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Thursday 30 April 2015

EM drive and Starsailing... the road to a real stardrive?

The hunt is on for the next big thing in space drives: When ion drive came onto the scene they opened up a whole range of destinations such as Ceres and Vesta for exploration, with their low-thrust-high -fficiency combo. But what's the next step along the road to hyperdrive? Well there are a number of ideas that are trying to do away with one of the fundamental things of a rocket: Propellant.

Why? Propellant is heavy - for every gram of it you carry to make you go fast the more you need more to push it. Take propellant out of the equation and space travel can get a whole lot faster....

The wild card: EM drive.

You may well have read or heard something about this recently, and I'll be very surprised if you don't hear more about it - be that good or bad. The 'EM drive' is an idea for an engine that consists of a cone shaped box, inside which microwaves bounce from the pointy end to the flat end.

Yes there's more to it than that: There's a magnetron to produce the microwaves, the 'box' is a high Q resonant cavity (high Q means the box doesn't leak microwaves very much, resonant cavity means it traps microwaves of a particular frequency). But basically: Cone shaped box full of bouncing microwaves. Set one of these up and - apparently - it will produce a very tiny force in one direction.

Above: The prototype EM drive. Even NASA isn't sure it works, or if it works. And they've been testing it for years now. That's even longer than the Rubicks cube took them. Courtesy of emdrive.com
This is very, very, strange, as nothing is apparently entering or leaving the cavity - so it's very hard to see what the device is getting purchase on or thrusting with. A number of explanations have been put forwards to explain the thrust. At first they were the sceptical (and, believe me, there are a lot of people being zealously sceptical about this) type, such as air currents caused by stray heat from the magnetron fooling the force meters.

Then more rigorous tests began to eliminate some of the possibilities - conducting a test in a vacuum chamber to eliminate possible air effects is the most recent (here's a blow by blow account of the most recent developments) - and more exotic explanations are being advanced. Amongst these are the cavity interacting with the sea of quantum vacuum particles theorised to permeate the universe, a highly mathematical explanation involving radiation pressure from the discoverer of the cavity effect, and, yes, space warps. For more information, here's the EM drive website

I'm keeping my scepticism up, but I'm also interested to see what explanation eventually emerges, and it would be much more exciting if it was something exotic! Some parts of the scientific community seem to be so upset by this machine (to be fair it does seem to violate conservation of momentum, which is a very basic law) that it's hard not to feel like they're taking what should be an academic, technical, discussion personally.
It might be worth remembering that, while the have been plenty of false alarms (faster than light neutrinos.... anyone remember that?) down the years, some significant discoveries (solar wind, quasi crystals, relativity) were greeted by massive scepticism too. I suggest we keep our sceptical heads on, by stay cool about it all, and make up our own minds based on the evidence that unfolds - rather than being dragged along with the crowd either way.
Space  sails:
Sails are a good example of a more down to earth engine that doesn't need a supply of on board propellant. However, unlike the EM drive, they do get their momentum from a well understood source -  the wind (even if that wind is a very different one than we have on Earth)....


Above: NASA explains solar wind, and how it effects Earth.

On Earth moving things by attaching sails to them and catching the wind is such a good idea that it's still around today. True, in the last hundred years the reliability of the internal combustion engine has edged out the sail for large ships, but for pleasure the sail still has a multitude of very cool applications...



Above: Sail doesn't have to be slow, or work only on the water -  the Greenbird land yacht reached 126 mph under sail power.Courtesy of Yachtpals.com

So what's the point of a sail in space? Space is a vacuum right?

Right...ish. Space does actually have stuff in it - mainly electrically charged (ionised) gas. It's very thinly spread, but moves at very, very, high speeds. This ionised gas makes up the solar wind - a non stop gale, blowing from the Sun.  It averages 400,000 meters a second, and can reach up to 750,000 meters a second - ten to twenty times faster than our fastest spaceships.
The important phrase is 'electrically charged': Electrically charged things will repel off of other electrically charged things with the same kind of charge, which gives us a nice recipe for a sail that can catch the solar wind: A long wire with the same charge sign as the wind itself will do the job.

So that's what a number of groups are working to build - a small lightweight craft with long trailing wires that unreel to catch the solar wind. One of them, called Aalto-1, would not only be one of the first solar wind sails, but also Finland's first home grown student space satellite!

Above the Aalto-1 satellite project, a mission hoping to be the first operational solar wind sail.

Although I've been following the development of this technology for a while,  I hadn't realised that there has been one,  Estcube,  that already launched -  the satellite succeeded in communicating with Earth but was unable to confirm the wire rolled out successfully. Not bad, considering that this was the first ever Estonian satellite.

 Above: A model of the teensy 'Estcube' satellite.

Still,  there are limits to what speed a solar wind sail could reach: it would take thousands of years to reach another solar system (a big improvement over tens of thousands with or current engines,  but still) so we'll eventually need something a bit faster

Light sails:

Which brings me to the other kind of space sail: Photon sails. Photons are particles of light, and they carry momentum - so when they bounce off something they exert a very, very, small force on it. If you attach a huge, reflective, lightweight, sail to your spaceship you can catch enough of that push to gradually build up speed. The process is slow, but (in principle) over time the only maximum limit is lightspeed, as that's how fast the photon 'wind' is going. In reality you'd need to turbo charge the sail by shining a laser on it to get to a significant fraction of lightspeed, but that's still a lot less energy intensive than getting up to that sort of speeds by rocket.

....

Above: Why it's possible to use light the same way we use wind - the long version, so put the kettlê on. Courtesy of JAXA.

