Summary of Articles (William Matzko)

The planet orbiting VB 10 was originally “discovered” using the Stellar Planet Survey (STEPS) program via the astrometric method. Their data were taken over a period of 9 years and made use of 15 reference stars. Two different sets of reference stars were used as a check to ensure that their results are not just a product of their chosen reference stars. The authors constructed a periodogram of VB 10, as well as the reference stars, and analyzed them using the Lomb-Scargle algorithm. They computed a False Alarm Probability (FAP) for a variety of periods and found that the smallest FAP occurred for a 0.74 year period (with a 3E-3 % chance of being false). None of the reference stars show a significant FAP at 0.74 years. They also fit their data (as well as existing RV data) to a Keplarian model. This model showed that the 0.74 year period is indeed the best fit. This fit also helped to infer possible planet masses, of which the most likely of about 6.4 Jupiter masses. This was refuted later by near infrared radial velocity measurements over a period of 0.61 years. The data they obtained were constant, within their uncertainty. Their precision (~10 m/s) should have been more than sufficient to detect the claimed 6.4 Jupiter mass planet. That indicates that there is in fact no planet orbiting VB 10 (else they would have detected some RV signal). 

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