1947 June 27 — Pentagon Army AF Public Relations Officer Capt. Tom Brown says the army has no idea what the discs are.http://sohp.us/collections/ufos-a-history/pdf/GROSS-1947-Revision.pdf 

1947 June 27 — In a United Press dispatch from Pendleton, Oregon, Kenneth Arnold expresses frustration over the furore that his saucer sighting has caused. A preacher has called him from Texas to say that the flying discs are “harbinger of doomsday.” A woman recognizes Arnold in a Pendleton café and runs out shrieking that he is “the man who saw the men from Mars.” He says the whole thing has gotten out of hand: “Half the people I see look at me as a combination Einstein, Flash Gordon, and screwball. I wonder what my wife back in Idaho thinks.” 

1947 June 27 — Capt. Robert D. Dwan, a pilot out of Alamogordo Army Air Field [now Holloman AFB], New Mexico, is flying a private plane near Engle, New Mexico, at 3,000 feet, when he looks down and sees a “ball of fire, with a fiery blue tail behind it.” The object is about 2,000 feet below him, and he is “certain it is a meteorite.” The object disintegrates as he watches it. 

1947 June 27 — 9:50 a.m. Mrs. W. B. Cummings is driving about 5 miles southeast of San Antonio, New Mexico, when she sees a bright silver object descending quickly in the east. It leaves a short white trail. White Sands officials say there has been no missile testing since June 12.

1952 June 27–30 — Ruppelt visits McChord AFB to look into recent sightings there. Capt. Harnnagy of the 4704 Air Defense Wing Intelligence tells him that the objects are always seen in the northern sky around 8:00 p.m.

1970 June 27 — 11:40 a.m. Aristeu Machado, his wife and children, and João Aguiar of the Brazilian Federal police, see a metallic, domed disc resting on the surface of the Atlantic Ocean about a half-mile off the coast of Rio de Janeiro, Brazil. Two humanoid figures are standing on the rim. After a while the object skims the surface of the water and takes off, lights flashing from the underside. Once airborne, the wife can clearly see the two occupants sitting inside.

1982 June 27 — Following a screening of E.T.: The Extraterrestrial at the White House, President Reagan leans over to director Steven Spielberg and comments, “You know, there aren’t six people in this room who know how true this really is.”

2013 June 27 — 12:20 p.m. An F/A-18F Super Hornet from Strike Fighter Squadron 11 (VFA-11, the “Red Rippers”), flying out of Naval Air Station Oceana in Virginia Beach, Virginia, has an encounter with an “aircraft [that] was white in color and approximately the size and shape of a drone or missile” in the W-72 warning area, a patch of airspace off the coast of Virginia and North Carolina. The jet’s crew visually acquires it as they see it “pass down the right side of their aircraft with approximately 200 feet of lateral separation” while flying at an altitude of 17,000 feet. It is climbing and has a visible exhaust trail. Neither the Super Hornet nor NAS Oceana records a radar track of the object. The Navy tells units to be aware of the potential hazards posed by unauthorized or uncoordinated drone operations. https://www.thedrive.com/the-war-zone/33371/here-are-the-detailed-ufo-incident-reports-from-navy-pilots-flying-off-the-east-coast

2019 June 27 — The Storm Area 51 Facebook event is created by college student Matty Roberts as a joke, unaware of the viral attention it will receive. He comes up with the idea of suggesting a raid on the facility to search for aliens after watching Area 51 conspiracy theorist Bob Lazar and filmmaker Jeremy Corbell on The Joe Rogan Experience podcast on June 20. The event plans for the raid in Amargosa Valley on September 20. More than 2 million people responded “going” and 1.5 million “interested” on the event page, which subsequently attracts widespread media reaction and makes the event become an internet meme.