Brontosaurus never actually existed. It was the product of mistakes made during the initial rush to discover as many dinosaurs as possible and putting skeletons together incorrectly.
Friday, 28 November 2014
Tuesday, 25 November 2014
Absolute Zero: The never-ending quest to get atoms to sit still
Last month
at a laboratory in Italy a group of scientists cooled a cubic meter of copper
to a temperature of 6 milliKelvins (-273.144 C, -459.66 F). According
to the researchers involved, for 15 days that 400 kg (880 lbs) of copper was
the coolest object in the universe. Of course, they had to say something that
sounded impressive because they had invested millions of dollars in grant money
to create arguably the most useless thing on the planet. The feat was
significant because it was the first time an object so large had been brought
close to the temperature of absolute zero (0 Kelvin, -273.15 C).
Temperature
itself is a surprisingly tough concept to pin down. Thanks to an influential
nation with a reputation for being stubborn when it comes to measurement, we
are forced to work with three different temperature scales: Celcius, Kelvin,
and Fahrenheit. Two of these scales are useful and one is arbitrary to the
point of being infuriating.
Celcius is
a useful scale that is grounded in practicality and common sense, but it is not
without its arbitrary aspects. It’s inventor, a Swede named Anders Celcius,
based the scale on water and set 0 as the point at which water freezes and 100
as the point at which is boils. That means at any point on the scale 1 degree
equals 1% of the change needed to bring water from freezing to
boiling. The Fahrenheit scale, invented by German Daniel Gilbert Fahrenheit, by contrast and for complicated
reasons, sets the freezing point of water at 32 degrees, the boiling point at
212 degrees, and historically also tried to incorporate human average body
temperature for no apparent reason. The result is a mess of a scale that is
really only used in the US, but for some reason we all acknowledge it and record F
temperatures in parentheses next to their Celcius values.
The Kelvin
temperature scale is the scale of science. While everyday scales based on the
behaviour of water make good sense for most of us, scientists like to have more
inarguable reasons for setting values. The Kelvin scale is based on the core
principle of temperature: the movement of molecules. At its root, that is all
temperature is. The faster the molecules in a substance are moving, the hotter
it feels and the higher we say its temperature is. For that reason, 0 on the
Kelvin scale is the point at which molecules stop moving completely, the
infamous “absolute zero.” Beyond that, 1 degree K is equal to 1 degree C. Nice and simple and sciencey.
So what is
with all the hubbub about scientists trying to cool things to absolute zero?
Well, as it turns out, reaching absolute is a tough thing to do... actually
it’s impossible. The problem is that for each degree you move down on any
temperature scale, the work you need to do to move down another degree
increases. Logically and mathematically it plays out that by the time you get
to 1 degree K, the amount of work you need to do to go down one more degree and
reach zero is infinite. That is why the Italian scientists were so excited to
reach 6 milliKelvins. Unfortunately for them this isn’t the coldest temperature
ever achieved in a lab. In 2003 scientists as MIT used heat shields and a process called laser cooling to chill a cloud of sodium atoms to
450 picoKelvins, that is 450 trillionths of a degree.
That is all
very cool (puns!), but what is the point of cooling something down to such a
degree (okay, stop)? Well it turns out that very very very cold things behave
differently than we would expect them to. Atoms that are cooled to within a
billionth of a degree of absolute zero can exchange electrons and from chemical
bonds at distances 100 times greater than they can at room temperature.
Also, at such low temperatures, atoms don’t exchange energy the way they do
when things are warmer. Instead of zipping around and bouncing off one another,
waves of energy called quantum mechanical waves overlap with each other, allowing groups of atoms to behave identically in a spooky choreographed dance as a kind of super-atom. Substances where this happens are called
Bose-Einstein condensates. The first Bose-Einstein condensate was created in
1995 in Colorado when researchers cooled a rubidium cloud to 170 nanoKelvins.
