Tuesday, October 30, 2012

Self Aware Robots Today (Picture of the Day: 10/30/12)

TED. Source

This interesting TED talk comes to us from a fellow named Hod Lipson. This is a man studying how robots can evolve and learn like biological systems. In my opinion, this is one of the most interesting fields right now. The general idea is to see how software in certain circumstances can either learn through trial and error, or evolve through random mutations much like organic organisms. This approach is different than the previous plan of trying to hard code artificial intelligence; we're letting it evolve "naturally" instead of trying to figure everything out ourselves.
As Hod Lipson shows us, this new strategy is coming a long way. Already he's been able to create robots that can learn how to walk and self-replicate. Who knows what the future holds?

Friday, October 26, 2012

SOHO Images

EIT 171

EIT 195

EIT 284

EIT 304. Source

Perhaps you've already figured it out, but these are all pictures of the sun. These up-to-date images come to us courtesy of Solar and Heliospheric Observatory (SOHO), one of the current NASA missions to monitor the sun. Each of these pictures was taken by the Extreme ultraviolet Imaging Telescope (EIT) which takes images of the sun at different wavelengths. These pictures were taken at, in order, 171, 195, 284 and 304 Angstrom wavelengths. Normally these pictures appear black and white right out of the telescope, but these images have been colored in, just like all other astronomical pictures. Each of these pictures shows that the sun is not a boring, featureless ball, but is actually riddled with different temperature regions and high energy plasma arcs.

Sun at visible wavelengths.

In sharp contrast to at non-visible wavelengths, the sun at visible wavelengths is actually quite featureless. This just goes to show what more there is to the universe than what our eyes alone can see.

Tuesday, October 23, 2012

Mammatus Clouds of the Day (Picture of the Day: 10/23/12)

Mammatus clouds over Saskatchewan. Source

This strange image may look like there's something wrong with the camera, but what you're seeing is an actual phenomenon. The bright blotches in the sky come from light reflected by bumps in these mammatus clouds. Normally the bottoms of clouds are flat because of the way they form. Water vapor begins to condense at a very specific temperature that usually corresponds to a very specific altitude. These mammatus clouds, however, have very large and obvious bumps hanging down. Why is this? The easy answer is that we don't really know. There are a lot of theories involving anything from convective currents to ice particles falling. Regardless, they are fascinating to look at.

Sunday, October 21, 2012

Meteor Showers

I have a handy-dandy dictionary on my computer that I often use when reading on the internet. Typing "meteor shower" into this dictionary yields this: a number of meteors that appear to radiate from one point in the sky at a particular date each year, due to the earth's regularly passing through a field of particles at that position in its orbit. Meteor showers are named after the constellation in which the radiant is situated, e.g., the Perseids. This definition is mostly accurate, but it leaves some important things out.

A shot of an Orionid meteor streaking across the sky this weekend. Source

Meteor showers are caused by the collision of the Earth with the field of debris left behind by a comet. As comets travel through their eccentric orbits they slowly break up, leaving behind trails of dust. Most of this dust is ice, but it is peppered with granules of more solid rock. When the Earth's orbit intersects these dust fields, the bits of rock smash into the atmosphere and burn brightly, creating the bright streaks that many call "shooting stars".

 Comet Hyakutake shows off its tail. Source

Astonishingly, the bits of rock that create the brilliant light of a shooting star are usually only about the size of a grain of sand. These bits of dust are moving so fast in relation to the Earth that their impact with the upper atmosphere is explosive. Bigger meteoroids, say around the size of a small pebble, will make brighter streaks that may end in a bright flash. These are known as "fireballs".

Here a fireball is seen during an aurora over Norway. Source

Usually meteor showers are rather slow, with something like 20 to 30 meteors an hour, but sometimes they can produce more than 1,000 meteors an hour. When this happens, they are no longer referred to as "meteor showers", instead their called "meteor outbursts" or "meteor storms". These spectacular events don't happen very often, but we may see one again in 2014. 

Leonid meteor storm. Source

One final interesting fact about meteor showers: they can appear anywhere there is a mostly transparent atmosphere. This means that planets like Mars also have meteor showers. Mars' thin atmosphere doesn't stop it from creating shooting stars when it runs into a comet's tail. The reason for this is fairly simple. On Earth, meteoroids burn up in the very upper atmosphere, where it's still thin, this means that Mars' atmosphere is thick enough to burn up these small particles.

