Imagine being offered an eyepiece which is linked up to an orbiting satellite telescope, ‘here take a look’ an excited astronomer blurts. You kneel down and squint a little as the rubber seal blocks out the background light of the room, an image crystalises; a tiny dark blue orb floating beside a relatively huge, burning red star. ‘There it is, that’s the planet… the one with life.’
We are fortunately drawing ever closer to that climatic moment of finding neighbors in the universe (or if not, the stunning conclusion that we are a mere aberration of nature). NASA’s Kepler mission launched in 2009 and has found 3500 exoplanets in our tiny patch of the Milky Way, many of them just like Earth. Relatively small, rocky, with continents, oceans, and a placid slow burning star which they orbit at just the right distance.
The sheer number of these exoplanets in our galaxy, many just like our own, all with vast stretches of land blanketed in cloud and weather, wracked by storms, meteorites, and perhaps evolution. If the Kepler mission is anything to go by our universe is crammed. In the Milky Way alone there are 11 billion exoplanets in the habitable zone of their star (calculated via extrapolation). In the universe, there are around 2,000,000,000,000,000,000,000 planets which have the correct conditions for life.
Sara Seager, senior exoplanet researcher at MIT believes that within 20-30 years we’ll have the techniques and tools to look at a planet, do some back of the envelope calculations, and figure out to a degree of accuracy if it has life onboard. She’s calling this decade the modern Copernican Revolution, in that our view of our place in the universe is shifting at least as much as it did when we realised the sun is the center of the solar system.
It’s quite clear that culture has some catching up to do in this respect, NASA’s findings about planets are hardly common knowledge despite their immense potential to alter our perspective of the cosmic neighburhood. Earth is still felt as enormously special and unique by most people (at least in my experience) while wonderful as it is, there are more than likely thousands of cousins in this arm of the galaxy alone.
The new kids on the block:
- Kepler – 7b orbits a huge star about 1400 light years from earth, it’s a gigantic planet almost twice the volume of Jupiter – yet it’s density is the same as polystyrene, 0.166g/cm3.
- Kepler – 16b (8 times earth’s diameter) Orbits round a binary star system, one star about 0.2M and one 0.69M. Like Tatooine from star wars.
- Wasp 12-b Orbits a star with 1.4 times the mass of our sun, but orbits so close to it it does one full orbit in a day. That star’s huge gravity has distorted the planet into a dramatic egg shape due to it’s tiny orbit.
- KOI – 55, two planets orbiting the blue core of a star that went red giant a long time ago. The two planets were deep fried in the blast, but somehow survived and continue their orbits today, they’re each a little smaller then earth. If there are civilisations there it begs the question if they managed to survive, or escape.
- A few days prior to writing NASA found Ross- 128b, an exoplanet about twice earth’s mass that sits comfortably in the habitable zone of it’s cool red dwarf star, with a year of 10 days. It is also tidally locked to it’s star, meaning one side is forever facing it’s sun while the other is in darkness. If life were to evolve on such a planet it’d probably appear quite peculiar to us, as almost every lifeform on earth is governed by a night-day cycle.
It’s an imaginarium Asimov would struggle to dream up. I highly recommend checking the official NASA page out for more. Or better still, get your mitts on ‘NASA eyes’. A program which allows you to explore our patch of the milky way as you wish, you can visit all the solar systems NASA have discovered and see the planets within, artists impressions, masses, radial velocities and distances, star sizes, it’s all in there rendered in high res graphics. Pop on the Blade Runner/Mass Effect theme in the background if you’re feeling indulgent…Yes that’s my average friday night, leave off m8.
With another 1,999,999,999,999,999,996,500 planets to get through there’s probably about everything you can dream up. which more than likely means giant pugs that occupy their planet’s apex predator niche, or perhaps smart ducks.
The difficulty is in translating an observation of a tiny, distant object into an understanding of it’s inhabitants. a case of how we locate this life, so we can investigate, or even trade & communicate with it, or better still, start fracking amongst the local flora and fauna.
