Today’s partial Solar eclipse is off to a great start here in Witney, where the cloud cover is working as a perfect solar filter.
The eclipse culminated here as a smiling, Cheshire cat-style grin 🙂
Line 1. Let’s start with ‘typical’ humans. The average human adult male is 1.75 metres tall – that’s 3.83 cubits or 5.74 feet. The average female is 1.62 metres – that’s 5.4 light-nanoseconds or 0.008 furlongs.
You live on Earth (Sol d, perhaps?). This is an Earth-like planet in a Sun-like star system. The third planet of eight in a rich system, including a least one planet populated entirely by robots (Mars, perhaps?). Earth is 12,742 km in diameter and thus has a circumference of 40,000 km or roughly 25,000 miles. Humans live in a thin layer (~20km) around the surface called the troposphere. If the Earth was a beach ball then all life on Earth exists within just 1mm around the surface.
Through many years of international effort we have managed to keep a ‘space’ station in orbit – just above this troposphere – 1cm above the beach ball. But not high enough up that it can totally avoid the atmosphere – the ISS has to constantly boost itself back up because of air drag. We have sent just 24 people out into deep space, beyond the Earth’s atmosphere. All of then visited the Moon and the last ones returned in 1972: 42 years ago. They were all men, all white, and all American. We could do it again, we could do it better – but we chose not do so. (Mostly for political reasons IMHO.)
Those astronauts visited the nearest body in space: the Moon – the second brightest thing in the sky . They were kind enough to return some photos to show us how teeny tiny we are, and how delicate out world really is. The Moon sits about a quarter of a million miles away (384,000 km). You could fit all the Solar System’s other planets in that gap.
But that doesn’t include the Sun – the brightest thing in the sky. The Sun is truly huge. You can fit the Earth inside the Sun a million times. It has more than enough room for all the planets and then some. The Sun itself sits 93 million miles away – which means that light takes 8 minutes to reach us from the Sun. The Sun could have gone out 7.9 minutes ago and you’d only find out… now. Nope: we’re ok. For now.
And yet we have flung robots into space and downloaded the images they have recorded. Sometimes we take extremely long-range selfies of a sort. Images of the Earth, of humanity reduced to a pixel or two. Here’s one from Mars, one from Saturn and one from out near the edge of the Solar System – taken by Voyager. These images collectively earn us the moniker ‘pale blue dot’. Out by Pluto, the Sun itself is has dimmed to look like an other stars. From Saturn, we are just a couple of pixels as seen by the Cassini probe:
And truthfully, the Sun isn’t so special. In fact there are stars which make the Sun look even smaller than the Earth does here. VY Canis Major is staggeringly big – and could encompass the Sun 1,000,000,000 times. That’s a million trillion Earths. Oh and VY Canis Major isn’t even visible to the naked eye because it’s so far away that we can’t detect its photons without aid of telescopes or binoculars.
Which brings us to the Galaxy. The Sun is just one of hundred of billions of stars orbiting around the Milky Way. If the Sun was a blood cell then the Milky Way is the size of Europe. The Milky Way is staggeringly big also staggering diffuse – so much so that if you took two Milky Ways, and hit one with the other, then in all likelihood no two stars would collide. They would pass though each other like smoke.
In fact this will happen. The Andromeda galaxy – which is a lot like the Milky Way – is on a collision course with us. In about 4 billion years it will begin to merge with our galaxy in a spectacular collision. We see these happening elsewhere but the sheer scale of this vision in our own night sky makes me want to get a time machine and jump forward to see it happen. The Earth is unlikely to be affected by this, because of the lack of collisions – however our night sky will be spectacularly altered for hundred of billions of years. Makes you realise how dull it is right now. Just kidding!
But the Milky Way and Andromeda are just two out of hundred of billions of galaxies in the Universe. Gigantic stellar continents floating in a vast, void of almost nothing. Galaxies themselves form structures, and as we have looked deep into the cosmos we have seen one such structure: the Sloan Great Wall. A thick chain of galaxies, loosely bound to each other by gravity, stretching 1.4 billion light years across the Universe and about 1 billion light years from the Milky Way. It’s 1/60 of the Universe across. And yet there are even bigger thing out there.
