1634+706

Notes

PG 1634+706 is a bright quasar in Draco, about 5.7° NW of Zeta Draconis and close to the constellation Ursa Minor. PG 1634+706 has a redshift of z=1.337, which means a light travel-time of 8.6×10⁹ years! This is more than half way through the observable universe! So PG 1634+706 is one of the most luminous objects in the sky. As such, it was classified as a hyper luminous infrared galaxy (HyLIRG). The designation PG 1634+706 refers to the Palomar-Green Bright Quasar Survey (PG), where this object was discovered as a blue stellar object between 1976 und 1982. The new point source was immediately identified as a quasar by spectroscopy. As a blue stellar object it was also cataloged by the First Byurakan Spectral Sky Survey (FBS).

PG 1634+706 is a low amplitude variable object with a total range of only a few tenths of a magnitude. Visual observers need at least an 8- to 10-inch telescope to glimpse this stellar object. Even with large instruments, the quasar remains stellar. CCD observers, as well as visual observers, may use the comparison stars given above. No photometric sequence has been published to date. V-mag comparison stars A=14.23 and C=15.21 were calibrated from USNO A2.0 catalog, as part of the Frankfurt Quasar Monitoring project.

PG 1634+706 is located between Zeta (22) Draconis and the square of Ursa Minor, some 1.8° NNW of star 15 Draconis. An optical double of two 8-mag stars, only about 8´NW of the quasar (see charts above), is well suited to identify the correct position of PG 1634+706.

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Nearly 1° W of quasar PG 1634+706 we find a trio of moderately bright galaxies: NGC 6236 (12.6 m) and NGC 6248 (13.8 m) are both barred spirals, about 60 million light-years distant. NGC 6232 (13.4 m) is also a barred spiral, but is located in the cosmological background at approximately 200 million light-years distance. In addition, two deep sky showpieces are worth visiting: The first is NGC 6503, a bright, large and elongated Sc-spiral, some 6.3° to the east. The other one is famous "Cat´s Eye Nebula" (NGC 6543), some 8.5° E of PG 1634+706. This is a very bright and large planetary with a rich green-blue colour.

Far beyond our Milky Way, in this case about 1.5×10⁹ light-years, quasar MRK 876 is waiting for observers. This bright 15-mag object is located 5° SSE of PG 1634+706.
Another bright and variable quasi-stellar object is 3C 371, a bright 14-mag BL Lac object, some 8° E, at a distance of about 0.6×10⁹ light-years.

Only 5´ SE of NGC 6503 (see above), and 6.3° E of PG 1634+706, another variable BL Lac object shall not be missed: S4 1749+70, which is located at a distance of more than 6×10⁹ light-years. That´s quite a lot, so you may like to take a look !

Literature

Abramyan, G.B., Mikaelyan, A.M. 1994, Ap, 37, 224A; The First Byurakan Spectral Sky Survey. Blue Stellar Objects. IX.
Beyvers, G., Beyvers, C. 2001, SuW 9/01, 773; Quasare im Sechs- und im Achtzöller.
Hansen, T. 1991, Deep Sky Magazine 34, 32; The "Deepest" Deep Sky Objects.
Karge, S.; Helle Quasare für 8- bis 10-Zoll Teleskope. Ein Beobachtungsführer zur visuellen Beobachtung von Quasaren
und BL Lacertae Objekten; Frankfurt 2005.
Kirhakos, S.D., Sargent, W.S.W., et al. 1994, PASP, 106, 646; The HST Quasar Absorption-Line Key Project. VIII.
CCD Imaging of Hubble Space Telescope Quasar Fields.
Richards, G.T., Yanny, B., et al. 1997, PASP, 109, 39R; Quasar Photometry with the SDSS Monitor Telescope.
Schmidt, M., Green, R. 1983, ApJ, 269, 352; Quasar Evolution derived from the Palomar Bright Quasar Survey and other
complete Quasar Survey.
Spevak, J. 1994, Astronomy 7/94, 70; Oh say can you see?
Steinicke, W.; Katalog heller Quasare und BL Lacertae Objekte; Umkirch 1998.
Steinicke, W. 1999, Interstellarum 15, 42; Unbekannte Quasare für visuelle Beobachter.
Véron-Cetty, M.-P., Véron, P. 2001, A&A 374, 92; A Catalogue of Quasars and Active Nuclei: 10th edition.
Véron-Cetty, M.-P., Véron, P. 2003, A&A 412, 399; A Catalogue of Quasars and Active Nuclei: 11th edition.
Véron-Cetty, M.-P., Véron, P. 2006, A&A 455, 776; A Catalogue of Quasars and Active Nuclei: 12th edition.
Véron-Cetty, M.-P., Véron, P. 2010, A&A 518, 10; A Catalogue of Quasars and Active Nuclei: 13th edition.
Tytler, D., Fan, X.-M. 1992, ApJS, 79, 1; Systematic QSO Emission-Line Velocity Shifts and New Unbiased Redshifts.

Link:

Hamburg Quasar Monitoring

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Cross-Identifications	FBS 1634+706, IRAS 16347+7037, 1634+706 2E 1634.9+7037, RX J1634.4+7031, FBS 0908 1RXS J163429.2+703133, QSO B1634+7037 QSO J1634+7031, 2XMM J163428.9+703132
Equat. coordinates	RA 16 34 29.0 DE +70 31 33 (J2000)
Constellation	Draco
Type	QSO
Redshift (1)	z=1.337 (1) / z=1.334 (2)
Distance (2) (3)	3963 Mpc
Total mag range (mv) (4)	14.2 - 14.7
Catalog Magnitude (1)	15.27p
Absolute Magnitude (1)	-29.7 M_B
Light Travel-Time (2)	8.633 × 10⁹ yrs

star	V
A	14.23 (0.05)
B	14.70 (0.05)
C	15.21 (0.05)
D	16.10 (0.05)