The New Launches
What NASA has done over the past few years is great, but it’s croutons compared to the next move. Check out the James Weber Telescope. It has been twenty years in the making, almost nine billion dollars worth. It will be the most powerful space telescope ever, with a collection mirror 7x the area of Hubble’s.
The JW will be able to see the baby galaxies formed right at the start of the universe, looking deeper than before. But it has another mission – exoplanets. What a telescope designed to see tens of billions of light years will see when it’s turned on planets a mere 10 light years away is anyone’s guess. The idea is to use JW’s infared detection to isolate the elements in the atmospheres of these exoplanets. Seager has a developed a method for detecting life on exoplanets by looking at the molecules in their atmospheres. Life of course emits gases (ahem…) but Seager has found they are characteristic, that is planets without life simply won’t produce them.
The method involves waiting for an exoplanet to glide in front of it’s star, and to look at the light which travels through the planet atmosphere as opposed to the raw light from the planet’s sun. By taking away the spectra you can look for the alien gases, or anything else of interest for that matter.
JW will be up early 2019. Nobody knows what JW will see, but if the last big space satellite launch is anything to go by it’ll probs be awesome.
Preceding JW by six months is TESS, another space based telescope designed purely for locating exoplanets. It has four lenses, and will pick out marks for JW to look at more closely. TESS is also the likes of which we’ve never had up in the sky before, and will likely deepen our understanding of the menageries of galactic earth like planets even further.
No missed calls
So we have thousands of neighbors within shouting distance, but no calls…It’s all well and good getting excited about extrapolations and big numbers, but scientists have been listening for decades, and nothing but the signals of stars, black holes, pulsars and the occasional supernova blast have reached us. The cosmos looks like an empty expanse of natural phenomena going through the motions in a seemingly pointless Newtonian clockwork dance, leaving us all wondering, where is the life.
One would expect civilisations, at least ones at our early stage to blast EM signals out into the sky and slingshot probes all over the place. But we’ve encountered neither. What advanced ones will do to communicate is anyone’s guess.
There are three major arguments as to why the universe seems so silent
1. We’ve been listening for about 50 years, that means we can only ‘hear’ in a radius of fifty light years, it’s tiny. The chance of a signal being aimed at us in this miniscule slice of time is close to nil, even if you consider the whole galaxy. The other is that we haven’t been listening well enough. Perhaps our detection kit isn’t up to scratch for listening to a distant signal, or for decoding it from the flux of natural signals
2. Or perhaps civilisations have an expiry date. For instance if we fix a civilisations broadcasting/receiving age at 10,000 years, so about 9500 years older than us, the chance of overlap in our 13 billion year old galaxy is less than 1%… If life has a cycle just like a star, a series of predictable steps whereby it slowly makes its planet unlivable, while failing to crack close to lightspeed travel, well the end is inevitable. There are physical constraints on our survival, and these may be unshakable.
This idea very closely fits observations, and makes a good deal of sense. It also fits in with the rest of the cosmos. Everything appears to exist in cycles, stars, planets which inevitably vaporise when their star goes red giant, elements due to radioative decay, every subatomic particle has a lifetime – even the fundamental ones.
I find it quite freeing in a way, to think of humanity like a brief explosion on the cosmic landscape. It unttethers one from the eternal ‘builder’ mentality whereby we improve for an eternity…Improvement loses it’s objective value, and thus only those activities which are intrinsically rewarding make sense. Power and prestige also lose much of their allure if our species is unavoidably transient.
3. The final explanation is that advanced species have no interest in making contact at this stage. Just as Principia Mathematica would be lost on a chimp, their advancements may be completely beyond our comprehension, science, or even perception. Further they may have reached the maturity to realise that interfering with nature is best left to the less smart civilisations, and merely pinned up a post-it note to look back at Sol’s system in 1000 years for a checkup to see who we’ve elected as the leader of the free world at that point….