The largest known structure in the Universe is the Hercules–Corona Borealis Great Wall. At 10 billion light years across, this huge filament of galaxies in 1/10 the size of the observable Universe. It’s 100,000 time the size of the Milky Way, and 70 million trillion times bigger than than the Sun. We don’t have a good picture of it, but we know it’s there. It’s 7,000,000,000,000,000,000,000 times bigger than the Earth, which is very much bigger than you. I refer you to line 1.
Hubot is an open source chatbot created by GitHub. It’s used by various companies, groups, and other techie types, to control systems, gather information, and put moustaches on things – all via chat interfaces. Hubot can be adapted to work via IM, GTalk, Twitter, IRC, and other platforms. ‘Chat Ops‘ is a growing trends, and because it is simple, and quite charming, I think it may stick around.
I’ve just finished an epic few days at the sixth .Astronomy event. This is my own conference series, and I’m gleefully exhausted from several days of talking, making, and hosting my favourite event of the year. More on that in a later post. During the .Astronomy 6 Hack Day (sponsored by GitHub in fact!) I worked on making an astronomical Hubot – which I’ve called ‘botastro‘ in honor of the #dotastro hashtag from .Astronomy itself.
@botastro exists only on Twitter (for now) and to interact you just tweet it. For example if you tweet
then @botastro will reply
You can can send multiple messages to the bot, but I have a growing list of other ideas too. Currently you can say things like:
and asking it to ‘exoplanet me’ gives you an exoplanet from the catalogue (thanks to Dan Foreman-Mackey and Geert Berensten). The results you get when asking it to show you something or tell you about something are sourced from Stuart Lowe‘s lookUP service, and the space gifs come from Giphy.
These may be silly and fun, but more complex actions become possible – especially once I get a bit more used to Coffeescipt, the language this bot is written in.
@botastro is open source (on GitHub, naturally) and I’d love it if people wanted to add functionality. If you want to try, you’ll need to fork the repo, create a new script, and submit a pull request. Hubot is outlined here, and you can look at botastro’s other scripts for examples too.
H₂O might be the most familiar chemical compound on the planet. Many people know that water is H₂O, but most wouldn’t think about what that means in a chemical sense. Water is a remarkable molecule made of two Hydrogen atoms bound to a single Oxygen atom: H, H, and O. Water’s special properties give us life as we know it, and we’re mostly made of it too. It’s less dense as a solid (ice) than as a liquid, which has major consequences for the planet and its climate. Water is also really good at storing heat, and it stays liquid over a wide range of temperatures, also very handy for life as we know it.
In short: water is amazing: but can we destroy it? Yes. With just two regular pencils and a 9V battery, you can actually break water down into it’s Hydrogen and Oxygen components, and watch them boil away as bubbles of gas. This is fundamental chemistry available to anyone at home, with stuff you might have lying around.
You’ll need some salt, a 9V battery, a drinking glass (or other transparent container), two pencils, and some wire. It ’s best to get some cheap cables with crocodile clips (I bought these ones from Amazon), since they make it much easier.
Pour some warm water in the glass and stir in a tablespoon of the salt. You should probably also open a window – or at least don’t do this in a tiny cupboard – a small amount of Chlorine may be produced as you do this experiment; it’s not dangerous as far as I can tell, but best to be safe.
Sharpen both the pencils at both their ends – so that’s four pencil points in all. Connect both nodes of the battery to a different pencil using the crocodile clips.
At this point I suggest you distract yourself by trying to touch the free pencil tips together to make small sparks! The electrons really ‘want’ to make a circuit and can jump across a short air gap, ionising the air and making a crackle and an electrical arc. It’s a 5mm lightning bolt on a pencil tip. But anyway, back to main point of this…
Put the free pencils ends into the water, and don’t let the tips touch. Now for the science! At this point the water becomes part of the circuit. Electrons flow down one pencil, across the water and back into the other pencil. This creates a circuit and electrons flow around it. You’ll know it’s working because this process quickly creates bubbles at the pencil tips in the water. It happens almost instantly.
