Planet-hunting

Posted on April 1, 2017 by Afi Mohd Sayuti

Artist's impression of the planet orbiting Proxima Centauri

Image of the Surface of Proxima b

Why would people live on other planet? Wouldn’t our Earth suffice the human needs? The answer is absolutely. But wouldn’t it be nice to discover some other worlds other than ours? What if there are actual lives out there besides humans who proclaimed to be the dominant of the entire species? The degree of narcissism of human designation of dominance is undeniable yet arguably, could be challenged by other species on some distant worlds.

Proxima b, is the closest (known) exoplanet (or an extrasolar planet)  from our solar system that is potentially habitable. Proxima b is a planet that orbits around the red dwarf triple star system called Proxima Centauri which is far smaller and cooler than our Sun. This planet is 4.2 light years from our Earth.

What’s so special about Proxima b other than it being the closest to us? Well because of its close distance, this planet has temperature mild enough for water to pool on the surface of the planet, just like our Earth. Water is the essence of life! Proxima b is a rocky planet in the habitable zone. This finding is very exciting for the scientist especially because it boosts up more more research because they believe there are a numbers more habitable planets, potentially even closer than Proxima b.
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Image of exoplanet Proxima b or Proxima Centauri b
Isn’t it amazing to know that there are probably other lives out there other than us in our stellar neighborhood? There are more things we don’t know about than those we do. Our universe is too vastly scary to me but somehow I am intrigued to know more and more.

READ MORE ABOUT PROXIMA B HERE


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Chaotic Earth

Posted on March 31, 2017 by jakesindelar

Earth’s violent past: GIF

From Earth’s birth 4.6 billion years ago, it has been through some violent trauma. From worldwide ice ages and raging fire storms, it is a wonder that we made it here in one piece….or most of us. Asteroids regularly come in contact with Earth, wreaking havoc on the surface below. These meteors interfere with nature’s evolutionary course and artificially choose which species are most “fit” for their environment. A meteor may have given humanity our big break, allowing us to evolve into a more intelligent species. Had this mass extinction never occurred, dinosaurs would likely still be roaming the Earth today.

An alternate theory of the mass extinction

Current scientists believe that a massive asteroid struck Earth 65 million years ago. The meteor came in at an angle, raining fire across the continents. After striking the Earth, a massive tsunami struck most of the land-dwellers down. The dust that was spread throughout the atmosphere had the deadliest effects: global winter. Those species that didn’t suffocate in the smoke or freeze in the suddenly cool climate, starved, as photosynthesis halted for a year. This mass extinction killed 99% of the creatures living on Earth and eradicated 3 quarters of the terrestrial species. Those that could burrow deep in the group or swim to the bottom of the ocean stood a chance at survival, everyone else perished. The most successful creatures to survive this extinction were small mammals who hid under the earth and stored food before the disaster. Now, birds are the only memories of the giants that once ruled the Earth.

Source: Cosmic Perspective Chapter 12


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Life On Other Worlds

Posted on March 31, 2017 by jakesindelar
Image result for exoplanets

An artist’s rendition of a habitable world: IAU

The search for exoplanets is one of the most exciting projects in science today. The possibility of earth-like worlds harboring intelligent life is what has electrified most science fiction geeks. With enough funding, the possibilities are endless! Our ability to detect these elusive worlds has improved since our first discovery two decades ago. In late ’95, astrophysicists found a planet the size of Jupiter orbiting a star elsewhere in the Milky Way. It wasn’t long before astronomers rushed to the occasion and began vigorously scouring the skies for these fascinating worlds.

The new field of astrobiology has been born out of the exoplanet search. If we find new worlds, we must find out if there is a possibility of life on its surface. So far, astrobiologists have gotten their hands dirty by analyzing ancient meteorites and examining extremophiles, organisms that thrive in some of the most extreme conditions from volcanoes to the depths of the ocean floor.

The most popular method of finding these extrasolar planets is the transit method. This technique uses the spectrum of a star and detects a planet if a portion of its light decreases temporarily in a pattern. The planets are going through its elliptical orbit and with each cycle, it passes around its Sun, blocking part of the light from our view. It is exciting that we are living in a time where if life exists out there, we will most likely know soon!

Here is an informative exoplanet video!

Sources: Cosmic Perspective: Chapter 13, nature.com


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The Terrestrial Worlds

Posted on March 31, 2017 by jakesindelar

Source: Here

The planets of the Solar System dramatically vary from massive gaseous, ringed giants to
miniature rocky terrestrials. The celestial bodies are also at such great distances that no map of our Solar System can truly illustrate both the distances and relative sizes to scale. The terrestrial planets are relatively similar in size and composition, but interestingly, their atmospheres could not be more different.

Cool Solar System Scale Video!

Atmospheres are vital to the survival of life,  though they do not normally extend very far past the planet’s surface. Our atmosphere is about as thick to the Earth and the thickness of a piece of paper is to a globe.