...Of all the emerging propelentless technologies this is by far the best tested - Japan launched a successful prototype called IKAROS not too long agoand the Planetary Society plan to launch a miniature sail powered craft called lightsail-1...


Above: Lightsail 1. Courtesy of the Planetary Society.

...hell, even the bad guy from Star Wars (count Dooku) had one!


Elsewhere in the universe:

New Horizons finds Pluto has ice caps!

The New Horizons space probe has finally gotten close enough to Pluto to see more details than Hubble - it's first find seems to be an ice cap (probably of nitrogen ice). Here's the press conference on the preliminary results:


Elsewhere on the internet:

Mercury probe dies in a blast of light
Russia abandons out of control  spacecraft:
Secret rocket launch by Blue Origin: 
Mathematical analysis hints at unknown physical process happening on the Sun:
Cosmic rays allow electric fields in thunderstorms to be studies.

Monday 27 April 2015

Baby planet Vs black hole, an underdog story of cosmic proportions...



Baby planets Vs Giant black holes

I'll admit I have a real soft spot for the underdog, but I didn't expect it to be touched by a celestial encounter twenty six thousand light years away. That said I didn't expect Madonna to still be going,  terminator like, in the year 2015. So much for my powers of prediction, and this story begins with astronomer's powers of prediction being a bit off as well....

The beast in the night.

Above: A map of the Galactic Centre, courtesy of the Naval Research Laboratory



You may or may not know that in the centre of our galaxy is something that deserves the description 'cosmic monster': A black hole the size of a small solar system. Last year astronomers were wetting themselves with excitement* - a gas cloud, named simply 'G2' was heading for a close pass of the maw. A black hole's gravitational grasp extends far beyond its edge, and the gas cloud (which, on account of it being, y'know, gas, should be pretty flimsy) wasn't expected to pass unscathed. Astronomers are partial to a spot of massive cosmic violence, and in particular they hoped we'd get to see the famous spaghettification effect in action


Above: To explain spaghettification, and the myriad other ways black holes are bad for ones health, I'll hand you over to the always dependable Neil DeGrasse Tyson.

G2 fell towards the gigantic black hole, raced around its edge.... and nothing much happened. The object seemed slightly more spread out, but it was pretty spread to start with. This was both slightly embarrassing and fairly weird for astronomers. After all, it's not as if they can ask a titanic gap in space time for their money back. It seemed as though G2 wasn't what it looked like.

Above: A simulation of what was expected to happen to the G2 'cloud'.

 Now Michela Mapeli and  Emanuele Ripamonti have a possible explanation: Perhaps G2 isn't just a weakly held together cloud of gas. Perhaps its an embryonic planet (link here).

True, planets don't look much like gas clouds, but the planetary embryo of a gas giant is (according to theories) a smeared out blob of gas and dust, denser towards the middle, but without a definite core object until it is mature. There's also the fact that the galactic core is a fat less friendly place than our quite suburb here near the galactic rim: The core is full of massive, super bright, suns that blast out high energy radiation -  radiation which evaporates clouds of gas from almost any surface it strikes.  At the same time the tidal forces from the gigantic central black hole can strip huge blobs of matter off anything not firmly held together, even hundreds of millions of kilometres away. G2 might well be a planetary embryo that has been distorted by these ferocious conditions.

Above: A simulation of planetary embryos forming in a protoplanetary disk. Courtesy of Our Universe Visualised.

A gas giant embryo, in a state halfway between a collapsing gas cloud and a planet, could have all the right properties to explain what has been seen. And if that is the case, it raises some very interesting possibilities - possibilities the paper also touches on: This embryo might be a sign that some of the stars surrounding the black hole aren't formed naturally, but are instead children of the black hole. Giant planets and stars have certain things in common when they form, and something analogous to the process that formed the giant planets in our solar system billions of years ago might be happening in the swirling matter surrounding the black hole, giving birth to stars, planets, brown dwarfs, all living a crowded existence, right on the edge of the greatest destructive force ever discovered.

It's an idea that has a nice yin-yang symmetry to it -  a force of great destruction creating so many things. But All we know for sure right now is that, whatever G2 actually is, it's tougher than anyone expected. Tough enough to tease a super massive black hole and survive, at any rate.

Elsewhere in the universe:

MESSENGER takes the highest resolution image of Mercury ever.

I've been saying for a while now that the MESSENGER probe is doomed -it's out of fuel, the effects of the Sun's gravity will eventually smash it into Mercury's surface, and yet it has just taken this:

Above: Yes, I know this is just a bunch of craters, but it's a bunch of craters taken by a doomed space probe just 8000 meters aboive the surface of Mercury - this is probably the highest resolution image we'll get of the innermost planet in our lifetimes. Courtesy of NASA.
It doesn't look like much, but it was taken by the probe just 8000 meters above the surface, and it's the highest resolution image ever taken. the MESSENGER team are using the very last of the helium gas they've MacGyvere'd as propellant to buy the probe another week before it slams into Mercury....


 
Above: MacGyver, teaching kids that you can build weapons out of household objects since I was a boy. Why'd you think I got into science? Yes, it's the bloke from Stargate SG1. And if those references are too nerdy for you... well, you might actually be someone with a social life.
Elsewhere on the internet:

Hydrothermal vents can produce prebiotic chemicals


Electric solar sail could ship water from the asteroid belt?

First laser cannons, now rail guns for the US navy

* With a few rare exceptions this is not literally true.

