Monday, June 18, 2007
Et In Circadia Ego
Mammals evolved on a planet with a day that is 24 hours long, or thereabouts. So it should come as no surprise that genes are finely tuned to Earth's daily cycle.
Mars has a day that is about 40 minutes longer than 24 hours. Some JPL Rover scientists and engineers lived on Mars time early in the mission and the experiment played havoc with their lives. Some of that can be attributed to what was, in essence, trying to live on two planets at once. (Here.) But other research has shown that living non-Earth standard days harms human health and productivity and leads to "jet lag in space." (Here.)
Research by Brigham and Women’s Hospital’s (BWH) Division of Sleep Medicine has shown that humans can function in a longer day by resetting their circadian rhythms through modulation of the brightness of artificial light over the course of a day. (Here.) But the purpose of the BWH research was to find measures that would allow humans to work effectively in a non-Earth standard day on missions with a defined length.
How will humans cope with living non-standard days for their entire lives? And if every single life function down to the genetic level is tuned to Earth's 24-hour daily rhythm, how will humanity change once new generations are born and die off-Earth?
-tdr
Technorati:
NASA, 
space, 
mars, 
science.
"New research from Colorado State University shows that the function of all genes in mammals is based on circadian -- or daily -- rhythms. The study, refutes the current theory that only 10 percent to 15 percent of all genes were affected by nature's clock. While scientists have long known that circadian rhythms regulate the behavior of the living, the study shows that daily rhythm dominates all life functions and particularly metabolism." (Here.)The fact that the Earth's 24-hour "daily rhythm dominates all life functions" has got to have implications for long-term human settlement of other planets in our Solar System.
Mars has a day that is about 40 minutes longer than 24 hours. Some JPL Rover scientists and engineers lived on Mars time early in the mission and the experiment played havoc with their lives. Some of that can be attributed to what was, in essence, trying to live on two planets at once. (Here.) But other research has shown that living non-Earth standard days harms human health and productivity and leads to "jet lag in space." (Here.)
Research by Brigham and Women’s Hospital’s (BWH) Division of Sleep Medicine has shown that humans can function in a longer day by resetting their circadian rhythms through modulation of the brightness of artificial light over the course of a day. (Here.) But the purpose of the BWH research was to find measures that would allow humans to work effectively in a non-Earth standard day on missions with a defined length.
How will humans cope with living non-standard days for their entire lives? And if every single life function down to the genetic level is tuned to Earth's 24-hour daily rhythm, how will humanity change once new generations are born and die off-Earth?
-tdr
Technorati:
NASA, space, mars, science.Labels: Health, Manifest Destiny, Mars
Monday, April 24, 2006
Red Sky At Morning, Spacers Take Warning?
It's been said that every historical analogy is a lie. While such analogies can be misleading there are lessons to be learned from history. One of those lessons involves colonization or settlement of new worlds.
The American colonies after Columbus evolved differently. The key to the differences seems to depend on who was the mother country. The American colonies of Britain evolved into prosperous and free democracies. The American colonies of Spain have a long history of authoritarian government and poverty.
Today there are three countries with manned space programs: The US, China, and Russia. Among the three China's movement into space has generated no small amount of controversy between those who are concerned about China's ambitions in space and those who are more sanguine.
Transterrestrial Musings scores a point on the sanguine side with a comment on China's very slow pace of human spaceflights. (Here.) China's capabilities in space clearly have not yet matured much. The program is hardly a threat in the near term. China's government is a threat, however, and in the longer term, is it really a good thing that China is extending her influence into space?
As with all our futures, China's future is unknown. Since space settlement is not a near-term endeavor, whether China will be a positive or negative force in space is unknown and unknowable. What we know of China's past is that it swings back and forth between unity and disunity, and that its political culture has a long history of authoritarian rule.
What we know of China's present is not reassuring. China remains a communist country with a government that oppresses its people. That government relies more and more on nationalism to hold the country together, it is making strategic moves around the world to expand its political and military influence, and, although not technically an enemy of the United States, it is a "strategic rival." On the other hand, authoritarianism need not be a characteristic of Chinese society; Taiwan has a strong democracy alongside a healthy economy.
So, who knows? Maybe China will be democratic by the time humans get around to settling the Solar System. Maybe China will have fallen into another of its periods of disunity by then. Or maybe China will remain united, nationalistic, and unfree at the time.
The historical lesson for space settlement from America's colonization is obvious. It makes a difference to future space settlers who is the mother country. That's the most important reason why the US, still free so far and with its history of freedom, should remain a leader in space exploration. It's also why it's not necessarily a good thing that a presently and historically unfree China has a manned space program.
-tdr
Technorati: Space, Space Exploration, NASA, China.
The American colonies after Columbus evolved differently. The key to the differences seems to depend on who was the mother country. The American colonies of Britain evolved into prosperous and free democracies. The American colonies of Spain have a long history of authoritarian government and poverty.
Today there are three countries with manned space programs: The US, China, and Russia. Among the three China's movement into space has generated no small amount of controversy between those who are concerned about China's ambitions in space and those who are more sanguine.
