/sci/ - Science & Math

The habitable zone is probably wider than that yeah, but keep in mind things like tardigrunts mainly just go into stasis when in an extreme environment, and will inevitably die if they don't make their way back to sensible conditions soon enough.

They are talking about the type of life as we know it. There's probably life all over the universe but we just can't recognize it as it's so different than us

>>11660910
Goldilocks zone is planets that can have liquid water somewhere on them. Extremophiles that can live in acid lakes or next to hydrothermal vents aren't an exception to that rule.

Tardigrades can survive in the vacuum of space by forcing all the water out of their bodies but they're completely dormant in this state. They can't reproduce until they get some liquid water in them.

>>11660910
"Extreme" to us, but the conditions the live in are still mild in comparison to most other unhabitable plants for Earth like libing beings.
Most extremophiles live either near 0°C (freezing water point) or near 100°C (boiling water point). So liquid water is a must for Earth like living beings. If you grab any biochemistry book, you'll see that water and it's properties are a really important part of what makes life as we know it.

Could be wrong but pretty sure the Goldilocks zone thing only considers life that requires liquid water

There's no reason to think that all life in the universe is entirely dependent on water, there could be life that uses something else like ammonia as a solvent, and would therefore tolerate a different temperature range

Would be nice to have a sample size of greater than 1 for planets with life and different types of biochemistry; perhaps one day scientists will instead point to like 3 or 5 different rings around a star and say "here's the zone for water, here's the zone for ammonia, here's the zone for hydrogen fluoride, here's the zone for methane..."