Gravity in HD!

Check out this sweet, new, glorious map of the Earth!:



Yes, that is correct, you are seeing GRAVITY! When I go to explain my PhD to people, it usually results in them just saying 'So you're trying to find gravity, right?' Well, sort of. But in a wavy, gravy sort of form. This GOCE satellite from the European Space Agency has mapped out the gravitational field of the Earth. This is a little tricky of a map to figure out, especially as there are positive values on the scale. This does NOT mean that when you go to Papua New Guinea, this happens (copyright Bill Watterson):



Instead, the way they describe it on the satellite homepage is that GOCE acts like a spirit level, you know, those ones you have in your house that you played with as a kid to watch bubbles float around? You didn't do that? Oh, okay. Anyway, I am sure you have seen or used these before. The last time I used one properly was trying to install a dishwasher at my ex-boyfriend's house. Try installing a dishwasher without one. Just try it. And then... put it on SUPERWASH and see how many dishes you can break. I bet it makes one hell of a racket. Probably more impressive than my washing machine on hi-spin. Sounds like a rocket engine taking off.
Anecdotes aside, you know what I am talking about. This thing:


This satellite is basically a giant one of these. They have sensitive balls (tee hee) along the satellite that respond to gravitational pull, marking high points and low points. The satellite apparently was supersensitive to any moving parts, so the whole thing is a measuring device. The balls in the machine had to be in effective free-fall to get the readings as well, which is obtained by orbiting Earth (think about it... throw a ball really fast, straight away from you, now since the Earth curves, the ball falls to the ground like normal, but then the ground has fallen away so the ball just keeps falling as it keeps moving horizontally at that speed...crazy, I know) So...yeah, that is how this works.

I am not quite sure of the scientific uses for this. They say that it will be useful information for lots of geological sciences, which I can sort of see, precision is always nice. Plus, this epic map was only two months worth of data, so it is pretty impressive in it's efficiency. They also use the age-old academic reasoning that lots of people in the *ahem* gravitational world use and that is "but it's the TECHNOLOGY! Look at all the cool, supersensitive technology we have developed!" This is valid and widely used reasoning for high-precision science that may not have super-exciting applications just yet. Seriously, you never know when you will need the technology or when the data will be applicable. Pretty picture though, right? Yay, gravity.

Edit: As was pointed out by my esteemed friend, DAstronomer, where the bloody hell are the units on that thing? I assumed the 'level' plot was just a scaled factor, made-up unit thingy. Okay, but seriously, latitude and longitude people! Maybe geophysicists have their own secret unit language.

Lutitia: BIRTH SURVIVOR?

The European Space Agency has revealed images from their Rosetta mission of Asteroid Lutitia. Badass. They got as close as 3162 km, which is just under 2000 miles, which thanks to The Pretenders, we know is very far in the snow, where he's gone. The Pretenders aside, this is pretty cool. Here is the image of the asteroid:


There is also a great simulation video at the ESA Rosetta website to watch.

So, what does this all mean? How is this science? What do we learn? Is this just a futile competition between space agencies saying 'My spaceship did cooler things than your spaceship!'? NO! There are many things we can learn, and plus, as is ever the study of space, it is pretty freaking cool. Here, you can see how close they actually get:



This image shows what seems like a landslide. Pretty epic, eh? The camera they used for these pictures has a 60m resolution at it's closest point to the asteroid. This means that if two objects are more than 60m apart, the camera can tell the difference. Kind of when you see a speck of dust and you get really close, but it turns out it's actually TWO sneaky specks of dust. Do you not spend your time investigating the spectral resolution of dust on your desk? Fine. But, now you will. Or you will at least now see a speck of dust and say 'The resolution of my eyes can only say it is one piece of dust'. You will. Trust me.

The scientists working on this object say that they think it is very old. Seeing all the craters on the surface is a good indication that it has been around for a while. It also does not have the visual characteristics of a young, iron-rich surface which would indicate a different source. This asteroid has been known for a while and has been studied from the ground, but the evidence from these studies has not given a clear picture.

That means that further study of the asteroid can again give clues towards it's source and the evolution of the Solar System. Rosetta has many instruments on it to collect data. One, for example, can collect dust floating around the asteroid and bring it back for study. If that was successful, we will not know until the instrument returns, but it'd be pretty sweet, no?

Rosetta is not done yet, oh no. ESA is going to stretch this instrument like a nice piece of Taffy. This is not even it's main mission, oh no, this was just a pit-stop on the road of scientific discovery. Rosetta is flying on to rendez-vous with the comet Churyumov-Gerasimenko. It is going to fly alongside the comet for a timescale of months, saying 'Please be my friend. Please give me cool things to take home and show my mum! Please? Please? Please?' It is even sending a probe in 2014 (when it meets up) to land on the main part of the comet (the 'nucleus'). We shall all have to wait with baited breath for the next, um, 4-ish years, and see what Rosetta will have to brag about.