Transterrestrial Musings scores a point on the sanguine side with a comment on China's very slow pace of human spaceflights. (Here.) China's capabilities in space clearly have not yet matured much. The program is hardly a threat in the near term. China's government is a threat, however, and in the longer term, is it really a good thing that China is extending her influence into space?
As with all our futures, China's future is unknown. Since space settlement is not a near-term endeavor, whether China will be a positive or negative force in space is unknown and unknowable. What we know of China's past is that it swings back and forth between unity and disunity, and that its political culture has a long history of authoritarian rule.
What we know of China's present is not reassuring. China remains a communist country with a government that oppresses its people. That government relies more and more on nationalism to hold the country together, it is making strategic moves around the world to expand its political and military influence, and, although not technically an enemy of the United States, it is a "strategic rival." On the other hand, authoritarianism need not be a characteristic of Chinese society; Taiwan has a strong democracy alongside a healthy economy.
So, who knows? Maybe China will be democratic by the time humans get around to settling the Solar System. Maybe China will have fallen into another of its periods of disunity by then. Or maybe China will remain united, nationalistic, and unfree at the time.
The historical lesson for space settlement from America's colonization is obvious. It makes a difference to future space settlers who is the mother country. That's the most important reason why the US, still free so far and with its history of freedom, should remain a leader in space exploration. It's also why it's not necessarily a good thing that a presently and historically unfree China has a manned space program.
-tdr
Technorati: Space, Space Exploration, NASA, China.
Labels: China, Manifest Destiny
Friday, April 14, 2006
All That Sunlight, All That Energy, All That Power.
Last night in San Diego author David Schrunk (here) spoke about his vision for the next 50 to 100 years of development of the Moon and the inner Solar System. His talk was hosted by professor Phil Blanco at Grossmont College and presented by the Mars Society of San Diego.
Schrunk's vision of the next century sees humans leaving the Earth to use resources in space independent of resources on Earth in order to inaugurate a spacefaring age. Schrunk contrasted the Industrial Age to the future Spacefaring Age. What made the Industrial Age was the "linking of human expertise to limited resources" of a single planet. The Spacefaring Age will "link human expertise to unlimited resources" of our Solar System.
The logical first step for Schrunk is the Moon, which he described as an "oasis in space that will protect humans from the hazards of space." Using the Moon's abundant mineral resources, humans will start a new industrial age in space based on non-terrestrial resources.
The Moon is short on water but long on energy. Solar energy bombards the Moon unfiltered by an atmosphere. Lunar regolith is abundant in the materials necessary to build solar power cells. In Schrunk's vision of the future, the Moon could become the energy producer for our entire civilization if we were to ring the circumference of Luna with solar cells and transmit the energy created there to the Earth using microwaves.
He proposes that Lunar development start near the South Pole on Malapert Summit, a five kilometer high peak that is in sunlight for 90 percent of the time and is always in a straight line view of the Earth. Over time, development could expand around the polar circumference with solar power stations and manufacturing facilities linked together by a railroad or maglev system. More dramatic transportation off Malapert could be achieved by a cable car that would descend from the peak to the floor of a crater eight kilometers below.
He says that we would live underground on the Moon for protection from radiation, micrometeorites, and the temperature extremes on the surface. For instance, one meter under the Lunar surface the temperature is a constant -20C. Not very warm but better than the extremes on the surface that can range from 130C down to -110C.
In Schrunk's vision, humans would use all the resources the Moon has to offer and recycle, recycle, recycle. Even Lunar dust, or especially Lunar dust, which is nearly everywhere and could be a health and mechanical hazard for human colonization with its sharp edges and tiny size would be treated as an asset. Future colonists could produce water out of the hydrogen found in the dust and the oxygen found in Lunar rocks.
His vision for the Inner Solar System relies heavily on the most abundant resource available within the orbit of Mars: solar energy. He envisions power stations on Mercury with a Solar Sail hovering over a pole to transmit energy elsewhere. He also suggested that extremely large Solar Sails could be placed in the L1 orbital position between Venus and the Sun to cool down the atmosphere of our overheated sister planet. At Mars, Solar Sails could hover around the planet and transmit energy down to bases on the surface. Near Earth Asteroids could be mined for their minerals as well.
He also envisions using the abundant solar energy available in the Inner Solar System to power an interplanetary transportation system. For example a sail-driven spaceship could fly from the Moon pushed by Lunar lasers powered by the Sun. Around Mars solar powered lasers could take over and slow the ship down.
After Schrunk spoke, the Mars Society's Gerry Williams told the audience about some people who are working here and now on Earth to make human development of the Moon a reality. Williams described a recent two week simulated Lunar mission in the Utah desert in which members of the Moon Society took over the Mars Society's research station. (Read more about Crew 45 and view photographs here.)
Nobody can tell now how long it will take until Schrunk's vision, or something like it, becomes a reality. But someday motivated people with the talent, the money, and the ambition, will make it so.
-tdr
Technorati: space, Moon, Science, solar power, Astronomy.
Schrunk's vision of the next century sees humans leaving the Earth to use resources in space independent of resources on Earth in order to inaugurate a spacefaring age. Schrunk contrasted the Industrial Age to the future Spacefaring Age. What made the Industrial Age was the "linking of human expertise to limited resources" of a single planet. The Spacefaring Age will "link human expertise to unlimited resources" of our Solar System.
