On 28 June 2019, SpaceX announced that it had lost contact with three of the 60 satellites making up the Starlink mega constellation. The dysfunctional satellites' orbits are expected to slowly decay until they disintegrate in the atmosphere.[85] However, the rate of failure for satellites in mega-constellations consisting of thousands of satellites has raised concerns that these constellations could litter the Earth's lower orbit, with serious detrimental consequences for future space flights.[86]