Nasa have just released a series of timely photos taken from their Lunar Reconnaissance Orbiter. This orbiter which is gearing up to map the surface of the moon to identify landing sites for future manned missions took some time to snap some images of the landing sites from the last visit we made to our pale dance partner in space.
The orbiter is still not in its final mapping orbit so we can expect future images of these areas to get 2 to 3 times the resolution but even at this early stage its still really exciting to see the marks we left on the moon still there. While Apollo 11 site wins the historically most important site my personal favorite is the snap of the Apollo 14 landing site:
You can actually see the path that Al Shepard and Edgar Mitchell made as they shuffled from the Lunar Module to some of the scientific instruments. Apollo 14 is also my favorite mission for two reasons: as Al Shepard played some golf on the moon and the astronauts took with them a number of seed which where then germinated back on Earth to make Moon Trees (I am a big old sentimental softy at heart) .
While its exciting to have these photos it does highlight a little how much of a shame it is that this is the first time we have seen the site of what is arguably one of humanities greatest accomplishments in over 38 years.
Having just had a “heat wave” here in Scotland we were all reminded that a giant ball of hot gas does indeed grace the sky on a regular basis however two consecutive sunny days in Edinburgh was not the only recent interesting event involving the sun. The Sun, like a middle aged man undergoing a midlife crisis, has donned its leopard print attire once again and after a long absence it has a sunspot again.
The sun is a curios object, despite being the closest astrophysical object to us (apart from the moon and a few other rocks) we still dont know exactly how it ticks . Part of the difficulty is that we can only see a short distance inside the Sun, beyond this the plasma the Sun is made of scatters the light so much it becomes opaque. The most prominent feature on the surface of the sun is normally collections of sun spots: darker patches against the bright background of the solar body. These spots are regions of intense magnetic fields on the surface of the sun and just like a magnet and iron filings the hot plasma traces out the complex magnetic field which can be clearly seen in the close up image below. The magnetic fields in these regions interfere with convection: the proses by which heat makes its way from the depths of the sun to its surface, as a result the sunspots are a cool refreshing 3700 degrees Celsius compared to the surrounding material which is at about 5600 degrees. This comparative frigidity makes the spots dark in appearance
One of the curious aspects of the sun is that it undergoes roughly an 11 year cycle in which the number of sunspots rises and falls. This period is very regular and has been active ever since sunspots have been recorded. Recently we have been in a quite phase of the cycle which was supposed to end late 2007 early 2008 but apart from one small sunspot December last year the sun has remained largely quiet. Its not the first time this has happened as well, records show that around the 1650′s there was a similar (and indeed longer) drought which corresponded to the coldest period of a time know as the “little ice age”. Now before we all get in to a panic and decide on the ridiculous plan of sending some astronauts to bomb the sun back in to activity (they will only go mad and kill each other anyway) I should tell you the good news. A new robust set of sunspots seems to have appears on the sun in the last few days which can be seen in the movie above. Phew, it will be a little longer before we can be sure that a new cycle has stared in earnest but its a good sign. So why was there such a prolonged period of quiet.
Well as I said we dont understand the sun fully because we cant “see” inside it, well that might have been what Terry Pratchet likes to call “a lie to children” (not that I think you are children… unless you are I suppose in which case good for you ). Light is scattered too much by the sun to be of any use but sound waves are free to pass through the sun easily. We see these waves at the surface of the sun as moments of the material there which we can use to infer whats happening deeper in the sun. In what is perhaps the coolest sounding name for a field of Scientists, asteroseismologists study these vibrations on the surface of the sun like regular seismologists study the vibration of the surface of the Earth to figure out what is going on in our own planets core. A group of these scientists at a conference in Colorado recently announced that they had observed and tracked jet streams about 7000km bellow the surface of the sun. These streams appear to form once every 11 years at the suns poles and migrate to the equator, it also appears that when they reach a latitude of 22 degrees they trigger the next cycle of sunspots. The most recent of these jet streams has been moving slower than the pervious, sluggishly working its way down and has only just recently arrived at the magic latitude. This could be an explanation of why we are just seeing sunspots appear now but there is still a lot to learn, how do the jet streams induce sunspots, why was this last one sluggish, how are the jet streams created themselves and perhaps more importantly who came up with the plot to Sunshine and did they know anything about physics, the answers to all of these (apart from the last one ) will have to remain a mystery just now but watch this space for breaking updates as science continues its slow but inevitable march.