The logical first step for Schrunk is the Moon, which he described as an "oasis in space that will protect humans from the hazards of space." Using the Moon's abundant mineral resources, humans will start a new industrial age in space based on non-terrestrial resources.
The Moon is short on water but long on energy. Solar energy bombards the Moon unfiltered by an atmosphere. Lunar regolith is abundant in the materials necessary to build solar power cells. In Schrunk's vision of the future, the Moon could become the energy producer for our entire civilization if we were to ring the circumference of Luna with solar cells and transmit the energy created there to the Earth using microwaves.
He proposes that Lunar development start near the South Pole on Malapert Summit, a five kilometer high peak that is in sunlight for 90 percent of the time and is always in a straight line view of the Earth. Over time, development could expand around the polar circumference with solar power stations and manufacturing facilities linked together by a railroad or maglev system. More dramatic transportation off Malapert could be achieved by a cable car that would descend from the peak to the floor of a crater eight kilometers below.
He says that we would live underground on the Moon for protection from radiation, micrometeorites, and the temperature extremes on the surface. For instance, one meter under the Lunar surface the temperature is a constant -20C. Not very warm but better than the extremes on the surface that can range from 130C down to -110C.
In Schrunk's vision, humans would use all the resources the Moon has to offer and recycle, recycle, recycle. Even Lunar dust, or especially Lunar dust, which is nearly everywhere and could be a health and mechanical hazard for human colonization with its sharp edges and tiny size would be treated as an asset. Future colonists could produce water out of the hydrogen found in the dust and the oxygen found in Lunar rocks.
His vision for the Inner Solar System relies heavily on the most abundant resource available within the orbit of Mars: solar energy. He envisions power stations on Mercury with a Solar Sail hovering over a pole to transmit energy elsewhere. He also suggested that extremely large Solar Sails could be placed in the L1 orbital position between Venus and the Sun to cool down the atmosphere of our overheated sister planet. At Mars, Solar Sails could hover around the planet and transmit energy down to bases on the surface. Near Earth Asteroids could be mined for their minerals as well.
He also envisions using the abundant solar energy available in the Inner Solar System to power an interplanetary transportation system. For example a sail-driven spaceship could fly from the Moon pushed by Lunar lasers powered by the Sun. Around Mars solar powered lasers could take over and slow the ship down.
After Schrunk spoke, the Mars Society's Gerry Williams told the audience about some people who are working here and now on Earth to make human development of the Moon a reality. Williams described a recent two week simulated Lunar mission in the Utah desert in which members of the Moon Society took over the Mars Society's research station. (Read more about Crew 45 and view photographs here.)
Nobody can tell now how long it will take until Schrunk's vision, or something like it, becomes a reality. But someday motivated people with the talent, the money, and the ambition, will make it so.
-tdr
Technorati: space, Moon, Science, solar power, Astronomy.
Labels: Manifest Destiny
Tuesday, February 28, 2006
The Lifeboat Theory Of Space Settlement And The Tragedy Of Human Nature.
Spacedaily has this story about Astrobiology magazine's publication of their latest thought experiment. (Here.) In this one, scientist Bernard Foing proposes putting a "Noah's Ark" on the Moon to preserve humanity and life as we know it in the event disaster befalls the Earth.
The lifeboat theory of space settlement is a fairly common justification for human colonization of other planets. That theory holds that other worlds could be a refuge for humanity in the event the Earth is destroyed by war or environmental destruction or a big giant asteroid or comet striking our world.
Not a bad idea but you've got to wonder how practical it is. If it's war that destroys the Earth the conflict is likely to sweep the colonies in space. As a refuge in case of environmental disaster, well that's a better idea, although if we can't save our own planet from ecological catastrophe, one wonders how we'll do making other planets habitable for humanity.
But as havens against asteroid or comet collision, Earth is at least as safe as anywhere else. With apologies to the followers of Gerard K. O'Neill, the two most commonly suggested homes for humanity in space are the Moon and Mars. The common characteristic of those two worlds is how heavily cratered they are.
Unlike the Moon, the Earth has an atmosphere to protect it from collisions. It's true that Earth's atmosphere won't protect us from a large asteroid but there is even less protection on the Moon. On the Moon, even the tiniest of meteors has a clear shot at the surface because of the lack of a true Lunar atmosphere.
As for Mars, one look at all the craters tells the story about that planet's history with asteroid collisions. Its two moons are asteroids for that matter. And just look at its location in the Solar System: one orbital position in from the Asteroid Belt.
We've always been a bit depressed at the lifeboat theory of space settlement. We prefer more glorious reasons for settling space. Spreading life to other planets, preparing other worlds for new branches of human civilization, opening frontiers, fulfilling American manifest destiny --- humanity's too, and making tons of money. O yeah, and learning things about the universe we live in. That's also important. But settling other planets so we can preserve humans in case Earth is destroyed; that's just depressing.
On the other hand, we have to admit that humans are a sorry lot who, although they learn from their mistakes, can really make a mess of things before they get it right. We also have to admit that we subscribe to a tragic view of humanity in which human nature is fixed throughout time and in which the future is likely to see the same sort of problems as the past and the present, just played out in different ways and magnified, thanks to how advanced our science and technology have become. In other words, with humans, what you see is what you get, and the best we can hope for is to preserve civilization to keep our worst instincts in check.