The energy of the electrons in the circuit is enough to break the water into Hydrogen and Oxygen ions: electrically charged versions of the elements themselves. These ions then flow to the oppositely-charged pencil tip, creating an electric current. This is known as electrolysis.
At the negative pencil tip (the anode) positively charged hydrogen ions (or just protons to some people) meet and form hydrogen gas (H₂) that bubbles to the surface. The positive pencil tip (the cathode) draws the negative Oxygen ions and form O₂. It’s a bit more complex than that, if you’ve been counting electrons, but that’s the overall result. This is electrolysis of water and it’s the world’s primary way of producing Hydrogen – for example for hydrogen fuel cells.
You might be wondering why we need salt. This could be done without salt, but it wold happen more slowly. Can should try it, to prove it to yourself. Salt dissolves into the water creating ions of its own. These flow around the circuit too (creating Sodium and a tiny volume of Chlorine gas) and helps increase the circuit’s overall flow of electrons. You might be able to smell the faint whiff of Chlorine if you do this for long enough.
If you want to take this further, you might think about how to collect the Hydrogen and Oxygen separately – and what you might do with them if you were doing this on an industry scale.
I’ve been called a lot of things but ‘rebel’ hasn’t come up too often. Not that I mind. As part of a Mazda campaign, I’m being highlighted as one of four TED Fellows* who are ‘Mazda Rebels’. The other three are thoroughly impressive and I recommend you take a look. There’s an online vote where the pubic help chose whoever they think the deserves a Mazda grant to help their project.
My video can be found here. It’s lovely and I really enjoyed making it. It nicely describes my work with Zooniverse (special guest starring Brooke Simmons as a Snapshot Serengeti volunteer!) in a fun, accessible way. We had a laugh creating it, and they have kept many of the out-takes in the video, which I rather enjoyed.
If I win the vote then I’ll be using the money to kick-start the Zooniverse’s efforts in disaster relief with a ‘First Responders’ project. Think Milky Way Project but with aerial photos of recent disasters, with volunteers helping locate resources, danger, and people. This is something several of us at Zooniverse HQ are very keen on, and using the power of crowdsourcing in realtime after a disaster makes a lot of sense.
I highly recommend that you take a look at all four videos and vote for your favourite here: https://www.mazdarebels.com/en-gb/content/four-inspiring-ted-fellows-one-mazda-grant/
* Applications are still open to become a 2015 TED Fellow – I can highly recommend it!
I got into a conversation recently about how some astronomical photos can totally change your whole perspective of yourself and your place in the Universe. There’s several images that come to mind right away – here are my own favourites:
1. The Milky Way (from a very dark location)
Seeing the night sky from a dark site is something most people don’t do very often, now that most of us live in cities. The vision of the Milky Way overhead can be startling, and a pair of binoculars make it more so; revealing that its delicate structure is made of millions of stars. This long-exposure photo of the dust lanes in our galaxy  is our first image that can really change your perspective on yourself and your place in the cosmos.
2. Earthshine on a crescent moon
When the Moon is just a thin crescent in the evening sky you can often see the rest of its face, dimly lit, and slightly reddened. This part of the Moon is not being illuminated by the Sun, like the crescent shape itself, but rather by the reflection of light from the Earth where the Sun has not yet gone down over the horizon. You’re seeing other people’s daylight, bounced back at you from around the world .
3. Aurora and lightning from the ISS
Sometimes a change in perspective can be quite literal – as with this video of the Earth seen from the International Space Station. The green structures are aurora- the Northern Lights over Canada in this case. You can also catch the occasional flash of lightning. This time-lapse is haunting and shows you a view you could probably never otherwise see.
4. M31 compared to a full moon
The Andromeda Galaxy is our nearest neighbouring galaxy and can be seen as a faint fuzzy patch in the Northern Sky. What is amazing though, is to realise that in fact it is quite a large object – bigger than our own Moon in our sky. Out eyes just don’t see it very well! Long-exposure images show just how big it really is. Combine this with the fact that it is 200 million light years away  and you begin to realise that the galaxy next door is truly enormous. It’s about the same shape, size, and type as our own Milky Way too. So we will look pretty similar to anyone looking up at the sky from a planet in the Andromeda galaxy.
