Bill Nye the Science Guy invented an improved version of ballet slippers after filming a show at a ballet studio and noticing the ballerinas had bloody feet.
Friday, 26 September 2014
Tuesday, 23 September 2014
Relativity – Just the Weird Stuff, Volume 2: Move Your Mass
Here at Sketchy Science we aren’t much for cliff hangers. Generally
speaking, we like to lay all the cards on the table and leave you with a
well-rounded understanding of a topic before disappearing for another week.
With the topic of relativity, however, we thought it best to break things up.
Few subjects can blow a mind like relativity and it is easier to remember
things in chunks as opposed to a giant blob of information. With that in mind,
this week we are picking up where we left off last week. So, if you resisted the urge to just google things for yourself and actually waiting for this week’s article,
join us as we explore the weighty side of Einstein’s theory.
A Simply
Complicated Equation
First off, weighty is the wrong word. We are talking about mass. Mass is
the unimpeachable number assigned to how much heft and object has anywhere in
the universe whereas weight is how much mass it has on Earth. In our day to day
lives, these words mean the same thing, but to keep things properly scientific
we will use the word mass from here on out since these ideas aren’t bound to
our little blue planet.
Everyone has at some point come across Einstein’s famous equation E = mc2
and a few of us even know that it means energy (E) is equal to an objects mass
(m) multiplied by the speed of light (c) squared. The speed of light is an
incredibly large number, so you can appreciate that squaring it gives you
something incomprehensibly huge. Basically the equation is a mathy way
of saying that all objects contain a lot of energy and that mass is just a formof stored energy.
Last week we talked
about the speed of light as the cosmic speed limit and how nothing can move as
fast or faster than light. An interesting and unexpected upshot of this is that
as objects accelerate through space, they gain mass. To understand this we need
to go back to E = mc2.
Get
Energized
It is easy to understand that the faster an object moves, the more
energy it has. If you don’t believe me, go stand in front of a fastball thrown
by a professional pitcher. We have already said that according to Einstein’s
equation, mass is basically just energy waiting to happen. For this reason,
stored energy is often referred to by scientists as inertial mass. Another way
of looking at inertial mass is as the amount of resistance an object has to
going faster. It is harder to push a car than it is to push a bowling ball, and
it is harder to push a bowling ball than a marble. In each case the object has
more mass, more stored energy, and more inertia.
Since objects aren’t allowed to travel faster than the speed of light
they need to resist gaining speed when they get too close the magic number of
300,000 km/s (186,000 mps), otherwise known as light speed. To do this, they gain mass. For an object to move at the speed of
light it would need to have infinite energy which is also infinite
mass and infinitely impossible.
Harnessing
the Higgs
You might remember hearing on the news a while back about scientists working on the
Large Hadron Collider discovering something called the Higgs Boson and it being
a big deal. The reason for the hype is that for a long time scientists have
thought that the Higgs Boson could be the part of an atom that gives it mass.
Observing this piece of the puzzle is the first step on the road to
manipulating mass to the point where we could potentially create something
capable of moving faster than light and it all goes back to E = mc2
.
Science is an ongoing process of observing and thinking and theorizing
and building on the work of past scientists. Its progress depends on testing
ideas and inching closer to major breakthroughs by making small discoveries and
putting the pieces together. Einstein’s equation built the framework that
allows modern scientists to understand how light speed travel could work and by
digging deep into each piece of the equation, they move us all closer to what
might right now seem like science fiction.
It may not seem like it, but knowing that you gain mass when you get up
to make that sandwich in a way that has nothing to do with calories could one
day lead to humanity exploring the stars. Relatively speaking, that is pretty
awesome.
Friday, 19 September 2014
Sketchy Fact #58: Caught in the Crosshairs
Spider silk was used to make the crosshairs in rifle sites until the 1960's because it is 40 times finer than human hair.
Wednesday, 17 September 2014
Relativity: Just the Weird Stuff, Volume 1 – Time Travel
Einstein’s theory of relativity has a reputation for being complicated.
