Editing Telescopium (section)

===Stars===
{{See also|List of stars in Telescopium}}
Within the constellation's borders, there are 57 stars brighter than or equal to [[apparent magnitude]] 6.5.{{efn|1=Objects of magnitude 6.5 are among the faintest visible to the unaided eye in suburban-rural transition night skies.{{sfn|The Bortle Dark-Sky Scale}}}}{{sfn|Ridpath, Constellations – 2}} With a magnitude of  3.5, [[Alpha Telescopii]] is the brightest star in the constellation. It is a blue-white [[subgiant]] of [[Stellar classification#Spectral types|spectral type]] B3IV which lies around 250 [[light-year]]s away.{{sfn|Kaler, ''Alpha Telescopii''}} It is radiating nearly 800 times the [[solar luminosity|Sun's luminosity]], and is estimated to be 5.2±0.4 times as massive and have 3.3±0.5 times the Sun's radius.{{sfn|Hubrig|Briquet|De Cat|Schöller|2009}} Close by Alpha Telescopii are the two blue-white stars sharing the designation of [[Delta Telescopii]]. Delta¹ Telescopii is of spectral type B6IV and apparent magnitude 4.9,{{sfn|SIMBAD HR 6934}} while Delta² Telescopii is of spectral type B3III and magnitude 5.1.{{sfn|SIMBAD HR 6938}} They form an [[Double star|optical double]],{{sfn|Ridpath|Tirion|2007|pp=242–43}} as the stars are estimated to be around 710 and 1190 light-years away respectively.{{sfn|van Leeuwen|2007}} The faint (magnitude 12.23) [[Gliese 754]], a [[red dwarf]] of spectral type M4.5V, is one of the nearest 100 stars to Earth at 19.3 light-years distant.{{sfn|SIMBAD LHS 60}} Its [[Orbital eccentricity|eccentric orbit]] around the Galaxy indicates that it may have originated in the Milky Way's [[thick disk]].{{sfn|Innanen|Flynn|2010}}

At least four of the fifteen stars visible to the unaided eye are [[Giant star|orange giants]] of [[Stellar classification#Class K|spectral class K]].{{sfn|Bagnall|2012|pp=434–35}} The second brightest star in the constellation—at apparent magnitude 4.1—is [[Zeta Telescopii]], an orange subgiant of spectral type K1III-IV.{{sfn|Gray et al.|2006}} Around 1.53 times as massive as the Sun, it shines with 512 times its [[luminosity]].{{sfn|Liu et al. 2007}} Located 127 light years away from Earth, it has been described as yellow{{sfn|Ridpath|Tirion|2007|pp=242–43}} or reddish in appearance.{{sfn|Streicher|2009|pp=168–71}} [[Epsilon Telescopii]] is a [[binary star]] system:{{sfn|Ferreira|2009|pp=166–67}} the brighter component, Epsilon Telescopii A, is an orange [[giant star|giant]] of spectral type K0III with an [[apparent magnitude]] of +4.52,{{sfn|SIMBAD Epsilon Telescopii}} while the 13th magnitude companion, Epsilon Telescopii B, is 21 [[arcsecond]]s away from the primary, and just visible with a 15&nbsp;cm [[aperture]] telescope on a dark night.{{sfn|Ferreira|2009|pp=166–67}} The system is 417 light-years away.{{sfn|McDonald et al. 2012}} [[Iota Telescopii]] and [[HD 169405]]—magnitude 5 orange giants of spectral types K0III and K0.5III respectively{{sfn|SIMBAD Iota Telescopii}}{{sfn|SIMBAD HD 169405}}—make up the quartet.{{sfn|Bagnall|2012|pp=434–35}} They are around 370 and 497 light-years away from the Sun respectively.{{sfn|McDonald et al. 2012}} Another ageing star, [[Kappa Telescopii]] is a [[giant star#Yellow giants|yellow giant]] with a spectral type G9III and apparent magnitude of 5.18.{{sfn|SIMBAD Kappa Telescopii}} Around 1.87 billion years old, this star of around 1.6 solar masses has swollen to 11 times the Sun's diameter.{{sfn|da Silva et al. 2006}} It is approximately 293 light-years from Earth, and is another optical double.{{sfn|Ferreira|2009|pp=166–67}}