Planck sees the microwave sky

As I promised you science-y things, I have decided to begin with the new release of data from the Planck telescope. Here's how this science stuff is going to work. I am picking a topic and going to give you the basic background of it. Sorry, unavoidable, but don't you think it makes the news much cooler? Any background that would be too tedious to go over, I will just put a link to some basic info on it. Feel free to click the link and learn even more! With that all out of the way, it is time for some learning! Here is the press release that this is about. It has appeared in the BBC, NYTimes and countless other sources, so you may have seen it by now. What is it about you may ask? Here we go!

The Planck telescope is a project launched last year by the European Space Agency (ESA). It was launched in May of last year to survey the Cosmic Microwave Background. What is this "Cosmic Microwave Background" you ask? Well, it's nickname is the CMB. You may have heard this before as it is a famous discovery that presents evidence of the Big Bang. It is, in fact, one of the more elegant discoveries of the 20th century. This is a funny story, so pay attention. The CMB was predicted when cosmologists. No, not people who put on makeup, those are cosmetologists, this means people who study the cosmos. Your confusion is acceptable. It's the same derivation: cosmos comes from Greek for 'beauty', or, the antithesis of chaos. Cool, right?

Okay, back to the funny story of the CMB. So, these cosmologists said that if there was a big explosion that started the universe, we should still be able to see it. This may sound weird to you, and it's even weirder to explain. Stick with me. Skip below if you want to remain ignorant of cool science, or you know it already. So, remember that the Big Bang says we all started at one point which rapidly expanded, like an explosion. Given how much stuff had to be in that single point, it must have been very very hot. Same concept as when you rub your hands together quickly and heat begins to build up. Now imagine hundreds of hands all practically in the same place rubbing against each other very fast. Lots of heat, right? Same thing happens when you have lots of particles in a tiny spot, they vibrate against each other and generate heat. Sexy, I know. We have all this heat and then it expands. The 'hands' are not touching each other anymore so the heat begins to cool off, but it does not disappear. Keeping numbers out of the story, it has been a long time since the universe started to expand. That heat, which remains in the universe, has cooled off a lot. It is predicted, given how big the universe is now, that that heat is only about 3 degrees above absolute zero. Early cosmologists gave predictions for what this temperature would be, but had not made an exact estimate.

So, the discovery. Two guys named Arno Penzias and Robert Wilson were working for Bell Labs in New Jersey. They had a supersensitive radio detector to detect extremely faint radio waves. They got rid of all the interference possible, including heat from the receiver itself. There was noise that did not go away; it was everywhere in the sky, at all times of the day and night. Their conclusion? Pigeon poop. In the dignified scientist way, they cleaned off all the excrement, but the noise remained. Penzias heard about research going on at Princeton to discover some radiation left over from the Big Bang that was suspiciously at the same wavelength as the noise they were fighting. Penzias suddenly realised what a big discovery this was and published their discovery jointly in Astrophysical Journals. The Nobel Prize for this discovery was given to them in 1978 for this discovery as it was the first definitive evidence of the Big Bang.

Right, so where are we now? PLANCK. Planck was a cool guy. He will feature this weekend here on this blog, so stay tuned for that. Until then, let us talk about his namesake, the Planck Telescope. The aforementioned heat is not perfectly uniform. Imagine a flat sheet of paper; if you were to zoom in on the paper, it would go from this:



to this:



Well, it is the same thing with the CMB. A non-sensitive telescope, similar to our eye, would just see the CMB as flat and unchanging. If we get a supersensitive telescope, we can measure all the differences. Why is this important you ask? Well, as it is in fact left over from the Big Bang, the tiny differences give hints to the exact structure of that tiny space when the universe began expanding. So, we need these supersensitive telescopes to see the differences. The Planck telescope was preceded by telescopes such as the WMAP and COBE.

Now, the first images have been released by Planck. Here it is, in all it's glory:



This image includes our own galaxy (the stripe across the middle) and some interstellar dust, which you can probably see yourself. They are going to remove the extra stuff, like the galaxy and the dust. The resulting image will look a little like this (courtesy of WMAP):



This image from WMAP shows extremely tiny changes in the CMB. Like looking really close at a piece of paper, this level of sensitivity gives clues towards the beginning of the universe. As science tends to work, we have predictions on how this should look as well as what that means. Bring it on!

Did you have fun? That's science! There will definitely be updates on this, so keep a wary eye out.