Indeed, it is important to remember that pleasure boats (like gravity and waves) do not really exist but are instead emergent phenomena that arise from a combination of misplaced desires to spend time in cramped conditions with one’s family, too much money and not enough sense.

Thankfully for Rob, though, there is a hardworking team of scientists in Switzerland that has been given 9 billion dollars of taxpayer money to determine whether or not gravity does exist and how it actually works if it does exist. Gravity is one of those funny things in physics that is so obviously true that a child can explain it to you and yet it’s so complicated that we still don’t entirely know how it works. Einstein tried to find the root cause of gravity in his theories on general relativity but later these theories were shown to be incorrect on a quantum scale thus the birth of quantum relativity and quantum mechanics. Some physicists are very excited about string theory because they believe that it will provide a unified theory that can explain gravity and that’s part of the work that’s going on in the LHC specifically where they are trying to locate the hypothetical “Graviton” particle.

Generally, though, emergent phenomena are everywhere and there are so many of them that we have to give them names otherwise we’d be swamped by so many fundamental particles that our brains would explode. That’s why a collection of atoms is a “molecule” and it’s why specific molecules in large groups create “waves” or “gravity”; without names it would simply be too much of a nightmare to cope with the amount of particles and forces there are. So while the effects of gravity are quite real, gravity in the abstract is very much as intangible as an imaginary boat.

By now you have probably read Stephen Hawking’s incredibly depressing views on what will happen if earth is discovered by alien life, especially since the entirety of modern news media jumped on that story like seagulls on a discarded french fry. Stephen’s views are, of course, made all the more depressing because they make so much sense when considered in conjunction with examples from human history: cultures of oppression and dependence have sprung up nearly every time a primitive society makes contact with a more advanced one. In these situations it is always the primitive society which gets the short end of the stick so Stephen believes that we should be doing all that we can to hide our presence rather than broadcasting a hello message for the entire galaxy to hear.

Unfortunately ever since the radio was invented interstellar broadcasting is exactly what we have been doing; signals from earth have been speeding away to other star systems for years and years so if there are any alien civilizations listening in on this corner of the galaxy there’s a very good chance that they already know about our presence. Then there’s the astronomically ear-splitting screech that our planet produces when solar winds hit the earth’s magnetic field to create radio waves that are 10,000 times more intense than anything we can produce by ourselves. As a planet, then, we are not very good at concealing ourselves.

Our loudness isn’t just annoying to other civilizations, though; plenty of radio astronomers here on earth are extremely annoyed at the huge background of radiation that they have to eliminate in order to hear objects in space. Due to this background noise most radio astronomy telescopes are located far away from civilization in places such as Jicamarca, Peru; Arecibo, Puerto Rico; and Socorro, New Mexico. In fact one of the most popular (if extravagant) proposed locations for a new telescope is the far side of the moon where the telescopes would be able to operate in complete quiet by using the moon as a shield. Such an array would have to be an un-manned station which is not as great a technological leap as you might imagine; we already have observation stations in the antarctic which are unmanned for the majority of the year and of course none of the rovers that have been sent to Mars were manned.

As for extra-terrestrial life, we can be thankful that even if alien life had heard our earliest transmissions and left immediately for a visit to earth it would still take decades upon decades for them to arrive so for now it’s quite safe to keep blasting our music as loud as we want.

-Hugh

First of all it is obviously true that Rob has got the ham, any scientist worth their salt could figure that out in their sleep!

As for your other question space is black because space does not emit light. Allow me to explain:

Imagine that your eyes are like a white canvas on the ground and that light is like paint droplets that fall onto the canvas, all of the paint droplets together make a very nice picture on the canvas and this picture is sent to your brain which interprets the picture as what you ‘see’. Simply put: your eyes catch light and send it to your brain where it is put together to make a picture.

