Superyacht with helipad moors up in Weymouth Bay

Who would live in a yacht like this? She's about 100 metres long, four decks high and is carrying the British flag. Plus a green helicopter is parked at the back!

It's a rare sight this side of Portland Port, which has berths deep enough to accommodate superyachts.

Who owns her? Are they on board? Are there any VIPs gearing up for New Year celebrations in Weymouth? Perhaps it's just the crew, who have decided to stop off in Weymouth over the festive period. The tender is out the back, ready to come into shore. 

If only the current would swing her the other way, so we can read the name of the yacht through our binoculars.

She's been sitting there for a few days. She's not registered on ship AIS, an automatic identification system for commercial vessels. 

Sources tell us she belongs to Microsoft co-founder Paul Allen, and she's up for sale. So is she the Tatoosh? 

Paul Allen formerly owned one of the world's biggest superyachts, Octopus, which came to visit Portland Port a few years ago.