The exoplanet was found by using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured.

Given the planetary radius and temperature, atmosphere is likely to contain an abundant carbon monoxide and dense tholin haze.

Observations made on the planet confirmed that it was a fully formed exoplanet, not just a protoplanet that was still in the stages of developing.

There are relatively few other exoplanets discovered to date with an age this young, all of which are non-transiting (with some that were detected around hot A-type and B-type stars, such as HD 95086 b and HIP 78530 b, however these could be brown dwarfs due to their mass).

The hot Jupiter exoplanet V830 Tauri b, published in the same issue of the journal Nature as the discovery of K2-33b, may be younger with an age of around 2 million years (around the time that humans evolved on Earth),[7] but the existence of this planet is disputed.

Given the young age of this exoplanet, several theories of planetary migration can be ruled out because they take too long to form close-in planets.

[2][1] Trevor David of Caltech in Pasadena stated on the discovery of the exoplanet "The question we are answering is: Did those planets take a long time to get into those hot orbits, or could they have been there from a very early stage?

From 23 August to 13 November 2014, the spacecraft collected data from the core of Upper Scorpius, which included K2-33.

The observations were made with the Immersion Grating Infrared Spectrometer (IGRINS) on the 2.7-m Harlan J. Smith Telescope at the McDonald Observatory.