Meteor over Mars. Source

Orionid Meteor Shower (Picture of the Day: 10/21/12)

A shot of an Orionid meteor and the aurora in the skies of Norway. Source

This weekend was a prime opportunity to witness a meteor shower. The Orionid meteor shower peaked early this morning (Sunday) with something like 25 meteors an hour. You have to be patient when watching the night skies, but it pays off. These meteors are bits of debris from Halley's Comet.
I tried, on multiple occasions, to get out and watch this shower, but never managed to do it. Luckily, more spectacular meteor showers are predicted to occur in future years, so I recommend everyone getting out to see those.

Thursday, October 18, 2012

Merging Galaxies (Picture of the Day: 10/18/12)

NGC 2623. Source

This isn't one galaxy, it's two. This object, known as NGC 2623, is a galactic merger. Two massive galaxies got caught in each other's gravitational pulls and are now becoming one. This process looks quite violent when sped up, but any life that may exist within either of those galaxies will probably survive.

Tuesday, October 16, 2012

Earth and Sky (Picture of the Day: 10/16/12)

White Dome Geyser erupting during an aurora. From: Robert Howell

At first glance I thought this picture was some construct of computer graphics, but reportedly it's real. This is a picture of the White Dome Geyser in Yellow Stone National Park. The photographer carefully planned and managed to get a picture of it erupting around midnight during a recent aurora. I just thought it was impressive.

Monday, October 15, 2012

Our Biggest Challenge: Picture of the Day (or Video): 10/15/12

Our Biggest Challenge.

This latest installment in the Symphony of Science is all about climate change. We all have a duty to do what we can to change the world. Only through our combined effort can we really make this planet a better place for the future.

Sunday, October 14, 2012

Black Sun: Picture of the Day 10/14/12

Our sun. Source

This familiar image is actually our sun. It was taken in black and white, focusing on a very specific wavelength of light, and then the picture was inverted and placed on an inverted star field background. Apart from being quite interesting to look at, this picture also highlights the filaments on the solar surface.

Friday, October 12, 2012

Pan-STARRS Sky View (Picture of the Day: 10/12/12)

Pan-STARRS looking towards Sagittarius. Source

This lovely image comes courtesy of Pan-STARRS (the Panoramic Survey Telescope & Rapid Response System), a device intended to search for potentially dangerous asteroids and comets. The image spans 3 degrees of the night sky, equal to almost 6 times the width of the moon. Dust illuminated by starlight is shown in red hues while the light emitted by hydrogen has been colored green. In this one shot alone you can see the Lagoon Nebula (M8), the Trifid Nebula (M20) and NGC 6559. 

Wednesday, October 10, 2012

Picture of the Day: 10/10/12

Nauset Lighthouse on Cape Cod. Source

The lighthouse in this picture is fixed, as you might be able to tell, yet the stars seem to be spinning around in circles. Why is that? Well, the star's positions are fixed in relation to our solar system (they do change a little over time, but barely), it is the Earth's rotation that makes them look like they are rising and falling. This image was taken over a long period of time and shows that rotation.

Tuesday, October 9, 2012

Picture of the Day: 10/9/12

Simeis 147. Source

This supernova remnant, the gaseous and dusty remains of a star, is a long way off, but it's really, really big. Even though Simeis 147 is 3,000 light years away it still takes up nearly 3 degrees of the night sky, that's almost 6 full moons worth. That corresponds to Simeis 147 being 150 light years across. Too bad it's not nearly bright enough to be seen with the naked eye.

Monday, October 8, 2012

Picture of the Day: 10/8/12

Wide shot of an aurora over Utah. Source

More focused version. 

This picture, taken today by Scott Lowther, is of an aurora over Utah. This is fairly spectacular considering how far south it is, but we should be expecting a lot of that in the months to come. I just thought it was cool. Apparently there were also aurorae near Iowa, where I live, but I couldn't find pictures of them.

Sunday, October 7, 2012

Coronal Mass Ejections

The term "coronal mass ejection" (CME) relates to what happens every time the sun throws off a huge ball of plasma. Basically, the surface of the sun is riddled with powerful magnetic lines crisscrossing in an intricate, and very confusing, pattern. Super heated plasma from the sun will flow along these magnetic lines forming arcs large enough to allow several Earths to pass through. On occasion, these magnetic lines will come into contact with each other, or otherwise decide to reorder themselves, and when this happens there is a massive explosion that throws some of that super heated plasma into space. To put it into simpler terms, a CME is a burst of highly charged protons, electrons and some heavier particles that is thrown into space.

The powerful magnetic lines across the surface of the sun are very confusing. Source

Here a long standing magnetic filament explodes, releasing a CME. Source

On occasion these waves of charged particles will come into contact with a planet, at which point they become interplanetary CMEs (ICMEs). When this happens on the Earth, the planets own magnetic field acts like a shield and blocks out most of the powerful blast. Earth's magnetic field isn't a perfect shield, however. Powerful ICMEs can cause geomagnetic storms and will deform the magnetic field. When these ICMEs hit, the charged particles are directed along the magnetic field to the Earth's poles where they interact with the atmosphere, creating beautiful aurorae, one of the most notable being the aurora borealis (Northern Lights). 

