US or UK? Trident II D5 Missile Test Sparks Speculation

A nuclear missile test involving a UGM-133 Trident II D5 Submarine-Launched Ballistic Missile (SLBM) occurred in the North Atlantic on September 21, 2025. Reports from the Russian media outlet Russia Today indicate that a nuclear submarine, likely belonging to the United States or the United Kingdom, launched the missile from deep within the Atlantic Ocean. The exact details surrounding the test remain unclear, as neither the U.S. Navy nor the Royal Navy has issued an official statement regarding the event.

On September 17, a navigational warning was issued for the area where the missile test occurred, covering the period from September 17 to 22. The timing aligns with the reported missile launch, which took place at approximately 23:25 UTC. Social media platforms featured videos capturing what is believed to be the missile launch, with one post stating, “Footage tonight from all over Puerto Rico captured the launch of what is believed to be a UGM-133 Trident II.” While no official confirmation has been provided from U.S. or British authorities, the Caribbean Astronomy Society characterized the object seen in the sky as a “military test.”

This recent event stands out as the first Trident II D5 test firing since September 17, 2021, when the U.S. Navy conducted a scheduled test of unarmed missiles from the USS Wyoming, an Ohio-class ballistic missile submarine, off the coast of Cape Canaveral, Florida.

Understanding the Trident II D5 SLBM

The UGM-133 Trident II D5 SLBM is one of the most powerful nuclear missiles in existence. Deployed on the U.S. Navy’s Ohio-class and the UK’s Vanguard-class submarines, the Trident II D5 is designed to enhance strategic deterrence capabilities. The U.S. operates 18 Ohio-class submarines, of which 14 are armed with the Trident II D5. In contrast, all four Vanguard-class submarines in the UK’s fleet are equipped with this missile under the Polaris Sales Agreement.

Each Ohio-class submarine can carry up to 20 Trident II missiles, while each Vanguard-class submarine can house 16. With a range of 4,000 nautical miles (approximately 4,600 statute miles or 7,360 kilometers), the Trident II D5 can carry up to 12 warheads, including W76-Mk4/Mk4A or W88-Mk5 multiple independently targetable reentry vehicle (MIRV) warheads, allowing it to strike multiple targets in a single launch. Current treaties with Russia restrict the number of warheads per missile to four or five MIRVs.

Manufactured by Lockheed Martin, the Trident II D5 missile measures 44 feet (approximately 13.41 meters) in length, has a diameter of 83 inches (about 2.11 meters), and weighs 130,000 pounds (around 58,500 kilograms). Each missile costs approximately $30.9 million.

The implications of nuclear tests such as this one extend beyond technical specifications; they touch upon geopolitical tensions and the ongoing dialogue between nuclear powers. As the situation develops, further clarity from the involved nations may shed light on the motivations behind this missile launch and its implications for global security.