I think it’s fair to say that, given your ‘druthers, you’d want an instrument that could map exoplanets in the kind of detail you get with Google Earth, with enough resolution to actually see the Great Wall of the Klingons, in case they’ve built one.
Could we construct such a telescope … ever?
An interesting discussion and worth a read, but in actual fact we sort-of already have telescopes that are bigger than this. Like, almost twice the diameter.
Y’see, it used to be that to get your telescope to work you needed one big reflector. Bigger the reflector, better the resolution (in the strict physics sense of the word resolution, meaning the ability to distinguish objects as separate from each other).
The biggest single reflector is, as you probably know, the Arecibo radio telescope. And that’s kind of unwieldy and pretty impractical, not least because you can’t point it at anything other than whatever is directly overhead.
Around the 1970s though, computing power got good enough that a new type of telescope became possible, and led to the construction of arrays of smaller dishes, probably the most famous example of which is the imaginatively-named Very Large Array in New Mexico. With a bit of clever programming, the images from all those individual dishes can be stitched together to in effect make the whole thing behave like one really big dish, only with the benefits of being directional and much cheaper to build and maintain.
As computing power has increased, more and more of these array telescopes have been built. MERLIN, one of my favourites because it’s British, takes the input from seven older dishes spread across a couple of hundred miles of the Midlands, puts it all together, and gives you an effective telescope diameter that would be impossible to construct as a single dish (well, unless you had a budget of trillions of pounds and felt like dooming Birmingham and the rest of central England to permanent darkness).
But even with this technology, we’re limited by the size of the Earth, with a diameter of about 8,000 miles, right? And that’s pretty far short of 100 million miles.
Well, not exactly. Because Earth is moving. In six months time you will be 186 million miles away from where you are right now, round the other side of the Sun.
That’s a pretty long exposure photograph, I know, but to get the maximum resolution of deep-space objects, this is exactly what astronomers do. We use the motion of our own planet in orbit to get an effective telescope diameter the same size as the diameter of our orbit. Which is pretty mindblowing to me.
Now, this is currently only really used for radio frequencies, but I would expect it’s not impossible to use a similar system for visible frequencies. Not that it would be much use for identifying features on a planet, as that planet will likely also be spinning on an axis and certainly it will be orbiting a star, and because its orbit would need to be in a fairly narrow range of distances away from that star for it to be habitable, its orbit would be of roughly the same order as our own (a few months to a few years), so over a 6 month exposure that planet will be a blur, but still, we could at least see that it’s there. From the way its atmosphere reflects and transmits light we could detect possible signs of industry. We could make informed guesses about oceans and landmasses. We could even potentially detect signs of life.
And all of that makes me pretty damn excited.
**Best of 2013: Moore’s Law and the Origin of Life**
From the MIT Technology Review.
*As life has evolved, its complexity has increased exponentially, just like Moore’s law. In April, geneticists announced they had extrapolated this trend backwards and found that by this measure, life is older than the Earth itself.*
maybe aliens don’t talk to us because we’re creepy. i mean we send them weird mix tapes and we keep trying to find out where they live
Astronaut readjusts to life back on Earth
> Don’t give him a baby for a while.
HE GRABS THE CUP BUT THEN HE DROPS THE PEN 0.0003 SECONDS LATER
AND HE LOOKS UP AT THE CEILING INSTEAD OF AT THE GROUND WHEN HE CAN’T FIND THEM
From Life, 22 August 1969: photographs of the three Apollo 11 astronauts returning to their wives.
Michael Collins. Who, in case you haven’t read me talking about him before, went damn near all the way to The Moon, and stopped just short because he was piloting the orbiter that collected Armstrong and Aldrin. That’s sacrifice right there. Huge respect for the guy. But now I have even greater respect.
Because SPACE MOUSTACHE.
RIP Neil Armstrong
I’ve seen the Apollo rockets and there is no way in hell I would sit in the command module of one of them.
They are often described as the single most complex machines ever built. Certainly, if a bit of plumbing went wrong, that could be game over, and these things were mostly plumbing. Plumbing that had to withstand crazily extreme conditions of both heat and cold and pressure and everything.
Would you trust a plumber with your life?
Behind all that though, we still rely on the principle that these rockets use, the principle that has been around as long as fireworks - burn some stuff, and as the exhaust gases rush away use them to propel an object.
Twentieth century plumbing, wrapped around sixteenth century principles. Basically untested. And when you look at this thing, it’s not a sleek futuristic triumph of elegance. No, the Apollo rockets have rivets and quite clear large nuts holding their bolts together.
Like I say, I would not want to be on top of that thing.
If they had utterly failed, Neil Armstrong, Buzz Aldrin and Michael Collins would still be heroes of mine, but they were the pinnacle of an American can-do boldness that achieved a thing that, to be perfectly frank, was something we never should have done so early. As a species, men on the Moon at the end of the 1960s was as ridiculously ahead of our time as a steam-powered ramjet would have been a century before.
And yet, this stupidly impossible task, we did it. Humanity landed on the Moon over a century before we really had the technology to do it. We still don’t really have the technology to do it.
The reason Neil Armstrong’s Giant Leap was Great wasn’t simply that he got further from Earth (and the Moon is a lot lot further away than the ISS or than Yuri Gagarin went) than any man before him, wasn’t solely Western territorialism or propaganda, but that given the technology of the time it was fucking impossible and utterly fucking suicidal to even fucking try, and our species managed it anyway.
Imagine cavemen going from hunter-gatherers to having biplanes in a single generation. That’s really what we’re talking about.
I am deeply sad Armstrong has died, but primarily because no one seems to be following him up there. Rest in peace Neil, and I hope we trace your footsteps really soon.
There were times on board when it felt very much like being on a spaceship. The constant, inescapable low-frequency hum of engines far below powering us forwards. Nights at sea, no lights anywhere except for the stars, hanging there in the black. The faint creaks as the entire structure flexed gently around you. And the gravity. The gravity which was, averaged over several seconds, 1g straight down, but as you walked around, “down” would swing slightly left and right, forwards and back, and at any instant could be a little over or under that 1g mark as the floor rose to meet you or fell away from you.
It took two days on dry land for me to finally lose that constant sensation of motion, lying in a perfectly stationary bed as some complicated part of my brain failed to get the message that I was home and desperately tried to compensate for movement that was no longer happening.
Space shuttle Enterprise, mounted atop a NASA 747 Shuttle Carrier Aircraft (SCA), is seen off in the distance behind the Statue of Liberty, Friday, April 27, 2012, in New York. Enterprise was the first shuttle orbiter built for NASA performing test flights in the atmosphere and was incapable of spaceflight. Originally housed at the Smithsonian’s Steven F. Udvar-Hazy Center, Enterprise will be demated from the SCA and placed on a barge that will eventually be moved by tugboat up the Hudson River to the Intrepid Sea, Air & Space Museum in June. Photo Credit: (NASA/Bill Ingalls)
+1000XP for getting this many incredible things in a single shot.
It’s OK, I’ve designed the memorial to me & my future spacefaring adventures I’m expecting you to build. (Taken with instagram)
I think I perfectly captured myself here, except that can of beer may be disappointingly large. Other than that, a perfect representation of reality. I am expecting this to be constructed to stand astride the entrance to Yorkshire Spaceport.
Don’t worry, I’ll construct Yorkshire Spaceport first. It’ll just be up to you to make the statue.
50m high and made of aluminium is fine by me.