PV Telescopii variable is a type of

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...

that is established in the ''

General Catalogue of Variable Stars The General Catalogue of Variable Stars (GCVS) is a list of variable stars in the Milky Way Galaxy. Its first edition, containing 10,820 stars, was published in 1948 by the Academy of Sciences of the USSR, edited by and Pavel Parenago. Second a ...

'' with the acronym PVTEL. This class of variables are defined as "helium supergiant Bp stars with weak hydrogen lines and enhanced lines of He and C". That is, the hydrogen spectral lines of these stars are weaker than normal for a star of stellar class B, while the lines of helium and carbon are stronger. They are a type of extreme helium star. The prototype for this category of variable is PV Telescopii, which undergoes small but complex luminosity variations and

radial velocity The radial velocity or line-of-sight velocity of a target with respect to an observer is the rate of change of the vector displacement between the two points. It is formulated as the vector projection of the target-observer relative velocity ...

fluctuations. The PV Tel stars are extremely hydrogen-deficient compared to other B-class stars and vary in luminosity on time scales ranging from a few hours to several years. As of 2008, there are twelve confirmed PV Tel variables in the ''General Catalogue of Variable Stars''. PV Telescopii variables are subdivided into three distinct types on the basis of

spectral type In astronomy, stellar classification is the classification of stars based on their spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the ...

: type I represents late B and A stars, type II represents O and early B, and type III represents F and G stars. The type III stars are always carbon-rich and hydrogen-deficient, while the type I and II stars do not necessarily have an excess of carbon. The hotter types pulsate more quickly than the cooler types.

List

The following list contains selected PV Telescopii variable that are of interest to amateur or professional astronomy. Unless otherwise noted, the given magnitudes are in the V-band.

Notes

References

{{Variable star topics