Mercury, the smallest and lightest planet and nearest to the Sun, has virtually no atmosphere. This means that the stars would be visible through the daytime. With a lack of a serious atmosphere, Mercury is unable to retain its heat, despite its close proximity to the Sun. Unfortunately for Mercury, the planet is vulnerable to heavy cratering and has the appearance of our Moon. Mercury’s days are longer than its year, leading to extreme temperature fluctuations.

Venus is the next terrestrial world, similar in size to the Earth. It is one of the brightest objects in our Solar System, known as the morning and evening star. Its atmospheric pressure is 92 times higher than Earth and Venus’s hellish Greenhouse effect has created a wasteland. Despite not being the closest planet to the Sun, Venus has heated itself beyond belief. Venus serves as a stark reminder of the destructive power of the greenhouse effect.

Our home, Earth, is the largest terrestrial planet and has a powerful ozone layer to protect us from dangerous light and has temperatures that tolerate life and allow for liquid water. Its combination of water and CO2 provide a greenhouse effect that is just strong enough to keep our planet warm. Unlike the other terrestrials, the Earth’s surface is rich and diverse. It also has a Moon that is oddly large in comparison to the size of the Earth.

Mars is the second smallest planet and fourth terrestrial from the Sun. Its mass is just one-tenth of Earth’s. Its atmosphere is incredibly thin and exposes the planet to harmful radiation. It has polar ice caps at its poles, made from frozen CO2 and is the only world that might have once supported life. Its surface also experiences violent dust storms that can last for months, blocking the planet’s surface from view.

Examining the differences between the terrestrial planets’ atmospheres is just another reason why we are so lucky living on Earth. A perfect balance between the scorching Venus atmosphere and Mercury’s lack of one, the Earth provides the perfect home for life.

Sources: Cosmic Perspective: (195-198, 271-272), Planetary Atmospheres Article


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The Voyagers

Posted on March 31, 2017 by Afi Mohd Sayuti

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Image of The Voyager 2 

The study of astronomy has been made easier and easier day by day because of the powerful man-made space probes.  Two spacecrafts that I find very interesting is from the Voyager Program, called Voyager 2. Voyager 1 and Voyager 2 were two of the human-made most distant objects, other than Pioneer 10 and Pioneer 11.

But why am I more interested in Voyager 2 than Voyager 1? Well, contrary to what they were named of, Voyager 2 was the first one to be launched in 1977 to further the studies of our vast Solar System. Voyager 2 was launched on 20th August (it’s my birthday yay!) weighing about 773 kilograms where 150 kilograms are scientific instruments. Voyager 1 was named so even though it was launched 16 days after its twin is because its trajectory follows a quicker path to Saturn and Jupiter. So, Voyager 1 reached Saturn and Jupiter before Voyager 2 did, hence the name! Despite that it is 4 months to late to reach planets Saturn and Jupiter, Voyager 2 was considered more special (at least by me haha). This is because it is the only and only spacecraft that has ever reached Uranus and Neptune! Up until today, this spacecraft has served us a vast range of knowledges about the outer space that we could not be thankful enough.

Here are some of the images captured by the Voyagers

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One of the 33,000 pictures of Jupiter taken by the Voyagers
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Saturn in ultraviolet, violet and green filters captured by Voyager 2.

Read more about Saturn findings here and Jupiter findings here by the Voyagers.


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Dating Everyday Objects?

Posted on March 30, 2017 by ritam216

Radiometric dating is generally used for items in our solar system that exponentially older than humans. The composition of an object is evaluated for its ratio of parent and daughter isotopes. This ratio will provide a good estimate of an object’s age if we know the corresponding half-life. But can we use this same process to figure out the ages of items on a much smaller scale? Do isotopes exist, that are found naturally, that would be able to determine the ages of items that could otherwise be calculated through observation across our lifetime?

This image shows a visual representation of what the half-life of an element means and looks like across the parent isotope’s lifetime.

After browsing through several sources, it seemed that this Wikipedia page had the most plentiful information about a variety of isotopes. While many of the synthetic elements (95-118) have half-lives within my timescale of interest, they do not occur naturally, so I did not heavily investigate them. After spending some time with an abundance of tabs open on my browser comparing a handful of isotopes from familiar elements, I came to a few conclusions. There aren’t a whole lot of natural isotopes that would be useful for short-term radiometric dating. In general, there are very few isotopes that have half-lives that are 0-100 years. Furthermore, most of these isotopes only occur within artificial settings.
I’m a little disappointed by these findings, but I suppose it’s for the best that we don’t have highly unstable isotopes occurring in abundance. Likewise, the good news is that we always have the alternative methods for determining the ages of things that exist within the span of our lifetimes.


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Earth vs. Theia! First and Last Round!