Most of us outside the world of physics will never sit down and really try to
figure out the details, partly because it is hard and partly because knowing
that we gain a tiny amount of weight every time we move has the potential to
play havoc with a person’s self-esteem (not to mention your motivation to get
off the couch). However, understanding at least a little bit about some of the
universe’s weirdest phenomena will really help put things in perspective.
You’ll stress less about your printer not working properly if you remind
yourself that in another dimension you’ve probably already smashed it.
Time
Dilation
Relativity is an especially cool concept to ponder. Take, for example, the fact that if you were
standing on a very weighty object like the sun and you were able to look
through a telescope through the window of a spaceship speeding past at a crazy
velocity, time on the spaceship would appear to be moving in slow motion relative to what you are experiencing
from your hot seat.
This effect is called Time Dilation and it isn’t just theory, it is
something scientists have observed and measured in the real world. In October
of 1971 physicists Hafele and Keating sent a super-accurate atomic clock on
high-speed plane trip around the world, twice. Exactly as Einstein's equations
predicted, the very worldly clock had lost 59 nanoseconds when it landed
relative to a synchronized clock on the ground.
Time Dilation happens on a much smaller scale every time you walk from
the living room to the kitchen to make a sandwich. Relative to your friends who
went sandwichless a smaller amount of time will have passed for you on the
order of 0.000000(something very small) nanoseconds.
Deeply
Unsatisfying Time Travel
The reason for this warping of time, believe it or not, is the speed of light. Light is the fastest thing in the universe and the universe
likes keeping it that way. For that reason, things get weird the closer you get
to travelling at light speed (300,000 km/s or 186,000 mps).
To borrow a famous example, imagine that there was a train track that went in a straight line
around the equator and that the train that rode on it was capable of
travelling at 99.9999% the speed of light. Now imagine that you are a rider on
that train sitting at the back of your car. At some point you are bound to get
tired of looking out the window at the endlessly sickening blur of trees and
people and you might decide to go to the bathroom, which is at the front of the
car.
As you walk forwards on the train which is traveling at near the speed
of light, your walking speed gets added to the speed of the train much like the
speed of a slushy thrown from a moving car gets added to the car’s speed. If
you walk briskly enough, this could mean that you break the cosmic speed limit
by traveling faster than light. The universe can’t abide this and the only way
to prevent it is to make time slow down for you. The closer the train travels
to the speed of light, the slower time moves for those on board.
The side effect is that you are able to travel forwards through time. If
you rode the light train travelling at a certain percentage of the speed of
light and disembarked one year after setting out, 100 years could have passed
for everyone not on the train. As cool as that is, there is no way we know of
that will definitely let you travel in the opposite direction. So unless you
don’t mind everyone you know dying while you ride a train, it’s probably best
to save the cost of the ticket.
Come back next week for part two where we explore mass side of the
equation… And maybe lay off on the cheeseburgers until then.
Friday, 12 September 2014
Sketchy Fact #57: Killer Coconuts
On average, falling coconuts kill 15 times the number of people (150) each year that sharks do (10).
Wednesday, 10 September 2014
Ebola: The Good, The Bad, and The Gorillas
By now you have probably heard that there is a massive outbreak of Ebola
virus going on in West Africa. Even if you have been living under a rock
somewhere in the jungle it is likely that Ebola is on your radar, partially
because that is where Ebola tends to hide out. As we head into the sixth month
since the outbreak began, it is even starting to worry people far outside Africa, as infected people are transferred to facilities throughout Europe and North
America for treatment, potentially exposing millions of more people to the
disease. But before we all barricade ourselves in our bomb shelters, it is
important that we understand what is actually going on.
The media tends to exaggerate things. As we all know, getting good
ratings is often even more motivating than telling an accurate story. With that
in mind, it is important to take a look at the science behind Ebola.
Unfortunately, one thing the media has gotten right is that Ebola virus
disease is fantastically fatal to humans. As we learned back in Sketchy Fact#47, rabies is the deadliest virus on the planet with a 99.999% fatality rate.
Ebola is one of the few viruses that plays in that same ballpark.
There are 5 different species of Ebola virus and each has its own potency.
