Finding Extraterrestrial Life on Europa

Jupiter Europa

Earlier this week, we learned during a NASA press conference that scientists have discovered huge active plumes containing water vapor being released from the surface of Jupiter’s moon Europa. This sensational find was made using the NASA/ESA Hubble Space Telescope. Joachim Saur, professor at the Institute for Geophysics and Meteorology of the University of Cologne was principal investigator of the Hubble observing campaign. Read More →

What Aliens From Another World Will Look Like

Silicon Alien

Invading aliens from outer space won’t look like a Lady Gaga zombie or creatures with serious nasal drip problems. Top planetary scientists have now come up with different sketches of how aliens might appear. Here, then, are what real aliens will most likely look like if they drop on your house. Read More →

Could Life Have Survived a Fall to Earth?

Asteroid impacting Earth's oceans. Credit: NASA/Don Davis

Asteroid impacting Earth’s oceans. Credit: NASA/Don Davis

It sounds like science fiction, but the theory of panspermia, in which life can naturally transfer between planets, is considered a serious hypothesis by planetary scientists. The suggestion that life did not originate on Earth but came from elsewhere in the universe (for instance, Mars), is one possible variant of panspermia. Planets and moons were heavily bombarded by meteorites when the Solar System was young, throwing lots of material back into space. Meteorites made of Mars rock are occasionally found on Earth to this day, so it is quite plausible that simple life forms like yeasts or bacteria could have been carried on them. Read More →

Reaching E.T. Through Standardized Protocols

Image Credit: SPDO/TDP/DRAO/Swinburne Astronomy

Image Credit: SPDO/TDP/DRAO/Swinburne Astronomy

Choosing a single telecommunications protocol has always been difficult for engineers on Earth, so it’s especially difficult for those who want to communicate with beings from another star system. While it’s nice to imagine that extraterrestrial beings would be able to interface with whatever protocol humans decide to encode a message in, that’s not a realistic way to think. Humanity has developed countless electronic communication technologies since the 19th century. There’s no reason to believe that extraterrestrial beings haven’t done the same thing.

SETI and METI organizations have developed a single protocol for sending messages to potential examples of intelligent life. There’s no way of knowing if another civilization could ever actually interpret these signals but the odds are at least a little better with standardized systems.

Imagine an engineer trying to decode a data transmission that no one had ever encountered before. They’d probably try to compare it to other transmissions sent with the same protocol, and then look for the symbols that appear the most. These symbols are probably encoding the most common glyphs in the written language that the transmission represents.

Now imagine that each transmission that the engineer encounters is in a different code. There’s no way for them to compare different messages, because there aren’t any similarities between the different protocols. By using a single system, Earthlings are giving extraterrestrial cultures a chance to decode messages by comparing them to one another. It wouldn’t have been possible for international communications to be achieved on Earth if everyone decided to use their own technology standards.

In fact, poor choices in the past have hampered many types of technological developments. If standardization had occurred between Earthbound transmission sites years ago, these problems would never have reared their ugly head. For that matter, extraterrestrials might very well have been able to intercept numerous types of incidental transmissions. If signals are as weak as one might expect them to be, every little bit matters when we’re talking about communicating across the universe.

If standardization is important, the types of signals sent are equally important (if not more so). Most scientists agree that radio waves are the best way to communicate with other planets/stars given our current level of knowledge. This is due to the fact that radio waves are able to traverse the vast distances involved in actually reaching other stars/planets outside the Milky Way galaxy. Even the closest stars are about 6 light-years away (each light-year is roughly 6 trillion miles). This means that any signals we send their way have to cut through enormous amounts of gas and other obstructions found in space. Radio waves are able to do this effectively (as opposed to say, lightwaves) while traveling vast distances at the speed of light. I have read the work of some scientists that believe lasers may be a good way to reach extraterrestrials as well. I personally feel this is a great alternative to microwaves alone.

electromagnetic-spectrum

While standardization and appropriate signal types are invaluable, they’re also practical because they help to reduce costs. While practicality isn’t something that most people like to discuss, it’s actually pretty necessary in the world of SETI/METI. Many of these organizations, such as the SETI Institute (SETI Institute listens for signals vs. transmitting signals), survive on public donations. They need to maximize what they get out of the financial resources that they’re given to work with. Developing a single standard algorithm helps to reduce the amount of money spent on research while maximizing the chances of success (choosing the right type of signal to send) are crucial to long-term survival. It also means that different pieces of equipment will always interface properly. This means that expensive converts/integrations won’t ever be necessary as long as everyone adheres to the existing standard.

From an engineering standpoint, these groups might want to look at their antennas and transmission sites next (in terms of standardization). Once protocols are standardized, they can begin to improve in other areas as well. Each little bit matters when trying to talk to someone that may exist on a planet that is trillions of miles away.

