For those of you who haven't heard about MIT's recent decision to host almost all of their class lessons online I am glad that you have stumbled upon this page. What MIT is doing is simply incredible. They now have over 1500 courses available online for free and they don't even require a registration. Most of the courses have notes, videos, quizzes and tests (plus answers), suggested or required readings, and assignments. MIT OpenCourseWare (OCW) is meant to be used by those who are currently studying material or who wish to remain up to date in their respective fields. But most commonly it is used by self-learners. So whatever category you fit into I highly recommend that you bookmark this site immediately. This is MIT's gift to the world, let's take advantage of it!
Check it out right now! MIT OpenCourseWare
For more information check out their FAQ's.
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Friday, July 20, 2007
Sunday, July 15, 2007
Colonization of Titan-- The Future Persian Gulf?
(Note: this is a continuation of the The Space Colonization Series)
In terms of potential locations in the outer solar system, Saturn's moon Titan is usually mentioned right off the bat. It is a prime location for human survival in the outer regions because of its great abundance of all the necessary organic materials. The atmosphere contains large amounts of methane and nitrogen and it is believed that both liquid water and liquid ammonia are locked under the surface and occasionally pushed out through volcanic activity. Water and methane could be used as both propellants for a rocket and for a colony's power supply. Nitrogen, methane, and ammonia could be used as a source of fertilizer for growing food. The water could also obviously be used for drinking and for oxygen.
Now, looking in an even more speculative nature, Titan would be a major target for a future fusion based economy. We will soon run out of oil on Earth and we will inevitably need to find another source of power. If we ever make a break through on fusion power we know we will need two things that aren't readily available on Earth: helium-3 and deuterium. Saturn has a relatively high amount of these resources available and Titan would be an ideal spot to mine and collect from.
True color image of Titan Surface taken by Huygens. More information from NASA.
Titan is cold. Really, really cold. The temperature is about -180 degrees Celsius. This type of cold also isn't quite as easy to deal with as the cold we would encounter in space or on the Moon. No, Titan's thick atmosphere makes this very difficult. Thermo-insulation becomes a much bigger problem. Fortunately, this problem could potentially be solved be building a protective layer around a habitat. By evacuating a space in between an outer shell and the inner habitat heat loss could be lowered to a more manageable level akin to a lunar habitat's requirements for thermal insulation.
The thick atmosphere does provide some advantages, however. At about 1.47 times the atmospheric pressure of Earth--equivalent to 5 meters under water on Earth--the atmosphere would protect inhabitants from potentially deadly doses of radiation that would be of concern on outposts on Mars, the Moon, or the asteroids. The quality of Titan's atmosphere also greatly decreases the engineering complexity of any aerobraking and landing techniques.
At least one more advantage exists for its atmosphere when combined with Titan's relatively low gravity of 0.14 g's. This unique combination makes flying much easier. So much easier, in fact, that a human could simply strap on some wings and take flight (with a pressurized suit on of course). Other than for human enjoyment and recreation, easier flight requirements could be taken advantage of for more near-term, exploratory missions like sending probes that float around the atmosphere in blimps, hot air balloons, or autonomous planes. Alas, like the atmosphere of Titan, the low gravity also has its disadvantages. Namely the health problems associated with low-g environments.
Personally, I believe Titan will never be more than a mining or research outpost but who knows? Perhaps it could some day be terraformed and become a bastion for thousands or even millions of colonists in the future. It does, after all, contain an abundant amount of the necessary organic materials needed for life as we know it. What do you think? Could you see Titan in our future?
Related Articles:
In terms of potential locations in the outer solar system, Saturn's moon Titan is usually mentioned right off the bat. It is a prime location for human survival in the outer regions because of its great abundance of all the necessary organic materials. The atmosphere contains large amounts of methane and nitrogen and it is believed that both liquid water and liquid ammonia are locked under the surface and occasionally pushed out through volcanic activity. Water and methane could be used as both propellants for a rocket and for a colony's power supply. Nitrogen, methane, and ammonia could be used as a source of fertilizer for growing food. The water could also obviously be used for drinking and for oxygen.