So, by all means lets put lifeboats on other planets. Humanity will certainly be better off when we spread our eggs among many baskets. Yet one could describe space settlement as the easy way out. The hard way would be learning to get along with each other, learning how our ecology can be protected, tracking the solar bodies that can do our planet in, and learning how to divert or destroy them before they do. Given human nature, however, our best bet for long-term survival is to do settlement and the rest. There's no good reason why we shouldn't.
-tdr
Technorati:
space
Mars
Moon
science
The lifeboat theory of space settlement is a fairly common justification for human colonization of other planets. That theory holds that other worlds could be a refuge for humanity in the event the Earth is destroyed by war or environmental destruction or a big giant asteroid or comet striking our world.
Not a bad idea but you've got to wonder how practical it is. If it's war that destroys the Earth the conflict is likely to sweep the colonies in space. As a refuge in case of environmental disaster, well that's a better idea, although if we can't save our own planet from ecological catastrophe, one wonders how we'll do making other planets habitable for humanity.
But as havens against asteroid or comet collision, Earth is at least as safe as anywhere else. With apologies to the followers of Gerard K. O'Neill, the two most commonly suggested homes for humanity in space are the Moon and Mars. The common characteristic of those two worlds is how heavily cratered they are.
Unlike the Moon, the Earth has an atmosphere to protect it from collisions. It's true that Earth's atmosphere won't protect us from a large asteroid but there is even less protection on the Moon. On the Moon, even the tiniest of meteors has a clear shot at the surface because of the lack of a true Lunar atmosphere.
As for Mars, one look at all the craters tells the story about that planet's history with asteroid collisions. Its two moons are asteroids for that matter. And just look at its location in the Solar System: one orbital position in from the Asteroid Belt.
We've always been a bit depressed at the lifeboat theory of space settlement. We prefer more glorious reasons for settling space. Spreading life to other planets, preparing other worlds for new branches of human civilization, opening frontiers, fulfilling American manifest destiny --- humanity's too, and making tons of money. O yeah, and learning things about the universe we live in. That's also important. But settling other planets so we can preserve humans in case Earth is destroyed; that's just depressing.
On the other hand, we have to admit that humans are a sorry lot who, although they learn from their mistakes, can really make a mess of things before they get it right. We also have to admit that we subscribe to a tragic view of humanity in which human nature is fixed throughout time and in which the future is likely to see the same sort of problems as the past and the present, just played out in different ways and magnified, thanks to how advanced our science and technology have become. In other words, with humans, what you see is what you get, and the best we can hope for is to preserve civilization to keep our worst instincts in check.
So, by all means lets put lifeboats on other planets. Humanity will certainly be better off when we spread our eggs among many baskets. Yet one could describe space settlement as the easy way out. The hard way would be learning to get along with each other, learning how our ecology can be protected, tracking the solar bodies that can do our planet in, and learning how to divert or destroy them before they do. Given human nature, however, our best bet for long-term survival is to do settlement and the rest. There's no good reason why we shouldn't.
-tdr
Technorati:
space
Mars
Moon
science
Labels: Manifest Destiny
Sunday, November 13, 2005
A Record Of Accomplishment Living In Space.
Those who wish humans were spreading through the heliosphere faster than we are have lamented NASA's drive into the cul de sac of lower Earth orbit since the demise of Apollo. Billions and billions of dollars have been spent on flying the outdated Space Shuttle to what many believe is a boondoggle in the sky, the International Space Station. Yet the following tidbit of fact from a newsletter out of MIT suggests that the ISS may not have been a complete waste.
If humans are going to successfully spread into the universe and make a home of it, we are going to need practice living and working in space. For all of the space station's faults, the ISS has provided a home for humans in space. Not the first, there were the Salyuts, Skylab and Mir before the ISS. In fact, humans have lived in lower Earth orbit nearly continuously since 1986 thanks to the Russians.
The Soviet Union launched Mir in March of 1986, and from then until 1999 it was always occupied except for two brief periods: 7 months from July 1986 to February 1987, and May 1989 until September 1989. From September 1989 until August 1999 it was always occupied. Mir's final residents lived there from briefly from April to June 2000. Four months later, the ISS opened its doors to its first residents.
If we count Mir, since March 1986 humans have lived in lower Earth orbit for 212 out of 235 months. That's a mere 23 months in which humans have not lived in space in the past 19 years. That's a pretty good record of accomplishment. Thanks, Ivan! (See this site, here, for more on the history of Russia's accomplishments in space.)
-tdr
"Humans have now been living in space continuously for 5 years! On November 2nd, 2000, Bill Shepherd, Sergei Krikalev, and Yuri Gidzenko took up residence in the International Space Station – and ever since that first expedition, the station has been constantly inhabited. In total, 12 crews have lived and worked in the ISS over the course of the past 5 years, and the station has hosted 97 visitors from 10 countries. Reflecting on this anniversary, Shepherd expressed the hope that knowledge gained onboard will lead to human exploration far beyond low Earth orbit."(MIT's Mars Gravity Biosatellite Program website here.)