Reference:

Atri, D., DeMarines, J., & Haqq-Misra, J. (2011). A protocol for messaging to extraterrestrial intelligence Space Policy, 27 (3), 165-169 DOI: 10.1016/j.spacepol.2011.01.001

Edmondson, W. (2010). Targets and SETI: Shared motivations, life signatures and asymmetric SETI Acta Astronautica, 67 (11-12), 1410-1418 DOI: 10.1016/j.actaastro.2010.01.017

ResearchBlogging.org

Are Rocks the Key to Finding Extraterrestrial Life?

While scientists like to bandy origin of life theories around, they seldom make the connection to astrobiological research. These theories, however, have a lot to suggest about how life may have developed on other worlds. According to recent studies, low-density vesicular volcanic rock material like pumice might have acted as something like a natural laboratory for chemical reactants that produced the so-called primordial soup. Early geological records show that pumice clasts were abundant in the approximate 3,460 Ma era period.

Samples collected from the Pilbara region in Western Australia exhibit signs of carbon. Traces of titanium oxide and iron sulfide were also found in the samples. Both of these are catalysts for certain reactions that suggest basic life processes. Other researchers have pointed to aluminosilicate minerals in the geological samples, which might be some sort of remains left by prokaryote life forms. Early prokaryotes might have colonized the clasts before they were buried, and therefore what scientists are currently examining are modified forms of what would have otherwise been regular rocks.

In any case, these are some of the earliest examples of life forms currently known to researchers. By examining these samples, it’s somewhat same to assume that a profile can be put together of what substances to look for when searching for remnants of life in astronomical materials. Asteroids are probably what have been covered the most in these studies, but they aren’t the only places to search. If a meteorite were to strike Earth that resembles these clasts, it would pretty exciting nevertheless.

When taking soil samples from other planets, researchers haven’t always been sure what they’re looking for. The Viking probes on Mars attempted to incubate microbes, and this proved relatively fruitless. However, future missions could instead try to locate geological samples that resemble those collected from the Pilbara region. There are plenty of samples in laboratory storage facilities anyway, and these could be examined without any real problems if permission could be granted to scientists.

That’s assuming that evolution takes an identical path on every planet. While some people might suggest this is a shortsighted way to look at the problem, it does have the benefit of making the fewest assumptions. Either way, there’s no reason not to take a look at existing rock samples to see if they match any of these chemical configurations. There’s little risk, and the benefit for a pretty impressive reward if successful.

Reference:

Martin D. Brasiera, Richard Matthewmana, Sean McMahonb, Matt R. Kilburnc, & David Wacey (2013). Pumice from the ∼3460 Ma Apex Basalt, Western Australia: A natural laboratory for the early biosphere Precambrian Research, 224, 1-10 : 10.1016/j.precamres.2012.09.008

ResearchBlogging.org

Using METI Satellites to Find E.T.

Cellular networks are all the rage these days. A lot of people believe that mobile technologies will eventually replace desktops/laptops entirely. Regardless, they only work with terrestrial communications networks here on Earth. What if a similar network could be built beyond our planet? Considering that all electromagnetic radiation travels at the speed of light, the problem posed by interstellar communication is a pretty big one but may be the best shot we have at communicating with intelligent alien lifeforms (if they do in fact exist out there).

Messaging to Extra-Terrestrial Intelligence (METI) is the process by which astronomers attempt to purposefully communicate with alien life forms. All forms of electromagnetic radiation emitted from Earth, including radio waves from cellular phones, are moving in a shell at a constant rate away from our planet. That being said, this data isn’t particularly useful. It’s going to take a long time for it to reach a destination. If extraterrestrials were listening to any messages previously transmitted from Earth, it would probably be well over 100 years old.

There are plenty of other things that interfere with METI systems. Scattering, the Doppler effect, noise, signal attenuation and dispersion are all major issues. Signal attenuation is perhaps the most difficult to overcome since such great distances are involved. One might propose, then, that a system of interstellar repeaters would be an excellent way to conquer the ether of outer space.

Translator towers are often used to fill in the holes of FM broadcaster coverage maps. Likewise, cell towers overlap one another to provide a seamless web of communication. Many people even complain that humanity is quickly becoming far too connected for their own good. That being said, this sort of network model could just as easily be adapted to interstellar communication.

No one can build a system of interconnected satellites emitting METI messages overnight. It would probably take hundreds of years. That being said, many places in ancient times were settled in the same way. People built a settlement on an island or cliff and lived there for decades. Eventually, some adventurers from that town would move around and settle a new area. Likewise, that new dispersed settlement would produce another generation of adventures.

Some people have proposed constructing satellites in this manner to relay messages in the hope of making contact with an alien race. One could perhaps imagine making machines that use nanotechnology to continue expanding across a wide stretch of space. Of course, that comes with it’s own set of difficult questions. Either way, this is a difficult task (but not insurmountable). We’re actively listening for E.T. Perhaps it’s time for us to begin calling them as well.

