You’ve seen this before, right? It’s one of the most famous photos ever taken by the Hubble Space Telescope: three spectacular pillars of dust hanging in space, 6,500 light-years away.
The Pillars of Creation, 1995 Hubble Photo
Now we’ve got a new version. Same clouds. Same stars. Same framing. Shot almost 20 years later by NASA and released this year. Which got me wondering: Has anything changed?
The newer version has a bluer tint (an editor’s choice), but everything else, including those little wisps of dust on the tops of the pillars? They’re the same. The streaks? Gaps? Edges? Shapes? Shadows? Same, same, same, same, and same.
What was I thinking? It’s been only 19 puny Earth years between photo one and photo two. We are talking about enormous structures. It would take five years for a beam of light to cross from the top to the bottom of that horselike cloud on the left. At such scales, 19 Earth years isn’t even a blink. These clouds are so big, the time so short, obviously, there will be nothing new to see.
And yet …
Buried near the end of its press release, NASA mentions one significant change. It’s so subtle, you’d never notice without help. So I wrote Paul Scowen, one of the astrophysicists in charge, and he said, “OK, here it is.”
You see that box in the picture on the left?
The picture on the right is a close up of the box. In it you will see a line of light moving from the bottom to the middle. Twenty years ago, the light reached the point marked by the first arrow, labeled “1995.”
In the newest picture, the light has traveled farther up (like “a stream of water from a garden hose,” says NASA) to the second point, marked “2014.”
60,000,000,000 Miles Later
In the photo, it’s a piddling change, a fraction of a fraction of an inch. And yet, when NASA’s scientists did their calculations, it turned out that that little line of white has been racing along at a furious pace, roughly 450,000 miles per hour. So during the time between photographs, it has “stretched farther into space, across an additional 60 billion miles.”
Whoah! In just 19 years! So what could that be?
(The other pair of arrows at the top of the picture indicate a mystery. Are they connected to the line below? I asked, but no one really knows.)
NASA’s best guess is that the lower line is an enormous, fast-rushing stream of plasma, thrown out by a baby solar system trying to get born.
When a star is trying to pull itself together, as it grows hotter, it often emits an exhaust fume. “You see this kind of thing all the time,” says astrophysicist Ray Villard. He sent me a few pictures, just to give me a taste. Here’s a different baby wannabe star:
And here’s another
Those streaks across the sky, Cal Tech astronomer Mike Brown told me, are “stuff escaping.”
But why? If I’m trying to get hotter and hotter, why would I let matter go? I don’t want to get cooler. I want to combust! I want to become a furnace.
Mike Brown explains that, “A battle is always being fought between gravity, pulling things together, and temperature, which is literally the speed of atoms and molecules moving around.” As a star gathers more and more dust, at its center more and more atoms collide, banging into each other faster and faster and faster, and as they speed up (get hotter), some of them, a random few, reach very high speeds and end up going so fast that they’re like rocket ships—they reach escape velocity and just careen out into space.
Gravity can’t hold them.
I get that. But how come they don’t careen out in all directions, like this?
Baby stars are surrounded by magnetic fields. And when atoms try to escape, they’re grabbed by magnetic bands that look like this:
So up they go, until they’re captured by those U-shaped lines that curve back and return to the star. These atoms are trapped. They shoot up, get lassoed, get forced back. They can’t leave. Except that, if you look closely, at the bottom and the top of the baby star there are field lines that don’t curve back.
You see them there? At either pole? Like little highways into deep space? They either don’t bend or they bend so slightly that, Mike Brown says, “they turn out to never actually connect back … They get tangled up in the galactic magnetic field and are what are called ‘open field lines.’” Open field lines become giant exhaust pipes.
Eventually those careening atoms banging about inside the baby star will find these express exit lanes and whooooosh! They get shot out at crazy speeds billions of miles across the universe.
That’s a healthy thing. It means this infant star is full of spit and muscle. It’s growing. It’s spitting. It’s doing what it’s supposed to do.
So the extra white line in the newest Hubble photo is evidence of a nativity story. A baby star is being born. Unless the baby won’t make it because the nursery is being blown to smithereens.
Will the Baby Be Born?
When astrophysicist Paul Scowen of Arizona State University looked at the first Hubble picture 19 years ago, he remembered being “impressed by how transitory these structures are.” These giant clouds, mighty as they seem, “are actively being ablated away before our very eyes. The ghostly bluish haze around the dense edges of the pillars is material getting heated up and evaporating away into space.”
If you look at the tippy top of the column on the left, you can see wisps of gas flying off, dissolving away. Scowen thinks these three columns were once a single enormous clump but that solar winds have ripped away those in-between spaces, creating enormous cavities.
What About the Baby?
Scowen guesses our little proto-solar system has been spinning itself into being for about 600,000 years. It feeds on the cosmic dust around it. That’s its food, its sustenance. Scowen figures it needs another 300,000 years to become a true star. And the question is, will the dust cloud stay intact long enough to nourish the baby?
“We have caught these pillars at a very unique and short-lived moment in their evolution,” he says. On the one hand, we’ve got this little star furiously trying to gather stuff in, while all around it solar winds from nearby stars and UV radiation are trying to strip and sweep that stuff away.
All we can say is, for the moment, the baby is strong. So far, the newest Hubble photo tells us this is still a Genesis story.
Until it isn’t. But we will root for that soft white line to keep growing.
For the next 300,000 years, I’m keeping my fingers crossed.
Big thanks to astronomer Mike Brown at CalTech, who had to hold my hand through the physics of birthing a star. He kept sending me “this is not quite right” letters as I moved from draft to draft, but if there are any errors, they aren’t his, they’re all mine. And to freelance science reporter (and friend) Angus Chen who taught me some elementary magnetism lessons. Also to Ray Villard at the Space Telescope Science Institute in Maryland and to Arizona State University’s Paul Scowen; without Paul’s arrow pictures, I’d have had no story.
As published on http://phenomena.nationalgeographic.com/2015/06/03/a-baby-hangs-between-life-and-death-in-space/?sf9732072=1