So I guess
there actually was a point to the Italian experiment. If there is one thing
research into temperatures as taught us it is to expect the unexpected. So even
though the cubic meter of copper didn’t form a united zombie-esque super-atom,
maybe it was worth doing. At the very least, we can claim to have created the
coldest piece of copper in the universe. Take that, aliens.
Friday, 21 November 2014
Sketchy Fact #68: Comet Conspiracy
According to scientists, comets smell like rotten eggs, horse urine, alcohol, bitter almonds, and vinegar. One suspects that the scientists have discovered something awesome that they don't want the rest of us to know about...
Tuesday, 18 November 2014
Comet Cruising: Why the Rosetta Mission is the Most Impressive Thing Ever
Well
humanity, it’s time to break out the bubbly. Every once in a while the
ingenuity of the world’s smartest people accomplishes something truly
remarkable. Whether it is sending the first satellite into space, mapping the
human genome, slicing bread, or putting a man on the moon; sometimes we earn the right to pat
ourselves on the back. On November 12, 2014 the European Space Agency (ESA)
gave us our most recent reason to feel smug as a species by dropping a lander
onto the surface of a comet. A first in human history.
The mission
is called Rosetta, the lander is named Philae in reference to the famous
Rosetta Stone which allowed people to decode ancient
Egyptian hieroglyphics. Philae is the name of the island where carvings were
found and compared to the Rosetta Stone to help break the code. The lander
settled down on comet 67P/Churyumov-Gerasimenko after first reaching its orbit
in August 2014. The goal of the mission is to collect and analyze samples from
the comet's surface to learn more about the early days of the solar system and
the origins of the Earth itself.
If you’re
wondering why it took so long for us to reach the surface of a comet, you are
seriously underestimating the difficulty involved. Rosetta isn’t a new thing.
It was launched in 2004 and has spent the past decade as a $1.75 billion
pinball in the inner solar system, circling the sun 4 times and using the
gravity of entire planets as paddles to finally make it to comet 67P. The cool
thing about space is that you can use the gravity of large objects to slingshot
you further and further away from your starting point. Rosetta has done this 3
times with the earth itself and once with Mars. If you’re interested in a video
mapping the whole 12 year journey of the spacecraft check out the ESA’s very cool video here.
After it's long ride, Rosetta finally met up with comet 67P in May 2014 and after 3 months of
getting closer and closer, settled into orbit in August. Since then it has been
mapping the surface of the 2.5 mile (4 km) wide comet looking for a good spot
to drop Philae. When the day finally came on November 12 everyone involved
crossed their fingers that their landing systems would go off without a hitch
so they could claim the historic achievement.
Unfortunately
in the world of space exploration things practically never go off without a
hitch. The plan was for Philae to fire 2 harpoons into the comet’s surface to
help hold it in place as it landed. The problem is that when the thing you are
controlling is 300 million miles away from the place you are controlling it,
sometimes things don’t work properly. The harpoons, which relied on nitroglycerin (which apparently doesn't work that well in a vacuum), didn’t fire and Philae was left
hurtling towards the surface without it’s safety net.
In the end,
the lander bounced twice before coming to rest. Bouncing is not a word you want
to hear with regards to your $1.75 billion spacecraft at the best of times, but
when you’re landing on a comet it is enough to get you panicking. The first
“bounce” lifted the lander 0.6 miles (1 km) of the comet’s surface and lasted 2
hours. The thing about comets is that compared to planets they are tiny and
have next to no gravity. The speed needed to escape the surface of 67P and fly into space is about
1 mile per hour (1.6 km/h) compared to 25,000 mph (40,230 km/h) to escape the
Earth. Philae’s first bounce was at about 85% the speed it needed to be hurled
into deep space. The second bounce
lasted only 7 minutes and wasn’t nearly as chancey. In the end, a group of
European scientists did get to celebrate... presumably after changing their underwear.