Now, looking in an even more speculative nature, Titan would be a major target for a future fusion based economy. We will soon run out of oil on Earth and we will inevitably need to find another source of power. If we ever make a break through on fusion power we know we will need two things that aren't readily available on Earth: helium-3 and deuterium. Saturn has a relatively high amount of these resources available and Titan would be an ideal spot to mine and collect from.
The Cold, Hard Facts
True color image of Titan Surface taken by Huygens. More information from NASA.
Titan is cold. Really, really cold. The temperature is about -180 degrees Celsius. This type of cold also isn't quite as easy to deal with as the cold we would encounter in space or on the Moon. No, Titan's thick atmosphere makes this very difficult. Thermo-insulation becomes a much bigger problem. Fortunately, this problem could potentially be solved be building a protective layer around a habitat. By evacuating a space in between an outer shell and the inner habitat heat loss could be lowered to a more manageable level akin to a lunar habitat's requirements for thermal insulation.
The thick atmosphere does provide some advantages, however. At about 1.47 times the atmospheric pressure of Earth--equivalent to 5 meters under water on Earth--the atmosphere would protect inhabitants from potentially deadly doses of radiation that would be of concern on outposts on Mars, the Moon, or the asteroids. The quality of Titan's atmosphere also greatly decreases the engineering complexity of any aerobraking and landing techniques.
At least one more advantage exists for its atmosphere when combined with Titan's relatively low gravity of 0.14 g's. This unique combination makes flying much easier. So much easier, in fact, that a human could simply strap on some wings and take flight (with a pressurized suit on of course). Other than for human enjoyment and recreation, easier flight requirements could be taken advantage of for more near-term, exploratory missions like sending probes that float around the atmosphere in blimps, hot air balloons, or autonomous planes. Alas, like the atmosphere of Titan, the low gravity also has its disadvantages. Namely the health problems associated with low-g environments.
Personally, I believe Titan will never be more than a mining or research outpost but who knows? Perhaps it could some day be terraformed and become a bastion for thousands or even millions of colonists in the future. It does, after all, contain an abundant amount of the necessary organic materials needed for life as we know it. What do you think? Could you see Titan in our future?
Related Articles:
- Colonizing Mercury
- The Space Colonization Series
- The Manifest Destiny: Mark II (Essay on our destiny as humans to colonize space)
- Lunar Dirt Factories? A look at how lunar regolith could be the key to permanent outposts on the Moon!
- Why Mine the Asteroid Belt?
- A Floating City on Venus
- About This Blog--My Purpose
Thursday, July 5, 2007
Great Space Quotes
"The earth is the cradle of humankind, but one cannot live in the cradle forever."
This is the quote that I keep at the top of every page on my Space Monitor blog. Konstantin Tsiolkovsky's words provide perhaps the best, most succinct way of describing my purpose for writing this blog. There are many other great quotes out there, though many not quite as short as Tsiolkovsky's, and I would like to share with you all a list of some of my favorite. I encourage any readers out there to submit any of their favorite quotes or perhaps one of their own and I will gladly add them to this list. In the meantime I hope you enjoy the ones I have provided for you.
Here's my list:
"The earth is the cradle of humankind, but one cannot live in the cradle forever."
—Konstantin Tsiolkovsky
"Don't tell me that man doesn't belong out there. Man belongs wherever he wants to go - and he'll do plenty well when he gets there."
— Dr. Wernher von Braun, in 'Time' magazine, 17 February 1958
"Earth is too small a basket for mankind to keep all its eggs in.
— Robert A. Heinlein
"Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring--not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive... If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds."
— Carl Sagan, Pale Blue Dot, 1994
"I don't think the human race will survive the next thousand years, unless we spread into space. There are too many accidents that can befall life on a single planet. But I'm an optimist. We will reach out to the stars."
