Look Up - Jan 15 2022

 

Look Up

Jan 15 2022

Peering as far as you can

out into space

is like taking the time machine

you never thought possible;

light

from the big bang

that just arrived on earth,

transporting you back

to almost the beginning.

Photons that have travelled

at the speed of light

from matter that no longer exists,

from where it was then

to us, here and now;

as the universe expanded

and the sun condensed out of gas,

as earth cooled

and continents collided

and a man looked up at the sky

and pronounced it good.

Ancient light

preserved for billions years,

like a fossilized animal

found at the bottom of a salt-water sea

that also no longer exists.

So as you progress deeper into space,

capturing ancient light

from objects that are no longer there,

you can observe the cosmos

getting younger and younger;

like snapshots

of what once was but is no more

successively back through the years,

transporting yourself

through time.

Who could ever have imagined

a machine that travels through time?

But squinting through the lens

of a giant telescope

is exactly that,

its small aperture

a keyhole back

to when space and time began.

Or look up at the sky

with your naked eye

on a cold clear night,

when the air is still

and stars laser sharp.

And as your sight adjusts

distant stars will appear

from out of the ether

from fainter and further away.

Drink in

the majesty of heaven

and feel how small you are,

how brief a flicker

before you're gone.

Or walk through a forest

and bathe in the trees

that tower high above;

look up

at the massive evergreens, impassively looming

indifferent to your presence.

They, too, are old,

and contain in their substance

the world as it was

centuries before.

But there is no machine

that can see ahead.

To when the universe

is cold and dark and changeless,

when time ends

and space is flat.

All you can do is imagine.

And as for now,

you already know

how to stop time

whenever you want.

Just look up, and be in the moment.

Because nothing is as urgent as you thought,

and if light can travel

for billions of years

an hour of your time hardly matters.

And if nothing can travel faster

why always such a rush?

The Webb telescope was recently launched. It will collect energy from deep into space, which also means from far back in time.

If you ever look up at the sky on a dark clear night, you can also feel yourself time travel: the way both fainter and more distant stars successively appear as your eyes adjust. It feels as if the universe is opening up before you, and if your eyes were sensitive enough you could peer out to its very edge, and all the way back in time. (Unfortunately, our eyes aren't. And visible light won't get you there anyway. See below if you're curious as to why.*)

Old growth trees are also time travellers. They were standing in the same place when Columbus landed in the new world; perhaps even when the Vikings first set foot in Newfoundland. The molecules in their wood may be from air that Napoleon breathed out.

But where this poem began was not in the telescope as time machine, but in the idea of “nature deficit disorder”: how modernity and urbanization have alienated us from nature, and how we are rejuvenated and re-energized by being out in it. The Japanese concept of “shinrin-yoku” – forest bathing – comes to mind. Which is why the poem ends and begins with stopping and looking up. Taking time more than going back in time. I could just as well have said “stop and smell the roses”, or “be in the moment”; which, actually, I did! I think a big part of this therapeutic effect nature has is to do with humility: the feeling of awe and timelessness it engenders, and the concomitant sense of our own smallness and transience.

Ironically, astronomers – who spend their time exploring the cosmos – are also alienated from nature: they're looking at screens more than space. Because most often, they're not looking up at the sky, or through the lens of an optical telescope, or even seeing pictures: they're looking at computers that contain electronic data transmitted from satellites, radio-telescopes, or arrays of collectors. And even if those data are converted into images, they are still at a remove from the real thing. Screens, just like the rest of us. Everything intermediated.

I was a bit repetitive in trying to explain how looking deeper into space means looking back in time. Probably because I find this a somewhat counter-intuitive and slippery concept, and need to repeatedly explain it to myself! Which I'll do again, here.

The light is ancient, even though we're seeing it now. It brings an image of something that is no longer there. Rather, it was what was there billions of years ago, when the light began its journey. When we look up at that starry sky, we're seeing a ghost of what was; and the further out we see, the longer that light has travelled (light is fast, but not instantaneous!) and so the older a ghost it is. We never see the night sky as it “is”. Only as it appears to us. There is no seeing in “real” time. Only ghostly images successively superimposed, going further out and further back. Which is like time travel. After all, you'd imagine from everyday life that the past is past: at best, it exists in memory, or can be glimpsed in a snapshot. Yet as we look through space, it's all still there: a complete image of the past somehow preserved in this ancient light, still there years later. It seems incredible that we are actually able to see what it was like 13 billion years ago, just a few hundred thousand years after the big bang.

*The Webb is designed to pick up infra-red light, which is what happens as light travels through space: as it loses energy, its wavelength widens and turns into heat, moving from the visible spectrum down to infra-red. The most ancient light is infra-red. You need to see in this wavelength (our eyes can't) if you want to see back far enough in time. So in order to be sensitive to the weakest infra-red without any interference, the satellite must be kept as cool as possible. To do this, it orbits at a distance and speed that not only keeps it far from earth, but also on the far side, so the earth always remains between it and the sun, blocking its heat. (This is accomplished by having the satellite circle the earth in the same period as the earth circles the sun).