Our sun emits ‘white light’ which means that it is emitting light at every wavelength across the visible spectrum, (different wavelengths are different colours, blue = 475 nano meters), this light gets reflected off of objects and into our eyes where we can put together the picture like on the canvas. When you see something that’s blue what’s actually happening is that every other wavelength of light is being absorbed by the object, (the same way that when you heat something it absorbs the ‘heat rays’), and the blue wavelength is the only one that bounces off into your eyes.

When we see something that is black what we’re really seeing is no light at all; black objects absorb all wavelengths of visible light which basically means that no light is hitting our eyes at all. Perhaps, then, you should imagine your eyes as a black canvas so that in areas where no paint drops are falling the canvas remains black to indicate an absence of light/paint.

So why is space black? Well most of space is actually nothing, just empty nothingness which doesn’t emit any light at all so when you look up and see a black area of space what you’re really ‘seeing’ is that there is no light hitting your eyes and your brain is showing you black instead.

No, this is not the official tumblr blog of the Canadian Space Agency. This is my blog and I work at the space agency on a co-op program, some of my friends from the physics department wanted to hear some of the stories from the CSA as well as what goes on in the aerospace industry from day to day so I created this blog to keep them informed.

The opinions that are presented here are not necessarily those of the CSA itself or any of its employees (besides myself, of course).

If you’re eagerly tuned into aerospace news every day (and lets be honest, who isn’t?) then you’ll already have heard about the Russian cargo ship which failed to dock with the ISS on Friday July 2nd, if you haven’t heard about it then read on because it’s a pretty neat story…

Some background: the Russian cargo ship “Progress” was first built in 1990 and it’s essentially the un-manned version of the extremely successful Soyuz spacecraft built in the late 60s, in fact it even uses the same rockets for propulsion as its crewed cousin. Progress spacecraft used to be used to transport supplies to the Russian space station Mir but now they carry supplies to the ISS and once the space shuttle program ends Progress will be the only contracted rocket to supply the ISS (although it is always possible that NASA will buy some flights from SpaceX’s Falcon 9 once it’s fully operational). Progress spacecraft have a highly distinguished record when it comes to supplying the ISS, in 2003 when the space shuttle fleet was grounded due to the Columbia disaster the Progress craft was the only rocket available to supply the ISS and it has performed admirably in all aspects of its flight since its inception in the 90s.

Well, almost admirably. On May 1st Progress-37 had to be manually driven during the docking procedure when its automatic docking system failed 1km away from the ISS, the override was extremely well done and even set a record for the longest distance that the craft has ever been remotely flown. Last Friday Progress-38 also experienced a failure of the Kurs automatic docking system 28 minutes away from rendezvous with the ISS but this time the manual override system was not configured in time and the space station crew could do nothing but watch helplessly as the automatic abort sequence diverted their re-supply ship away from the ISS. By the time the remote docking system was operational Progress-38 had diverged too far from its flight path for any chance of salvaging the mission that day, instead flight controllers had to go to work to plan a second docking procedure which was successfully executed on Monday morning.

Russian officials are remaining tight-lipped about the source of the error in the Kur docking system but have indicated that the remote docking procedure was unable to be used because of problems in the connection between a video camera used to guide the ship and the astronauts at the space station.

This is the second failure in a row for the Kur docking system, which I imagine must have some feathers ruffled over at the Russian Federal Space Agency not to mention the ISS. As if the ordinary perils of life as an astronaut weren’t bad enough imagine sitting in a small space station from which there is no escape watching helplessly as the ship that is supposed to be carrying your food drifts slowly further and further away all the while knowing that it will be at least 48 hours before it is possible to attempt another rendezvous.

Obviously the ISS has reserve stocks of food and rocket fuel (another vital bit of cargo being carried by Progress) but that does not make the situation any less tense for the 6 inhabitants of the space station wondering exactly how long they have before they run out of food, it’s pretty amazing that they are able to hold themselves together so well under such circumstances.

-Hugh

In case any members of the RFSA are reading… Привет! Please bear in mind that the views expressed in this post and this blog are absolutely not the views of the Canadian Space Agency or any of its affiliates or employees apart from myself, obviously.