Thursday 23 April 2015

S.A.B.R.E and space Geckos


Even though I'm deep into planning a deep space mission to an undiscovered planet........ ok I have lots of work and a mouse nest in my flat,  and that's why I'm really busy.....  but even though I'm a bit pushed there're a few things I can't resist telling you about:

S. A. B. R.E



SABRE stands for Synergetic Air-Breathing Rocket Engine. This is an engine -  well in fact it's more of a design that's on its way to becoming an engine -  that could revolutionise how we fly into space. They are intended to power the Skylon robotic space plane,  which would be the first commercial space launcher that launched like an airplane,  flew into space, did stuff then landed like an airplane.  It could bring the cost of sending things into space waaaay down.  Even better it's British!


Above: A run down on the SABRE engine, courtesy of Reaction Engines

The news on this is that the US airforce research laboratory have looked over the engine's design and decided it's probably going to work (ok there's a bit more to it than that - link here),  which adds to a recent assessment that the Skylon project shows economic promise.  It's all still a long way off but I like to dream about the day I can afford to launch my neighbours DIY tools into space (it sounds like they're about to break through the walls sometimes)...

Elsewhere in the Universe:

Planetary defence:
Did you know there's genuinely such a thing as a planetary defence conference? It's a gathering of scientists and astronomers, who look at threats to our planet from asteroid strikes. The conference has just finished, and here's a link to the site. The whole thing has been recorded, so here's a link to the videos and here's the first one to give you a feel for it where they're going through a rehearsal for if they ever need to confront a real asteroid threat...



There are Geckos in space:
They're part of an experiment into how weightlessness affects biology, but to be honest I just got caught up in this video where their sticky feet give them a huge advantage in microgravity, and let them set up a game between themselves:




Hey, it's Friday, I can't show you all a video about space Geckos playing?

Hubble hits 25:
The granddaddy of space telescopes has been exploring the universe for 25 years - here's a look back (and forwards) on its achievements. This is the full hour and a half version, so put on a cup of tea/coffee and leave the mobile on silent in the next room...


Elsewhere on the internet:

Throttle issue to blame for Falcon 9R crash
...but SpaceX is already at work on the next milestone
Into the void - runaway galaxies
Spectrum of exoplanet seen, tantalising hint of things to come



 

Tuesday 21 April 2015

Massive 'gap' in the universe discovered, and other finds from space...

This week is pretty busy for me (with real world stuff, not just because I've discovered Daredevil on Netflix) but there're already a few bits and pieces of news I'd be daft not to make sure to mention:

Immense void in the Universe discovered:

Above: The supervoid, the buiggest single structure ever found by humanity. Image by Credit: Graphics by Gerg Kránicz. Image credit: ESA Planck Collaboration
Astronomers, led by Dr Dr István Szapudi of the Institute for Astronomy at the University of Hawaii, have discovered that an unexplained cold spot in the cosmic microwave background is actually a vast void -  a gap in the mesh of galaxies making up our universe, 1.3 billion light years across.  Such an immense expanse of empty nothing has strange properties, such as robbing energy from light trying to cross it. If this super void proves to date back to the big bang it might be the signature of some exotic and undiscovered physics at work -  something is definitely up for a void to grow so big.....



Newest images from Ceres:

The latest pictures from the Dawn mission, settling into its orbit of the dwarf planet Ceres, have revealed the mysterious bright spots in greater detail.  One -  the one in this image....

Above: A close up of one bright spot, looking a lot like a crater with a pattern of ejecta around it. Courtesy of NASA

... definitely looks to be the ejecta (probably ice rich) from an impact crater.  But the two brightest -  these two.....
Above: still no d*mn idea what they are. Courtesy of NASA
.... are still a mystery. All the latest images have been compiled into an animation:


One last mission: MESSENGER gets ready to dive bomb Mercury.

The  MESSENGER space probe,  out of hydrazine for its navigational thrusters and using puffs of helium to navigate,  is set to end its days by smashing into Mercury at??? Km an hour. Right now its getting closer and closer to the surface,  taking pictures like these....

Above: The weird terrain of Mercury, warped by unknown processes. I mean, we'll figure them out, and send more spaceships, but right now their weird. Courtesy of NASA.
... and in the end it'll drive into the planets rocks,  vanishing in a blast of unimaginable heat.

YEEEEEE-HAW!!!

Comet jet explodes into life:

The Rosetta mission to comet 67P has had a rough time: the space around the comet is getting increasingly dangerous as the object nears the Sun, filling with dust and gas (as well as larger particles) which obscure the stars and mess with the probes ability to navigate. The probe has backed away to a safer distance. and this week that decision  seems to have been justified as the comet developed a massive, 900 meter wide, new jet of dust and gas in under two minutes:

Above: Yes, this is the comet that looks like rubber bath duck, and the jet is coming from where the ducks bum would be. Insert 'bath bubbles' joke here if you like. Courtesy of ESA
Elsewhere on the internet: 

LEECH sees giant version of our solar system 
Massive black hole merger seen

Sunday 19 April 2015

Searching for a galactic empire?

 
In search of Galactic Empires

When people look for evidence of an alien intelligence at work they're usually looking for something like Earth,  maybe a bit more advanced, maybe a lot more and spread across several worlds or even several star systems. What no one,  as far as I know,  has looked for before is an alien supercivilisation- a civilisation that controls a whole galaxy.

Until now.

Above: Why absorb the power of a whole galaxy? I refer you to Emporor Palpatine in the last moments of this clip for the answer. Courtesy of ... erm.... Disney?




This might sound like the brain child of someone who has been watching too many Star Trek episodes, or who has the Star Wars theme tune playing on a loop in the back of their mind all the time (it's not me, I promise). But it's actually from a team of serious astronomers who've set up a low key scheme called Glimpsing Heat from Alien Technologies (G-HAT). And there is a logic behind this: If you calculate how long it would take to set up a galactic empire... well it's looong in human terms. But compared to the life of most stars, or galaxies, or the universe itself, it's a short span of time (a few million years or so for a really determined race).

