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Exoplanet Detection JS: Radial Velocity Method Documents

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Main Document

Exoplanet Detection JS: Radial Velocity Method 

written by Mario Belloni

The Exoplanet Detection JS: The Radial Velocity Method model simulates the detection of exoplanets by using the radial velocity method and the Doppler effect. In this simulation the exoplanet orbits the star (sun-sized) in circular motion via Kepler's third law.  The radial velocity of the star is determined from the velocity of the exoplanet.  This velocity is then used to calculate the Doppler shift of the Fraunhofer lines of the star.  In practice it is the Doppler shift of the Fraunhofer lines of the star that are detected and from this the radial velocity is inferred.  From this the mass and orbital period and average exoplanet-star separation are determined.  In the simulation the star-exoplanet system is shown as seen from Earth (edge on view) and from space (overhead view), and with the star and exoplanet sizes not shown to the scale of the orbit.  In addition, the Fraunhofer lines are shown.  The radial velocities of stars are such that the Doppler shifts are small, to compensate you may snap to the Na line and use the right-hand side slider to zoom in on that line to see wavelength shift.  The mass of the exoplanet (relative to the mass of Jupiter), the average star-exoplanet separation (in AU), and the inclination of the system relative to Earth can be changed.

The simulation is in JavaScript and will run on any device and operating system with a JavaScript enabled browser.

Published October 12, 2019
Last Modified October 12, 2019

This file is included in the full-text index.

Supplemental Documents

Exoplanet Detection JS: 51 Pegasi b 

This is a version of the Exoplanet Detection JS: Radial Velocity Method simulation that depicts the 51 Pegasi b system, for which Michel Mayor and Didier Queloz used the radial velocity method and the Doppler effect to detect the first exoplanet. For this discovery, Mayor and Queloz were awarded the 2019 Nobel Prize in Physics. The mass of the exoplanet is 0.46 the mass of Jupiter and the average star-exoplanet separation is 0.05 AU.

Released under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 license.

Published October 12, 2019
Last Modified October 12, 2019

This file is included in the full-text index.

Source Code Documents

Exoplanet Detection JS: Radial Velocity Method Source Code 

Source Code for the Exoplanet Detection JS: Radial Velocity Method program.

Released under a This material is released under the Creative Commons Attribution-Noncommercial-Share Alike 3.0.

Published October 12, 2019
Last Modified October 12, 2019