Monday, October 3, 2016
Friday, September 30, 2016
Elon Musk and SpaceX's Plan for Mars
Yesterday at the International Astronautical Congress in Guadalajara ,
Mexico , billionaire and visionary
space entrepreneur Elon Musk announced a detailed plan for putting humans on
Mars. While it's quite ambitious and entails some unorthodox but surprisingly
realistic ideas, the fact that it comes from Elon Musk, the founder of SpaceX,
is significant.
There seems to be every indication that he's going to make
it happen. If his past activities are any indicator, this is not pie in the sky
dreaming but could become reality. You see, he's said all along that he founded
SpaceX with the specific end game of going to Mars in mind. And now, years
later, SpaceX is no lightweight start up. And now he has a coherent plan for going
to Mars.
What was notable about his talk was that Musk revealed a lot
of specifics about the engineering and science of just how his company is going
to do this, to the point of delving into the function and testing of a rather
impressive carbon fiber fuel tank SpaceX built for the project and even
detailed his concerns about going to Mars himself due to the fact that he wants
to make sure his company doesn't end up under the control of for-profit
investors should he die in an accident. At the very least, Elon and SpaceX has
gone "all in" with this one.
Step one of the plan is to build a suitable rocket. This
involves an intermediate step. SpaceX's plan to develop a rocket that can take
us to Mars has been in the works for some time. Known as the Falcon Heavy, this
rocket has been designed from the outset to carry humans and will be fully
capable as a super heavy lift launch system that can reach the Moon or Mars. In
addition, it can carry significantly larger payloads into low earth orbit than
we can with current rockets, to the tune of 54,400 kilograms. The first launch
of one of these rockets, which really are a modified version of the Falcon 9
rocket, is expected in early 2017.
That's not long from now, and it ushers in a new age of successive
very large rockets including NASA's Space Launch System or SLS, which will
surpass even the venerable Saturn V of Apollo fame, but Musk intends to outdo
even that. So very soon, at least, we will once again have the capability of
sending humans beyond low earth orbit. Congratulations to SpaceX and NASA indeed.
But Musk's plan doesn't stop there.
Musk's timetable to go from the first launch of a Falcon
Heavy to landing a human on Mars is about ten years. Now, one possible snag
with his plan is funding. He envisions a sort of public and private mix of
funding sources, but these have not yet been fully secured. There are many ways
he can do this, including crowd sourcing and using his own assets and money
along with the profits from SpaceX. That might seem a stretch but on the other
hand, it's Elon Musk and he's shown a certain ability to get things done.
Using the Falcon Heavy, the plan initially entails sending
research spacecraft to Mars based on the Dragon design. Windows to launch to
Mars which aligns with earth favorably every 26 months will each see a
spacecraft launch starting with the first in 2018, less than two years from
now. These missions will collect data needed for landing humans on Mars and
moving to the next step. But then it gets crazy.
If SpaceX is successful, which while skeptical I certainly
hope they are, this plan is no simple hop over to Mars to take a look around
and leave. Musk's plan is far more ambitious. Shockingly so. In Guadalajara ,
he laid out plans for an all out self-sustaining colony and gave engineering
specifics about an even larger rocket and spacecraft to be launched in 2022
that is specifically designed to found a permanent, self-sustaining colony on
Mars that could result in millions of people living on that planet terraforming
it into a second earth. Elon Musk wants to make us into a multiple planet
species, and that's quite an ambitious goal indeed, but also sensible if he can
make it happen.
This larger rocket and spacecraft is called the Interplanetary
Transport System and it appears that SpaceX has already completed much of the
design work. This is an unbelievably titanic launch system designed to carry
100 people and all of their supplies, gear, and separately the fuel needed to
get to Mars.
How the system works is relatively straightforward. The manned
spacecraft launches atop a reusable stage that carries it into a parking orbit.
Then the rocket stage returns to earth to pick up a similar spacecraft adapted
for refueling the manned spacecraft. Shortly after being mounted on the same
first stage, the fueling spacecraft launches again delivering its payload to
the manned spacecraft. It then loads the fuel onboard, returns to earth, and the
manned spacecraft disembarks for Mars.
Musk described this spacecraft as fun. It certainly appears
spacious, even if carrying a hundred people. But he envisioned that it might
have a restaurant, quarters, and all manner of comforts making it seem more
like a cruise ship than a spacecraft.