Earth's magnetic field is distorted by CMEs. Source

Aurora. Source

Aurora borealis from space. Source

As we move into solar maximum, the high point of solar activity, CMEs will occur more frequently, and the aurorae will get brighter and more fascinating. CMEs can cause damage to electrical equipment if they are powerful enough, so some people worry that we are in danger considering that this solar maximum is supposed to be one of the most powerful to date, but in all likelihood, we'll just have some more pretty lights in the sky.

Now doesn't that just look badass? Source

Picture of the Day: 10/7/12

Aurora over Norway. Source

This picture is of an aurora over Norway. The bright streak visible in the sky is actually what's known as a "fireball". A fireball is just like any other meteor, except it's much brighter and more spectacular. Normally, the shooting stars we see are just specks of dust burning up as they enter the Earth's atmosphere, but fireballs are much larger pebble sized rocks. 

Saturday, October 6, 2012

Picture of the Day (or Video): 10/6/12

The Feynman series part 1

I think the video speaks for itself. There is a beauty to science, it doesn't dry up the wonder of the world, if anything, it only serves to make everything more wonderful. If you liked this, there's more than one part.

Friday, October 5, 2012

Picture of the Day: 10/5/12

The heart of Orion. From NASA

This beautiful picture is the heart of the Orion nebula. The four hot, bright stars at the center are known as "the Trapezium". The beautiful lights from this star forming region are caused by ultraviolet radiation coming from these four stars.

Thursday, October 4, 2012

Picture of the Day: 10/4/12

Black mamba. From Medical Daily

As chance would have it, the deadly venomous black mamba may be the source of the next painkiller. A team of French scientists, led by Sylvie Diochot and Anne Baron, identified two proteins in the snake's venom that act as strong, fast-acting painkillers. Reportedly, these proteins are better painkillers than morphine, and without all the side effects. Just think, soon doctors may prep patients for surgery with chemicals from a snake.

Wednesday, October 3, 2012

Blue Dragon Sea Slug

I know I'm a little late to the game on this one, but I've just recently discovered this tough little sea slug by the name of Glaucus Atlanticus, otherwise known as the blue dragon sea slug.

Glaucus Atlanticus. Source

This particular mollusk usually resides off the coasts of places like South Africa, Australia and Mozambique. A little bag of gas on the underside of the blue dragon causes it to float upside down on the ocean surface, where it hunts most of its food. Though these things normally only grow up to around three centimeters, they are ferocious predators, feeding on things many times their size. They are so awesome that they feed on the deadly Portuguese Man O' War. Normally, a Man O' War is fatally poisonous, but not only is the blue dragon immune to the Man O' War's poison, it actually commandeers that poison for its own use, storing the lethal stuff in the tips of its finger-like appendages.

Note the finger-like appendages. Source

Glaucus feeds on surface dwelling creatures like the Man O' War (left) and velella velella (right). Source(1) Source(2)

There's just something fascinating about these hermaphroditic slugs. For one, they look pretty cool. Their underbellies, which face towards the surface of the ocean, are colored with blue stripes and their backs, which face downward, are silvery, camouflaging them from all sides. What's more, the poison they take from their prey is concentrated in their appendages, making them much more deadly than the infamous Man O' War.
The ocean is filled with bizarre, cool and scary stuff. I think the blue dragon sea slug fits into all those categories.

Picture of the Day: 10/3/12

A filament erupted throwing off a coronal mass ejection. From NASA

This particular picture is from the end of August, but the sun does stuff like it all the time. Here a filament of superheated plasma was being suspended in an enormous arc above the solar surface by the star's ever changing magnetic fields, but then suddenly collapsed, releasing energetic electrons and protons out into space. A lot of electrons and protons.

Tuesday, October 2, 2012

Picture of the Day: 10/2/12

I'm introducing something new to this blog. I'm calling it the "Picture of the Day". Every day (hopefully) I will include some interesting science-y picture and a short explanation. This is just a little something to make the blog more interesting and it will not interfere with regular posts.

Well, here goes!
Evidence of an ancient stream. From NASA

The Curiosity rover recently discovered what appears to be the bank of a dried up stream on the surface of Mars. The circled rock appears to have been worn smooth by water erosion, as do the small pebbles on the stream bed. The overhanging rock looks similar to the erosion of small bodies of water here on Earth.
This isn't the first evidence that Mars was once running with water, but it certainly lends more credence to the notion. Too bad Mars isn't still as wet as it once was.