If humans are going to successfully spread into the universe and make a home of it, we are going to need practice living and working in space. For all of the space station's faults, the ISS has provided a home for humans in space. Not the first, there were the Salyuts, Skylab and Mir before the ISS. In fact, humans have lived in lower Earth orbit nearly continuously since 1986 thanks to the Russians.
The Soviet Union launched Mir in March of 1986, and from then until 1999 it was always occupied except for two brief periods: 7 months from July 1986 to February 1987, and May 1989 until September 1989. From September 1989 until August 1999 it was always occupied. Mir's final residents lived there from briefly from April to June 2000. Four months later, the ISS opened its doors to its first residents.
If we count Mir, since March 1986 humans have lived in lower Earth orbit for 212 out of 235 months. That's a mere 23 months in which humans have not lived in space in the past 19 years. That's a pretty good record of accomplishment. Thanks, Ivan! (See this site, here, for more on the history of Russia's accomplishments in space.)
-tdr
Labels: Manifest Destiny
Monday, October 24, 2005
Hunting Asteroids For Profit And The Benefit Of All Humankind.
Yesterday we reported on Michael A'Hearn's talk about the Deep Impact mission at the Space Frontier Foundation's annual conference. Today we report on Thomas Matula's (resume here) proposal for private commercial missions to Near Earth Asteroids (NEAs) for profit, and, by the way, to save humanity from the fate of the dinosaurs.
Probably the biggest question facing private space entrepreneurs is how to make money in space. What's the market for space entrepreneurs? The trend for suborbital rocketeers seems to be tourism. Virgin Galactic and others are moving forward with their plans to fly tourists on roller coaster-like flights into space. But beyond sub-orbit what's the market?
To some, a major threat facing humanity is the risk of extinction from a collision by an uncharted asteroid. How do we protect ourselves when we haven't mapped many of the NEAs and we don't know enough about them to deflect or destroy one headed our way, even if we knew it was coming?
Thomas Matula has thought about both these questions and come up with a solution: bounty hunters in the sky.
Matula's proposal would have the United States Congress appropriate money for a program to pay bounties for data about NEAs. The bounties would be open to any company in the United States who would fly a scouting mission to an NEA and send back data about the rock. The program would be modeled after the bounties paid to hunters in the 19th Century American frontier who killed predators of cows and sheep. The government paid bounties for results and only with proof of the kill.
For the NEA program, the federal government would pay a bounty for information about the asteroids. There would be a fixed price for different kinds of data: composition of the asteroid, rotational periods, density, orbits, and so on, up to $40 million total for one asteroid. There would be a 20 percent premium for information about an NEA found to be a hazard to Earth. The bounty would not be paid for sending a mission. It would only be paid upon delivery of the data.
Matula touted several benefits to this program. It likely would have popular support. Matula said that in surveys of public opinion the two most popular reasons given for a space program are obtaining solar energy from space and defending Earth from Near Earth Asteroids. It would be a relatively inexpensive program. It would externalize costs because payment would be contingent on performance. It would create a market for space entrepreneurs that would encourage commercial space missions. It would provide needed information about NEAs that otherwise might not be obtained. And, although he didn't put it this way, it just might save humanity from extinction. With apologies to those who view people as a virus on the face of the Earth, that is perhaps the greatest benefit of them all.
-tdr
Probably the biggest question facing private space entrepreneurs is how to make money in space. What's the market for space entrepreneurs? The trend for suborbital rocketeers seems to be tourism. Virgin Galactic and others are moving forward with their plans to fly tourists on roller coaster-like flights into space. But beyond sub-orbit what's the market?
To some, a major threat facing humanity is the risk of extinction from a collision by an uncharted asteroid. How do we protect ourselves when we haven't mapped many of the NEAs and we don't know enough about them to deflect or destroy one headed our way, even if we knew it was coming?
Thomas Matula has thought about both these questions and come up with a solution: bounty hunters in the sky.
Matula's proposal would have the United States Congress appropriate money for a program to pay bounties for data about NEAs. The bounties would be open to any company in the United States who would fly a scouting mission to an NEA and send back data about the rock. The program would be modeled after the bounties paid to hunters in the 19th Century American frontier who killed predators of cows and sheep. The government paid bounties for results and only with proof of the kill.
For the NEA program, the federal government would pay a bounty for information about the asteroids. There would be a fixed price for different kinds of data: composition of the asteroid, rotational periods, density, orbits, and so on, up to $40 million total for one asteroid. There would be a 20 percent premium for information about an NEA found to be a hazard to Earth. The bounty would not be paid for sending a mission. It would only be paid upon delivery of the data.
Matula touted several benefits to this program. It likely would have popular support. Matula said that in surveys of public opinion the two most popular reasons given for a space program are obtaining solar energy from space and defending Earth from Near Earth Asteroids. It would be a relatively inexpensive program. It would externalize costs because payment would be contingent on performance. It would create a market for space entrepreneurs that would encourage commercial space missions. It would provide needed information about NEAs that otherwise might not be obtained. And, although he didn't put it this way, it just might save humanity from extinction. With apologies to those who view people as a virus on the face of the Earth, that is perhaps the greatest benefit of them all.