Reston Ebolavirus is the least dangerous to people, with zero fatalities (you
really don’t want Reston if you’re a macaque, however). Sudan Ebolavirus is the
middle of the pack killer, with a fatality rate between 50 and 60%. The really
scary form of the virus is Zaire Eboloavirus, with a historical fatality rate
of around 90%. The really bad news? The current outbreak is the Babe Ruth of Ebola.
Ebola is named after the Ebola River in the Democratic Republic of Congo,
near the location of one of the first ever outbreaks and now possibly the least
desired honeymoon spot on the planet. First discovered in 1976, Ebola is a
relatively new scourge on the super-deadly disease circuit. Since the first
few small outbreaks in the 70’s the virus has popped up sporadically, all but
disappearing until a string of fatal outbreaks in the mid 90’s. However,
nothing compares to the current outbreak. Before 2014 the deadliest ever Ebola
outbreak occurred in 1976 and killed 280 people. So far this year, over 2,000
people have died.
Ebola is so deadly because of the way it spreads through the body,
actually using a person’s own immune system against them. When the virus
infiltrates a cell it takes over the cell’s ability to reproduce DNA, hijacking
it to make copies of its own genetic code. Ebola is an RNA virus, meaning that
instead of the double helix DNA ladder we are all used to, there is only one
strand to be copied. This makes the process fast and fierce. Once the cell is
overwhelmed with virus is bursts and the immune system kicks in.
The immune system sends out cells called cytokines to attack the virus.
However, where most viruses are overwhelmed like a physics major on a date with
a cheerleader at the mere site of a cytokine, Ebola has the charisma of George Clooney. Rather than being
destroyed by the cytokines, the virus hitches a ride and uses them to spread around the body into the tissue that makes up the walls of blood vessels. Ebola next attacks the
liver, killing more cells and stopping the immune system's alarm chemicals from being cleared
from the blood. The result is that the immune system keeps sending out troops
and Ebola keeps bringing them over to the dark side. The outward symptoms resemble
a really terrible flu including fever, vomiting, and diarrhea. The latter two symptoms including the presence of blood in the later stages or the disease.
As the virus eats away at the circulatory system blood clots form all
over the body, clogging arterties. Eventually organs begin to shut down and blood vessels rupture
causing massive internal bleeding. Contrary to popular belief, and in opposition
to what the historic misnomer “Ebola Hemorrhagic Fever” would lead you to
believe, most patients don’t bleed externally. Instead bruises form as blood
escapes vessels within the body. Most people don't die of blood loss, however; it is organ failure that gets them. Ebola can kill you within 7 days of getting into your
body.
This is all rather terrifying news, but there is hope. Ebola is spread
by contact with bodily fluids, so to become infected you need to be closely
caring for, or intimately interacting with, an infected person. The reason the
virus has been able to spread so effectively in Africa is that local customs in
rural villages at the centre of the outbreak involve close contact with the
bodies of recently dead family members. On top of that, the health care system in many African countries just isn't equipped to contain an epidemic. Another deeply uncomforting reason the
virus isn’t likely to cause a global pandemic is that it kills people very quickly,
leaving it little chance to infect new hosts.
Ebola, like rabies, is thought to use bats as its natural reservoir. It lives in peace causing no trouble to the bat or anyone else under normal circumstances. The
problem, or “spillover,” occurs when people eat the bats as bush meat or when
another animal, say a gorilla, stumbles upon a piece of fruit that an infected bat was
recently gnawing on. In fact, Ebola is as scary for gorillas as it is for
people. It is thought that since 2000 Ebola has killed over 5000 gorillas in
central Africa, severely damaging an already threatened population.
So there it is, the truth about Ebola. Here’s hoping that the effected
countries are able to educate people soon enough to stop the current outbreak
before the death toll gets much higher. From there we can worry about educating
the gorillas.
References:
Friday, 5 September 2014
Sketchy Fact #56: Into the Freshwater Abyss
Lake Baikal in Siberia is the deepest and oldest lake in the world at 1620 meters (over a mile) deep and around 25 million years old. It holds about 20% of the world's liquid fresh water.