And with
that begins the real sciencey stuff. The lander will spend the next few days
collecting and analyzing major samples until it’s batteries run out. After
that will hopefully be able to use its solar panels and auxiliary batteries to
keep working until March 2015. The Rosetta orbiter will keep sending us data
until hopefully the end of next year. Regardless of what we learn from here on
out we know one thing for sure: when human’s set our best minds to achieving
things, there is very little we can’t do with a little luck… and a couple
crappy harpoons.
Friday, 14 November 2014
Wednesday, 12 November 2014
New Orleans is Sinking... No, Seriously
A couple
weeks ago we took an internet-fueled trip to China to learn about the Gobi Desert, which is threatening to consume Beijing. The Chinese government and its
people are hard at work trying to erase the environmental degeneration that has
led to their battle with the so-called “yellow dragon” but they aren’t the only
people who are at risk of losing their homes to a pissed-off planet. You may
not realize it, but the people of the state of Louisiana are up against their
own dragon, only it is bluer, wetter, and a whole lot bigger.
Since 1932
the slow but steady lapping of water from Gulf of Mexico against Louisiana’s
shores has caused around 1,900 square miles (almost 5,000 km2) of
land to fall beneath the waves. If the current trend of erosion continues,
geologists expect that the total loss of land could grow by another 1,750
square miles (4,500 km2) in the next 50 years. That number is kind
of ridiculous. The projected land that could be lost by mid-century is bigger
in size than the state of Delaware combined with the greater
Washington, DC/Baltimore area, just gone.
Ironically
enough, what is causing Louisiana to drown is pretty much the same thing that
is drying out China. As the population of the state has
grown and industrial interests have mowed over environmental concerns, trees
have been cleared and wetlands have been paved over or cleared out to make room
for people. When that happens, the root systems of plants wither away and with
them goes the stabilizing effect they have on soils. When the ground is only
loosely held together, it doesn’t take much in the way of waves to break it
apart completely.
Unfortunately
for Louisiana, their waves have also gotten stronger. If we completely set aside
the idea that climate change could be making storms stronger by warming ocean
temperatures, and if we decide to forget recent whoppers like Hurricanes
Katrina and Sandy, we are still left with a state that has lost its buffer
against the waves. When Europeans first showed up in Louisiana and set to work
perfecting the way people cook seafood, they caught their shrimp and
craw-daddies in a huge network of swamps and wetlands. What they probably
didn’t realize as they cleared those wetlands was that they were basically taking
the shocks off their car. See, when a really big storm nears land it kicks up a
lot of water and generates what is called a storm surge. A storm surge is a
massive wave that hits shore ahead of a hurricane. What swamps and wetlands do
is absorb most of the blow and contain some of the energy, protecting the
spaces further inland.
All-told,
Louisiana is in a little over its head with all this. Fortunately
for southern environmentalists, there was a massive oil spill in the Gulf of
Mexico a few years ago… Okay, actually it was a terrible ecological disaster
that the region is still recovering from, but it came with a silver lining.
Court rulings in the wake of the Deep Horizon spill have forced BP to fork over
as much as $18 billion in penalties for negligence. 80 percent of those dollars
are designated for coastal restoration. With the total cost of restoration
plans falling somewhere between $50 and $100 billion there will still be a
chunk of change unaccounted for, but picking BP’s pockets is a great start.
If the 19th
and 20th centuries were characterized by people plowing over nature
in a mad dash to acquire as much personal comfort as possible, the 21st
century is shaping up to be one where we make amends. Between trees getting
planted in China, wetlands being restored in Louisiana, and a score of other
massive environmental efforts underway all over the world, humans are repairing
damaged environments on a scale never before conceived of. It’s going to take
more than flowers and a box of organic, fair-trade chocolates to get mother
nature to forgive us for our wrongs, but at least we are beginning to
apologize.
Friday, 7 November 2014
Sketchy Fact #66: Family Ties
Genghis Khan slept with so many women in the places he conquered that 1 in every 200 men alive today is directly descended from him.