-tdr
Labels: Manifest Destiny, Space Frontier Conference 2005
Sunday, October 23, 2005
Smashing Comets For Fun, Education, And Profit.
Asteroids and comets are likely to be mined for their resources in a future space-based economy. Knowing the structure and composition of those objects beforehand will help to improve the odds of success. There were two speakers at the Space Frontier Foundation's annual conference this weekend who talked about that topic. One was Michael A'Hearn, the principal investigator for the Deep Impact mission.* (NASA mission website here.)
Ahearn reported on the preliminary findings from Deep Impact's collision last July 4th with the comet Tempel 1. He said the mission obtained so much data he could study it until retirement.
Here are some of his comments:
The mission flew for only 6 months in space from January to July of 2005. During that flight the spaceship encountered one "space weather event" in which the ship was saturated with radiation from the sun.
There are significant outbursts from the surface of the comet. A'Hearn showed a film clip of the impactor's approach to the comet. During the flight the view noticeably jiggled three times. These jiggles were caused by high speed impacts with milligram-sized dust particles coming off the comet.
There does not appear to be any uniformity of shape for comets. Comet Tempel 1 looks completely different from the other three comets that have been observed up close. So far the team can't explain how the surface terrain of the comet was formed. The bottom half of the comet is pocked with impact craters. (A'Hearn said that's what they were but he said in print he'll only call them craters with the characteristics of impact craters.) There is an upper portion of the comet that is also cratered but the terrain is more smooth as if the craters are older in that region. There are several distinct elevations. The bottom portion was lower than a flat plain that adjoined it, which in turn was lower than the upper portion of the comet. How the comet's flat plain was formed, he couldn't say.
The observed temperatures on the comet rule out the presence of ice on the surface of the comet. There is a region observed in shadows with lighter colored areas, which could be ice mixed in with dust but there was not enough data to make a conclusion. These lighter colored areas are more reflective than the rest of the comet, however, even those areas are pretty non-reflective. The comet is even less reflective than soot.
The heat from the sun does not appear to penetrate beneath the surface and there is ice down there fairly close to the surface. The ejecta from the impactor's collision included lots of water ice, lots of organics, all in very fine particles.
The comet's core is not very dense. The interior appears to be highly porous. The estimate is that throughout the entire core it is probably 70 percent empty space. So the comet's structural strength is very weak. Despite this, the impactor's collision did not affect the structural integrity of the comet or move the comet significantly in its orbit. The estimate is that the maximum change would be to push the comet's perihelion out about 100 meters. The collision did leave a typical gravity-formed crater.
What's the significance of this for commercial exploitation? Any prospector seeking to mine a comet will have to expect outbursts from the comet. The comet's low structural strength will complicate docking and operations on the surface. However, the presence of lots of organics and ice just below the surface improves accessibility to the resources.
-tdr
* The other speaker on this topic was Thomas Matula. He proposed a program for making investigation of Near Earth Asteroids profitable for private companies. More on that in a subsequent post.
Ahearn reported on the preliminary findings from Deep Impact's collision last July 4th with the comet Tempel 1. He said the mission obtained so much data he could study it until retirement.
Here are some of his comments:
The mission flew for only 6 months in space from January to July of 2005. During that flight the spaceship encountered one "space weather event" in which the ship was saturated with radiation from the sun.
There are significant outbursts from the surface of the comet. A'Hearn showed a film clip of the impactor's approach to the comet. During the flight the view noticeably jiggled three times. These jiggles were caused by high speed impacts with milligram-sized dust particles coming off the comet.
There does not appear to be any uniformity of shape for comets. Comet Tempel 1 looks completely different from the other three comets that have been observed up close. So far the team can't explain how the surface terrain of the comet was formed. The bottom half of the comet is pocked with impact craters. (A'Hearn said that's what they were but he said in print he'll only call them craters with the characteristics of impact craters.) There is an upper portion of the comet that is also cratered but the terrain is more smooth as if the craters are older in that region. There are several distinct elevations. The bottom portion was lower than a flat plain that adjoined it, which in turn was lower than the upper portion of the comet. How the comet's flat plain was formed, he couldn't say.
The observed temperatures on the comet rule out the presence of ice on the surface of the comet. There is a region observed in shadows with lighter colored areas, which could be ice mixed in with dust but there was not enough data to make a conclusion. These lighter colored areas are more reflective than the rest of the comet, however, even those areas are pretty non-reflective. The comet is even less reflective than soot.
The heat from the sun does not appear to penetrate beneath the surface and there is ice down there fairly close to the surface. The ejecta from the impactor's collision included lots of water ice, lots of organics, all in very fine particles.
The comet's core is not very dense. The interior appears to be highly porous. The estimate is that throughout the entire core it is probably 70 percent empty space. So the comet's structural strength is very weak. Despite this, the impactor's collision did not affect the structural integrity of the comet or move the comet significantly in its orbit. The estimate is that the maximum change would be to push the comet's perihelion out about 100 meters. The collision did leave a typical gravity-formed crater.
What's the significance of this for commercial exploitation? Any prospector seeking to mine a comet will have to expect outbursts from the comet. The comet's low structural strength will complicate docking and operations on the surface. However, the presence of lots of organics and ice just below the surface improves accessibility to the resources.