— Stephen Hawking, interview with Daily Telegraph, 2001
"The dinosaurs became extinct because they didn't have a space program. And if we become extinct because we don't have a space program, it'll serve us right!"
— Larry Nevin
"Remember this: once the human race is established on more than one planet and especially, in more than one solar system, there is no way now imaginable to kill off the human race."
— Robert A. Heinlein
"People who view industrialization as a source of the Earth's troubles, its pollution, and the desecration of its surface, can only advocate that we give it up. This is something that we can't do; we have the tiger by the tail. We have 4.5 billion people on Earth. We can't support that many unless we're industrialized and technologically advanced. So, the idea is not to get rid of industrialization but to move it somewhere else. If we can move it a few thousand miles into space, we still have it, but not on Earth. Earth can then become a world of parks, farms, and wilderness without giving up the benefits of industrialization."
— Isaac Asimov, speech at Rutgers University
"As I stand out here in the wonders of the unknown at Hadley, I sort of realize there's a fundamental truth to our nature, Man must explore . . . and this is exploration at its greatest."
— Dave Scott, Commander Apollo 15, upon becoming the 7th man to walk on the Moon, 31 July 1971.
— Yuri Gagarin
— President John F. Kennedy
"It's human nature to stretch, to go, to see, to understand. Exploration is not a choice, really; it's an imperative."
— Michael Collins
— Stephen Hawking
— Mike Griffin, NASA administrator, Congressional testimony 2004
This is the quote that I keep at the top of every page on my Space Monitor blog. Konstantin Tsiolkovsky's words provide perhaps the best, most succinct way of describing my purpose for writing this blog. There are many other great quotes out there, though many not quite as short as Tsiolkovsky's, and I would like to share with you all a list of some of my favorite. I encourage any readers out there to submit any of their favorite quotes or perhaps one of their own and I will gladly add them to this list. In the meantime I hope you enjoy the ones I have provided for you.
Here's my list:
"The earth is the cradle of humankind, but one cannot live in the cradle forever."
—Konstantin Tsiolkovsky
"Don't tell me that man doesn't belong out there. Man belongs wherever he wants to go - and he'll do plenty well when he gets there."
— Dr. Wernher von Braun, in 'Time' magazine, 17 February 1958
"Earth is too small a basket for mankind to keep all its eggs in.
— Robert A. Heinlein
"Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring--not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive... If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds."
— Carl Sagan, Pale Blue Dot, 1994
"I don't think the human race will survive the next thousand years, unless we spread into space. There are too many accidents that can befall life on a single planet. But I'm an optimist. We will reach out to the stars."
— Stephen Hawking, interview with Daily Telegraph, 2001
"The dinosaurs became extinct because they didn't have a space program. And if we become extinct because we don't have a space program, it'll serve us right!"
— Larry Nevin
"Remember this: once the human race is established on more than one planet and especially, in more than one solar system, there is no way now imaginable to kill off the human race."
— Robert A. Heinlein
"People who view industrialization as a source of the Earth's troubles, its pollution, and the desecration of its surface, can only advocate that we give it up. This is something that we can't do; we have the tiger by the tail. We have 4.5 billion people on Earth. We can't support that many unless we're industrialized and technologically advanced. So, the idea is not to get rid of industrialization but to move it somewhere else. If we can move it a few thousand miles into space, we still have it, but not on Earth. Earth can then become a world of parks, farms, and wilderness without giving up the benefits of industrialization."
— Isaac Asimov, speech at Rutgers University
"As I stand out here in the wonders of the unknown at Hadley, I sort of realize there's a fundamental truth to our nature, Man must explore . . . and this is exploration at its greatest."
— Dave Scott, Commander Apollo 15, upon becoming the 7th man to walk on the Moon, 31 July 1971.
"It [the rocket] will free man from his remaining chains, the chains of gravity which still tie him to this planet. It will open to him the gates of heaven."
— Wernher von Braun
"God has no intention of setting a limit to the efforts of man to conquer space."
— Pope Pius XII
— Yuri Gagarin
"Astronomy compels the soul to look upward, and leads us from this world to another."