True, lots of races might not be interested in that kind of aggressive expansion, lots might be too primitive, might be too energy efficient, or might take steps to conceal themselves from whatever the interstellar equivalent of boogymen are. But if even a handful decided to go the route of 'colonise and dominate' across a whole galaxy we should be able to spot them.
To go into a bit more depth here's a talk (erm, well, a  full hour long lecture) on why that is from the big brains at Oxford University:

 
Above:This is really worth the time to watch - robot butlers lead to destroying the planet Mercury, and then conquering the whole galaxy. With gigantic rail guns. Seriously, Bond villains have nothing on real world physicists. And we could start doing this today.

The reason why we think we should detect any super civilisations is that there's a law of physics that says any energy using machine will give out heat (it's called the 2nd law of thermodynamics). Assuming that we're right about this law, and as far as we can tell we are, a civilisation spanning a whole galaxy should put out a lot of heat. What's more, such a civilisation would probably use the most obvious sources of power to power their empire ; their galaxies stars themselves, so they'd probably be collecting a significant fraction of their galaxies star light with solar panels - and eventually that energy would get re-radiated as heat too. By the way, the term for covering a sun in collectors to absorb all it's power is 'Dyson structure' or 'Dyson sphere' - it's industrilisation gone insanely large scale.


Above: Fraser Cain, editor of Universe Today websoite, gives us a quicker run down on what a Dyson sphere is. 

And, yes, they turn up in Star Trek:

 
Above: The starship Enterprise encounters a Dyson Sphere. Later on they find Scotty trapped in a transporter beam, and a technobabble off between him and Geordi Laforge results in a deadly spacetime rip.
Honest.
The overall effect would be to make the whole galaxy dimmer in the visible light frequencies, and brighter in the infra red, and this is something that the the WISE space telescope might be able to pick up - so GHAT has been combing through its data, looking for any suspect object that might fit the description.

The GHAT team have found a hundred thousand galaxies that definitely aren't heavily modified in this way. That has left just 50 that might - and only might as a theoretical possibility - be evidence of an alien super civilisation using between 50% and 85% of their galactic energy output, and ultimately re-radiating it as heat. These will be followed up by searching for previous studies that can identify them as natural infra red emitters. Several of these objects are newly discovered, and in the team recommend that they be followed up by investigations from both SETI and more conventional astrophysics, because they look interesting even if they're not signs of super space aliens.

Elsewhere in the universe:

Ceres:
Another bit of Ceres related coolness from the image processing gurus at unmannedspaceflight.com:


This back and forth rocking animation of Ceres north pole was put together by the talented Toma B, and helps us to pick out surface details a bit more easily.

Procyon probe has a target (with a Moon) selected: The Procyon probe isn't about space exploration as much as how small a working interplanetary craft can be: It's barely bigger than a big pillow, and is testing an experimental, super lightweight, ion drive and thruster system.

Above: One of the probes experimental, ultra small, thrusters. Courtesy of JAXA
The probes only sensor is a telescope, and when it was launched it didn't even have a destination.... but now it does! It's going to an asteroid called 2000  DP107, which was the first asteroid ever discovered to have it's own moon.
Above: The Procyon micro satellite - one edge is about as long as a larg-ish laptop. If it hadn't gone into space it would have made a very interesting table ornament - it'd be a conversation starter, especially when you mentioned what it cost.... Courtesy of JAXA

Elsewhere on the internet:

Edge of space balloon to explore how cosmic rays damage computers

New dark matter hunter starts this autumn

Dark matter mapped by cosmic shear

New Horizons gets first colour snaps of Pluto 

The Batman Vs Superman trailer is out:


Latest Star Wars trailer is out:




Thursday 16 April 2015

Dawn space probe gets an eyefull of Ceres' north pole

Just a quick note: The Dawn space probe has emerged from the shadow of Ceres, and started sending back images. The first are some beautifull shots of the dwarf planet's north pole:


The mysterious bright spots aren't in view yet, so all us space geeks are going to have to wait a while longer for the next batch of clues to what they are....

Above: Still no idea. Possibly it's graffiti? Courtesy of NASA
Elsewhere on the internet:
Giant galaxies die from the core out
Dark matter shows signs of interacting with itself
Prebiotic molecules found near young sunlike stars

Wednesday 15 April 2015

How to make water on Mars....


The idea that there might be water on Mars has been beguiling and fascinating us for decades. Why? Because, on Earth at least, water means life - and the idea of finding life on another planet fascinates us. It's been known for a while that Mars had plentiful water, even an ocean, billions of years ago.......

Above: NASA explains about the Martian ocean. They do a few cool things like this, have alook around youtube for them!

......and even in later epochs volcanoes would occasionally melt surface ice. But this week some new analysis of the Martian desert (here's the abstract in nature), drawing on both data from the Mars rover Curiosity and the fleet of orbiting space probes, has made it seem that much more likely there is some liquid water still on Mars today (link here).

What has been discovered is a natural antifreeze, called calcium perchlorate, in the soil at Curiosity's location. As well as being an antifreeze calcium perchlorate absorbs moistuire out of the surrounding environment, and when it has absorbed enough a perchlorate particle turns into a droplet of perchlorate saturated water. Here's a video of the process, which is called deliquescence, turning a tiny crystal of regular salt into a droplet under a microscope:

Above: No, that isn't an ice blockmelting, it's a tiny crystal of table salt absorbing enough water to become a droplet of hypersaline water.


