The accounts that have been proven to support the crash of a UFO in Roswell, New Mexico are as follows:

1) We know something crashed in 1947 on a ranch in the vicinity of Roswell, New Mexico.
2) We know that some residents of the area stated they handled a material that consisted of an unknown metal.
3) We know that many of the residents reported seeing the craft and the bodies. There were people stationed at Walker air force base at that time who have come forward and divulged that they too seen the disc and the bodies.
4) We know that the remains of the weather balloon was transported to what is now Wright Patterson air force base, a military post that has been rumored to deal with other sensitive alien cases.
5) It is claimed by some that the actual UFO that crashed in Roswell never left the area. Instead, it moved to area 51. Area 51 refers to a location where alien studies are being conducted, and yet the existence of such a place is denied by the United States government. We know that area 51 does exist.
6) We know that a picture that depicts a letter has surfaced that was taken in 1947 during the aftermath of the crash. Using computers to enlarge the photographed letter, it was realized that the letter was an order to the major at Walker air force base to remain silent regarding the facts of the crash.
7) We know that the weather balloon story was a smoke-screen.
8) We know that the test-dummy explanation was impossible. Test-dummies were not used until six years later.

There has also been much debate about another UFO crashing in the Antarctic region

The wreckage was reported to have been brought back to the United States on the naval ship, USS Pine Island. According to reports, the USS Pine Island was involved in a military exercise, code-named operation Highjump in 1947.

According to our government, Operation Highjump entailed the following instructions:

(a) to train personnel and test material in the frigid zones;
(b) to consolidate and extend American sovereignty over the largest practical area of the Antarctic continent;
(c) to determine the feasibility of establishing and maintaining bases in the Antarctic and to investigate possible base sites;
(d) to develop techniques for establishing and maintaining air bases on the ice,
(e) to amplify existing knowledge of hydrographic, geographic, geological, meteorological and electro-magnetic conditions in the area.

Little other information was released to the media about the mission.

Most journalists were suspicious of its true purpose given the huge amount of military resources involved. The US navy also strongly emphasized that Operation Highjump was going to be a navy show; but, there were to be no spectators. It had been rumoured that Adolf Hitler had been building a secondary Nazi stronghold in the Antarctic region in the event that the war was lost. There are those who believe that Operation Highjump was actually an investigation into these claims. Then there are those who believe that Operation Highjump was a mission to search the Antarctic continent for signs of alien life-forms. The Antarctica has always been suspected of having an alien base on it. Over the years, there have been many UFO's sighted in the Antarctica. The continent itself is a vast area and most of it is inaccessible.

Whatever its outcome was to be, operation Highjump was not a small endeavour. It was comprised of some 4700 military personnel, six helicopters, six martin PBM flying boats, two seaplane tenders, fifteen other aircraft, thirteen US navy support ships and one aircraft carrier. Admiral Richard Byrd was the operation's leader, while Rear Admiral Richard Cruzan headed the task force. Supposedly, the USS Pine Island brought back a UFO from the Antarctic and took to San Diego. It then was transported to what is now Wright Patterson air force base.

We have been told in countless statements that mechanical problems occur in powered devices when they are in the close proximity of alien crafts. Let's look at the history of the USS Pine Island. It was built in 1942. It was launched on February 26, 1944. It departed from California on June 16, 1945. After numerous engagements in the West Pacific, it was called to duty during Operation Highjump in 1947. In August of 1947, it was sent to the Far East. It was decommissioned in May of 1950. After repairs had been made, it was re-commissioned on October 7, 1950. On June 16, 1967, the USS Pine Island was decommissioned for the final time. It was 25 years old. That is a very short life span for a ship. Thus, we can only wonder if the transporting of an UFO led to its early retirement.