Van Biesbroeck 8b

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Van Biesbroeck 8b is a brown dwarf star, orbiting the star Van Biesbroeck 8 in the constellation Ophiuchus.

When discovered in 1984,[1] it was thought to be a planet.[citation needed] With a mass up to fifty times that of Jupiter, it was classified as a brown dwarf star, a gaseous object too large to be a planet yet with not enough mass for stellar ignition.

It was not observed visually, either by human eye or instruments,[1] but rather through astrometry (the measurement of very small perturbations in a star's position due to the gravitational influence of another body) and infrared speckle interferometry.

According to The Internet Encyclopedia of Science,[1] it is now generally accepted that VB 8b does not exist. Van Biesbroeck 8b seemed to abruptly vanish when later attempts to observe its gravitational pull on Van Biesbroeck 8 failed. It is currently unknown whether the object ever existed. It is difficult to re-confirm its existence or decide that there were errors in the original astrometric measurements.

Since the original announcement, dozens of other extrasolar planets have been discovered and confirmed as genuine, including the first one to be photographed visually, in 2005, around the star GQ Lupi. That object, presently designated GQ Lupi b, has yet to be given a permanent name.

[edit] References

  1. ^ a b c David Darling. Van Biesbroeck 8. Internet Encyclopedia of Science. “In 1984, independent announcements were made of the discovery of an unseen companion, van Biesbroeck 8b (VB 8b), which was suspected of being a brown dwarf. The claims were made by Robert Harrington of the US Naval Observatory, based on astrometric observations, and by Donald McCarthy and colleagues at the University of Arizona, from a study using infrared speckle interferometry. Despite this persuasive double sighting, however, subsequent observations of greater sensitivity failed to uncover any further trace of the object. As a result, it is now generally accepted that VB 8b does not exist.”