(array of four telescopes sharing RV spectrograph)
MARVEL (for Mercator Array for Radial Velocities) is an array
under construction of four 0.8-m visible lighttelescopes all
attached to an RVspectrograph designed to measure
radial velocities down to 1 m/s.
Fiber from each telescope leads to the spectrograph, each telescope
measuring an individual star, or more than one telescope
used together gather more light to measure a fainter star.
MARVEL is located at Roque de los Muchachos Observatory (ORM) as an extension of the
Mercator Telescope facility, termed Mercator Observatory.
The four telescopes are "commercial off-the-shelf",
reducing the cost of the telescopes, and gaining some
benefits, among them, the ability to carry out
simultaneous such observations.
Plans are for first light by the end of 2025.
Note that the similar name, MARVELS, was used for an SDSS-IIIsurvey that searched for extra-solar planets using
the RV method, the survey having a purpose-built spectrograph,
likely sometimes referred to as the MARVELS spectrograph.