— Plato, 'The Republic,' 342 B.C.
"... the United States was not built by those who waited and rested and wished to look behind them. This country was conquered by those who moved forward, and so will space."
— President John F. Kennedy
— President John F. Kennedy
"It's human nature to stretch, to go, to see, to understand. Exploration is not a choice, really; it's an imperative."
— Michael Collins
"To go places and do things that have never been done before - that's what living is all about."
— Michael Collins
— Stephen Hawking
"When you look at the stars and the galaxy, you feel you are not just from any particular piece of land, but from the solar system."
— Laurel Clark
"It's time for the human race to enter the solar system."
— Dan Quayle
— Mike Griffin, NASA administrator, Congressional testimony 2004
"The regret on our side is, they used to say years ago, we are reading about you in science class. Now they say, we are reading about you in history class."
— Neil Armstrong, July 1999
"Many say exploration is part of our destiny, but it's actually our duty to future generations and their quest to ensure the survival of the human species."
— Buzz Aldrin, on the 37th Anniversary of the Apollo 11 Landing, July 2006
Reader Submissions:
"Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe."
— Albert Einstein
Related Articles:
- Receive an MIT education for FREE!
- The Space Colonization Series
- The Manifest Destiny: Mark II (Essay on our destiny as humans to colonize space)
- Absolutely Awesome Images of Space
- Recommended Space Blogs
- The Top 10 Things to Experience in A Space Hotel
- Summer Williams:The best cheerleader for space--Literally
- About This Blog--My Purpose
Tuesday, July 3, 2007
Colonizing Mercury
(Note: this is a continuation of the The Space Colonization Series)
I'll be honest; a colony on Mercury is out there--waaay out there. Many would naturally assume that Mercury could never be colonized or that even if we could it would be highly impractical. Right now I would most definitely agree with that statement but, in the future, as we expand our horizons and colonize our solar system that first rock from the sun may prove to be one of the key locations for supporting a space-fairing civilization.
What Does Mercury Have to Offer?
Image of Mercury orbiting around the Sun. Source: NASA.gov
Quite a few benefits actually. One of the biggest is solar energy. The close proximity to the sun could allow for Mercury to be a potential location for harvesting solar energy. The solar constant near Mercury is 9.13 kW/m² or 6.5 times that of the Earth or Moon. Now, with this extra energy it would be possible to power mass drivers (similar to a maglev launch system) and launch folded up solar sails carrying any sort of cargo or mined resources from the planet. Once deployed into space and unfolded, the solar sail would receive an added boost from the stronger solar constant--6.5 times the thrust to be specific. Mercury could also be used as the starting point for either interstellar travel or simply travel into the outer solar system using the added solar boost to speed the process along.
Launching mined materials from the planet could prove to be lucratively advantageous considering the composition of it. Mercury is the second most dense planet (behind Earth). As a result it indicates that anywhere from 60-70% (by weight) of the planet is composed of metals with the rest primarily being silicate. In addition, it is theorized that Mercury may have some of the highest concentrations of several valuable minerals and metals of any surface in our solar system and in extremely concentrated ores on top of that. Other predictions include the possibility of the soil containing a large quantity of helium-3--an essential ingredient in a future fusion power plant.
Lastly, due to Mercury's prime location near the Sun, it could provide an excellent site for monitoring solar activity. A base could warn any traveling ships, other various colonies, or even Earth that a solar flare is approaching or a burst of solar radiation could make a certain area dangerous for the time being. A constant close-up watch of the Sun would definitely help us learn more about it and perhaps allow us to forecast any solar activity. Learning more about the Sun is definitely important and Mercury is the closest place to it.
How Could it be Done?
Colonizing and creating the necessary infrastructure would likely be both very difficult and very dangerous. This is not to say that it can't be done though. Long days (176 Earth days), no real atmosphere, and a lack of organic materials/elements requiring importation make it difficult but not impossible. This is because of the relatively static climate of the polar regions. It would avoid the extreme variations of temperature that are hot enough to melt lead during the daytime and the nighttime bone-chilling lows of -180 degrees Celsius. In fact, the polar regions may also harbor the ever essential water-ice in permanently shaded regions inside craters.