5. Earth from Saturn (and other places)
There are perhaps no images quite as humbling and shifting as the set of images we would probably call the ‘pale blue dots’. These are the small set of mages of the Earth from far, far away taken by the robots we have sent out into the Solar System. Voyager 1 took one in 1990 from 4.7 billion light years away; Cassini has taken more than one from the Saturnian system (like the one above); a few have been taken from Mars too. All of them show the Earth as just a pixel or so across: encompassing all of humanity, the world, and all life as we know it into a teeny tiny speck against the cosmos.
6. Orion’s Proplyds
These dark blobs hidden within the star-forming complex of the Orion nebula are known as proplyds – or protoplanetary disks. These are embryonic solar systems in the making. Each of these blobs is far larger than our own Solar System (they get smaller as they evolve into spinning orbits) which gives you some idea as to how large the Orion Nebula is in total. We were once shrouded in such a dusty blob ourselves – though long before the Earth formed.
7. The Sloan Great Wall
The largest surveys of galaxies reveal a structure in the Universe so vast that is practically beyond comprehension – but let’s try anyway shall we? The Sloan Great Wall is a filament of galaxies, snaking through the Universe that appear to be physically connected to each other – bound by gravity. The ‘wall’ is 1.38 billion light years across. That’s 1/67th of the observable Universe! When light is emitted on one side it doesn’t reach the other end for 1.38 billion years. It is 1,600 times a long as the distance between the Milky Way and Andromeda. I told you it was hard to imagine.
8. Apollo 8 on Christmas Eve 1968
I thought it would be good to end on something a little closer to home. On December 24th 1968 astronauts Bill Anders, Jim Lovell, and Frank Borman were the voices heard on one of the most-watched television broadcast of all time. As they read passages from the Bible’s Book of Genesis, they broadcast a grainy image of the Earth, as seen from the orbit of the Moon. The world watched themselves from space for the first time, and saw the Earth as a singular marble, set against the deep black of space. The image has since been remastered and still represents an era, and a moment in human history, that many find totally perspective changing. A symbol of a race of beings from a tiny planet, venturing outward to explore space and the worlds beyond their own. Remarkable.
 I recently had my first go at some proper astrophotography from a dark site. My target was the Milky Way and the result was this image of the dust lanes of our galaxy toward the centre of the galaxy. I’m pretty happy with it for a first go.
 This effect can also be seen on other moons around other planets and is generically called ‘Planetshine‘.
 This also serves as a good reminder that there is a part of the Moon we never see – the far side – which is lit by the Sun, but just never seen from Earth.
 That distance gets smaller all the time, and Andromeda will actually collide with us in about 4 billion years.
Warning: 400 words of geekery ahead!
I’ve embarked on an extremely nerdy and wonderful new project: a podcast about rewatching Star Trek. Each week we encourage listeners to watch the same episode we have, and then we’ll dissect and discuss it in deliciously geeky detail.
My cohost in this trek beyond the podcasting frontier is friend and fellow Zooniverse workhorse Grant Miller. Grant sometimes fills in for Chris Lintott on our regular astronomy/science series Recycled Electrons. The other week myself and Grant ended up talking about Star Trek on the show, and a friend remarked that they’d totally listen to us doing a podcast about Star Trek. We’re easily persuaded by flattery and so ‘Star Trek: The Rewatch’ was born.
Our first episode is now up, in which we discuss Encounter at Farpoint – the pilot episode of Star Trek: The Next Generation. We’re hoping that re-watching the show, in order, will make us appreciate it all over again. When you a TV show like this, you get to enjoy each episode in the context of knowing the series and characters really well, and there’s loads of interesting trivia and back-story that is great to explore. Grant and I are both astrophysics PhDs, so we’re also hoping to bring some serious science talk to the show from time to time. We know lots of experts in various fields from around the University (of Oxford) who we hope can pop in and comment every now and then.
Although I’m obviously looking forward to some of my favourite episodes (e.g. Best of Both Worlds, Tapestry) I’m also keen to see how some of the older, or more obscure, episodes hold up to the ensuing decades and changes in the way we enjoy Sci Fi, and TV in general. This is a podcast that I would totally have listened to – so it’s going to be fun to record it. To be honest, even if no one listens, this is going to be awesome! That’s how geeky I am.