Once it arrives, it will enter the Martian atmosphere using
a heat shield, then flip around and fire a landing rocket carrying it safely to
the Martian surface. Once landed, the humans will disembark and set up a colony
and a fuel depot. This depot would manufacture fuel on Mars to relaunch the
spacecraft and return it to earth to be used to pick up more passengers and
transport them to Mars, along with anyone with cold feet that wished to return
home.
All the while, SpaceX will build more spacecraft and launch
systems ultimately allowing for large numbers of people to go to Mars to
colonize, build businesses, create a city on Mars and eventually make it
self-sustaining. His time table for this is between 40 to 100 years before a
self-sustaining colony can be established using a fleet of as many as 1000 of
these spacecraft.
He envisions it how the west of the United
States was colonized. California ,
for example, was a sparsely populated frontier until the Union Pacific Railroad
was built, and now it's one of the main centers of American culture and
population. The existence of the railroad was pivotal in establishing that, and
Musk believes that his Martian transport system will serve a similar role. There
were people that didn't believe in the construction of the railroad at the
time, arguing that very few people lived in California
and there was no point. They turned out to be epically wrong. Might that happen
with Mars too?
Well, part of that question will be resolved with costs. If
it's expensive to go to Mars, then it's not going to happen other than an
international government project to send a few astronauts to set foot there,
pat ourselves on the back and then leave. But if it's cheap, then that changes
the equation.
Musk claims that his system will allow a person to relocate
to Mars for less than $100,000 U.S. dollars. That sounds expensive, but it's
very cheap compared to going to the International Space Station. In 2001
multimillionaire Dennis Tito went to the ISS and had to pay the Russians 20
million dollars for a week's vacation. In comparison, a hundred grand is so
cheap that it could make sense for business people wishing to make money from
resources on Mars or selling pizzas there.
In short, SpaceX's plan is to simply provide the transport.
They want to be the railroad. Humans will found the colony as they will using
Mars's natural resources. These are pretty good, actually, at least for
founding the colony. There's no shortage of water on Mars, ice is everywhere that
can be melted. Further, the planet's atmosphere is mostly carbon dioxide, which
means oxygen can be extracted from it. There's also some nitrogen there, and
soil that almost certainly can be used to grow food. But can you make money
from residing on Mars? That remains to be seen.
But the Interplanetary Transport System isn't just limited
to Mars. By building a fuel production depot at Mars, essentially a gas
station, a manned mission to Jupiter becomes possible. By locating another
depot on the moon Europa, then Saturn comes into play. By building a depot at
Enceladus, you can go even further. This system is designed to allow humans to physically
go literally anywhere in our solar system. That's an amazing idea if you think
about it, given that today we can't leave earth orbit with manned missions.
As an aside, Musk mentioned another interesting possibility.
To generate money for his endeavour, he explored the possibility of using the
ITS for transporting goods on earth. If you were in New
York and had a load of tomatoes that you really
wanted to get to Paris very
quickly, the ITS rocket could certainly do it.
It could theoretically cross the Atlantic
in less than 15 minutes. It would be a very expensive batch of tomatoes to
deliver, but needless to say that such speeds, if there is a market for them,
would prove very useful for the human race and very different from what we have
now. And Musk intends to accomplish this within just a few years.
So once a colony on Mars is established, what will it be
like? I'll leave that for a future video as Elon Musk's plan develops, but I
hope we do it with better planning than we did here on Earth. I'm confidant we
will, and maybe some day as the cultures of the two planets diverge we will
learn from them as they learned from us.
Sunday, September 25, 2016
Proxima Centauri b Update
Proxima Centauri B has recently shot to the top of the list
as far as interesting exoplanets go. Not only is it the closest exoplanet to
our solar system, it's also about the size of earth and within the habitability
zone of its star. This is potentially earthshaking because this planet is so
close to us that it's possible, maybe even probable, that some day humans will
set foot on it or even colonize it, assuming that it's uninhabited of course.
Unfortunately, at least until the James Webb Space Telescope
launches, we don't know much about this world other than what we can infer. We
also don't know much about the conditions of life arising in a red dwarf star
system. But a recent paper by Laura Kreidberg and Abraham Loeb of Harvard
University gives some tantalizing
hints of what Proxima B might be like.
