The test photo includes more than 200,000 stars.
Helium is the second most common element in the universe, but more than a decade of searching for the gas in the atmospheres of exoplanets has proven unsuccessful, until now.
TESS stands for Transiting Exoplanet Survey Satellite, and its mission is to identify planets orbiting the brightest stars in our neighborhood of the universe.
TESS will scour the skies for signs of undiscovered worlds.
Scientists are excited about the prospect the mission holds for new discoveries, but if you're just learning about the mission now, here's what you need to know.
“It’s just completely bizarre that we should have two planets the same size but opposite ends of the habitability spectrum.”
The planet is likely the densest Earth-sized planet ever found.
"This is an enormous challenge," Hawking said in the film. "To leave Earth will take a global approach and everyone should join in."
The spacecraft has spotted almost three-quarters of the alien planets scientists have identified to date.
The dust could be evidence of evolving infant exoplanets.
The numbers contradict everything we know about how moons form.
An intriguing feature of its orbit ties this telescope's destiny to a lunar schedule.
The planets sit in a galaxy 3.8 billion light years away.
The new results explain how two planets in this distant solar system may be positioned just right to create life-friendly conditions.
The space agency has big goals for 2018.
An atmosphere is basically a giant blanket that can protect a planet from a star's barrage of dangerous radiation.
Scientists didn't find aliens in 2017, but here's what they did find.
Knowing what we haven't found can help scientists see what they could still be missing.
The lipstick-shaped satellite has already done incredible science, whatever news Thursday's announcement brings.