Archive for the 'NASA' Category

In the previous article, the topic was Gliese 581c a Earth-like planet recently discovered. Gliese 581c is very noteworthy because this planet is located in the habitable zone of it’s “sun” (red dwarf star Gliese 581c). This means that the orbit meets the “Goldilocks principle” and it’s neither too close or too far from the heat of red dwarf sun. A lot of further research is needed to determine if 581c has other characteristics necessary for life (the presence of water has been theorized but is far from confirmed), but it has become of the most promising candidates for extraterrestrial life.

Let’s say that further tests do show an Earth-like atmosphere and large of amounts of water. We would obviously send a space probe, but could we ever send a manned mission there? Not impossible, but extremely difficult at this point because while 581c is “relatively close” it’s still 20.5 light years away (194 trillion km or 120 trillion miles) away!

This distance is extremely daunting because even at the top launch speed achieved by a space probe (the New Horizons mission to Pluto was clocked at 58,356 km/hr or 36,261 mph), it would take 379,132.96 years to get to Gliese 581c! We could launch a probe and maybe our great-(great times ~15,000)-grandchildren could analyze the data, but there is also a huge problem in that NASA is only comfortable with a lifetime of 63 years before today’s spacecraft technology will break down.

While researchers have explored in a serious matter some very exotic ways of getting there like wormholes and theoretical light-speed propulsion systems, I think it’s safe to say that we won’t be getting to Gliese 581c via Star Trek warp drive. However, more powerful propulsion systems are definitely down the road, so the commute to Gliese will probably be shortened. Regardless, it will take a long time to travel there and even microscopic cosmic dusk has a sandblasting effect that might cause serious damage and eventual long-term breakdown of the probe. A solution to that problem is that if humans were abroad, we could do the repairs necessary to keep things moving along. Repair robots could also do the job for a probe, but over thousands of years they would be just as vulnerable (even if these robots built new robots to replace themselves) and artificial intelligence does have it’s limits. This leads to probably the most feasible solution to exploring and settling Gliese 581c: a generation ship that would involve setting up a small society to live and reproduce inside a spacecraft along the long road to Gliese 581c.

Of course, this solution has its own set of unique problems. First, maintaining morale and order in this mini-society could prove to be difficult. There are stories from the Biosphere 2 project and the overall field of psychology that raise some ominous doubts about a generation ship. Biosphere 2 (Planet Earth is Biosphere 1) was an experiment were humans entered into air-tight greenhouse structure and tried to survive completely isolated from the outside. One of the biggest problems with Biosphere 2 was the psychology of humans living together in really close quarters, but the stress of not being to grow enough food is probably more to blame for the high level of tension inside. More and more studies of this nature would be needed to create a healthy mini-society for the generation ship.

The second problem would be maintaining a healthy gene pool through the years. A population of 150 would the bare minimum, but that would be cutting it close. This problem could be solved by building up a huge bank of frozen sperm and eggs, but a small population is still vulnerable to the any possible disease outbreaks and if societal breakdown does occur. The best solution would be send something like a 100,000 people that could be governed like a city. Plus, this set-up would be easily transferred to actually settling Gliese 581c as a new home. (Don’t forget the eventual goal of this ambitious mission) The serious drawback is that we would have to build an immense spacecraft, so there would probably have to be a compromise between population size and ship size.

Much more to come on intersteller travel and concepts like the generation ship. Obviously we have serious problems that we have to deal with on Biosphere 1 first, but it’s definitely something to keep on the backburner. While it’s a fun and fascinating concept to think about settling on another planet, it’s also a serious issue in case of some kind of extinction level event (ELE) that humanity can’t handle. No matter what, we can’t put it off “forever” because the Sun will become a red giant star one day. Notice that forever is in quotation remarks because that day is 4-5 billion years away. Interesting fact: the Earth won’t actually engulfed by the Sun as previously thought. Recent research has concluded that the Earth will be pushed away as the Sun enters the red giant phase, but all the water and atmosphere will be boiled away so our great-(great times ~160 million)-grandchildren will be pretty much screwed at that point.

