HW4-Q3

Summary of two articles concerning VB 10.

VB 10 is ultra-cool dwarf star that was reportedly, by Pravdo and Shaklan, to have the first extrasolar giant planet orbiting with a mass of 6.4 (+2.6,−3.1) Jupiter-masses (MJ) and an orbital period of 0.744 (+0.013,−0.008) yrs. This discovery was obtained with the Stellar Planet Survey (STEPS) program over a span of 9 years. They researchers used the astrometry method using a variety of reference stars. They attempted to provide explanations for arguments that might arise after their discovery, specifically, radial velocity measurements. They declared the radial velocity observations obsolete due to their insufficient precision measurement of 1.1-1.5 kms-1 . However, they were unsuccessful in proving the existence of the star due to an article published by Bean et al. which refuted their discovery through radial velocity analysis of the star on the Very Large Telescope with the precision of the measurements being  10 ms-1 . Thus, the planet lost its credibility and was scraped from existence. It now exists only in memory among the other rejected planets. 

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