The paper's overall purpose is to present the case that the
James Webb space telescope will be able to determine if there is liquid water
on Proxima B. This is the first step in establishing whether life can exist
there. Where there's water, there could be life. But on Proxima b, it's a bit
more complicated than that and nothing is guaranteed.
Firstly, they lay out that this planet may have no
atmosphere at all. It orbits a star very different from the sun and it orbits
it very closely in comparison to earth. More, it's probably tidally locked
which means it's like our moon, one side of the planet always faces its star.
This creates some unique conditions where one side of the planet is always in
night and one side is always in day. That means quite a very unearthlike mix of
a permanently scorching hot day side and a frozen solid night side.
With one side always in night, that means that the planet's
atmosphere may have frozen out and locked itself up as ice on the dark side. If
so, that would mean that life on this world is highly unlikely. But it also
makes it a target for terraforming if we ever make it there. Frozen out
atmospheres can be melted and restored, which is one of the main things we'd
have to do if we were to ever terraform Mars and make it habitable for humans.
But if it does have an atmosphere, the researchers point out
that atmospheres tend to redistribute heat. Warm air moves around with wind and
weather, so the dark side of Proxima b may just be warm enough to have
prevented an atmospheric freeze out. If so, then we're back to an environment
that can have liquid water on the surface of the planet.
But there's another problem, Proxima b is so close to its
star that it would be subject to stellar erosion of its atmosphere. The solar
wind and radiation might literally have blown the planet's atmosphere off into
space. That alone may have been enough to deprive this planet of an atmosphere early
on before life had a chance to arise, or it may have survived but we just don't
know enough yet to say. The good news is that we'll know a lot more in just two
years with the launch of the James Webb telescope.
While Proxima b is too close to its star to directly image,
it's year is only 11.2 days, the James Webb Space Telescope will be powerful
enough to tell us much. We should be able to use the JWST to detect the
distinctive infrared emissions that would be produced by the planet and watch
how it changes as it orbits Proxima Centauri. From those observations, we
should be able to determine if it has an atmosphere and how it's redistributing
heat, and by extension if it's warm enough for liquid water there.
But as far as life goes, other factors may also play a role.
One of these would be the presence of a moon. Life on earth is thought to have
arisen in tidal pools. Tides are caused by the moon. No moon, no tides, and
that changes the equations on whether life can arise on a planet. Other factors
include the chemical makeup of the atmosphere if it exists, the geology of the
planet, weather, magnetic fields, plate tectonics and so on.
But in a best case speculative scenario, Proxima B would be
a world that has a ring of habitability rather than a global habitability like
earth. If life exists there, it would be centered on the twilight zone of the
planet where the light is not so strong as to create a permanently lit desert,
but not so weak as to prevent liquid water. This kind of a habitable world is
sometimes referred to as an 'eyeball planet'.
But if it did have life, what would it look like? Well, if
such a planet had foliage, it would need to adapt to a completely different
light profile than earth. As a result, instead of the distinctive green of
earth's planet life, leaves on Proxima b would probably be black. Given the
environment, animals would probably evolve to rely on seeing infrared rather
than visible light. But it may not be possible for that sort of life to exist
on that planet and perhaps the best we could hope for would be algae and
microbes.
It has been suggested that worlds such as Proxima b, even if
it did have liquid water, it would have conditions very different from earth
and would present different challenges to life. These include permanent
torrential downpours in certain areas of the planet and constant high winds
that scour the planet's surface. The presence of an ocean may change that
however, and allow for a protected underwater zone where life could flourish.
Another factor would be the presence of geothermal vents underneath the frozen
side of the planet and the potential for a protected liquid water environment
under the ice.
So there you have it, while we may not know much about
Proxima b yet, the James Webb Space Telescope will be powerful enough to reveal
much more. In just two years, we should have a better understanding of our
nearest exoplanet neighbor and determine whether it is to be the first
interstellar object humans will visit.
Friday, September 23, 2016
Elon Musk wants to colonize Mars!
http://www.bloomberg.com/news/articles/2016-09-23/elon-musk-to-outline-his-plans-for-mars
Best of luck to him. We need more people in this world that think big like Mr. Musk.
Best of luck to him. We need more people in this world that think big like Mr. Musk.