Wednesday, 5 November 2014
A Dinosaur Mystery: The Case of the Freakish Forearms
Paleontology
is an art as much as it is a science. When the animals you study mostly died
out around 65 million years ago it can often be tricky to understand the most basic
things about them. For that reason, paleontologists can be prone to some of the
most imaginative theories in all of science. That is to say, sometimes they
just make stuff up. Not that you can blame them. Dinosaurs especially are just
one of those things that people are really excited to learn about. In the world
of science, when you’ve got everyone’s attention, it is tempting to come up
with a good story to tell, even if it isn’t always supported by the facts.
A few
famous and notable mistakes made since the study of dinosaurs
began include the Iguanadon’s spiked thumb being placed on its nose as a horn;
the discovery and unfortunate naming of the BasiloSAURUS, which is actually an ancestor of whales and
not even close to a dinosaur; and the idea that Brachiosauruses spent most of
their time underwater with their heads poking out of the surface to breath.
To be fair
to modern paleontologists, most of the really big goofs happened in the early
years of bone hunting and things are a little more reserved and a little more
open to debate these days… Most of the time, anyway. One exception is the
dinosaur known, inconveniently, as Deinocheirus
mirificus (we will stick with DM for short). The problem with old DM is
that when it was discovered in the 1960’s all that scientists could find were
its two front limbs, but oh what front limbs they were. Muscular and measuring
2.4 meters (8 feet) long, ending in three mean looking claws they were unlike
anything ever before seen on a dinosaur. Since the arms were all they had to go
on, DM’s name literally means “unusual, horrible hands.”
Since it
was unearthed, paleontologists have been theorizing what DM could have possibly looked like. Some
of the more fun ideas include A) a T-rex-like predator with freakishly long arms
to grab fleeing prey and B) something like a reptilian sloth that used its strong
arms to hang from tree branches. The ideas were so imaginative and so varied that
it was clear to even the casual observer that the people involved really had no
idea what they were talking about, which is why DM has spent the last half
century in the dusty storage closet paleontology reserves for its cold cases.
And in that
closet DM stayed until August of this year when researchers published a paper reporting that, at long last, they
had discovered a complete DM skeleton. Finally, crazy notions could be set
aside and DM could be marveled at and respected for the impressive,
chiseled work of nature it was. Unfortunately for DM, when asked to describe
the discovery, lead researcher Yuong-Name Lee said “It turned out to be one of
the weirdest dinosaurs. It’s weird beyond our imagination.” Other researchers
have commented that “… it’s just so freaking weird – we never would have
expected this animal to look so bizarre.” Maybe it’s time to change the name to
Rodney Dangersourus.
It turns
out that DM was huge. Something like 11 meters (36 feet) long and weighed as
much as 6 tonnes. It had a hump on its back, a beak, and hooved feet.
Scientists now believe DM lived in wetlands and the contents of its stomach
suggest it ate mostly plants and fish. And the arms? It is now thought that
they were used to dig through the prehistoric muck in search of good
plant-matter to munch on. So much for snagging fleeing prey at high speeds.
So what is
the lesson in all of this? Something we thought might have been the baddest
predator of it’s time turned out to be a muddy swamp-monster. Yeah, that might
be one way to look at it. The other, much cooler lesson is that dinosaurs still
have the ability to surprise the best minds in the business. When you can shock a profession as imaginative and outlandish as paleontology (did I mention they
used to think stegosaurus had a second brain in its butt?) you are certainly from
a ilk worthy of our attention. In the end, it goes back to a great quote from
geneticist J.B.S. Haldane: “My own suspicion is that the Universe is not only
queerer than we suppose, but queerer than we can suppose.” Or, if you prefer, another quote from the fictional
scientist Dr. Ian Malcolm: Just when you think that nature can’t get any
more screwy, “life finds a way.”
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