The first images from one of Herschel’s cameras are out! While not from the spire instrument which was worked on at Edinburgh this is still pretty exciting!
ok perhaps not as catchy as “in space no one can hear you scream!” but its a pretty apt description of the work of a number of condensed matter physisits who have recent created the worlds first acoustic black hole. Now I know what you are thinking … it was the same thought I had as soon as I heard about this work : acoustic black hole + coldplay = a better world for us all. In my head its like those flying flat prison things from superman … but we let out the brutal superhuman dictator and replace him with the far greater evil of coldplay
Seriously though this is some really cool stuff. As we all know in our current theory of gravity, matter and energy bend space and time around it and in turn light and matter will move along the contours of this curvature. In a black hole the density of the matter/energy doing the warping of space time is so great that light (and everything else) is unable to escape from that region. Now what you might not have known (I certainly didn’t!) is that it turns out that in a certain state of matter, known as a Bose-Einstein condensate, the equations which govern the paths of sound through the matter are the same as those which govern how light travels along the curvature of space. This throws up an pretty intriguing idea: could we create within a Bose-Einstein condensate a region from which no sound can escape? A form of coldplay prison acoustic black hole?
Well it turns out that not only is the answer a resounding “hell yeah!” but some scientists form the Israel Institute of Technology, in Haifa have done just that. They created a region within the Bose-Einstein condensate which had a supersonic flow, that is the material which makes up the condensate is moving faster than sound. Within this region little packets of sound called phonons (an analogous version of photons but for sound instead of light) can never escape this region. Its sort of like running on one of those flat escalators that you get at airports, if its moving faster than you can run you can never get off it. The border between the supersonic region and the rest of the condensate then acts like an event horizon in regular black holes.
One of the things I love about science is how in some rare cases it can make the seemingly impossible happen. Its something that’s encapsulated in Arthur C Clark’s third law:
“Any sufficiently advanced technology is indistinguishable from magic”
Or as I think should the moto of all engineers and product designers:
“Any technology distinguishable from magic is insufficiently advanced.”
Occasionally working in science and actually more often science communication you come across situations where despite knowing exactly how something works it still feels like there is a little bit of real magic in the world. I think this is why a lot of the same people who get in to science also love movies and books about fantasy and the fantastic, regardless of the world or setting they are always looking for things that simple make them think : hell yeah that’s cool!
A while ago we had a visit form Ben Craven, a master of creating magic from science. At a workshop for science communication Ben brought along a bag of his tricks to wow us all. After messing with our sense of colour and got us scrattching our heads with his gravity defying machine (well perhaps intuition defying would be a better description) he allowed us for a brief few minutes to pretend like we where fire wielding superheroes. While I look a little nonchalant about my new super power I think that the expression on Rita’s face conveys how unbelievably cool this felt. Of course the real magic is that it isnt really magic at all. Ben simply bubbled some gas through a soapy water solution to make bubbles full of flammable gas, a little water on our hands to stop them burning and a healthy deposit of the magic bubbles later and you have your very own flaming hand! AWESOME.
Some people will say that knowing the ticks destroys the magic. The same people will usually also tell you that knowing what causes the aurora or why the sunset is the colour it is takes away from their beauty. I know it’s a sentiment that has been expressed before by many people but whenever I get to do things like set my hand on fire it just reminds me of how wrong these people are. The wonder is in the explanation, the magic is in the ability to make something cool happen within the rules of nature not by breaking them … and I always want to know the secret to the magic trick.
Incidentally we are still waiting for our invitation to join the xmen