Habitable Exoplanets

Posted on April 9, 2013 by kevinm387

Habitable Exoplanets

Researchers at the University of Puerto Rico at Arecibo have developed a rank ordering system of comparing exoplanets to Earth called the Earth Similarity Index. Using this system, scientists have been able to highlight a few exoplanets similar to Earth and have determined which ones are the most similar to Earth. To visit the website, click the photo.

What struck me most about these planets is that none of them are really that similar to Earth. Each one is at least a few times larger than Earth in mass and/or much closer to their star than Earth. Of course, large masses and proximity to the star make these exoplanets easier to detect, but it still seems that none of these exoplanets would be able to support intelligent life as we know it. However, I am sure that many more exoplanets exist that are far more similar to Earth, however an exoplanet orbiting a distant star at Earth’s size and distance would be extremely difficult to detect. We just have to hope that technology improves enough to allow us to study these planets more in depth.


Posted in Exoplanets | Tagged , , , | Comments Off on Habitable Exoplanets

Chemical Activity on Titan

Posted on April 9, 2013 by Will K

New research shows that Titan may be more chemically active near the surface than we previously thought.

 

Scientists at NASA now believe that Saturn’s moon Titan is much more chemically active than we previously thought. According to Astronomy Magazine, the found that the “complex organic chemistry that could eventually lead to the building blocks of life extends lower in the atmosphere than previously thought.” This is activity in the lower atmosphere greatly increases the chance of microorganisms on or beneath the moon’s surface!

When Voyager flew past Saturn and captured data from Titan we saw the thick atmosphere surrounding the moon. The hydrocarbons in this smog could bond with other elements to form many different complex compounds. We’ve known that Titan’s upper atmosphere is very active in this sense, but until now we could only assume that the activity calmed down closer to the surface. Now we know that this isn’t the case and that complex organic compounds can form in the lower atmosphere just as well as the can in the upper atmosphere. These lower organic compounds can then interact with the solid and liquid compounds on the surface, either forming new compounds or soaking through the curst to liquid water below the surface. This is very exciting because when complex compound like these interact with liquid water they can turn into molecules like amino acids and nucleotide bases, fundamental components of RNA!

With this new discovery Titan has become an even more likely candidate for extraterrestrial life. Hopefully we will have the opportunity to send a future probe to Titan to take a look at what is really on and underneath the surface.

 


Posted in Moons | Tagged , , , | Comments Off on Chemical Activity on Titan

We Are The Aliens

Posted on April 9, 2013 by surujdeka


We have always questioned if Earth is the only planet capable of sustaining life in the universe and whether one day, we will get to meet real life extraterrestrials. Well, if new evidence is to be believed, all we might have to do to look at aliens is go look at a mirror.

Researchers at the University of California, Berkeley and at University of Hawaii proved in an experiment that complex compounds necessary to sustain biological processes on Earth might have been delivered to Earth by comets and asteroids. These compounds are amino acids called dipeptides which are the building blocks in a way for proteins, enzymes and sugars (all of which are essential for life processes). In the experiment, the scientists simulated an icy comet being hit by cosmic rays in space by bombarding a silver puck in an ultra high vacuum chamber. Amazingly, the scientists found up to nine different amino acids and dipeptides formed on the surface of these pucks! These results suggested that comets being hit similarly in space by cosmic rays might have produced these compounds which then were transferred to the Earth on impact.

It is already well known that water and other hydrocarbons reached Earth on comets that hit our planet. But it wasn’t known until now how more complex compounds began to form afterwards. If this experiment is correct, that would mean that comets like the ones that gave us life could have easily bombarded other planets and seeded those planets with the early beginnings of life too. This theory that life on Earth came from elsewhere in the Universe via asteroids and comets is called Panspermia. According to this theory, and it is more than plausible, we might be the ones alien to this planet.


Posted in Class | Tagged , , , , , | Comments Off on We Are The Aliens

The Galilean Moons of Jupiter

Posted on April 9, 2013 by staunesm

Image

With the constant discovery of more and more objects in space, it is difficult to keep track of the planets, moons, asteroids, comets, and exosolar planets that we already know and love.  Therefore I am using this blog as an opportunity to discuss the four largest moons of Jupiter: Io, Europa, Ganymede, and Castillo.

Let’s start with Io. Io is the fourth largest moon in the solar system, the innermost moon to Jupiter, and is known for its volcanic activity.  This volcanic activity is primarily due to tidal heating.  The volcanic activity is the reason for different colorings and the surface changes on Io, and it’s material also creates Io’s thin atmosphere.  Most importantly, it is key to remember that Io is the most geologically active object in the Solar System. Must be entertaining to see:)

After Io we have Europa, what is potentially the best current option for a viable life form in addition to Earth. From the diagram above, it is easy to see that Europa is the smallest of the four Galilean Moons, yet it is still a large moon in comparison to others within the solar system.  Europa’s atmosphere contains abundant oxygen, which is one of it’s most intriguing characteristics when thinking about other life forms. There is the potential of water on Europa as the fly-by mission of 1989 showed a young surface, but there is no solidified evidence.  Unfortunately, although Europa seems to have the most hope for life, there are no future missions in the next few years scheduled to check it out.