Wednesday, 3 September 2014
Messing with Motor Function: The Science Behind ALS
In case you missed our post last week and
in case you’ve been living under a rock for the past month, the ALS Ice Bucket
Challenge has reached a pinnacle of virility not seen since Rebecca Black gave
us a new way to usher in the weekend. However, unlike the meaningless funny
stuff that usually turns up on the internet, the Ice Bucket Challenge has done
an incredible amount of good. Apart from raising awareness of ALS (amyotrophic
lateral sclerosis), nominators and nominatees have donated over $100 million to ALS research
as of this writing. Compared to the $2.1 million raised in 2013, the past month
has been an icy flood of cash.
But what is ALS any why have we all so
enthusiastically decided that we need to drown it out? Most of us know that
baseball hall of famer Lou Gehrig suffered from the disease and eventually gave
his name to its colloquial identification. Some of us even know that
world-famous physicist Stephen Hawking lives with the disease to this day. But
what causes ALS? What does it do to a person’s body? And what can be done to
stop it?
ALS is a disease of the motor neurons.
There are two kinds of motor neurons: upper motor neurons (the ones in your
head) and lower motor neurons (the ones everywhere else in your body). ALS
starts off my damaging either the upper motor neurons, preventing them from
sending signals to the spinal cord, or the lower ones, preventing them from
taking messages from the spinal cord to the muscles. In the latter case,
muscles in one part of the body will become weak or clumsy. In the former case
a person will become more generally weak and uncoordinated.
The real problem with ALS is that it
spreads and intensifies, eventually leaving a person paralyzed and without
control of any of their voluntary muscles. Mercifully the disease tends not to
effect involuntary muscles like those in your bowel and it often spares the
muscles that control eye movement which is what allows Stephen Hawking to teach
the rest of us about black holes. He uses eye movements to type academic papers
and books in a monumental feat of patience. As ALS progresses it impacts
a person’s ability to swallow and breath normally, often leading to death by
choking.
Scientists aren’t sure what causes ALS
generally, but they are aware of a type that runs in families. Research has shown
that a mutation in the SOD1 gene is present in 20% of people with familial ALS.
SOD1 directs the body to produce an enzyme that protects motor neurons from
harmful unstable molecules called free radicals. The mutation removes this protection and causes neurons to break down. If a person has a parent with this gene
mutation, there is a 50% chance they will develop ALS. Thankfully, the sporadic (non-familial) form of the disease is far less common. On average only 2 in every 100,000 is
struck with ALS, usually between age 40 and 60.
As you have probably figured out by the
existence of the Ice Bucket Challenge, ALS has no cure… yet. While modern
treatments and technologies can help prolong patients’ lives by a few months to
a few years, most people with ALS pass away within 3 to 5 years of being
diagnosed. The notable exception is Stephen Hawking. Through a combination of
medical intervention, help from computers, and sheer force of will Dr. Hawking
has lived with ALS for over 45 years.
Modern research is focused developing gene therapies to treat mutations that can cause ALS or aims to develop chemical
therapies that increase the production of antioxidants and neurotrophic factors
in the body to help build and protect muscles cells. Stem cell treatments are
also showing some promise. In 2008 researchers were able to take stem cells
from the skin of 2 people with the harmful mutation to their SOD1 genes and raise them to produce healthy motor neurons.
One day researchers hope to be able to grow
enough motor neurons to transplant them into patients and reverse the disease's
progression. The best current treatments can do is slow down the spread of ALS through the body. In rare cases ALS can burn itself out, reaching a
certain point and just stopping. Scientists don’t understand why this happens
but research on people for whom this is the case may also help develop
treatments.
In order to do the research needed to
better understand ALS and develop treatments, scientists need money. They get
that money from organizations like the ALS Association, who rely on donations
from the general public. So next time you see a video of one of your friends
dousing themselves in water, throw them a like. And if you are nominated to do
the challenge yourself, do it and make a donation. A little discomfort for you
could mean a whole lot less for someone else.
Labels:
ALS,
genes,
health,
mutations,
neuroscience,
stem cells
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