Hello this week we've got a lot to cover including a historic space launch
a breakthrough in manmade DNA
and what religion and pornography have in common.
So let's get to it.
It's the end of an era at nasa but also the start of a new one last week nasa's
and discovery
the first of its three retired space shuttles to its final destination
at the National Air and Space Museum.
and in the next week or two a huge step will be taken in the replacement
of the space shuttle program. Early in May the private spaceflight company
SpaceX is expected to launch
its new cargo vehicle The Dragon from Cape Canaveral to rendezvous
with the International Space Station. If successful the Dragon will be the first
private spacecraft
to birth with the ISS and offload cargo The launch was originally scheduled for this
coming Monday that earlier this week SpaceX founder Elon Musk tweeted
that he wanted to spend more time testing the code that the Dragon will
use to dock with the ISS this is how we
disseminate information now apparently lift off is now tentatively scheduled
for May 7 and its marquee contest SpaceX already has a 1.6 billion dollar
contract with Nasa to fly 12 missions to the ISS
but a lot is riding on how this first one goes. In addition it is launching
and getting into orbit successfully SpaceX will also have to prove their
time and space craft can perform some tricky maneuvers before actually docking
essentially taking one long lap around the ISS at about twenty seven thousand
kilometers per hour. If all goes well Dragon will dock on day four of the
mission unloading more than 500 kilograms of equipment
and some nonessential supplies so don't worry it's not like the six astronauts
aboard the ISS
are in danger of running out of water oxygen or anything if the test fails
the plan is for the dragon to stay docked for 18 days at which point it will
return to Earth with 660 kilograms of cargo
which is notable because that more weight than the Russian Soyuz capsules
can carry.
SpaceX isn't the only company that's developing a taxi cargo service for Nasa
but
it's the first to demonstrate that it can launch vehicle into space and return
it safely to earth, which it did in December 2010. The company is also
working on a prototype seven-person crew cabin for the Dragon that could be ready
for testing within a year or two
I'd totally voluntier to be one of Dragon's first passengers but you now
the air sickness
Next big news in the world a synthetic biology a field that we talked about a
few weeks ago
this week SynBio saw maybe it's biggest advance
yet, with news that synthetic alternatives to DNA and RNA can not only
replicate
but also adapt overtime. These man-made alternatives called xenonucleic acids
XNA's have been around for a few years, the ones that were talking about
have the same genetic code is DNA with the bases
A G T and C but the sugars that make up the backbones are different
and they actually make XNA's structurally stronger than DNA.
The first breakthrough came last week when an international team of chemists
said that they created
enzymes that replicate XNA molecules just like the enzymes
that replicate DNA. The team put these polymers enzymes to work
copying DNA into XNA and then use them to copy the XNA's back over and over
This kind of replication is exactly what polymerases are doing with DNA
in your cells right now but it's never been done with anything other than DNA
or RNA in like the history of the world. In another, possibly even cooler
experiment, the scientist tested whether XNA's could adapt under pressure
in this case they wanted to see if random sequences of an XNA molecule
could evolve to bind
to two specific target proteins, they used their new enzymes to produce batches
of XNA segments
and then selected the ones that found their target successfully, those segments
were then replicated by the new
enzymes and the new copies were put to the same task.
After eight generations the resulting XNA sequences had essentially been bred to
bind perfectly with the proteins much like we breed
animals and plants. This research means that life doesn't necessarily depend on
two molecules DNA and RNA
there could be all kinds of other maybe simpler maybe better ways of storing
and sharing genetic information in the universe
so when we find extraterrestrial life, and we will
The code that it will carrying its alien blood could look a lot like XNA
Finally new discoveries about two things that make your brain turn off
religion and porn. Let's start out with the porn because that's the kind of day I'm having the
Journal of Sexual Medicine reports this week that when women watch porn
they stop using their visual cortex the part of the brain that's responsible not
just for observing but also processing what's observed. I don't know if you've seen porn
but there's not a whole lot there to process.
Anyway, 12 women were given PET scans have their brains while they watched 3 videos
the first was a totally unsexy nature documentary the second showed some kinda
r-rated action and the third
was what the team of Dutch physicians called high-intensity erotic film only
when the woman watch the porn did the blood flow to their visual cortex drop
dramatically
the researchers believe that this is because the blood was redirected to
regions of the brain involved in sexual arousal
and also because porn and I quote
"Does not require precise scanning" Like I said not a lot to actually process there the
researchers noted though, that the visual cortex is also the region of the brain
associated with anxiety
which might suggest that sexual arousal can quiet anxious behavior. Sex good,
anxiety bad. As for religion let me be the one to tell you, you don't
have a god spot that's the term some researchers have been using to describe
a hypothetical region of the brain
supposedly associated with spirituality, but research at the University of
Missouri has confirmed
earlier studies that say that no such spot exists
instead spirituality is just something that your whole brain
does together. Still some regions of the brain contribute to this more than
others. Lead scientist Brick Johnstone, what an amazing name
anyway he studied 20 people with severe injuries to the right parietal lobe
that's the area just above your right ear that's responsible for things like
spatial relationships and self-awareness
He found that subjects with the most severe injuries there, felt most associated with
and closest to a higher power. This kind of makes sense because the whole right side
your brain tends to be dedicated to you and for looking out for yourself. And a lot of
research has found that monks and nuns and the like
tend to use that self centered part of their brains a lot less. The main thing is;
there's no like structural part of the brain that's responsible for religion and
spirituality. Thanks for watching this episode of scishow news, if
you want more news and other science stuff or to be a smarter person you can go to
youtube.com/scishow and subscribe
And if you have questions or suggestions for us. You can reach us on Facebook or
Twitter or of course
in the comments below. We'll see you next time.