First of all I apologize for the delays.

Secondly I have a question for you, what is the difference between a supernova and a nova? If you know the answer and didn’t have to use the internet to do so then you should probably be doing my job, if you don’t know the answer read on.

Obviously you are aware that a supernova is the result of the death of a large star, this fact is pretty ubiquitous in science fiction nowadays; as I previously mentioned a star grows and shrinks according to the pressure generated at the core and the intense gravitational potential created by the mass of the star. The expansion/shrinking period in a stars life lasts for millions and millions of years but eventually the star runs out of the fuel needed to sustain the fusion reaction at the core which is producing the pressure that keeps gravity at bay. With no outward pressure to sustain its shape the star will rapidly collapse, this causes a huge amount of energy (the gravitational potential of the entire body of the star) to be transferred to all of the gas in the star as kinetic and thermal energy just like an explosion. The result of this transfer of energy creates a vast, hot explosion known as the supernova which pushes the gas and other molecules out in front of it to create the ‘planetary nebula’.

So supernovas are pretty sweet, but what is a regular nova?

To understand a regular nova you have to be aware of another ubiquitous astonomy concept: the binary star system. Most binary systems consist of one ‘regular’ star and one white dwarf and if the stars are close enough to each other then the more massive star can actually ‘eat’ the other star by using its more intense gravitational pull to suck matter away from the surface of the lighter star. Usually it is the white dwarf star eating the more gaseous star so all the hydrogen from the large star forms an accretion disk around the white dwarf, packing in and packing in as more and more gas is piled around the white dwarf. As gas gets added to the disk the pressure at the surface of the white dwarf gets greater and greater, at some point this pressure and the temperature from the dwarf star will ignite a hydrogen fusion reaction at the base of the accretion disk. When the fusion reaction is activated it causes a chain reaction with the rest of the envelope and the resulting energy is so great that the accretion disk becomes an expanding dust cloud just like the planetary nebula, we call this explosion a nova.

Once this dust cloud has disappeared (this can take months to years) there is no longer any hydrogen around the white dwarf and the accretion disk begins to re-form as the dwarf star continues to ‘eat’ its partner. This process will happen continuously until the lighter star undergoes a supernova or the dwarf eats enough hydrogen for the lighter star to simply fizzle out and die.

Isn’t the universe awesome?

Personally I like to imagine the entire process as being somewhat similar to the way students let dishes pile up in the sink until someone gets fed up and has to clean them all, eliminating the problem until the next pile-up.

-Hugh

So a while ago I made a thoughtful and well written pair of posts about what it is exactly that I do (Nobody tosses a dwarf and Supersonic neutronic) and while you probably read the posts and became slightly jealous of my life you probably also asked yourself the very pertinent question “Why the hell do we need to know that?” Thankfully none of you have actually asked me that question so the only person impatiently tapping their foot and waiting for an adequate response is my dad who finally received one yesterday.

If you remember back to my post about how stars oscillate in different modes and methods you’ll recall that I only really talked about radial and p-mode oscillations but I mentioned that there are other ways in which stars variate and that our own star has thousands of different modes that we’ve studied in great detail. One way that the sun variates is the periodic creation and destruction of sunspots, a term that everyone has heard but no one can really adequately describe. Basically a sunspot is a huge knot of magnetic energy that rises to the surface of the sun, its magnetic field is pointing directly away from the surface of the sun and, like an iceberg, a large portion of it is hidden below the surface.

Now recall that since a star is a large body of gas it must have internal convection, hot gas from the bottom of the star must want to rise up to the surface, this creates ‘conveyor belts’ at the surface where the cooler gas sinks, becomes warmed and rises again to the surface. When a sunspot is on the surface, however, the intense magnetism suspends convection in that area and allows the gas to cool resulting in the dark ‘blotches’ we call sunspots. Eventually the relentless pushing and shoving caused by convection will weaken the field of the sunspot and it will be carried away by the ‘conveyor belt’ down closer to the star’s core where the intense magnetism revitalizes the sunspot before it is once again carried to the surface.