[[Xi Telescopii]] is an [[irregular variable]] star that ranges between magnitudes 4.89 and 4.94.{{sfn|AAVSO NSV 12783}} Located 1079 light-years distant, it is a [[red giant]] of spectral type M2III that has a diameter around 5.6 times the Sun's,{{sfn| Pasinetti Fracassini et al. 2001}} and a luminosity around 2973 times that of the Sun.{{sfn|McDonald et al. 2012}} Another irregular variable, [[RX Telescopii]] is a [[red supergiant]] that varies between magnitudes 6.45 and 7.47,{{sfn|AAVSO RX Telescopii}} just visible to the unaided eye under good viewing conditions. [[BL Telescopii]] is an [[Algol variable|Algol]]-like [[eclipsing binary]] system that varies between [[apparent magnitude]]s 7.09 and 9.08 over a period of just over 778 days (2 years 48 days).{{sfn|AAVSO BL Telescopii}} The primary is a [[yellow supergiant]] that is itself intrinsically variable.{{sfn|Zsoldos|1994}} Dipping from its baseline magnitude of 9.6 to 16.5,{{sfn|AAVSO RS Telescopii}} [[RS Telescopii]] is a rare [[R Coronae Borealis variable]]—an extremely hydrogen-deficient [[supergiant]] thought to have arisen as the result of the merger of two [[white dwarf]]s; fewer than 100 have been discovered as of 2012.{{sfn|Tisserand|2012}} The dimming is thought to be caused by carbon dust expelled by the star. As of 2012, four dimmings have been observed.{{sfn|Tisserand|2012}} [[PV Telescopii]] is a class B-type (blue) [[extreme helium star]] that is the prototype of a class of variables known as [[PV Telescopii variable]]s. First discovered in 1952, it was found to have a very low level of hydrogen. One theory of its origin is that it is the result of a merger between a helium- and a carbon-oxygen white dwarf. If the combined mass does not exceed the [[Chandrasekhar limit]], the former will accrete onto the latter star and ignite to form a supergiant. Later this will become an extreme helium star before cooling to become a white dwarf.{{sfn|Pandey 2006}}

[[File:HR 6819.jpg|thumb|An artist's depiction of the orbits of the hierarchical triple star system [[HR 6819]], with the inferred black hole (red orbit) in the inner binary]]
While [[RR Telescopii]], also designated ''Nova Telescopii 1948'', is often called a [[Nova#Development|slow nova]], it is now classified as a [[symbiotic nova]] system composed of an M5III pulsating [[red giant]] and a white dwarf; between 1944 and 1948 it brightened by about 7 magnitudes before being noticed at apparent magnitude 6.0 in mid-1948.{{sfn|Robinson 1975}} It has since faded slowly to about apparent magnitude 12.{{sfn|Light Curve Generator}} [[QS Telescopii]] is a binary system composed of a white dwarf and [[main sequence]] donor star, in this case the two are close enough to be [[Tidal locking|tidally locked]], facing one another. Known as [[Polar (cataclysmic variable star)|polars]], material from the donor star does not form an [[accretion disk]] around the white dwarf, but rather streams directly onto it.{{sfn|Gerke|2006}} This is due to the presence of the white dwarf's strong [[magnetic field]].{{sfn|Traulsen|2011}}

Although no star systems in Telescopium have confirmed planets, several have been found to have [[brown dwarf]] companions. A member of the 12-million-year-old [[Beta Pictoris moving group]] of stars that share a [[common proper motion]] through space,{{sfn|Smith 2009}} [[Eta Telescopii]] is a young [[A-type main-sequence star|white main sequence star]] of magnitude 5.0 and spectral type A0V.{{sfn|SIMBAD Eta Telescopii}} It has a [[debris disk]] and brown dwarf companion of spectral type M7V or M8V that is between 20 and 50 times as massive as Jupiter.{{sfn|Smith 2009}} The system is complex, as it has a common proper motion with (and is gravitationally bound to) the star [[HD 181327]], which has its own debris disk.{{sfn|Neuhäuser 2011}} This latter star is a [[F-type main-sequence star|yellow-white main sequence star]] of spectral type F6V of magnitude 7.0.{{sfn|SIMBAD HD 181327}} [[PZ Telescopii]] is another young star with a debris disk and substellar brown dwarf companion, though at 24 million years of age appears too old to be part of the Beta Pictoris moving group.{{sfn|Jenkins 2012}} [[HD 191760]] is a yellow subgiant—a star that is cooling and expanding off the [[main sequence]]—of spectral type G3IV/V. Estimated to be just over four billion years old, it is slightly (1.1 to 1.3 times) more massive as the Sun, 2.69 times as luminous, and has around 1.62 times its radius. Using the [[High Accuracy Radial Velocity Planet Searcher]] (HARPS) instrument on the [[ESO 3.6 m Telescope]], it was found to have a brown dwarf around 38 times as massive as Jupiter orbiting at an average distance of 1.35 AU with a period of 505 days. This is an unusually close distance from the star, within a range that has been termed the [[brown-dwarf desert]].{{sfn|Jenkins 2009}}