The first Finnish satellite ever launched, dubbed the Aalto-2, burned up late Wednesday or early Thursday Finnish time. The small device burned up as it entered Earth's atmosphere, becoming an artificial meteor.
Weighing just two kilos, Aalto-2 was launched into space in April 2017. It was set into orbit from the International Space Station in the following month, but contact with the satellite was lost soon after that.
Mission: Northern Lights layer
The satellite was intended to join other small satellites in measuring the thermosphere, a layer in the Earth's atmosphere where the aurora borealis (Northern Lights) appear.
The leader of the satellite project at Aalto University, Assistant Professor Jaan Praks, tells Yle that it was possible to track the satellite's destruction with reasonable certainty based on orbit predictions by the North American Aerospace Defense Command (Norad).
"The last prediction was given with 15-minute precision, and it was around midnight. That was the only confirmation that we have at the moment," Praks said on Thursday.
"It is possible that those organisations tracking space junk may at some point be able to provide more precise information about objects that have entered the atmosphere. Since this was a very small object that was completely destroyed on entry, there is no more accurate tracking," he explained.
Norad continuously tracks all known space objects and their orbits using lasers and radars.
Two other Finnish satellites still in orbit
A companion device, the Aalto-1, which began its space voyage slightly later, has operated as planned. It has made many observations, including of a radiation storm emitted by the Sun in 2017. The Aalto-1 remains in orbit at altitude of about 515 kilometres.
Another satellite designed at Aalto University, the Suomi 100, was launched from California in early December 2018 after a long series of delays. It was originally to be launched to mark Finland's centennial in 2017.