Moving along we get to Ganymede. When I think Ganymede, I think great.  That is because Ganymede is the largest moon in the Solar System! The surface of Ganymede has both old and young features, with the potential of an ocean deep within.  One cool thing about Ganymede is that is has a magnetosphere due to the convection process. You are probably wondering what this giant moon is made of: silicate rock and water ice.  Now that’s a combination for ya.

The last Galilean Moon is Callisto. Callisto is unique because it does not have orbital resonance that is attributable to the other three Galilean Moons and therefore Callisto does not experience tidal heating. In class we learned that Callisto represented cratering.  This cratering is due to the fact that Callisto’s surface is very old, and there is no geological activity such as volcanism or plate tectonics to cover the craters.  One fun fact about Callisto- its surface is asymmetric causing the trailing hemisphere to be lighter than the leading one.

In all, I hope this blog helped outline the main points to remember about the four Galilean Moons of Jupiter. Although a lot of information, remember simple techniques like Callisto-Cratering or Great Ganymede can help you to remember the moon’s characteristics!

Overview Io Europa Ganymede Callisto


Posted in Moons | Tagged , , , , , , , | Comments Off on The Galilean Moons of Jupiter

Exoplanets in the Habitable Zone

Posted on April 9, 2013 by Will K

Research shows that there may be more Earth sized planets in the habitable zone than expected.

 

According to recent astronomical discoveries, there are much more Earth sized exoplanets in the habitable zone than scientists previously thought. In a study of cool stars, called M-dwarfs, researchers found that rocky, medium sized exoplanets could be relatively common. The possibility of a moderate climate and liquid water is greater for these planets when they are at the appropriate distance from their star, making them top priority for astronomers looking for life.

The researchers decided to study M-dwarf stars because the orbits of planets around these stars are much shorter than they are around more massive stars. This shorter orbit allows researchers to track the transit of planets more frequently, allowing them to collect much more data. In addition, there are several M-dwarf stars near to our Solar System, allowing for easier observation and tracking.

The greater number of M-dwarf stars in the area means that there could be several Earth sized planets relatively close by. Science Daily reports that “There are about eight cool stars within 10 light-years, so conservatively, we should expect to find about three Earth-sized planets in the habitable zones.” This is really good news for scientists in search of extraterrestrial life! With such good possibilities of life so close by there is no telling what we will find in the near future.


Posted in Exoplanets | Tagged , | Comments Off on Exoplanets in the Habitable Zone

Creating Life

Posted on April 9, 2013 by charlesbcochran

Image

You might think this is Earth, but this is something much more intriguing………

Many years from now, humanity will be threatened by a plethora of factors that will cause the inevitable. Humans will have to seek refuge somewhere other than Earth. Wait, this is impossible right? The curiosity rover has clearly shown that Mars is inhabitable, the moon has no atmosphere, and we do not have the capacity to travel beyond our solar system. So what is the alternative? Terraforming. A word unknown to many (including myself prior to research), terraforming revolves around intentionally modifying an atmosphere to promote life. While this proposition sounds ludicrous, evidence can be seen directly on Earth. This is through how we have modified our atmosphere through the greenhouse to literally warm our planet. Could we do the same to Mars to make it habitable to humans? Several components need to happen for this to occur. The planet needs to be warmed substantially and an atmosphere must be created and sustained. There is plenty of CO2 locked in ice on Mars, and if melted through climate warming, could release levels that would create an atmosphere similar to that on the top of Mt. Everest.

However, even if an atmosphere were formed, solar radiation would sweep much of it away. This is due to the fact that Mars’ core is cold and essentially dead. To re-activate this core and create a magnetic field that would then sustain an atmosphere, several methods have been proposed. In the past it is theorized that incoming asteroids provided a temporary gravitational pull on Mars which generated a magnetic field. This raises the question if adding a moon around Mars could re-generate this field. Other theories include firing up the core through radioactive substances and creating artificial magnetic fields.

The point is, with our knowledge today, it does appear that terraforming Mars is feasible.

Not easy by any point, yet feasible. It will be interesting to watch the development of our knowledge of terraforming to see if it will eventually become a possibility or a reality. Probably not in our lifetime, yet the prospect is fascinating.

Check out these links if you want further research:

Is it possible to terraform Mars?

