- "Tachyon device tracked you on Earth Thirty-Eight when you met her, so you should find her there."
- —Cisco Ramon[src]
This Earth is one where the existence of alien life has been common knowledge for over a decade - in particular, the Kryptonian heroes Superman and Supergirl. Barry Allen accidentally traveled to this Earth while testing out his Tachyon device and was able to return home with Supergirl's aid.
When Cisco and Gypsy had a duel over the life of H.R. Wells, they crossed the dimensions and landed on this Earth, in the office of James Olsen. They were seen by Eve Teschmacher fighting before vanishing into another breach.
Recently the atmosphere of Earth Thirty-Eight has been seeded with a trace amount of lead making the planet uninhabitable to Daxamites.
From Earth One
From Earth Nineteen
- United States of America
- "Welcome to Earth-2" (vision)
DC's Legends of Tomorrow
- "Invasion!" (mentioned)
Adventures of Supergirl
- The number 38 is a reference to 1938, the year Superman debuted.
- Barry Allen went through a series of names from individuals on his Earth and Earth Two, seeing if they exist on Earth Thirty-Eight. After running them by Kara Danvers and looking them up online, it appears that Harrison Wells, Cisco Ramon, Caitlin Snow, Green Arrow, Black Canary, The Atom, Firestorm, Zoom and even himself, as The Flash, all either do not exist or at the very least don't share the same names and identities of their doppelgängers.
- While Central City still exists on Earth Thirty-Eight, S.T.A.R. Labs does not.
- The existence of extraterrestrial life is common knowledge on Earth Thirty-Eight whereas only a small number of individuals outside of the government know of them on Earth One, at least in the 21st century.
- It is identical to Earth One in many ways such as aesthetic, currency, existence of real life figures, popular culture and technology, unlike Earths Two and Three.
|Earth One • Earth Two • Earth Three • Earth Sixteen • Earth Seventeen • Earth Nineteen • Earth Thirty-Seven • Earth Thirty-Eight|