The MEarth project is an astronomical survey that observes nearby M-type dwarf stars in the search of Earth-like planets outside of our solar system. The project is located in a single enclosure at the Fred Lawrence Whipple Observatory on Mount Hopkins.

 

MEarth consists of 8 identical telescopes, each with a 16 inch primary mirror. This light from stars is captured by CCDs that measure the brightness of these stars over long periods of time. Astronomers are looking for variation in the brightness of these stars that could indicate the blocking of light from the star by means of an orbiting planet. The multiple telescopes are used to observe many stars at any one point.

 

These telescopes are not controlled manually, but robotically by pre-set specifications. This means that they can take hundreds of images every night.

 

MEarth has made many discoveries since astronomers have been using the array. In 2009, the project discovered its first exoplanet; GJ1214b, which is located just 40 lightyears away from us. This makes it an easy planet to observe, and we can learn a lot about these objects from the planet. 

 

The project is also researching the radii of M-type dwarf stars, and small stars with slow rotation periods. 

 

HAT is the Hungarian Automated Telescope network of optical refractor telescopes. Altogether there are 6 robotically operated telescopes of diameter 11cm that detect and characterise extrasolar planets using the same method as MEarth; by looking at variabiltity in brightness of a star caused by a transiting planet. 

 

This project has so-far discovered 29 exoplanets using this transit method. Also, the telescopes discovered an additional companion to the star HAT-P-13, which could either be a massive planet or a small brown dwarf. This stands as the first known transiting planet in a system with an outer companion an a well-characterised orbit. 

 

A downloadable version of the visitor guide for these projects will be made available soon!