It is faintly visible to the naked eye with an apparent visual magnitude of 4.83. Based upon an annual parallax shift of 9.48 mas as measured from Earth, it is located around 340 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.02 due to interstellar dust.In Chinese, 紫微左垣 (Zǐ Wēi Zuǒ Yuán), meaning Left Wall of Purple Forbidden Enclosure, refers to an asterism consisting of υ Draconis, ι Draconis, η Draconis, ζ Draconis, θ Draconis, 73 Draconis, γ Cephei and 23 Cassiopeiae. Consequently, the Chinese name for ζ Draconis itself is 紫微左垣五 (Zǐ Wēi Zuǒ Yuán wu, English: the Fifth Star of Left Wall of Purple Forbidden Enclosure.), representing 少弼 (Shǎobì), meaning The Second Minister.

This is a single-lined spectroscopic binary star system with an orbital period of 258.48 days and an eccentricity of 0.21. The primary, component A, is an evolved K-type giant star with a stellar classification of K0 III. It is a suspected barium star, which may indicate the orbiting companion, component B, is a white dwarf star.The measured angular diameter of the primary, after correction for limb darkening, is 1.69±0.02 mas. At the estimated distance of Upsilon Draconis, this yields a physical size of about 19 times the Sun's radius. It is about 1.37 billion years old with an estimated 2.05 times the mass of the Sun. The star is radiating 2.23 times the solar luminosity from its photosphere at an effective temperature of 4,561 K.

List of notable Seyfert galaxies
Seyfert 1
Seyfert 2

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