"Due to an abnormality of the spacecraft's on-board computer systems, the engine automatically shut down and the rocket safely splashed down to the ocean", IST said.
The takeoff occurred at 4:20 p.m. local time (07:00 GMT) from the Taiki spaceport in Hokkaido, the company said on its Twitter account. MOMO-F4’s launch and flight was streamed live on social media, Sputnik reported.
Interstellar Technologies earlier successfully launched the country's first private rocket, dubbed MOMO-3 in May. Two previous launches in July 2017 and in June 2018 failed.
MOMO-4 is a 10-metre long rocket with a diameter of 50 centimeters. It can carry surveillance devices weighing up to 20 kilograms. The launch was initially scheduled for 20 July, but had to be cancelled due to technical problems.
While MOMO cannot put satellites into orbit, the company plans to create a rocket capable of launching satellites and conduct the first launch by 2023.