On Earth hypersaline (very,very salty) water forms pools that stay liquid even down to -50 degrees celcius. On Mars the ability to stay liquid at low temperatures has a double benefit: It keeps the water from freezing solid, and it keeps the liquid from evaporating away in the very thin atmosphere.

The Copenhagen team haven't found any lakes, but what they have done is use curiosity to measure how much water vapour the soil is absorbing out of the thin martian air - and it seems that enough is being taken up to form these antifreeze laden drops. The soil also contains evidence of these droplets migrating through the soil and into the ground. While this isn't as promising as a direct detection of water would be, it is an interesting find, and increases the chances that areas on Mars nearer the poles, with more vapour in the atmosphere, might be able to form enough water to support hardy microbes.

Above: Don Juan pond in
Antarctica, where the salts in the water keep it liquid even at minus fifty degrees celcius. Put your fingers in and... well that'd be waste of fingers. Courtesy of the British Antarctic Survey. 

Elsewhere in the universe:

Evidence for a Martian ocean, water activity in gullies,  and subsurface lakes:
The European Geophysical Union has given a press conference , outlining three new water related lines of evidence about Mars: The first speaker gives more evidence supporting the idea that Mars had an ocean in ancient times, the second talks about how some martian gullies may have formed by wet debris flows, and the third describes how large floods came bursting from underground resevoirs. The EGU haven't made a copy of this on embeddable yet, so here's the link.

Even more on Marian water: Martian mountain might be 'leaking':
A mountain system on Mars shows signs that rust and salt polluted water might be leaking out from underground reservoirs on a yearly basis.

Above: The redder streaks running down this mountain might be formed by rust polluted water running down the flanks until it evaporates. Or not. If it is, and you're reading this from Mars near that mountain (anything is possible), don't drink the stuff. Courtesy of HiRiSE

SpaceX successfully launches supplies and experiments to the space station, but just misses re-usability goal:
Elon Musks SpaceX company has successfully launched one of their Dragon spacecraft to the international space station, with a cargo of supplies and experiments. The company came close to landing the rockets first stage on its ocean barge/landing pad,  but it toppled over and broke into pieces moments after touchdown.


Above: Ooooh.... that was so close! The rocket actually lands safely on the pad,but just after this finishes it fell over! I'll take the glass half full point of view - this bodes really well for the next try! Courtesy of SpaceX.

Vulcan rockets to launch in 2019, will try a different take on re-usability
The ULA designed Vulcan rockets will parachute their engines back to Earth. Facing ever stiffer competition,  and demand for lower prices, United Launch Alliance is hoping its innovative design wil help it keep its competative edge.

Monday 13 April 2015

Opinion: Apollo 13 to today - how far have we come?




Apollo 13 to today - how far have we come?

This Monday is the 45th anniversary of the Apollo 13 mission. In case you don't know what happened - it was 45 years ago, c`mon, some people seriously won't have - it was a crewed spaceship, on an exploration mission to the Moon.One of the crew called mission control and said "We've had a problem". Now, this was at a time when space travel was solely for the bad assest of the bad assest, so the problem was that... um well check out this re-enactment from the (historically very accurate)movie with Tom Hanks :

Above: Tom Hanks tries to explain to his space ship that now wasn't a great time to do terrible thing it just did. Courtesy of movieclips.com

Hollywood does exaggerate things though, doesn't it? Well, in cased you're wondering just how Hollywood that was, here's a photo taken by the crew of how banged up their ship really was :

Above: The top picture is how Apollo 13 looked as the crew abandoned it (well, the service module part at least). The bottom is how it should have looked. Courtesy of NASA

..and to get it from the horses mouth, here's commander Jim Lovell and his crew, speaking at a press conference not long after they made it home:



How far have we come since then? 
Something I hear a lot amongst space advocates is that, with hindsight, Apollo 13 represents a double failure: Not only was the mission a failure that almost killed the crew, but the Apollo missions themselves are a bitter example of how much mankind can achieve in space....... but doesn't. After all, it's been over forty years since humans went beyond Earth orbit.

Above: The Launch of Apollo 17, the last time that humans went into deep space in person. Courtesy of Dan Beaumont film.
This is a point of view held by some very clever people, who were actually involved in Apollo (although by no means all of them), but I disagree:
In 1969 to 1973 we had the massive, cold-war-inspired, effort of Apollo. Riding a budget that was many times bigger than today's (in real terms), with unwavering political support, NASA accomplished the seemingly impossible: It landed people on the Moon:

Above: If I need to tell you what this is then shame on you. Unless you're like five, in which case: It's the first spaceship to land on the Moon. And well done for getting onto my website. Does Mum know you're using her computer..?

But there was no surface exploration of other planets. None of the smart machines we have flying about our solar system today - there were automated probes to other planets but they were crude, simple, and so rare. Indeed, any and every space launch was a major event. No space stations. No reusable spacecraft. The very idea of a private company looking to access space, or build their own ships would have been laughable. Now, for kicks, check out the timeline of space exploration over on Space.com (Link here)

Above: The Millennium Falcon isn't on that timeline. Yet. I have plans....

Look at how many firsts, both exploration, technological (and even in human spaceflight) come after Apollo ended. The end of the Apollo era budgets may have quashed many of the big dreams, but it forced space exploration into an era of innovation it might otherwise have missed. And, thanks to the missions that have flown since Apollo, we have views like this...

Above: Saturn, seen with the Sun behind it, by the Cassini space probe. Courtesy of NASA

...and this....
 


Above: Sunset on Mars,as seen by the Curiosity rover. Courtesy of NASA.
...and this....


Above: A video taken by the MESSENGER probe as it swoops low over the surface of Mercury. Courtesy of NASA.