Magnetic field of Mercury. Source: NASA.gov
Mercury even limits a couple of other major, ubiquitous problems involved in space exploration and colonization. Perhaps its most important advantage towards allowing for a habitat is its magnetic field. Though only about 1% of the strength of Earth's own magnetic field, Mercury's field deflects solar wind about 1000 km from the surface and this may be more than enough protection for colonists. The strength of Mercury's gravity is also another asset that places like the Moon or asteroids can't provide. At about .377 g's, Mercury has twice the gravity of the Moon and approximately equal to that of Mars. This is especially important because some scientists believe that .33 g's is all that is necessary to be acceptable to the human body over an extended period.
As a colony establishes itself the non-polar regions of the planet may end up providing more room for habitats and mining operations. Underground bases could potentially insulate itself from the extreme temperatures on the surface above. Traveling outside of the underground base could easily be accomplished during times of twilight. Due to the planet's very slow rotational period the window of time for exiting or exploring the surface would also likely be significant.
In the end I do believe that the colonization of Mercury is inevitable. Whether it is used to support some lucrative mining operation, outsource power, be the starting point of journeys to the outer solar system and beyond, manufacture anti-matter with fusion reactors, as a futuristic Alcatraz/Australia, or some combination of all them, it definitely holds a future and purpose for mankind. How long that is before it is I can't answer you but, regardless, it's still fun to imagine it. Personally, I think it would just be fun to watch a giant sun rise above the horizon during the Mercurian morning. What do you guys think?
Related Articles:
I'll be honest; a colony on Mercury is out there--waaay out there. Many would naturally assume that Mercury could never be colonized or that even if we could it would be highly impractical. Right now I would most definitely agree with that statement but, in the future, as we expand our horizons and colonize our solar system that first rock from the sun may prove to be one of the key locations for supporting a space-fairing civilization.
What Does Mercury Have to Offer?
Image of Mercury orbiting around the Sun. Source: NASA.gov
Quite a few benefits actually. One of the biggest is solar energy. The close proximity to the sun could allow for Mercury to be a potential location for harvesting solar energy. The solar constant near Mercury is 9.13 kW/m² or 6.5 times that of the Earth or Moon. Now, with this extra energy it would be possible to power mass drivers (similar to a maglev launch system) and launch folded up solar sails carrying any sort of cargo or mined resources from the planet. Once deployed into space and unfolded, the solar sail would receive an added boost from the stronger solar constant--6.5 times the thrust to be specific. Mercury could also be used as the starting point for either interstellar travel or simply travel into the outer solar system using the added solar boost to speed the process along.Launching mined materials from the planet could prove to be lucratively advantageous considering the composition of it. Mercury is the second most dense planet (behind Earth). As a result it indicates that anywhere from 60-70% (by weight) of the planet is composed of metals with the rest primarily being silicate. In addition, it is theorized that Mercury may have some of the highest concentrations of several valuable minerals and metals of any surface in our solar system and in extremely concentrated ores on top of that. Other predictions include the possibility of the soil containing a large quantity of helium-3--an essential ingredient in a future fusion power plant.
Lastly, due to Mercury's prime location near the Sun, it could provide an excellent site for monitoring solar activity. A base could warn any traveling ships, other various colonies, or even Earth that a solar flare is approaching or a burst of solar radiation could make a certain area dangerous for the time being. A constant close-up watch of the Sun would definitely help us learn more about it and perhaps allow us to forecast any solar activity. Learning more about the Sun is definitely important and Mercury is the closest place to it.
How Could it be Done?
