Corrected entry: It's stated that Omega caused the black hole when he created a supernova. Supernovas don't cause black holes, they're created by huge stars imploding.
Corrected entry: The Doctor followed The Daleks to Spiridon but then is shocked to see the Dalek at the end of episode one.
Correction: The Doctor is shocked by the Dalek as the Dalek is invisible, and the Doctor, to this point, is unaware that Daleks can be invisible.
Corrected entry: A calendar seen in the story is for February 1972. (It is a leap year...there are 29 days on the calendar, and February only has 29 days once every four years). However, an ambulance seen later in the same story has an "L" suffix on its licence plate. "L" suffixes were only issued for the period 1 August 1972 to 31 July 1973, so the calendar must be months out of date...
Correction: Maybe no-one remembered to turn the calendar to the new month?
Corrected entry: The entire "running out of oxygen" plotline in episode one creates numerous contradictions with previous episode. We have seen the TARDIS materialize on the moon, in space and in other environments without oxygen so it must have its own air system. In addition, the TARDIS has been established to be vast, making it highly unlikely one comatose time lord could use up the entire air supply.
Correction: The plant thing growing on the door is sucking the oxygen out of the TARDIS.
Corrected entry: When Jo is calling for help she keeps saying "Calling Greyhound One..." then when Benton answers he says "Station to Greyhound One."...so which one of them is "Greyhound One", Jo - or Benton?
Correction: Answer: neither of them. The callsign 'Greyhound One' is actually the callsign of Brigadier Lethbridge-Stewart, who uses it in at least two stories ('Invasion of the Dinosaurs' and Season 25's story 'Battlefield'). So why is Benton answering using the Brigardier's callsign? Hasn't he got one of his own? Perhaps that's another error althogether...
Correction: Basic lifecycle of extremely massive stars: they're born, they live for several million years, they die in a large supernova. There are two potential outcomes of a supernova: the creation of a pulsar or neutron star, or the creation of a black hole, depending on how massive the original star was. So yes, black holes are indeed created in supernovas.