-tdr
* The other speaker on this topic was Thomas Matula. He proposed a program for making investigation of Near Earth Asteroids profitable for private companies. More on that in a subsequent post.
Labels: Manifest Destiny, Space Frontier Conference 2005
Saturday, February 19, 2005
Space Elevators of the 20th Century
It's a given among space enthusiasts that a golden age in human space exploration awaits only the development of a cheaper method to get us from down here to up there. Last year, hopes for cheap space travel rose with the successful flights of Burt Rutan's Space Ship One. If Virgin Galactic's plans to take paying passengers into outer space using Rutan's design pan out, Space Ship One's flights likely will be seen by future historians as a turning point in the Space Age, as that point in history when human space travel leaped out of the 20th Century and into the 21st.
Space Ship One's success is taking space exploration down a path most space enthusiasts did not visualize in the 20th Century. The 20th Century's dreams of humans in space were formed by the big business/big government culture of that century. Big rockets would take big ships into orbit to rendezvous with big space stations run by big corporations and big governments. The ultimate expression of that vision was Gerard K. O'Neill's High Frontier, a huge project that involved building a giant city in orbit where thousands of people would live out their lives in freedom. The High Frontier vision paid lip service to the real-world economic question of how this would all be paid for by proposing the building of giant solar panels near the space city, which would beam cheap power to the huddled masses on Earth via microwave radiation.
Everything that marked the 20th Century is there. There's the huge nature of the project, which would require funding by big government and big business. Anybody who thinks a space city funded by big government and business would be a paradise of freedom might want to do a little bit of reading on company towns before calling the moving vans. There's the attempt to make the project seem relevant to voters back home by turning the space city into a giant power station for the Earthbound. Spinoffs anyone? There's even the attempt to justify the project on environmental grounds. After all, what's cleaner than solar power? And the giant solar panels are in space. If we could move all our power stations into orbit just imagine how we could protect the Earth? Never mind that the power from space is being transmitted to Earth via microwave beams. Wouldn't want to be the flock of birds migrating through that. And what of the public that would be asked to fund the project and use the power? No matter how many government studies declare beaming energy from space to be safe, this'll sell to the public? Some people are so concerned about stray radiation from their microwave ovens that they wait a second or so after the beeping stops before opening their oven's door. Just try and build a cellphone tower or power line in a local neighborhood. You won't have to wait long before a community activist group forms to prevent the irradiation of their kids. And why go this route when we've got fuel cells around the corner, we could get more benefit from the money by paying to install solar panels on buildings around the country, and people would benefit personally from home solar systems by selling their excess power back to the grid.
We don't hear much about High Frontier these days.
It's hard to imagine another vision of the future that is more mired in the 20th Century than High Frontier but there is. What is it? Why, it's the dream of space elevators to the sky. Imagine building a 20,000 mile-high cable, securing it to a spot near the equator on Earth and a station in geo-synchronous orbit, and then attaching pressurized elevator cars to the cable. The advantage of this system is that people ride the elevator cars up the cable to the space station, much like they might ride a train today. The disadvantage of this system is that it'll never be built.
Every now and then a story appears that touts the space elevator vision. The story from space.com linked to this post's headline is no exception. According to the story, "The biggest challenge to the space elevator has been developing a cable tough enough to extend 62,000 miles without breaking." I don't think so. The biggest challenge facing the space elevator is not engineering. The real problem with the space elevator is that it's so 20th Century and we're already living in the 21st.
The space elevator is such a huge project that it could never be built by a single company or country. Look at the difficulties with international cooperation that have beset the International Space Station and try to imagine how it'll be different for a space elevator. Try to imagine the environmental impact statements required to build such a thing. Try to imagine the enormous cost of building a space elevator. Try to imagine the demands participating companies will make in exchange for their involvement. Try to imagine a future where the preferred route into space leaves from a single spot on the Earth. Then ask yourself, given all that, are elevator fares into space likely to be cheap or are they likely to be expensive? If space enthusiasts want access to space to be controlled by a giant public/private monopoly then the space elevator is the way to go.
But if space enthusiasts, who dream of the future as a better place than today, want access to space to be cheap and available to all, then Burt Rutan's Space Ship One is the way to go. Space Ship One was deceptively retro-looking. To anyone who has ever watched old Flash Gordon or Buck Rogers serials Space Ship One looked very familiar. Rutan's project was also reminiscent of the Wright Brothers. Yet, despite these links to the 20th Century, Rutan's way to space is not the 20th Century way.
Rutan's way to space rejects the 20th Century way.
The 20th Century way to space is the massive government spending, big business, top-down, politically motivated, exclusivist way to space. Rutan's way to space is the 21st Century way. What is the 21st Century way to space? It's the cheap, distributed way of the laptop versus the expensive centralized way of the mainframe, the home solar system versus the public utility's power station, the airplane versus the dirigible. It's inexpensive because it seeks a profit and doesn't spend a lot of money. It's private because it keeps control to itself rather than existing to obtain government contracts. It's focused because it seeks to go into space for the right reason, "to fulfill dreams" as Rutan famously said the day before Space Ship One's flight, not for politics. It's simple and safe because it relies on existing technology. It's bottom up and diverse because it's inexpensive, private, focused, simple, and safe.