Colonizing and creating the necessary infrastructure would likely be both very difficult and very dangerous. This is not to say that it can't be done though. Long days (176 Earth days), no real atmosphere, and a lack of organic materials/elements requiring importation make it difficult but not impossible. This is because of the relatively static climate of the polar regions. It would avoid the extreme variations of temperature that are hot enough to melt lead during the daytime and the nighttime bone-chilling lows of -180 degrees Celsius. In fact, the polar regions may also harbor the ever essential water-ice in permanently shaded regions inside craters.
Magnetic field of Mercury. Source: NASA.gov
Mercury even limits a couple of other major, ubiquitous problems involved in space exploration and colonization. Perhaps its most important advantage towards allowing for a habitat is its magnetic field. Though only about 1% of the strength of Earth's own magnetic field, Mercury's field deflects solar wind about 1000 km from the surface and this may be more than enough protection for colonists. The strength of Mercury's gravity is also another asset that places like the Moon or asteroids can't provide. At about .377 g's, Mercury has twice the gravity of the Moon and approximately equal to that of Mars. This is especially important because some scientists believe that .33 g's is all that is necessary to be acceptable to the human body over an extended period.As a colony establishes itself the non-polar regions of the planet may end up providing more room for habitats and mining operations. Underground bases could potentially insulate itself from the extreme temperatures on the surface above. Traveling outside of the underground base could easily be accomplished during times of twilight. Due to the planet's very slow rotational period the window of time for exiting or exploring the surface would also likely be significant.
In the end I do believe that the colonization of Mercury is inevitable. Whether it is used to support some lucrative mining operation, outsource power, be the starting point of journeys to the outer solar system and beyond, manufacture anti-matter with fusion reactors, as a futuristic Alcatraz/Australia, or some combination of all them, it definitely holds a future and purpose for mankind. How long that is before it is I can't answer you but, regardless, it's still fun to imagine it. Personally, I think it would just be fun to watch a giant sun rise above the horizon during the Mercurian morning. What do you guys think?
Related Articles:
- Colonization of Titan-- The Future Persian Gulf?
- The Space Colonization Series
- The Manifest Destiny: Mark II (Essay on our destiny as humans to colonize space)
- Lunar Dirt Factories? (A look at how lunar regolith could help us colonize the Moon)
- A Floating City on Venus
- Magnetic Launch System
- About This Blog--My Purpose
Sunday, July 1, 2007
The Space Colonization Series
UPDATE 1 (July 15, 2007):. Four articles have now been completed with Titan being the most recent.
UPDATE 2 (July 15, 2007): from the suggestion from a reader I have decided to add a Space Habitat on my to do list. I plan on this one being one of the most extensive if not the most extensive article that I write on space colonization.
Having already completed articles on ways to colonize Venus and the Moon and also having already received a suggestion for writing about colonizing Mercury, I have decided to do an entire 'Colonization Series.' I plan on writing articles about five or six more potential sites for colonization (including Mercury). I may also eventually write an editorial covering humankind's reason to colonize space. So, I hope I give you all something to look forward to!
Here is the complete list of colonization options I plan on writing about (completed articles are linked in blue):
Also, if anyone has any suggestions or would like to see an article on perhaps another potential location for colonization I encourage you to speak up. Or, just anything space related that you believe would be appropriate/interesting.
Related Articles:
UPDATE 2 (July 15, 2007): from the suggestion from a reader I have decided to add a Space Habitat on my to do list. I plan on this one being one of the most extensive if not the most extensive article that I write on space colonization.
Having already completed articles on ways to colonize Venus and the Moon and also having already received a suggestion for writing about colonizing Mercury, I have decided to do an entire 'Colonization Series.' I plan on writing articles about five or six more potential sites for colonization (including Mercury). I may also eventually write an editorial covering humankind's reason to colonize space. So, I hope I give you all something to look forward to!
Here is the complete list of colonization options I plan on writing about (completed articles are linked in blue):
Also, if anyone has any suggestions or would like to see an article on perhaps another potential location for colonization I encourage you to speak up. Or, just anything space related that you believe would be appropriate/interesting.
Related Articles:
- The Manifest Destiny: Mark II (Essay on our destiny as humans to colonize space)
- About This Blog--My Purpose