It seems that in outer space, as it is on Earth, humanity is simply leaving far too much of its trash behind. According to a report released in April by the European Space Agency, the organisation is tracking about 54,000 pieces of orbital debris larger than 10cm. There are an additional 1.2 million fragments measuring between one and 10cm. These bits and pieces may not sound like much at first - the cosmos is a big place - but as far back as the late 1970s, scientists were already worried.