CD-27 14659 / HR 7722

Its designation as CD-27 14659 came from a visual survey of southern stars begun in 1892 at the Astronomical Observatory of Cordoba in Argentina under the direction of its second director John M. Thome (1843-1908). Thome died before the completion of this southern sky atlas in 1914, when 578,802 stars from declination -22° to -90° were published as the Cordoba Durchmusterung ("Survey"). The "CD" is an extension of an older catalogue by Friedrich Wilhelm August Argelander (1799-1875) in 1863 on the position and brightness of 324,198 stars between +90° and -2° declination that were measured over 11 years from Bonn, Germany, made with his assistants Eduard Schönfeld (1828-1891) and Aldalbert Krüger (1832-1896), which became famous as the Bonner Durchmusterung ("Bonn Survey") abbreviated as BD. The BD and CD were greatly expanded and extended into the modern age of photographic surveys with the subsequent creation of the Cape Photographic Durchmusterung from South Africa.

As a relatively bright star in Earth's night sky, Star A is catalogued as Harvard Revised (HR) 7722, a numbering system derived from the 1908 Revised Harvard Photometry catalogue of stars visible to many Humans with the naked eye. The HR system has been preserved through its successor, the Yale Bright Star Catalogue -- updated and expanded through the hard work of E. Dorrit Hoffleit and others. HR 7722 is also listed as HD 192310 in the Henry Draper (1837-82) Catalogue with extension (HDE), a massive photographic stellar spectrum survey carried out by Annie Jump Cannon (1863-1941) and Edward Charles Pickering (1846-1919) from 1911 to 1915 under the sponsorship of a memorial fund created by Henry's wife, Anna Mary Palmer. (More discussion on star names and catalogue numbers is available from Alan MacRobert at Sky and Telescope and from Professor James B. Kaler's Star Names.)

The Star

CD-27 14659 is a main-sequence orange-red dwarf star of spectral and luminosity type K0-3 V. It may have around 87 percent of Sol's mass, 84 percent of its diameter (Johnson and Wright, 1983, page 695), and 33 percent of its luminosity. It appears to be 78 to 91 percent as enriched as Sol in elements heavier than hydrogen ("metals") based on its abundance of iron (Cayrel de Strobel et al, 1991, page 307). The star may have a spectroscopic companion star. CD-27 14659 is a Catalogue of Suspected Variable Star designated as CSV 101960 and a New Suspected Variable star designated as NSV 12933. Useful star catalogue numbers for CD-27 14659 include: HR 7722, Gl 785, Hip 99825, HD 192310, CP(D)-27 6972, SAO 189065, LHS 488, LTT 8009, LFT 1535, and LPM 731.

CD-27 14659 B?

According to the Astronomiches Rechen-Institut at Heidelberg's ARICNS entry for Gl 785, CD-27 14659 is suspected of having a spectroscopic companion star.

Hunt for Substellar Companions

The distance from CD-27 14659 where an Earth-type planet would be "comfortable" with liquid water is centered around only 0.575 AU -- between the orbital distances of Mercury and Venus in the Solar System. An Earth-type in such a water-zone orbit would probably would have a period of around 170 days or close to half an Earth year. Astronomers are hoping to use NASA's Terrestrial Planet Finder (TPF) and the ESA's Darwin planned groups of observatories to search for a rocky inner planet in the so-called "habitable zone" (HZ) around CD-27 14659. As currently planned, the TPF will include two complementary observatory groups: a visible-light coronagraph to launch around 2014; and a "formation-flying" infrared interferometer to launch before 2020, while Darwin will launch a flotilla of three mid-infrared telescopes and a fourth communications hub beginning in 2015.