A new planet hunter has been fired up in Northern Chile — the ESPRESSO machine doesn’t make coffee but is a massive spectrograph that is the most powerful planet-hunting tool ever to scan the cosmos.
What does ESPRESSO stand for?
It stands for the Echelle SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations. It is a light detector that determines what wavelengths or colours are coming from the distant reaches of the galaxy. It’s a device that is connected to European Southern Observatory’s Very Large Telescope in Chile that doesn’t have a lens exactly like a traditional telescope but instead detects electromagnetic frequencies, which includes light waves.
What is ESPRESSO looking for?
It is scanning the skies for habitable planets. We have heard a lot in the news about various planet hunting missions, Kepler for instance, and the James Webb Space Telescope to be launched in spring 2019.
But this ESPRESSO spectrograph is bound to an Earth-based telescope. It’s a little harder to see beyond the atmosphere of Earth, but it’s also a lot easier to fix when things go wrong.
So far, dozens of rocky Earth-like planets have been found. The first step in finding planets like Earth is to just find other planets orbiting around other stars — there are literally an infinite amount of them. Then, those planets have to be narrowed down to those that are rocky, those that are also the right distance away from the star they orbit to not be too hot nor too cold, something called the Goldilocks zone.
This Goldilocks zone is essential because it’s when it is just right that liquid water could form on a rocky planet. And voilà … a second Earth. If only it were that easy.
How do you hunt for planets far off in space?
There are a few different strategies to do this. ESPRESSO uses something…