This entire cycle takes about 40-50 years and the advent of a large sunspot or group of sunspots always results in what scientists call ‘solar maxima’, a name that’s not quite as catchy (or scary) as the name dreamed up by the Telegraph’s mentally deficient science division. Solar maxima are associated with intense bursts of radiation from the sun that can play havoc with the earth’s magnetic envelope, this is a problem that has gone largely unnoticed by the inhabitants of our fair planet until now. The last solar maximum was in 1958 when the average supercomputer had less memory than a tamagotchi and only two satellites were in orbit around earth (Sputnik and Explorer 1) which meant that no one really noticed any adverse effects of the solar storm.

Fast forward to 2006 when helioseismologists working at NASA predicted that we will see the next solar maxima in 2011 or 2012 and that it will be ~30-50% more intense than the one in 1958. The question is, what will the solar radiation do to all of our electronics? Today, in 2010, we have over 3000 satellites orbiting the earth and if you’re reading this there’s a pretty good chance that you’re using some sort of machine which does not like being exposed to high levels of magnetic flux. A period of intense solar radiation like the one that is now expected in 2013 would play havoc with our network of GPS, telecommunications and (god forbid) 3G network satellites. Obviously the repercussions are much more serious for those emergency services such as hospitals which use machines that save lives but clearly the damage from an intense period of solar radiation will be an interesting test of our ability to handle an electronic collapse in a society that has become extremely dependent on the ability to view lolcats at any time and in any place.

Anyway, we wouldn’t know about this impending electronic doom if it wasn’t for the hard work of astroseismologists who spent time looking at our own sun to determine exactly what is occurring at the center of the star and how we can predict its behaviour. This is exactly why the hell we need to know more about what’s going on in our universe.

-Hugh

One of the things about my job that I still find hard to wrap around my head is the actual size of the universe, I try to avoid thinking about it because it would seriously disrupt my ability to actually do work if I were conceptualizing the distances involved with each star. In fact, nobody really thinks about how big space is, we just accept that it is big and move on with our lives so I want to share something with you that will you figure out just how big this universe of ours really is.

Let me introduce you to Orbiter, it’s a fairly barebones space flight simulator that will run on your PC allowing you to simulate a huge variety of flightplans including suborbital, Earth to geosynchronous orbit, Earth to ISS, Earth to moon as well as landings. You have the option of flying these plans in a variety of spacecraft including the Atlantis space shuttle — which will be taken off duty in November — a fictional ‘Delta wing’ and any number of user created alternatives all with their own strengths and weaknesses.

Once I got past the control scheme I found Orbiter to be a lot of fun, it opened my eyes to the absolutely colossal distances involved in spaceflight and to the monumental challenge of maintaining an accurate flight plan over said distances. The main problem is that a journey in space is hundreds of thousands of miles long, but you are only able to actively thrust for less than 5% of the flight which means that your initial burn must be nearly 100% accurate in both force, direction (in all three dimensions) and duration — a nearly impossible task.

I challenge you to do the Earth to moon flight in orbiter, or even sit along for the ride using the demo program, it really is amazing just how much more thought and calculation goes into what you probably already consider a pretty difficult task especially when you realize that a mistake means catastrophic failure coupled certain death for the crew. It’s a dangerous business and Orbiter does its best to show you exactly how dangerous it’s definitely a game changing experience.

I’ll leave you with Douglas Adams, he’s better at describing space than I am: “Space is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the drug store, but that’s just peanuts to space. ”

-Hugh

OK so last post I talked about what we can do to optimize the light and soil conditions of the plants that we’re growing, but that still leaves two ingredients for plant growth unaccounted for and since they’re fairly brief they’re the perfect subject for a post that is now two days late.

