The Finnish Meteorological Institute (FMI) has asked members of the public to report any sightings of a large, floating weather balloon which has gone missing over the Pallastunturi area of Finnish Lapland.
Filled with helium, the red balloon carries instruments that record information such as atmospheric pressure and temperature, and was being used in a FMI-led research project.
According to a statement, the balloon may have drifted over the Vätsäri Wilderness Area, which is located along the northeastern shore of Lake Inari — or over the lake itself — as it moves towards northern Norway and the town of Kirkenes.
However, the FMI believe the balloon remains on the Finnish side of the border as of Tuesday afternoon.
Weather balloons are usually tethered to the ground via strong wires, and it is rare for them to break loose.
"This is the first time I've encountered something like this," said Kimmo Neitola, a researcher with 15 years experience of studying the atmosphere.
Neitola, who is a Postdoctoral Researcher for the Institute for Atmospheric and Earth System Research at the University of Helsinki, informed Yle about the runaway balloon on behalf of his colleague David Brus.
Brus is leading the project which is using the balloon to record atmospheric pressure.
"The loss of the balloon will affect Brus' research campaign, as new equipment is unlikely to be available this winter," Neitola noted, adding that any observations of the balloon are important, especially its location and altitude.
The balloon was flying at about 600 metres when it became untethered, but it is possible that it could drop in altitude or even land on something.
In addition, thousands of euros worth of measuring equipment are also now missing, Neitola added.
The FMI has offered a reward of 500 euros for sightings that lead to the recovery of the measuring equipment. Any sightings or information can be sent to kimmo.neitola(at)helsinki.fi.
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