Posted on March 30, 2017 by nazshaiful

I have a thing for stuff that is outrageous, different and intriguing. Greek Gods, bizarre happenings in space, and archaic events? Yes, please! So, I just recently learned about how Moon was the result of an ancient collision between old Earth (or some people call it Gaia) and another theoretical planet named Theia 4.5 billion years ago. Also known as The Big Splash or The Theia Impact, the historical collision was believed to be the origin of Moon.

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Simulation of how Theia (black), orbiting in Langrange point L4 before it collided head-on with Earth (blue) before the remnants condensed into Moon (gray) SOURCE

Theia, a hypothesized planetary-mass planet was said to be the size of Mars. In the early Solar System, Theia was an asteroid, also called Earth trojan, orbiting in Langrange points L4 and L5. Based on the investigation, astronomers think that the collision happened before our Solar System was formed, approximately 100 million years before. It was said that Theia had struck a nearly full formed Earth at a 45 degrees angle with a strapping side swipe, with an impactor velocity of 4m/s which is quite relatively slow. There is also a hypothesis which says that the impact initiated a vigorous mixing which made Theia’s iron core to mix into Earth’s core and Theia’s mantle assembled into Earth’s.

Due to the impact, shock wave spread out and materials from both planets were jumbled together and discharged out into the orbit. The materials, consisting of rocks and minerals orbit around the Earth for some time before they fused together, forming the Moon we know today.

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The artist’s depiction of the collision. SOURCE

One of the evidences which support this event was the similarities in the oxygen isotopes of both Earth and Moon. Edward Young, a geochemistry professor at UCLA and also the one who lead the study, found that the oxygen isotopes that were found on Earth and Moon are indistinguishable. This furthermore support the argument that Theia had thoroughy mixed into Earth before their debris coalesced to form Moon. Further read can be done here.

More investigations are still being made, and many hypothesis are still being voiced out by astronomers. The verdict? I myself am still not sure. Whatever it is, I believe that everything has their own existence.

 

 

 

 


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Planet Past Pluto?

Posted on March 30, 2017 by abbeyroth

Orbits_1280_PlanetX2

In the image above, the red oval represents the suggested path of an elusive planet called Planet X. Astronomers have been observing the orbits of objects in our Solar System and have decided there’s a strong possibility a ninth planet, almost the size of Neptune, is orbiting our Sun. Although Planet X has yet to be detected with any telescope, astronomers believe its orbit interacts with the orbits of other icy objects in the far reaches of our Solar System. In fact, there is only a 1 in 15,000 chance that the orbits of these icy objects would line up the way they do without the existence of a ninth planet. Planet X would be orbiting anywhere from 600 to 1,200 AU in its very elliptical orbit, and would take about 15,000 years to make one trip around the Sun. Astronomers are working on detecting Planet X with the help of the Keck and Subaru telescopes in Hawaii and are confident they will be able to detect it within the next five years or so.

 

SCIENCE Article


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Mission to Europa

Posted on March 29, 2017 by abbeyroth

space_advocates_europa1

NASA has plans to launch a satellite headed to Europa! The Europa Clipper is planned to complete 45 flybys around Europa at varying heights above the surface (16 miles to 1,700 miles) and collect crucial data about Jupiter’s large moon. Scientists are hoping to gather information about the planet’s icy crust, its depth, and what lies underneath; astronomers are fairly certain that an ocean exists under the thick ice. Nine scientific instruments will be aboard this satellite and will measure the planet’s magnetic field (to determine size and salinity of the underground ocean), temperature, and composition. These characteristics will hopefully help astronomers and scientists weigh the possibility of life existing somewhere on Europa. These findings will also help astronomers make the decision of what comes next? If the satellite discovers a habitat conducive to living organisms, NASA may want to start planning for another trip to Europa; this time, to drill into the icy surface and make observations about the watery depths.

NASA Europa Clipper Mission

Europa Video


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Diamond Rain?

Posted on March 29, 2017 by abbeyroth

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Scientists are exploring the idea that diamonds rain down from the skies on Saturn and Jupiter. Methane exists in abundance in the atmospheres of these planets, and lighting storms turn this methane into soot (which is pure carbon). As the soot falls toward the planet’s surface, it hardens under intense pressures and forms small diamonds about one centimeter wide. These are not cut diamonds, of course, so the sky wouldn’t be glimmering like in the photo above, but the size of the stones are still impressive. Dr. Kevin Baines of the University of Wisconsin-Madison theorizes that about 1,000 tons of diamonds are rained down onto the surface of Saturn every year. As the diamonds fall from the atmosphere (over two and a half spans of the Earth), the diamonds are exposed to such high temperatures and pressures, they turn to liquid carbon. In contrast, other planets that allow for the possibility of diamond rain like Uranus, would be able to maintain the diamonds in solid form; their surface temperatures are much lower than Saturn and Jupiter’s. BBC “Diamond Rain Falls on Saturn and Jupiter”


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