b'Carnegie Science|Fall 2020 19The research team was led by Carnegies postdoctoral fellow Fabo Feng (left) and staff astronomer Paul Butler (right), with a host of other Carnegie researchers. Their ultimate goal is to be able to determine if planets orbiting nearby stars host life. Images courtesy Carnegie Institution for ScienceMany planets that orbit red dwarfs in the habitable zone arethe nearest stars to our own Solar System, especially those that are tidally locked, meaning that the period at which they spin aroundpotentially habitable, added Carnegie coauthor Jeff Crane.their axes is the same as the period at which they orbit their hostThis research effortwhich also included Carnegies Steve star. This is similar to how our Moon is tidally locked to Earth,Shectman, John Chambers, Sharon Wang, Johanna Teske, Matas such that we only see one side of it. As a result, these exoplanetsDaz, and Ian Thompson; as well as Steve Vogt of the University of have a very cold permanent night on one side and a very hotCalifornia, Santa Cruz; Hugh Jones of the University of permanent day on the othernot good for habitability, explainedHertfordshire; and Jennifer Burt of NASAs Jet Propulsion Feng. GJ180d is the nearest temperate super-Earth that is notLaboratoryculled and reanalyzed data from the European tidally locked to its star, which probably boosts its likelihood ofSouthern Observatorys (ESOs) Ultraviolet and Visual Echelle being able to host and sustain life. Spectrograph (UVES) survey of 33 nearby red dwarf stars, which The other potentially habitable planet, GJ229Ac, is the nearestoperated from 2000-2007 and was released in 2009. temperate super-Earth to us, located in a system in which the hostWe have been led to this result by antique data, joked Butler. star has a brown dwarf companion. Sometimes called failed stars,Once targets were discovered in the UVES archives, the brown dwarfs are not able to sustain hydrogen fusion. The brownresearchers used observations from three planet-hunting dwarf in this system, GJ229B, was one of the first brown dwarfs toinstruments to increase data precision: the Carnegie Planet Finder be imaged. It is not known if brown dwarfs can host exoplanets onSpectrograph (PFS) at Carnegies Las Campanas Observatory in their own, but this planetary system is a perfect case study for howChile; ESOs High Accuracy Radial velocity Planet Searcher exoplanets form and evolve in a star-brown dwarf binary system.(HARPS) at La Silla Observatory; and the High Resolution Echelle Our discovery adds to the list of planets that can potentiallySpectrometer (HIRES) at the Keck Observatory.be directly imaged by the next generation of telescopes, Feng said.Combining the data from multiple telescopes increases the Ultimately, we are working toward the goal of being able tonumber of observations and the time baseline, and minimizes determine if planets orbiting nearby stars host life.instrumental biases, Butler We eventually want to build a map of all of the planets orbitingexplained.SUPPORT:This artists concept shows GJ180d, which is the nearest temperate super-Earth to us thatA NASA Hubble Fellowship provided is not tidally locked to its star. This makes it more likely to be able to host and sustain life.support, in part, for this work. Image courtesy Robin Dienel, Carnegie Institution for Science'