North Korea conducted what has been referred to by experts as their “most successful” missile test to date on Sunday, demonstrating their ability to strike U.S. bases as far away as Guam with a hypothetically nuclear tipped missile.

Kim Jong Un is said to have personally supervised the launch of the Hwasong-12 missile, a never before tested iteration of North Korea’s ballistic missile program, and feasibly a significant stepping stone toward the development of a true Intercontinental Ballistic Missile capable of striking the mainland United States.

According to state-owned news outlet KCNA, Sunday’s test was “aimed at verifying the tactical and technological specifications of the newly developed ballistic rocket capable of carrying a large-size heavy nuclear warhead.”

KCNA went on to report that the Hwasong-12 reached a maximum altitude of 2,111.5 kilometers (or 1,312 miles) above the surface of the earth before re-entering the atmosphere and impacting a predesignated target 787 kilometers (489 miles) away.

“North Korea’s latest successful missile test represents a level of performance never before seen from a North Korean missile,” aerospace engineer John Schilling wrote for 38 North, published by the US Korea Institute at Johns Hopkins University.

David Wright, the co-director and a senior scientist at the Union of Concerned Scientists, specializes in ballistic missile proliferation, ballistic missile defense, and nuclear weapons policy.  According to a statement he published on his site, if the information provided by the North Korean media is accurate (or even close), it may be indicative of a ballistic missile capable of reaching targets as far away as 4,500 kilometers, or 2,796 miles.  According to his analysis, it isn’t the distance the missile covered that gives away its potential, but rather how long it took to arrive on target.  According to Wright:

“A missile with a range of 1,000 km (620 miles), such as the extended-range Scud, or Scud-ER, would only have a flight time of about 12 minutes if flown on a slightly lofted trajectory that traveled 700 km.

A 30-minute flight time would instead require a missile that was highly lofted, reaching an apogee of about 2,000 km (1,240 miles) while splashing down at a range of 700 km. If that same missile was flown on a standard trajectory, it would have a maximum range of about 4,500 km (2,800 miles).”