If you loved the adventures of Captain Picard and co. – and want to watch them all over again – then join us! Check out startrek.therewatch.com or find us on iTunes. We’re also to be found on Twitter @StarTrekRewatch and on Facebook too.
I spent much of the day working with Edward Gomez (LCOGT) on the littleBits Space Kit. littleBits is a modular system of circuits that let anyone try their hand at something that ordinarily requires a soldering iron. littleBits components may be switches, sensors, servos, or anything really, and they connect magnetically to create deceptively simple circuits that can be quite powerful.
For example you could connect an infrared sensor and an LED to make a device that flashes when you press buttons on your remote. Or you could use a microphone and a digital LCD display to create a sound meter. The littleBits components are sturdy enough to withstand being bashed about a bit, and simple, and large enough, to let you stick on cardboard, homemade figures, or anything else you find around the house. I found out about littleBits when I met their creator, Aya Bdier at TED in March. She is a fellow TED Fellow.
We decided fairly quickly to try and built an exoplanet simulator of some sort and ended up crating the littleBits Exoplanet Detector (and cup orrery). There were two parts to this: a cup-based orrery, and a transit detector.
The cup orrery consisted of a rotating ‘planetary system’ fashioned from a coffee cup mounted on a simple motor component – we only had hack day supplies to play with – and a central LED ‘star’. Some more cups and stirrers were required to scaffold the system into a stable state but it was soon working.
The transit detector used a light-sensor component that read out to both a speaker and a LCD numerical display – Ed refers to this as the laser display board. With a bit of shielding from the buffet’s handy, black, plastic plates the light sensor can easily pick up the LED and you can see the light intensity readout varying as the the paper planet passes in front of the star. It was awesome. We got very excited when it actually worked!
You might think that was geeky enough, but it gets better. I realised I could use my iPhone 5s – which has a high-frame-rate video mode – to record the model working in slow motion and allow us to better see the digital readout. We also realised that the littleBits speaker component can accept an audio jack and so could use the phone to feed in a pure tone, which made it much easier to hear the pulsing dips of the transits.
Finally, we had the idea to record this nice, tonal sound output from the detector and create waveforms to see if we could recover any properties about the exoplanets. And sure enough: we can! We built several different coffee-cup planetary systems (including a big planet, small planet, and twin planets) and their different properties are visible in their waveforms. Ed is planning a more rigorous exploration of this at a later date, but you can see and hear the large cup planet’s waveform below.
So if you want to try something like this, you only need the littleBits Space Kit. You can buy them online and I’d love to see more of these kits, and to see them in schools. I’m now totally addicted to the idea myself too!
Thanks to Arfon for suggesting that we do this Hack Day together; to the NAM 2014 Portsmouth team for being so supportive; and to GitHub for sponsoring it – where else would we have gotten all the cups?!
I was lucky enough to visit Norway last week. I lead a group chasing the aurora (as best you can in cloud!) over the top of Norway from Tromsø to the Russian border – and back again. We were on a boat. Being that my favourite photographer was with me, we got some great shots of icy Norway. We were also lucky enough to have Inger Carter with us, our local Norwegian guide, who is a bit of an aurora-photography expert too. Here are some photos of our trip.
Albert Einstein was ESA’s 4th Automated Transfer Vehicle (ATV). After delivery lots of supplies to the International Space Station if departed last week carrying 1.6 tonnes of waste and garbage. Each ATV mission ends with the spacecraft burning up harmlessly in the atmosphere and this one burnt up on November 2nd at 12:04 GMT over the Pacific. Only this time they snapped a photo as it happened (several photos in fact)!
This image was taken from the ISS when the ATV was 100 km below it and and had begun to burn up as a fireball. You’re seeing 1.6 tonnes of human waste, old clothing, and the kind of stuff you’d find in your own bin or trashcan. Check out the full set of images on ESA’s Flickr page. I wonder if it was visible from the ground?
[Image credit: ESA/NASA]