<a href="https://en.wikipedia.org/wiki/Soviet_Union" id="mw2A" rel="mw:WikiLink" title="Soviet Union">Soviet</a> satellite <a href="https://en.wikipedia.org/wiki/Kosmos_954" id="mw2Q" rel="mw:WikiLink" title="Kosmos 954">Kosmos 954</a>, with a nuclear reactor on board, burns up in Earth's atmosphere, scattering radioactive debris over Canada's <a href="https://en.wikipedia.org/wiki/Northwest_Territories" id="mw2g" rel="mw:WikiLink" title="Northwest Territories">Northwest Territories</a>. Only 1% is recovered.