There is no now
Humans very much depend on the present. Everything we do in
life is done with the understanding that we're doing it right now, whether
we're hugging a friend or recording a YouTube video. We do it in the now and
then it becomes the past. But it might surprise you to find out that in
science, what we think of as "the present" doesn't actually exist.
Only the past and the future do.
When we look into the night sky, we are seeing the past.
Often the distant past. If you look at the Andromeda Galaxy which is just barely
visible to the naked eye in a dark location, you are seeing it as it was 2.5
million years ago because light travels at a rate of 186,000 miles per second
and it takes that long to travel the immense distance between the two galaxies.
This is also true for an object in the room with you. When you look at your phone,
you are seeing it as it was a tiny fraction of a second ago, not as it is right
now. Light, or information, takes time to propagate no matter the distance.
This means that in any direction you look, you are always seeing
the past no matter what. You are not seeing the now. In fact, it's physically
impossible for you to see the now. But it gets worse. It's also impossible for
the now to exist in your brain because it also takes time for impulses to
travel along neurons. And, this doesn't happen at the same rate for everyone.
All of our brains are unique. Each human brain varies in the
time it takes to process the information it receives from the outside world.
This means that your now is different from my now, even if by just a fraction
of a second. Perception is a deep rabbit hole indeed because the differences
between brains covers more than just processing time.
Diagnosable conditions like color blindness aside, you
probably do not see the same colors that I do. How you perceive red is likely
different from how I perceive it, but since there's no way to describe the
color red then there's no way to know -- at least until brain to brain interfaces
become available. Likewise, you don't experience the present at the same time
that I do. The difference is miniscule, a matter of milliseconds, but it's
there.
Intuitively we think of the present like a sandwich filling.
It's wedged between the past and the future, but in reality it's not. It's
actually a completely fake construct of our brain. You can see this by thinking
about what a moment in time really is. When you think about it, the present has
no duration. There is no length of time involved, you're just conscious moving
from one moment to the next seamlessly. We have to artificially make a duration
for it with a clock. In other words, our perception of the present is just a
construct of our brains. It doesn't really exist.
Yet we live our entire lives in this strange juxtaposition
of having memory of the past and expectation of the future and are led to believe
that we're in the present at all times by our brains.
But what is time? If you think about it keeping track of
time is really just keeping track of change. If nothing ever changed, time
would seem to have stopped. As a result, there would be no present because
there would be no change from which to judge it. If nothing changed in your
brains and your neurons simply stopped firing, i.e. stopped changing, the
present would cease for you. So would consciousness. Are time and consciousness
linked? In some ways, yes. At least our notion of time is.
But does time really exist? Well, in some ways it does, and
in some ways it doesn't. Time is thought to be a dimension, one that we always
move forward in. We don't actually know why that is, but I'll leave that for a
future video. If you're talking about time as we perceive it, then it doesn't
appear to exist. But if we're talking time in the sense of physics, it very
much exists. And, whatever it is, it's linked to space itself, hence
space-time. It can speed up or slow down. It ticks at different rates depending
on where you are as far as gravity is concerned and how fast you are moving. If
you're just about to fall into a black hole, then time nearly stops -- for
someone observing you. For you, it seems to tick normally. That's because
everything is relative.
That throws another wrench into the works of perception. That
wrench is Einstein's theory of Special Relativity. Einstein realized that
because everything is relative, two different observers will perceive events
differently depending on where they are. For example, if you were in orbit
watching the earth below you might see two train wrecks, one in Sweden
and one in Argentina .
To you, they appear to happen at exactly the same moment. But if you were at a
different angle in orbit, they would appear to happen at slightly different
times because of the change in distances the light has to travel.
This is because the observation of events is relative to the
distances and motion involved and thusly the question of when they happened is
also relative. One person believes the events were simultaneous because she
observed them to be, and the other does not because he observed them and saw
something different. There is no such thing as an absolute frame of reference.
This whole idea gets even stranger when you dig into
philosophy. If the present doesn't exist, and the past is that which already happened,
and the future is that which has not yet happened, then where exactly are we? If
you've watched my video "Is the universe real? Or is it a computer
simulation", you'll know that the universe essentially doesn't exist if
you aren't looking at it. If you remove intuitive notions of time and space, that
idea gets even more murky. There is no when, and there is no is, there is only
consciousness observing changes in space. That constitutes everything we
experience from our birth to our death. But let's take it a step further.
