Roblox's public Events data for Universe 10563114921 was checked on . This is a scheduled event preview. The listed dates do not confirm that gameplay is already available.
Official event window
Roblox lists “🛸NEW ALIEN BIOME” from November 7 at 16:00 UTC through November 14 at 19:00 UTC. The event is hosted by the Roblox group “and Collect Rare Pets” for the Steal An Egg experience.
That start is November 8 at midnight in Singapore, Beijing and Manila. Check the official event card for your local time before joining.
What the teaser says
The official description says Paranoid Pete's radar is detecting stronger signs of extraterrestrial activity, UFO sightings are becoming more frequent, and a new Alien biome arrives next week. It does not give an entry route, Speed requirement, eggs, pets, income values or rewards.
A separate Update 10.5 announcement from the Roblox creator group says Pete arrives Monday, November 2, ahead of the November 7 biome release. It does not specify an hour or playable task. The event title and description remain a preview, not evidence that the biome can be entered yet.