As long as we have governments and big corporations the 20th Century's way to space will continue. But where has the 20th Century's way gotten us? That's us, not the military, not the astronauts, not the scientists, not the engineers. Us. Nowhere, that's where. The space elevator crawls to the same destination.
-tdr
Space Ship One's success is taking space exploration down a path most space enthusiasts did not visualize in the 20th Century. The 20th Century's dreams of humans in space were formed by the big business/big government culture of that century. Big rockets would take big ships into orbit to rendezvous with big space stations run by big corporations and big governments. The ultimate expression of that vision was Gerard K. O'Neill's High Frontier, a huge project that involved building a giant city in orbit where thousands of people would live out their lives in freedom. The High Frontier vision paid lip service to the real-world economic question of how this would all be paid for by proposing the building of giant solar panels near the space city, which would beam cheap power to the huddled masses on Earth via microwave radiation.
Everything that marked the 20th Century is there. There's the huge nature of the project, which would require funding by big government and big business. Anybody who thinks a space city funded by big government and business would be a paradise of freedom might want to do a little bit of reading on company towns before calling the moving vans. There's the attempt to make the project seem relevant to voters back home by turning the space city into a giant power station for the Earthbound. Spinoffs anyone? There's even the attempt to justify the project on environmental grounds. After all, what's cleaner than solar power? And the giant solar panels are in space. If we could move all our power stations into orbit just imagine how we could protect the Earth? Never mind that the power from space is being transmitted to Earth via microwave beams. Wouldn't want to be the flock of birds migrating through that. And what of the public that would be asked to fund the project and use the power? No matter how many government studies declare beaming energy from space to be safe, this'll sell to the public? Some people are so concerned about stray radiation from their microwave ovens that they wait a second or so after the beeping stops before opening their oven's door. Just try and build a cellphone tower or power line in a local neighborhood. You won't have to wait long before a community activist group forms to prevent the irradiation of their kids. And why go this route when we've got fuel cells around the corner, we could get more benefit from the money by paying to install solar panels on buildings around the country, and people would benefit personally from home solar systems by selling their excess power back to the grid.
We don't hear much about High Frontier these days.
It's hard to imagine another vision of the future that is more mired in the 20th Century than High Frontier but there is. What is it? Why, it's the dream of space elevators to the sky. Imagine building a 20,000 mile-high cable, securing it to a spot near the equator on Earth and a station in geo-synchronous orbit, and then attaching pressurized elevator cars to the cable. The advantage of this system is that people ride the elevator cars up the cable to the space station, much like they might ride a train today. The disadvantage of this system is that it'll never be built.
Every now and then a story appears that touts the space elevator vision. The story from space.com linked to this post's headline is no exception. According to the story, "The biggest challenge to the space elevator has been developing a cable tough enough to extend 62,000 miles without breaking." I don't think so. The biggest challenge facing the space elevator is not engineering. The real problem with the space elevator is that it's so 20th Century and we're already living in the 21st.
The space elevator is such a huge project that it could never be built by a single company or country. Look at the difficulties with international cooperation that have beset the International Space Station and try to imagine how it'll be different for a space elevator. Try to imagine the environmental impact statements required to build such a thing. Try to imagine the enormous cost of building a space elevator. Try to imagine the demands participating companies will make in exchange for their involvement. Try to imagine a future where the preferred route into space leaves from a single spot on the Earth. Then ask yourself, given all that, are elevator fares into space likely to be cheap or are they likely to be expensive? If space enthusiasts want access to space to be controlled by a giant public/private monopoly then the space elevator is the way to go.
But if space enthusiasts, who dream of the future as a better place than today, want access to space to be cheap and available to all, then Burt Rutan's Space Ship One is the way to go. Space Ship One was deceptively retro-looking. To anyone who has ever watched old Flash Gordon or Buck Rogers serials Space Ship One looked very familiar. Rutan's project was also reminiscent of the Wright Brothers. Yet, despite these links to the 20th Century, Rutan's way to space is not the 20th Century way.
Rutan's way to space rejects the 20th Century way.
The 20th Century way to space is the massive government spending, big business, top-down, politically motivated, exclusivist way to space. Rutan's way to space is the 21st Century way. What is the 21st Century way to space? It's the cheap, distributed way of the laptop versus the expensive centralized way of the mainframe, the home solar system versus the public utility's power station, the airplane versus the dirigible. It's inexpensive because it seeks a profit and doesn't spend a lot of money. It's private because it keeps control to itself rather than existing to obtain government contracts. It's focused because it seeks to go into space for the right reason, "to fulfill dreams" as Rutan famously said the day before Space Ship One's flight, not for politics. It's simple and safe because it relies on existing technology. It's bottom up and diverse because it's inexpensive, private, focused, simple, and safe.
As long as we have governments and big corporations the 20th Century's way to space will continue. But where has the 20th Century's way gotten us? That's us, not the military, not the astronauts, not the scientists, not the engineers. Us. Nowhere, that's where. The space elevator crawls to the same destination.
-tdr
Labels: Manifest Destiny