There is actually no way to prove that anything exists
outside your own mind. The only thing you can prove to yourself is that you
exist, everything else could be an illusion. And when you alter perception just
slightly, this becomes readily apparent. Mind altering substances alter the
brain's perceptions and thusly things that do not exist for you and I, do exist
for the person under the influence. Someone on LSD may see a giant blue coyote doling
out words of wisdom and completely believe that it's there, whereas the
onlooker sees nothing. The person tripping can't prove that the coyote exists,
but he certainly thinks it does -- at least until the effects of the drug wear
off.
But, that's a two-sided coin. A sober person also can't
prove that what they are seeing is real to anyone else. This is because every
piece of information you get comes from your senses. Senses can be fooled by
fooling the brain, or making it malfunction. This means that to get anywhere in
life, you must assume that what you are seeing is real. And likewise, the rest
of us have to assume the same thing. This means that existence itself is based
fundamentally on an assumption.
So that brings us back to the present. If the present isn't
real, and the past is already gone and the future isn't here yet, and
perception is different for everyone . . . how does all of this manage to work?
I have no idea. As Einstein said, "People like us, who believe in physics, know that the distinction
between past, present, and future is only a stubbornly persistent
illusion".[
Tuesday, September 20, 2016
Why is Pluto Emitting X-Rays?
Recently a group of astronomers have found a new X-Ray
source in the universe. This is nothing unusual, the universe is full of X-Ray
emitting stars, galaxies, and the like. But in this case the source is
unusually weird. They're coming from the planet Pluto.
Now, Pluto presenting us with something puzzling is nothing
new. Ever since the New Horizons probe passed by and explored Pluto last year
the planet has tossed one enigma after another at us ranging from the planet
being geologically active to the planet having an escaping atmosphere that is
partly depositing itself on its main moon.
But these new developments may top even those mysteries.
Researchers Carey Lisse and Ralph McNutt and their colleagues using the Chandra
X-Ray Observatory have found that Pluto, a frozen Kuiper Belt object, is
emitting X-Rays. This is unique for the outer solar system, the furthest planet
known to be emitting such things is the gas giant Saturn. Everything else is
quiet, even the ice giant planets. Very mysterious indeed, but we do have some
ideas on how this can be happening.
Planets, even outer minor planets, are bombarded by the
solar wind that streams off the sun. What's interesting however is that Pluto
lacks a magnetic field and has no apparent way to produce X-Rays on its own.
But we do have a clue. Comets produce X-Rays when the gaseous tail they emit
interacts with the solar wind. Pluto seems to be doing the same thing somehow,
but there are problems.
Pluto is very cold. But it's still exposed to the sun and
heat causes gases to evaporate and create an atmosphere, though this atmosphere
seems to freeze out depending on where Pluto is in its orbit. As the sun heats
those gases with the ionized particles of the solar wind, they react and an
X-Ray is emitted. Seems straightforward. But here's the mystery, the X-Ray
emissions at Pluto are significantly more powerful than they should be and are
at odds with the findings of New Horizons. The spacecraft's measurements
indicated that the solar wind is 40 times too low to create the amount of
X-Rays that Chandra detected.
That would suggest that Pluto not only has an atmosphere,
but also a substantial tail somewhat like a comet. Just such a thing was
seemingly detected by New Horizons, but again seems significantly weaker than
it should be to produce all those X-Rays, though there are other indications it
could be. Another possibility is that interplanetary magnetic fields might be
the culprit and are focusing the solar wind around Pluto. Still further, a
torus of gas centered on Pluto's orbit might do the trick.
The theories abound and no doubt will multiply, and this is
especially interesting since this observation using Chandra was originally met
with much opposition from the scientific community and almost didn't happen.
Few thought Pluto could emit X-Rays. Why devote telescope time to a wild goose
chase? In this case, the goose was easily caught it seems.
But we won't know what's going on here for sure until more
powerful and accurate observations can be made of the X-Ray emissions. But
chalk yet another one up for Pluto, it's mystified us yet again which it's done
repeatedly for the last year. Personally, I suspect it's just taking revenge
for having its planet status revoked and downgraded to minor planet.
Subscribe to:
Posts (Atom)