Obviously changing the water conditions is simply a matter of figuring out what are the best vitamins and minerals to add to the water, this is simple trial and error science and unless you grow vegetables for county fair competitions you probably won’t find it too interesting. 

What is much more interesting is the effects of changing the pressure and the makeup of the surrounding atmosphere; plants require the presence of carbon dioxide to perform photosynthesis and it turns out that there is in fact an optimum mix of gases for plants that results in maximum growth but this is rarely cost effective here on earth. Plants have also been shown to respond well to pressure becoming more robust and also more likely to survive as a seed, however even with all these benefits it is still not financially feasible to grow plants in a hyperbaric artificial atmosphere on earth.

On the other hand, greenhouses in space must already be airtight and have a pressure control system in place meaning that we can use the advantages of atmospheric optimization to great effect when growing plants in space. Today I was chatting with a guy involved with the arctic greenhouse project at the CSA, he told me that even though they’re able to control all of the other aspects of the plant growth their greenhouse can’t support atmospheric control since it would be a huge drain on the power supply. However, he still thinks that atmospheric control will be a big part of any greenhouse that would operate in space especially since all of the required equipment comes included with the facility.

As for when we’ll actually see greenhouses in space it is usually pretty difficult to get predictions out of employees at the space agency but the general consensus is that if the 2020 moon-base mission proceeds as planned then we should get the opportunity to test a facility like our arctic greenhouse on the moon in 10 years, which is a pretty exciting prospect.

-Hugh

One of the partner projects that the CSA is involved with is a simulated Mars environment called the Haughton-Mars project, also known as Mars on earth which develops and tests new strategies and technologies for Mars exploration and habitation. One of these projects is actually a greenhouse in the arctic which is powered only by solar and wind energy and is controlled remotely from the CSA so that seeding and feeding the plants doesn’t need to be done by hand, in fact the greenhouse is only occupied by humans for 3 weeks out of the entire year when we do repairs and add new equipment.

The equipment there is much more interesting than you would think, I recently got the opportunity to look at one of the new cameras that will be sent up (to help monitor the plants) as well as the new wind turbines but I want to start with telling you about the technology that’s already in place to grow the plants. As every 6 year old can tell you, plants need four things to grow: Water, air, soil and sunlight (shout out to Sophie who yelled “What about love?” when asked that question) but we wanted to know if these are the optimal conditions for growth or just the minimal ones so we set out to improve the process of growing plants.

We started with sunlight, when the sun shines on a plant it’s bombarding it with all sorts of radiation including infra-red, ultra-violet and all of the visible colours at once but is that really necessary? Do plants actually use all these different wavelengths in photosynthesis? It turns out that they don’t, in fact the only ones that really matter are the red and violet wavelengths of visible light so by lighting the greenhouse in an eerie purple glow we can optimize the amount of plant growth per Watt of power used to grow them, a very important consideration when all of your energy has to be derived from solar and wind power. We further reduce the power consumption by using thousands of LED lights to illuminate the plants rather than incandescent or fluorescent light bulbs that would need to be changed.

Then we moved onto soil, obviously if we are starting a greenhouse in outer space we will need soil in which to grow the plants but carting tons of the earth into space is very wasteful so we set out to find if we could make artificial soil that is as good, or better than dirt. By manufacturing soil out of interwoven polymer fibres and using water with added nutrients we could vastly decrease the amount of mass required to house a plant in space and since weight is money in the space business this became an incredibly important task that was met with success a few years ago. From now on plants that grow in space will be rooted in a green, mushy soil analogue that was developed and tested at the CSA, this is also the type of soil that is used in the greenhouse at the Mars on earth simulation environment.

Obviously space greenhouses will be enormously important for any semi-permanent or permanent space or extra-planetary installations so breakthroughs like those in the properties of light and soil needed to grow plants at optimum levels will be critical to the success of future missions. This research is also interesting because while it makes sense that there should be optimum growing conditions for plants no one had bothered to actually alter the ‘known ingredients’ to try and improve the growing process until now.

-Hugh