...and this....
Above: the plumes of Enceladus, where an mysterious heat source is powering geysers and an underground ocean on a small moon of Saturn. Courtesy of NASA.

...available to the whole world. We know that Mars once was a habitable world, and we're on the way to hunting down the best place to look for any life that was there. We've discovered that worlds like Europa, and Enceladus have oceans to explore, that comets carry the chemical building blocks of life, and that Saturn's moon Titan is a very, very weird place that we can learn a lot from. This year we begin exploring Pluto and the Kuiper belt, and the Dawn mission will map the dwarf planets for us.

And as for manned exploration? It's true, we haven't gone beyond Earths protective magnetic field since Apollo. But today space launches to thew biggest, most sophisticated space station ever built, are routine. Even manned flights are a normal thing.


Above: A tour of the International Space Station, the biggest, most sophisticated space laboratory ever built. Courtesy of NASA/ESA.

We have innovative new approaches to space, like the rise of miniaturised space craft: Cubesats and chipsats are opening space to more and more ordinary people. We have the burgeoning space tourism market. We have many, many missions like Hubble, which stay in earth orbit but look out to the stars -  and have discovered alien solar systems, and imaged planets around other stars. That was feat many scientist though would be impossible for centuries in 1970. And all of the above barely begins on all the missions and discoveries we've made.

Would I love to see ts on Mars, a lunar base, or a manned Jupiter mission? Hell yes. It's a crying shame that space exploration doesn't receive the same high priority treatment that Apollo did, all across the world. But can we really say we've not done anything great since Apollo, that what the crew of Apollo 13 risked their lives for (and other crews died for) has never come to pass?

I suggest this: Go to the timeline of space exploration I linked earlier. Put a few of the missions there into Google, read about the discoveries, and the future plans. I think you'll see: We've come a long way since Apollo 13.

Elsewhere in the Universe:

Conditions for liquid water to form exist at Curiosity rover landing site:
A team from Copenhagen have looked through the data returned by the mars rover Curiosity, and found that the conditions for liquid water to form exist there. A form of perchlorate salt in the soil is able, under the right atmospheric conditions, to suck moisture out of the air until it becomes droplet of salty water. Even a tiny amuont of confirmed liquid water on Mars raises the chances of some form of live clinging on there, and this makes it seem all the more likely.

25th anniversary of the the Pegasus rocket:
The Pegasus is a unique launcher, because it is carried above the lowest, thickest layers of atmosphere by an airplane before launching:


Above: Pegasus launches the IRIS  satellite.
 
Similar systems, involving jet fighters, are being planned by both private companies and by the DARPA  agency. This week is the 25th anniversary of the pegasus system, showing that such a launcher has the commercial staying power needed to succeed.

Elsewhere on the internet:
Titan storms explain giant dunes
Colour map of CERES reveals an active world

Friday 10 April 2015

The MESSENGER nears the end of the journey - but what’s that in the shadows?


The MESSENGER mission to Mercury is winding down. The navigation thrusters are exhausted, and the team have directed their probe to make series of ultra low altitude passes over the surface, so that they can make the most use of the magnetometer and the neutron spectrometer (which measure the magnetic field and the surface composition respectively). They're already getting pretty low over the surface, but now they'll come within a few kilometres of Mercury's rocks and take videos like this:

Above: This video was taken by the MESSENGER  spacecraft as it flew low over Mercury - keep your eyes open, there are some of the surface features mentioned in tHis post wizzing past the camera! Courtesy of NASA
This will be the final phase of the mission - but fascinating things about Mercury are still emerging. They will keep doing so for years I expect - it needs a lot of time to sift through the mountains of data a space probe collects, and find that thar gud stuff. But at the 46th Lunar and Planetary Science Conference this year there were two tantalising mercury findings from MESSENGER, both pointing to alien geological processes at work:

Something hidden in the eternal night:

Above: Permanently shadowed craters at the poles of Mercury. Yes, I know they're all red and yellow, that's just the graphics. Courtesy of NASA
Mercury, like our Moon, has permanent regions of darkness near the poles, and these have a layer of reflective water ice coating their floors. That ice might have come from comet impacts, or might have been caused by the rocks of Mercury chemically interacting with the solar wind. Although it's weird that a world so near the Sun would have lots of ice, it makes sense because Mercury has no atmosphere to level out its temperatures. So, although the surface of Mercury is oven-hot in the sunlight, in the shadowed regions it's incredibly cold - cold enough for the ice to accumulate and be stable.

Above: Colder than that. Colder than that if you had to spend the night at the bottom of those stairs. After your wife caught you spending the kid's college fund on beer and Doritos. Courtesy of NASA.
That's a big deal in itself, but the story takes a twist when we look at craters and valleys that are a bit further from the poles, and just a touch too warm to let ice be stable over the long term. Here MESSENGER doesn't see a layer of reflective water ice. Instead it sees craters filled with a layer of .....something. Something very dark.


Above: Something even darker than the lyrics of black metal band Marduk. And, in case the outfits and the genre weren't a clue, they write... well, not nursery rhymes. At least I hope none of you are playing your kids Marduk as nursery rhymes. Mind you, have you ever read the originals of fairy stories? Courtesy of MusicTimes
Black materials are common in the solar system, but what's strange here is this: Over Mercury’s lifespan the relentless bombardment of meteorite impacts should have blurred and smeared the boundaries of any patch of material on the surface, but the edges of the black layer are almost razor sharp. It could just be one of those odd coincidences that this stuff formed just as MESSENGER arrived, but it seems more likely that the edges are somehow being repaired.

Self repairing black masses, hiding in the bottom of permanently shadowed craters, on a sun drenched planet -  now that's the kind of alien phenomena we go into space to discover.

