The second Alien The Janitor defends Earth from
The Solarmen we're forged in the same place Thor had Storm breaker made using the solar power of a thousand dead Stars to make something to fight against the dark elves in that war. But they became self aware and tried to convert lots of people into Solarmen. The man before Odin banished them to their own realm (planet) Zondasck. The Time Lord's knew about these things and have fought them before and won.