MS. REBECCA SHEIR
But first, let's go up, way up to the stars, though it's not really the stars we're interested in here, per se, it's the stuff in between them. These teensy weensy grains known as interstellar dust, interstellar dust...
UNIDENTIFIED MALE 1
What does that even mean?
You know, we suffer from the name, just to begin with. You know, you talk about dust and people right away start falling asleep.
But this guy could talk about dust all day long and stay wide awake. His name is Ulysses John Sofia, Professor Ulysses John Sofia.
PROFESSOR ULYSSES JOHN SOFIA
Yeah, Professor Sofia is so...my father.
U.J.'s father, Sabatino, teaches astrophysics at Yale. U.J. teaches at American University.
I'm the chair of the Physics Department.
And he's one of just 200 people in the world studying these tiny grains.
They're sort of the size of particles in cigarette smoke.
U.J. says they clump together in space.
And they're few and far between and most people never know that they exist. And most people don't care about them.
Why should we care about them?
The average person on the street shouldn't. (laugh) So, realistically they do not affect your life in many ways at all.
But before U.J. sells himself completely short, he's a charmingly self-deprecating fellow, you should know these particles aren't just interstellar schmutz. They're the building blocks of all kinds of stuff in the universe from stars to planets, to, well, us.
We have to appreciate dust as the place that we all originated, right? Without dust, we wouldn't be here.
Ashes to ashes, dust to dust.
There you go. I mean, your mother may have said nasty things about dust, but it's good, it's good.
But as to why U.J. has spent 25 years studying this dust between the stars, it has more to do with what a nuisance it is to astrophysicists. See, unlike other sciences where you can sit in the lab, handle specimens, look at slides under a microscope, that sort of thing, in astrophysics...
Everything that we study, stars, galaxies, is extremely far away and the only way that we get information from them is from light.
U.J. gets almost all his data from the Hubble Space Telescope which captures super-detailed images of light from stars. But the interstellar dust distorts that light.
So we aren't getting the proper information about these things that are far away.
For instance, we've all heard about how the universe is expanding, right, like that classic scene from "Annie Hall" where young Alvy and his mother visit Dr. Flicker.
He's been depressed. All of a sudden, he can't do anything. It's something he read.
The universe is expanding.
The universe is expanding?
Well, the universe is everything and if it's expanding, suddenly it will break apart and that will be the end of everything.
Well, not only is the universe expanding, but in the past 20 years, we've discovered it seems to be expanding faster and faster with time. But some people in the science community say that isn't true. It's the distortion from dust that makes it seem like it's speeding up. So they wouldn't quite say Dr. Flicker was right...
It won't be expanding for billions of years yet, Alvy. We've got to try and enjoy ourselves while we're here, ah? ah? ah? (laugh)
But they would say we have to fix this dust distortion problem so we're not flubbing other calculations and extrapolations about the universe. So how do you fix it? U.J. says you start by figuring out what the dust is made of. But here's the rub. Like we said before, it's far away, too far away to study closely.
So what do we do? Because dust isn't giving us enough information itself, is we look at gas that lives with the dust.
See, together the gas and dust form clouds in what's known as the interstellar medium.
So when you look at the interstellar medium, which you have probably never done before...
That isn't to say I haven't wanted to...
I'm sure everybody secretly does. The gas is mostly hydrogen helium.
In fact 99 percent of all the atoms in the universe are hydrogen and helium.
But those are not atoms that contribute to dust so it's only the 1 percent of other stuff that will clump together in these little solid particles.
So let's say you're looking at a Hubble image of a gas and dust cloud. If you're as astrophysically-savvy as U.J. you'll then form an idea of what's in that cloud, like say, oxides.
We've discovered that there have to be oxides in space. There have to be things like rusty iron in space.
And this iron is in the gas and in the dust so think about it. If you know how much iron should be in the interstellar medium as a whole, you can use the Hubble image to get a read on how much iron is in just the gas.
And if it's not as much as we expect, then we can assume that the part that we're not seeing has clumped together into dust.
The next step in combating the whole light distortion problem is figuring out what those oxides are...
...is the ratio between oxygen and iron in these grains so we can figure out the exact type of mineral and then we can figure out exactly what the distortions are and then eventually correct for that.
U.J. isn't sure when they'll get to the bottom of that mystery, but in the meantime, he has several projects in the works. The first is an unofficial public relations campaign of sorts to raise the profile of his beloved research subject.
When I'm trying to get people interested in it, I usually go with calling it cosmic grains first because cosmic grains sounds much more enticing than interstellar dust, I think.
It also kind of sounds like a weird breakfast cereal we'd have in outer space.
It does kind of and I think people have that picture in their mind and so they get sucked into it so it's all about getting that grab and then bringing people in.
U.J.'s other project involves teaming up with the other Professor Sofia, his dad. They're studying something a little bit larger than those cigarette smoke-sized grains between the stars. The two Sofias are attempting to measure the size and energy variation of the sun. If you'd like to pour yourself a big old bowl of cosmic grains or learn more about interstellar dust anyway, visit our website, metroconnection.org
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