Nasa is slated to hold a press conference on Wednesday to present a "discovery beyond our solar system," leading many to speculate that the agency might have found exoplanets capable of sustaining life.
The agency said it will make a major announcement on new findings on planets, but offered no other details.
"NASA will hold a news conference at 1 pm EST (6pm GMT) Wednesday, February 22, to present new findings on planets that orbit stars other than our sun, known as exoplanets," said the space agency.
The announcement has set astronomy community and social media abuzz. The best guess so far is that the agency might have found a planet capable of supporting life.
Since Nasa has mentioned it is related to exoplanets, we at least know that the discovery is beyond our solar system. Nasa has been studying dozens of planets that orbit Sun-like stars.
At a press conference earlier this year, it announced the discovery of 1,284 new planets, nine of which were in the "habitable zone" around their host star.
The first Earth-like planet to be discovered was Kepler-186f, a rocky planet that lies within the habitable zone and is similar in size to Earth.
Where to watch live
If you want to know all about the big discovery as and when it is happening, log on to this site at 6 pm GMT on February 22.
The announcement will air live on NASA Television and the agency's website and those on Twitter can ask questions to the panel using the #askNASA. Post the announcement the panel will also be hosting a Reddit AMA to take further questions on the discovery.