What should have been a historic moment for the UK ended in failure last night after an undisclosed “anomaly” prevented the country’s satellite mission from reaching orbit. The Virgin Orbit “Start Me Up” mission was the first-ever rocket launched from British soil.

The first stage of the mission proved successful — Virgin Orbit’s Cosmic Girl (a converted Boeing 747 acting as a carrier aircraft) took off from Spaceport Cornwell on January 9th as planned and released the LauncherOne rocket over the Atlantic Ocean at 11:11 PM GMT (6:11 PM ET). According to the live Virgin Orbit mission updates on Twitter, the LauncherOne rocket experienced a successful stage separation and second-stage engine ignition.

Virgin One initially tweeted “LauncherOne has … successfully reached Earth orbit! Our mission isn’t over yet, but our congratulations to the people of the UK! This is already the first-ever orbital mission from British soil – an enormous achievement.” This tweet was later deleted and replaced with an update saying that an anomaly had prevented the rocket from reaching orbit.

The LauncherOne rocket was carrying a payload of nine satellites, the first to be manufactured in Wales. These satellites were not released and were lost alongside the LauncherOne rocket. Cosmic Girl and its crew safely returned to Spaceport Cornwall. “It’s just absolutely devastating, and we put our hearts and soul into this” said Melissa Thorpe, the head of Spaceport Cornwall in a statement to The Guardian. “The next time we go it will be even better.”

This is the first LauncherOne mission to fall short of delivering its payloads out of five launch attempts. Its first test flight in May 2020 also suffered an anomaly while carrying a weighted dummy payload as practice for actual customer satellites.

Matt Archer, Commercial Space Director at the UK Space Agency, said in an official statement that the agency will be working with Virgin One to investigate what caused the anomaly in the coming days and weeks. “We will work tirelessly to understand the nature of the failure, make corrective actions, and return to orbit as soon as we have completed a full investigation and mission assurance process.”