You might wonder what
that means, scientifically...
Temperatures like the -36º degrees Fahrenheit faced by my friends in Fargo, North Dakota this week approach a level of frigid that can alter the very nature of the matter around us.
First, the basics:
The most obvious affect
of lower temperatures on molecules is that they can cause substances
to go through phase transitions, meaning changing their
characteristic nature from gas to liquid or
liquid to solid.
...air molecules begin to move slower, exerting less pressure on surfaces and causing car tire pressures to decrease.
Water freezes and the air can't hold as much water vapor.
That's how that boiling water trick works - water droplets vaporize from the heat, but the air's too cold to hold any more water vapor, so the droplets quickly freeze out.
The U.S. Armed Forces required certain liquid propellants to function down to -65º Fahrenheit for certain missiles, Jon Austad from the Hylleras Center for Quantum Molecular Sciences and Kathrin Hopmann from the Arctic University of Norway explained to Gizmodo via email:
Then there's an even weirder phenomenon, called,
Below 56º Fahrenheit (13º Celsius), tin transforms from a metal into a brittle, non-metallic form.
It's a slow process at higher temperatures but occurs much quicker around -22º Fahrenheit (-30º Celsius).
The tin containers filled
with kerosene that Scott's team had stashed away
turned out to be empty - possibly
because tin pest created leaks in the cans.
typically lead to more higher-energy collisions between
faster-moving molecules, and thus would lead to faster chemical
reactions. So lower temperatures would, therefore, slow down
But of more worry is the electrolyte that the molecules travel through, which solidifies at these low temperatures.
Xiao Ji's team is
working on better electrolytes to combat that problem.
In many of the labs in
the Imperial College chemistry department, researchers are more
interested in the -109.2º Fahrenheit, (-78.5º Celsius) kind of cold,
the temperature at which carbon dioxide freezes. That's more of a
convenience thing, since at that temperature, reactions too quick to
study at room temperature become controllable in the lab.
In fact, there are... one holy grail of physics is the room-temperature superconductor. Some materials at low temperatures undergo another kind of phase transition such that electrons move without any electrical resistance.
If room-temperature superconductors were realized, they could drastically reduce energy costs or help other technologies, like quantum computers, become more feasible.
But there's a catch:
Ultimately, the most important chemical reactions to our livelihood, the ones occurring in our own bodies, are the ones that we should be most worried about.
Indeed, one researcher
wrote a paper on the
temperature limits of Earth's life.
Chemical reactions inside cells function at optimal temperatures,
and lower temperatures can cause disruption. We eat food in order to
power those reactions and keep our body warm, but without a coat, we
would quickly succumb to the effects of cold.
Vertebrates are relatively wimpy and have evolved things like fur and feathers (and the ability to construct heated buildings and sew clothing) in order to keep their cells operating at optimal warm temperatures.
Marine life can only handle the coldest temperature at which water exists as a liquid, 32º Fahrenheit for freshwater and 28º Fahrenheit for seawater. Older data suggests that flowering plants can survive down to -94º Fahrenheit (-70º Celsius), but can only thrive at around 32º Fahrenheit (0º Celsius).
At temperatures below -4º Fahrenheit (-20º Celsius), bacteria can still multiply, albeit more slowly, according to one study, perhaps thriving on saline meltwater puddles.
archaea, and even the microscopic
tardigrades, can survive
reanimation after freezing to temperatures below
-320º Fahrenheit (-196º Celsius),
though tardigrades still require at least 32º degree Fahrenheit
temperatures to thrive.
It's interesting to think
about these extremes of bodily chemistry to better understand
whether life could exist elsewhere - places where water might remain
a liquid at colder temperatures thanks to the presence of salts.