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

Sources:
1. “Stunning new planet discovery”, previous article on this blog.

2. “Interstellar travel”, Wikipedia entry

3. “Biosphere 2″, Wikipedia entry

4. “Sun”, Wikipedia entry

In a previous article, the topic was the plaques attached to the Pioneer 10 and 11 space probes. This post is about another cosmic message in a bottle, the Voyager Golden Records. As of this writing (March 18, 2007), the probes Voyager 1 and 2 are 101.957 AU and 82.529 AU from Earth. Depending on language use, “AU” or “u.a.” stands for Astronomical Unit, the distance of the semi-major axis (half of the major axis, the longest diameter of an eclipse) of Earth’s elliptical orbit around the Sun. The value of an AU unit is 149,597,870,691 +/- 30 m, about 150 km, or about 93 million miles. This puts Voyager 1 & 2 at about 9.5 billion miles (15.3 billion km) and 7.7 million miles (12.3 billion km) from Earth.

Aboard these two probes is a golden phonograph record that contains sounds and pictures from our planet. Below is a picture of the Voyager craft, at the center of the picture you can see the cover of the 12-inch Golden Record.

The cover is a instruction sheet for playing the record that is written in binary code and the spin movements of a hydrogen atom as the timing basis. This far more sophisticated message in a bottle presents has serious limitations as an effective way to communicate with intelligent life. Even if DJ Little Green Man is smart enough to figure out how to scratch out some tracks from this album over the alien airwaves, they may not have the visual or hearing abilities to process the sights and sounds, let alone understand what it’s on it.

Here’s here’s larger image of the cover diagram via Wikipedia’s Wikimedia feature.

However, it’s still a romantic idea and as President Jimmy Carter’s printed message on the record said: “We cast this message into the cosmos… Of the 200 billion stars in the Milky Way galaxy, some — perhaps many — may have inhabited planets and space faring civilizations. If one such civilization intercepts Voyager and can understand these recorded contents, here is our message: We are trying to survive our time so we may live into yours. We hope some day, having solved the problems we face, to join a community of Galactic Civilizations. This record represents our hope and our determination and our goodwill in a vast and awesome universe.”

Here’s links to content if you are interested:
Images
Greetings in 55 languages
Music
Sounds of Earth

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

Sources:
1. Current location data from the probes Pioneer 10, Pioneer 11, Voyager 1, Voyager 2, and last years launch of the New Horizons mission: Spacecraft escaping the Solar System”, Heavens Above website
2. “Astronomical Unit”, Wikipedia entry
3. “Voyager Golden Record”, Wikipedia entry

As you are reading this, the Pioneer 10 and 11 space probes have lost all power and are silently flying in the darkness of space. NASA lost contact with Pioneer 10 in 2003 and Pioneer 11 in 1995. Odds are that they will continue their lonely journey into eternity. However, there is a very slim, but not impossible chance that a intelligent civilization living on a different planet will detect these probes.

If this amazing event were to happen, these beings will find a golden plaque on each probe. On these gold-plated aluminum plaques are a depiction of Earth’s location in the galaxy, a diagram of the hydrogen atom, a map of the Pioneer’s journey through the solar system, and a picture of a man and woman.

Obviously this is a true shot in the dark, but I just love this cosmic “message in a bottle”. One question that comes to mind is: “would an intelligent alien be able to understand the plaque?”

Stay tuned for upcoming articles that take a tour of the plaque. Each element of the plaque is a science lesson in itself. For example, the use of the arrow to describe the gravity slingshot around Jupiter was criticized because an arrow is symbol that stems from the hunter-gather aspects of past (and present in some cases) human civilization. If our intelligent “neighbors” developed their civilization under water, the arrow could be totally meaningless.

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

Source:
“Pioneer plaque”, Wikipedia entry

This picture was taken by the Voyager 1 spacecraft on February 14, 1990 at a distance of 4 billion miles away from Earth. The idea for the picture was advocated by the famous astronomer Carl Sagan. In his book Pale Blue Dot, he wrote the following in regards to this famous picture:

“We succeeded in taking that picture [from deep space], and if you look at it, you see a dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there — on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors, so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light.

Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves. The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand. It has been said that astronomy is a humbling and character building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.”

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

I really liked how former Vice-President talked about the famous “Earthrise” picture in his book An Inconvenient Truth. This famous picture taken by the Apollo 8 astronauts as they traveled around the Moon. Seeing this picture had a powerful impact on how humanity viewed its home.

Al Gore included a poem written by Archibald MacLeish that was inspired by this picture.

“To see the Earth as it truly is, small and blue and beautiful in that eternal silence where it floats, is to see ourselves as riders on the Earth together, brothers on that bright loveliness in the eternal cold–brothers who know now that they are truly brothers.”

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

One of many items on my “things to do before I die” list, is see a major aurora borealis (Northern Lights) event. I’ve seen a few here in Wisconsin, but they are nothing compared to the beautiful nighttime shows that take place in polar locations like Alaska. Or visit the Southern Hemisphere for a Southern Lights or aurora australis show. (australis is Latin for “of the south”)

What causes the auroras?
Like any nuclear reaction, the thermonuclear reactor that is our Sun emits a steady flow of hot plasma from it’s million-degree outer surface known as solar wind. (Plasma is a gas of free electrons and positions ions – as matter becomes more energetic it goes from solid to liquid to gas to plasma – this is a energy state so hot that the atoms break apart into separate particles). This stream of charged particles flows towards the Earth at about 400km/s (about 15,000 mph) and for the most part, the flows smoothly around the Earth’s protective magnetosphere and continues onward towards space. However, there are occasional disruptions which cause the particles to barrel down towards the Earth. These highly energized particles collide with gas molecules in the upper atmosphere and induces them into an excited energy state. As the gas molecule cools down to it’s original energy state it releases the stunning greens, blues, reds, and whites of the aurora.

While everyone agrees how breathtaking auroras are, there is debate among scientists about the mechanism of these disruptions that cause geomagnetic storms. On Saturday, NASA launched a Delta II rocket carrying five identical probes of the THEMIS mission that will work together to analyze the geomagnetic storms. Not only will the five probes be working on the case, there will a great collaboration between satellites of the European Space Agency’s Cluster mission, the Double Star mission of the Chinese space agency, and 20 ground stations in Alaska and Canada.

Stay tuned for updates on the THEMIS mission, auroras, and how the activity of sun affects our daily lives in the obvious and not so obvious ways.

Interesting factoid: THEMIS stands for Time History of Events and Macroscale Interactions during Substorms. That’s a mouthful, but a simpler factoid behind the mission name is that Themis is the mythological Greek goddess of justice, wisdom, good counsel, and the guardian of oaths.

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew

Sources:
1. Official webpage of NASA’s THEMIS mission”
2. “NASA’s Aurora mission blasts off”, BBC article
3. “Aurora (astronomy)”, Wikipedia entry

Thanks to the work of NASA’s Mars Reconnaissance Orbiter (MRO), there is now additional evidence that water might have (and may still) flow on the surface.

The MRO captured images of a hilly landscape consisting of bands of light and dark rock in Candor Chasma, part of the Mars rift valley Valles Marineris. These bands are very similar to band found on earth where there is a cycle of water. In addition, researchers from the University of Arizona described numerous “halos” of bleached rock were cracks (the official term is joints) in the surface where the surface rock clearly reacted some kind of fluid. This fluid, whether it be water or liquid carbon dioxide probably came from underground reservoirs.

Like with story a couple months of very recent erosion on a crater (within a few year), it’s uncertain whether this was caused water or liquid carbon dioxide. Nevertheless, this story is still very significant because these halos would be a good place to look for evidence of life. These haloes were once underground, but have been exposed due to erosion. Back in the day, the overlying rock would have been a great shield from the harsh Martian atmosphere while life was supported below by underground reservoirs.

For some pictures of the Candor Chasma check out the BBC article on this story. They have three pictures from the original research article published journal Science that you can enlarge for a better look.

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Posted by Tim Roth, author of the political blog Think Anew and Act Anew