Life explained by a comet

Kathrin Altwegg and her team have discovered the building blocks of life on a comet. This can be evidence for a theory about how life on earth arose.

A comet and his friend

One and a half year ago, space probe Philae landed on a comet. To be specific, comet 67P/Churyumov-Gerasimenko. This was the first time space engineers landed something on a comet. It wasn’t a perfect landing, however. The probe bounced of the comet a few times, because there isn’t much gravity to pull the lander down, since the comet is very small. Fortunately, the engineers managed to secure it, although the lander ended up just behind a mountain, making its solar panels practically useless, because of the shadow. This made sending data to earth very difficult for the probe. But after many struggles, it has made an interesting discovery.

The Lego blocks of life

Philae has found the building blocks of life in the tail of the comet. The lander has found amino acids, that make up proteins, like Lego blocks make up a Lego house, which are essential for life. But also phosphorus, which is a component of, among others, ATP, a chemical which is very important for managing the energy levels in your body. These building blocks alone don’t make life yet, of course. But these amino acids and phosphorus can tell us something about how life on earth arose.

Brought by comets

The panspermia theory is strongly supported by this discovery. This theory states that these building blocks of life were formed in space and after that become part of the nebula around the sun from which earth and the other planets were formed. Later, the amino acids, phosphorus and other chemicals would rain down on the planets, and delivering the building blocks to the planet. Since earth had a good environment for life, so one thing led to another, and life on earth arose. There is, however, no way to know for sure that this is the correct theory. There are many theories about how life arose, both scientific and religious. But this discovery really supports this the panspermia theory.

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Sources:

http://advances.sciencemag.org/lens/advances/2/5/e1600285

https://nl.wikipedia.org/wiki/Philae_(lander)#Verloop_van_de_missie

https://en.wikipedia.org/wiki/Coma_(cometary)

https://en.wikipedia.org/wiki/Panspermia

http://www.space.com/images/i/000/009/378/i02/halleys-comet-1986.jpg?1304371881?interpolation=lanczos-none&downsize=640:*

http://www.scientias.nl/wp-content/uploads/2016/01/philae.jpg

It's cold on Mars

‘These results provide evidence for a recent ice age on Mars.’ say Isaac Smith and his team in this week’s issue of Science. They have discovered this by using radar.

Cold times

Ice ages are periods of time when the climate is exceptionally cold, and because of that, there’s a lot of ice. The last ice age ended 11.700 years ago. Warmer periods of time separate one ice age from another. We currently live in one of those warmer periods and the next ice age probably starts in around 50.000 years. We don’t really know yet how ice ages exactly happen. But we know it can be caused by changes in the earth orbit, which causes the earth to get less light, so less warmth. So it gets colder. An ice age can also be caused by the sun. If the sun is less active for a while, earth also gets colder. Another major factor is the concentration of carbon dioxide and methane in the atmosphere. More of these gasses create higher temperatures on earth. Anyway, ice ages are also a thing on Mars.

Give those little green men a coat!

Isaac Smith and his team have discovered with radar techniques evidence for dramatic changes in Mars’ climate. They have found evidence of ice growing in retreating, in the same way you can also see this on earth; small walls made of dirt that was pushed forward by the ice. They have also discovered that the amount of ice around the north pole of Mars has grown with 87.000 cubic kilometres in the last 370.000 years, which is enough ice to cover the whole planet with a sixty-centimetre-thick layer of ice. Isaac Smith and his team were further convinced by the facts that Mars shares a lot of earth’s traits that cause ice ages. Mars orbits around the same sun as earth, of course, which is one thing that causes ice ages on both planets, but Mars also sometimes changes its orbit, like earth. The changes in the orbit of Mars are even bigger, since the planet doesn’t have a big moon, like earth does, to keep the planet in check.

We can use it here too!

With this discovery, we’ve come to know a lot more about how ice ages on Mars work. Which makes it easier to predict the next one. It also gives us more insight in the sun’s influence on ice ages, since we can observe a planet reacting to the sun, but without many earth’s traits. This new knowledge about the sun can help us in predicting our next ice age. And even in how the greenhouse effect is influencing ice ages.

Click here to read more astronomy posts.

Sources:

https://en.wikipedia.org/wiki/Ice_age#Causes_of_ice_ages

https://en.wikipedia.org/wiki/Ice_age

https://en.wikipedia.org/wiki/Water_on_Mars#Ice_ages

https://en.wikipedia.org/wiki/Milankovitch_cycles

http://science.sciencemag.org/content/352/6289/1075

http://sci-hub.bz/10.1126/science.aad6968

http://www.universetoday.com/wp-content/uploads/2010/05/full_cap_along_chasma_v004.jpg

http://www8.gmanews.tv/webpics/v3/2012/06/diego%20manny%20and%20sid.jpg

Colouring numbers takes up 200 terabytes

Mathematical proofs can be simple or extremely difficult. But they’ve got one thing in common; they are at least a little elegant. Or just consist of 200 terabytes of data.

The computer that did the calculations

Blow up that computer

Two hundred terabytes look like a ridiculous amount of data, and it is. It is enough to fill the hard drives of 441 laptops and the compressed version of the data only takes already 30.000 hours to download, that’s about three and a half years. The supercomputer that ran the calculations needed 2 days, with eight hundred processors running at the same time. Nobody is, of course, going to read the proof, since that is impossible. This gigantic thing also has the world record. The proof took it from another mathematical proof that was ‘just’ thirteen gigabytes big.

The first 7824 numbers with their valid colourings, 
the white squares can be either colour

Checking everything                 

But for what could you possibly need so much data? Well, the problem is called the Boolean Pythagorean triples problem. It asks the question if it’s possible to give each number a colour; red or blue, in such a way that there aren’t three numbers that fit into Pythagoras’ equation; a²+b²=c². So when 3 and 5 are blue, 4 has to be red, because 3²+4²=5²=9+16=25. As it turns out, to the number 7824, numbers can be coloured in a ‘valid’ way, but after 7824, not anymore. Up to 7824, there are 10^2,300 possible colour combinations, that's a 1 with 2300 zeroes. Fortunately, Oliver Kullmann and Victor Marek, the mathematician who found the proof, could slim the amount of combinations the supercomputer had to check to just under a trillion.

Where does maths end?

After this proof, a new question arose. Is this really still maths? A lot of mathematicians think otherwise. Because nobody knows why it’s possible to create double-coloured triplets under 7824, but not above. Nor does anyone know what’s special about the number 7825 that it ruins everything. Terence Tao proved the former world record problem, which needed thirteen gigabytes of data to proof, in the ‘old-fashioned’ way, so by reasoning and thinking logically, a year after the computer proved it. Many mathematicians consider that a much more satisfying way and thus the search for the proof of the Boolean Pythagorean triples problem isn’t over yet.

Click here to read more about mathmatics.

Sources:

http://www.nature.com/news/two-hundred-terabyte-maths-proof-is-largest-ever-1.19990?WT.mc_id=SFB_NNEWS_1508_RHBox

https://nl.wikipedia.org/wiki/Terabyte

https://arxiv.org/abs/1605.00723