Video – Terraforming Mars


Posted in Class | Tagged , , | Comments Off on Creating Life

Finding Exoplanets – Gravitational Microlensing

Posted on April 8, 2013 by charlesbcochran

The search for exoplanets is difficult. Even more so when the method of gravitational microlensing is used. Back in the day, Einstein proved the existence of gravitational lensing. Basically what happens is when a distant and close star are aligned with earth, the close star magnifies the distant star. This is because the gravity of the closer star actually bends the light by creating warps in spacetime. As a result of this light bending around the closer star in multiple routes, the distant star will appear magnified to us. Adding an extrasolar planet into the mix, and in addition to this increase in brightness of the distant star, when the planet is perfectly aligned as well there will be another increase in the brightness of the distant star, but much less noticeable except on a much smaller scale.

Already it is clear why it is so difficult to find extrasolar planets by microlensing. The timing required for this lensing effect has to be perfect, with telescopes fixed on certain stars for long periods of time waiting for this event to happen. Since it is so rare that this event happens, it makes sense that very few extrasolar planets have been found using this technique compared to other techniques. However, it is fascinating that this method has been proven to work.

699 planets have been found, and only 24 of these based on this method. Still, this number is significant.

In addition to the limitations of the nature of this search, additionally microlensing provides no data to the details of the planet such as mass, orbital period, etc.

Still, I highly suggest learning more about this method as the history and potential of it is impressive. Already scientists are claiming they have found some of the most distant objects in the universe ever recorded through gravitational lensing using distant galaxies as lenses.

For further research about this distant galaxy I recommend this news article:

http://arstechnica.com/science/2012/11/gravitational-lens-magnifies-earliest-galaxy-yet-seen/

Also, for anyone with some spare time on their hands I highly recommend the book “Einstein’s Telescope”, which covers the more nitty gritty details of lensing, in a non-overbearing or overwhelming way.


Posted in Class | Tagged , , | Comments Off on Finding Exoplanets – Gravitational Microlensing

Final Maven Instrument for Mars

Posted on April 8, 2013 by indianwm

The instrument above will be fitted on Mars Atmosphere and Volotile and Evolution spacecraft, or MAVEN. This instrument is a spectrometer for neutral gas and ion mass which will test the upper atmosphere of Mars. This instrument is important so we can understand the changes that have occurred within the upper atmosphere and analyze the rate at which it has lost gas. By studying the information we receive from this exploration, we may be able to determine whether or not Mars was once a suitable environment for life. This MAVEN craft is the first to explore these aspects of Mars and is an extremely exciting mission for the scientist involved. By utilizing these advanced instruments on the MAVEN, we should be able to see what the history for water is on Mars and how that was affected by the loss of atmospheric gas. Therefor, we should find out some exciting news in the near future.

MAVEN

Posted in Instruments, Observables, Space Travel | Tagged , , , | Comments Off on Final Maven Instrument for Mars

Why Pluto is Not a Planet

Posted on April 8, 2013 by indianwm

This informative video talks about Pluto, from discovery to why it is no longer considered a planet, but a dwarf planet. The discovery of Pluto was in 1930 by a man named Clyde Tombaugh in Arizona. Since this time Pluto has been classified as a Dwarf Planet. It lays in the Kuiper belt beyond Neptune along with many other large objects. Pluto is just one of thousands of other very similar objects in this area in the outer solar system. As our knowledge of space and our solar system increased, so did our understanding of Pluto. In 2005, we began to realize that our solar system contained less true planets than we previously believed. This occurred when we discovered the existence of larger objects beyond Pluto in the outer solar system. The three components that determine a planet are: the object needs to orbit the sun, there needs to be enough gravity in order to create a spherical shape, and it should clear its orbit of smaller objects. Pluto fits the first two requirements but fails the third. Therefore, Pluto became a Dwarf Planet and we lost the 9 planet solar system. There was a large discussion, but at the XXVIth General Assembly of the International Astronomical Union in 2006, the decision was made that Pluto was no longer a planet. It was a sad day for me and the majority of the world who had grown up with Pluto as the ninth planet, but after looking at the facts, it is clear why.

Pluto not a planet


Posted in Historical, Observables | Tagged , , , | Comments Off on Why Pluto is Not a Planet

Green Peas Shed Light On Universe Beginnings

Posted on April 7, 2013 by wherrysg

Image

Image Source

In 2007, astronomers made a discovery of what they called the Green Pea galaxies. These galaxies are those that are undergoing high rates of star formation and help us understand reionization–which is an extremely important process in the development of our universe. Reionization by definition is “the process that reionized matter in the universe after the dark ages of the Big Bang, and is the second of two major phase transitions of gas in the universe.” Basically, this process helped our universe and its galaxies become what it is today. To me, the existence of these Green Pea galaxies is cool because I didn’t know that the Big Bang occurred in phases and it is especially neat that we have special galaxies today that can tell us more about that history. For more information about how astronomers observe these galaxies and what they tell us, check out this article.


Posted in Galaxies, Historical | Tagged , , , , , , , , | Comments Off on Green Peas Shed Light On Universe Beginnings