Other sensors carried by MESSENGER, like the radar sounding experiment, suggest that there’s a layer of water ice beneath the black material, so the leading theory is that the ice in the craters has some kind of organic material mixed in with it. As ice in these these craters isn't stable over the long term the ice gradually evaporates, leaving behind a layer of organic chemicals on the surface. The layer then protects and preserves the remaining ice. If the layer is breached then the newly exposed ice repeats the processes. These organic materials could even contain compounds related to the origin of life, as similar deposits on the moon are thought to.

But right now this is just our best guess - this might be possible if the ice was mainly due to accumulated comets strikes, as they’re rich in both ice and organics. But if the water molecules are formed chemically from solar wind and the rocks it’s harder to see where the organics could be coming from.

Different flavours of hollows:

Above: These weird hollows seem to be caused by something undermining the top layer of rock and soil, and are growing all over the planet (BTW, this is a very exaggerated colour image, to bring out the details). I'm not saying it's Mercurian mole people. That'd be crazy, and besides they might have agents here on Earth who'd undermine my house if I gave them away... Image courtesy of NASA.
These weird looking holes in the Mercury's crust have been  showing up in MESSENGER images since the probe arrived: They’re areas of ground that have been eroded away in a mould-like pattern by some unknown process, all to roughly the same depth, all across the planet. Crater counting shows them to be geologically young, and probably forming still today. But exactly what process has created them… it’s a mystery.
One idea is that there are stores of volatiles below the surface, and that, as these evaporate beneath the blazing Sun, they cause the ground to collapse. But again, we're into 'best scientific guess' land here. To thicken the plot: At LPSC some of the UV spectrometer results from MESSENGER were revealed, showing that some of the hollows have different surface compositions – this might represent inherent differences, or it might be that some of the craters are older and space weathering has changed their surfaces.

Mercury has turned out to be far from a dead chunk of rock  -  the above are just a couple of the mysteries we've found there. Wouldn't it be great if there was a follow up mission being developed? well there is, it's called Bepicolumbo!


Above: A quick rundown on the upcoming Bepicolumbo mission, courtesy of ESA.

Elsewhere in the universe:
Above: A depiction of the Methyl Cyanide molecule. The 'H's are hydrogen atoms, the 'C''s are carbons, and the N is a nitrogen

Molecules implicated in the origins of life have been spotted in a still forming solar system. The Methyl cyanide molecule, and its simpler sibling hydrogen cyanide, are thought to be amongst the ground level molecules for the chemical evolution that leads to life, so their detection suggests that they’re present in a lot of young planetary systems – great news for alien hunters as it raises the possibilities of finding worlds with the chemistry needed for life. This isn’t the first time complex , life related molecules have been found – sugars have been found, amino acids have been shown to form on interstellar dust, and tar like compounds have been found in distant reaches of the universe. But this is the first time molecules so directly life related have been found in a growing solar system – not too dissimilar to the way our own is thought to have been 4.5 billion years ago.

SpaceX is going to make another attempt to land and re-use it's Falcon 9R rocket. their last attempt came close but...well here's the video:

Above: Owch. But, I should point out, SpaceX shared this video themselves - that's how sure they are they know what went wrong and can get it right.

Lastly, this is pure science fiction, but it's awseome. And it's being made into a movie!


Elsewhere on the internet:

Monday 6 April 2015

Mission into the inferno

Happy Easter everyone!

  Above: I have a stomach bug, and I look hanging so I'm not showing my face - but I'll show you how I track sunspots and solar facula* instead.
Mission into the inferno:

For most of our history mankind has been wondering what the big bright thing in the sky actually is.

No. No, it's not a big torch.Why would it be up there? It belongs in someones garage. I'm talking about the Sun you loonies.




Now we have telescopes, spaceships, and supercomputers, and we're finding out that the big bright Sun is a star, and it has all kinds of weird and wonderful features. In fact, the more we observe the Sun in detail the more of a complex and astounding place it becomes. For example: In 2013 the University of Central Lancashire launched a set of experimental optics into space on a sounding rocket about a year ago, to observe the UV Sun with five times the detail ever seen before. What they found (link here) was astounding:

"....small clumps of electrified gas (plasma) at a temperature of about one million degrees Celsius are seen racing along highways shaped by the Sun's magnetic field. These blobs travel at around 80 km per second (the equivalent of 235 times the speed of sound on Earth), fast enough to travel the distance from Glasgow to London in 7 seconds. The highways are 450 km across, roughly the length of Ireland from north to south.... ....Astronomers have long struggled to understand why, with a temperature of two million degrees, the corona is around 400 times hotter than the solar surface. Hi-C images reveal dynamic bright dots which switch on and off at high speed. These 'sparkles' typically last around 25 seconds, are about 680 km across (the size of the UK) and release at least one million million million million Joules of energy in each event or around 10,000 times the annual energy consumption of the population of the UK (based on information from the UK Department of Energy and Climate Change). The sparkles are thus a clear signal that enormous amounts of energy are being added into the corona and may then be released violently to heat the plasma"

Above: A video made from the images collected by the UClan mission. Courtesy of University of Central Lancashire.

Partly because of the complexities and mysteries of the Sun, and partly because most scientists and engineers view the story of Icarus as a challenge rather than a warning, a space mission is under development that will fly a robot space probe into the Sun's atmosphere. Launching in 2018, this will be extreme engineering at its most extreme: Over six years Solar Probe Plus will perform six slingshots of the planet Venus, to change its course and velocity. Then, as it falls past Mercury under the Sun's immense gravity, the probe will reach speeds of over 200 km per second.


