Researchers have found a new method to search for habitable planets. They have discovered a technique that uses the planet’s atmosphere to get information about its mass. This novel approach could speed up the pace at which scientists can sort through planets that have the potential to host life.
The new technique is particularly significant for planets orbiting stars known as red dwarfs because other, current methods of trying to gauge their mass do not function very well.
While it is important for a planet to orbit within a star’s habitable zone in order to support life, it is not the only factor. Knowing a planet’s mass is also crucial because it allows scientists to estimate the bulk density of the planet – rocky, gaseous, predominantly water in some form or a mix.
Current methods of estimating mass only allow researchers to gain the minimum or maximum mass of a planet. The new approach could improve the accuracy of these measurements.
This method was discovered by Julien de Wit, a graduate student at Massachusetts Institute of Technology (MIT). He was working on a model for a planet based on its transmission spectrum – a common technique today – when he realized that there may be a way to use the same equations to calculate mass. He showed his calculations to Sara Seager, a planetary scientist at MIT, and she recognized their importance.
The calculations work because one of the features affecting the changes in an atmosphere’s pressure with altitude is gravity. Thus, gravity can be defined in terms of a planet’s radius and mass, allowing for the determination of mass.
This new method may lead to greater insight and speed in the search for habitable planets.