Reference:

Messerschmitt, D., & Morrison, I. (2012). Design of interstellar digital communication links: Some insights from communication engineering Acta Astronautica, 78, 80-89 DOI: 10.1016/j.actaastro.2011.10.005

ResearchBlogging.org

Exo-Political Policymaking: Power to the People, Regardless of Species

Nikolai Kardashev once speculated that advanced extraterrestrial civilizations could be classified by their energy usage. While energy conservation is stressed on Earth, energy is vast in space. Therefore, societies that have already journeyed to the stars can [theoretically] experience growth in ways that humanity can only dream of. He proposed that the first step in extraterrestrial development was the planetary level.

Background Reading [PDF]: Discipline of Choice for Public Policy Issues Concerning Extraterrestrial Life

Beings that had developed societies at the planetary level could be classified as Type I cultures. Humanity could be called a Type I culture. Type II civilizations used all of the power present in a star system. Species living in a Type III society would use power at the galactic level.

Public policy decisions surrounding extraterrestrial life have to be tempered around the possibility of coming into contact with members of different levels of technology. Scientific speculation illustrates the possibility of far more Type I societies than either of the other two classifications. Likewise, one might assume that most extraterrestrial life is microbial. Nevertheless, one could just as easily argue that visitors from another world would need to be at the galactic stage of development in order to survive the incredible voyage between two star systems. Trips could take immeasurable amounts of time at faster than light speeds. Sub-light vessels might take centuries to travel from one star to another.

Information on research surrounding the subject of extraterrestrial life has made policy decisions rather difficult. Governmental organizations are already pressured to make logical decisions regarding the possibility of contact with alien races. However, to what degree the public should know about these things is a major ethical question.

Freedom of Information Act mandates caused numerous US federal documents to be placed online. French documents were posted in 2007. The United Kingdom followed suit in 2008. Only time will tell what changes in public policy these documents will force.

It’s highly unlikely anyone will come across some sort of alien cover-up, but these do provide a framework for exo-political decision-making. Governments could then feel that passing laws dealing with extraterrestrial civilizations are normal. There would be plenty of consequences from that happening.

Additional Learning Resources:

The Murchison Meteorite Revisited

Piece of the Murchison meteorite

While it took researchers years to prove it, the Murchison meteorite had a number of extraterrestrial organic compounds in it. Four decades is a long time when it comes to space exploration. Forty years is a long time to do anything for that matter. However, this is a serious triumph for science. Read More →

Film Influence on Our Consciousness

Theorists have sometimes stressed that The Day The Earth Stood Still had a profound influence on the collective consciousness. Gort’s visit to Earth was witnessed on the silver screen across the globe in 1951. His mission seemed peaceful, despite his methods. Indeed, some people have suggested that the Klaatu character might have held religious significance.

Other film critics feel that his mission was unsettling, and that it meant extraterrestrial forces cared little about the Earth’s people. Regardless of which stance one takes, it’s easy to see that the film changed the way that people look at the human condition. It might also have caused many of the supposed UFO sittings of that time period.

Viewers might have subconsciously been influenced by the film’s depiction of otherworldly beings. They might very well have ultimately convinced themselves that they were able to see flying saucers around them. Mass delusion is a realistic explanation. It’s important to understand, however, that this neither proves nor disproves the existence of extraterrestrial life forms. It doesn’t even suggest that all alien spacecrafts viewed during the time period were phony. All it shows is that other forces may have been at work. Only an appropriate exploration program could truly provide proof either way.

Future Mission to 51 Pegasi

Due to their proximity to Earth, many of the closest star systems have been extensively studied. When the mass media gets their hands on research, they go wild with it. This is a very human response. Naturally, many individuals want to find proof of extraterrestrial life. Other people want to find places where humanity can expand. Some people might simply have some sort of fantasy fulfilled by being an armchair astronaut.

In 1995 astronomers announced that they had discovered a planet, 51 Pegasi B, in orbit around its star, 51 Pegasi – the first exoplanet found orbiting a star similar to the Sun. If one were to travel 48 light-years from this world, they might happen upon a fifth-magnitude star with a mass that’s almost 47 percent higher than that of Jupiter. The planet in that system orbits extremely close to the stellar body. This might very well suggest that the world could never have supported life.

However, that means very little and long-range planning and missions to these systems should still be planned. Though faster than light travel is still out of reach, even conventional systems could theoretically take an artificial intelligence unit to another star system. While it might take decades to reach another world, the whole of humanity would be better for it – especially if life were discovered.

I’m all for going back to the moon (human exploration). It’s a feasible idea (given that we’ve done it before) and certainly a candidate for early space colonization. That being said, I think we should stop focusing on manned missions to Mars [PDF] for now, and focus instead on sending machines to conduct long-term planetary exploration and discovery missions. Ancestors of today’s scientists will surely reap the benefits of such journeys in the far future as a result of our efforts right now.

Image Credit: BBC