Above: A CGI image of the completed probe, leaving Earth orbit. The solar panels are stowed away, behind the heat shield, and frankly the whole thing looks like it's flying backwards to me, but then it's not built for looks it's built to nosedive the Sun and get away with it. Image courtesy of NASA
The Sun will be a wall of light and heat, filling its sky, so the probes heatshield will be one of the most heatproof things ever built: A carbon-carbon carbon foam barrier 4 inches thick and weighing 1,350 lb. Sat in the shield's shadow, the probe will draw power from the torrent of light around it using solar panels - but normal panels would fry in the heat, so these will need to be cooled. But the heat isn't the only problem: High speed particles and dust, driven by the immense magnetic fields, will be just as much of a danger.

What mysteries would make it worth sending a multi-million dollar robot into such a furnace? Here are a few of them:

How does the solar wind begin?
The solar wind is a high speed stream of plasma sent out by the Sun. When it gets choppy we get solar storms, radiation spikes, aurora..... and damaged to satellites, and even to power grids here on Earth. But we understand very little about how the solar gets its speed and power.



Above: The tenous gas of the solar wind can wreak surprising havoc when it gets mad....

How complex is the structure of the magnetic field near the Sun's surface?
Everything about the Sun involves its immense magnetism in some way, and mapping the magnetic fields in detail will help us understand how our star works. Flares, prominences, storms, sunspots - they all grow out of the Sun's twisted and gnarled magnetic field.


Above: NASA gives a quick explanation of how the Sun is about to do something really strange...

What role does 'complex plasma' (ionised gas mixed with electrically charged dust) play in the mechanisms of the suns surface? 
Complex plasmas are known to behave in incredibly rich and complex ways - it can act like a crystal, a fluid, a vortex, or a flow. It can change the way magnetic and electric field propagate and have even been theorised to host patterns that are a deep space analogue to DNA.

For a bit more information - and by that I mean a lot more information - make a cup of tea or coffee and sit down to watch SETI's Stuart Bale give a talk on the mission:



Elsewhere in the Univerese:
For a long time people have wondered about colonising the Moon, but the harsh lunar surface - temperature swings of hundreds of degrees, micrometeorites, the full blast of solar storms, other kinds of radiation like cosmic rays - makes a tough challenge. To get around this it's been proposed that colonists might build their homes in the lava tubes - tunnels through the rock which lava flowed along in the ancient past:



Above: Lava breaking out of a lava tube and onto the surface. Courtesy of 
 
Now a theoretical study from Purdue University suggests that these tunnels might be  up to 5 kilometres across . Easily big enough to hold a city. The key to their immense size would be a combination of low low lunar gravity and the naturally strong arches lava tubes form.

Elsewhere on the internet:

Young star develops visibly over 18 years

White dwarf to blame for supernova

Black holes don't destroy information

Dark matter doesn't even 'see' itself.

* This is not a rude word, it's a brighter spot on the Sun. Shame on you...... and me, since I must've thought that too.

Wednesday 1 April 2015

Can clouds of atoms pin down dark energy?

Dark energy: It's one of cosmology's big mysteries. It also proves that scientists can  do a cool name if they try - it sounds sexy as hell and it's been name checked in all the cool sci-fi movies. But we don't have a clue what it actually is.

Above: In the Marvel movie universe it's embodied by this big glowing dice. Real world cosmologists would find that much more convenient to study I suspect...



While the nature of dark energy isn't a matter of immediate panic it is a source of long term worry, as it's  tearing the universe apart - if it keeps accelerating the expansion of space all the other galaxies will eventually disappear at faster than light speeds*. It's slightly embarrassing to be facing  the end of creation as we know it without a clue as to why, so it's something we'd like to get a handle on. For a slightly less melodramatic explanation here's the big brains at Imperial College (warning, this is a full blown physics lecture, so put a cup of tea/coffee on):


One of the suspects in our man hunt is called  a 'chameleon field'. The chameleon field would be a kind of dark energy that is suppressed by matter (or large concentrations of energy) very well. This would explain some of the stranger aspects of dark energy, like why it seems to be very, very, powerful over very long distances, but can't be measured on Earth. On Earth all the dense matter suppresses it.

Above: Earth. Beautiful and, apparently, inconvenient for dark energy hunters. Courtesy of NASA

But Clare Burrage, Edmund J. Copelanda, and E. A. Hinds at the University of Nottingham have come up with an experiment that, maybe, could measure the dark energy field - if it is the chameleon type. The experiment would consist of a big vacuum chamber containing as much nothing as possible - since the chameleon field is suppressed by matter and energy an empty vessel  is the best chance of bringing it up to detectable levels. A stream of cooled rubidium atoms would be fired through the chamber, while it was weightless. Any unexplained deflection of the atoms could be evidence of the chameleon force. This sort of approach is already used to measure fundamental constants like gravity, so the team has been able to put some upper limits on how big the chameleon field might be. Here's the paper. I'll be interested to see if anything comes of it...

Elsewhere in the universe:

Galaxies in this universe cluster together like... like... well, like galaxies clustering. Things that huge can't really be like much except themselves. But how did galaxy clusters begin? The Herschel and Plank space telescopes have teamed up to look waaaay back in time and find the answer.

Above: The image in the centre is the Plank all sky map, and the little images are the Herschel images of possible galaxy cluster seeds. Courtesy of ESA.

Elsewhere on the internet:

Scuttling_satellites_to_save_space

Suck on this Tatooine

Mapping cosmic rays

An attempt to make robots conscious?

Graphene sandwich produces new form of ice

Radio bursts - alien messages?


*Yes that sounds crazy. Yes it's true: The rules let you do faster than light if space is the thing that's moving rather than you.