When most people think of astronomy they probably think of the planets,
stars and galaxies the way we see them when we look at them in the night sky.
It turns out that visible light only shows part of what's happening in our universe.
Researchers use x-ray, ultraviolet, gamma ray and infrared instruments to peer
through dust and gas, to collect and analyze radiation emitted by objects in
our universe. Join us as we discover how the SOFIA science team at NASA Ames
Research Center is working with the world's largest airborne telescope to
see deeper into our universe than ever before.
To tell us more about infrared astronomy today will be meeting with SOFIA project
scientists Pam Marcum. So Pam, what is infrared astronomy and why is it so
important? Because with longer wavelengths infrared light is redder
than the reddest color that the human eye can detect and so astronomers must
use special detectors in order to take pictures of astronomical objects at
infrared wavelengths. The interesting or useful feature of infrared light is that
infrared light is able to pass readily through materials such as dense clouds
of gas and dust that would block other forms of radiation like visible light.
So what types of things do astronomers like to look at? Things like stars that
are much less masses that our own Sun. Stars that are like the Sun but, have
progressed further along in their evolution they're nearing the end of
their life cycle. Cooled material that has been spewed out by supernova explosions.
Planets, comets, shrouds of dust that surround hot newly formed
stars inside that are actually heating up those little dust grains.
Can you giveus an example of what something that you look like in the infrared?
Well, let me show you some pictures of the Orion constellation,
Specifically, the Horsehead Nebula.
The visible picture shows some really dark areas and those are actually dust
clouds that are obscuring the visible light that's coming from the stars that
lay behind the dust. In the near-infrared, you actually see many, many more stars
and in fact the Horsehead Nebula has practically disappeared and the reason
for that is what you're seeing now is the infrared light going right past all
of the dust so you're actually seeing the stars behind the dust. The mid infrared has
yet a different picture. Same part of the sky but here you're actually seeing the
dust clouds themselves glowing. The dust is warmed at just the right temperature
by those stars to glow at just the right wavelength that the mid infrared
detector is actually able to see the dust.
And here we see all three images side to side and you can really see the
differences, just depending on what wavelength range you look at and these
different ways of looking at the same object really provide a lot of insight
to astronomers when they're studying star formation processes.
Is Infrared astronomy better than studying visible light? Well, infrared astronomy is
complementary to studies at other wavelengths including visible light and
each type of investigation at these different wavelengths comes with their
own advantages as well as unique scientific insights.
Turns out that water, of all things is an infrared astronomers worst enemy.
Humidity in the Earth's atmosphere absorbs infrared light.
Making observations at those wavelengths not possible even from the highest
mountaintop. You know it's kind of ironic to think that an infrared photon may
have been traveling through lots of interstellar dust and gas for thousands
of years only to get stopped dead in its tracks once it enters the Earth's
atmosphere. To tell us more about this SOFIA program we'll be meeting with Sofia
science missioning operations director Eric Young. So, Eric what is SOFIA?
SOFIA is the Stratospheric Observatory for Infrared Astronomy. It's a very highly
modified Boeing 747 that does observations in the infrared and to
really understand what we have with SOFIA you have to think about and
visualize what had to be done to the airplane to make this observatory.
We start off with a Boeing 747 which is one of the largest passenger airplanes
in the world. You have to cut a hole in the side of the airplane about the size
of a garage door, put in a telescope that's ten feet in diameter and then have a
control system that will point this telescope and keep it steady to the angle
of a dime at a distance of a mile. In order to accomplish that we've had a
large team from a lot of different organizations involved.
This included NASA Dryden Flight Research Center,
NASA Ames Research Center,
and the German Aerospace Center.
What makes SOFIA different from other observatories doing infrared astronomy?
Well, the most obvious thing of course, is that it's in an airplane and
it's the biggest flying observatory in the world. It is an airplane that flies
well above most of the water vapor in the Earth's atmosphere and water vapor
as Pam mentioned is the real problem with doing the infrared observations
because it blocks lots of the spectrum.
With SOFIA there's a huge chunk called
the mid and far infrared which is only visible if you get above the Earth's
atmosphere and that makes it unique.
Another unique capability of SOFIA is
the ability to fly to where the observations have to be made.
Can you give us an example of the kind of science SOFIA is doing?
Well SOFIA does all kinds of science. for astronomy.
The observations on SOFIA are open to
astronomers all over the world.
The very best proposals that are judged
by other astronomers that to be on SOFIA
are the ones that get observed.
So, that means if SOFIA does observations,
from looking at things within our own solar system
to nearby stars, stars that are being formed,
all the way out to distant galaxies.
It's only limited by the innovation and really great imagination
of all the astronomers in the world.
To tell us more about the work of the SOFIA
science team we're meeting with NASA Ames Center
Director and astronomer Pete Worden.
So Pete, as an astronomer what do you find
most exciting about SOFIA?
SOFIA is state-of-the-art instrument.
For the first time we're going to be able to get
high-resolution information in the infrared
part of the spectrum region.
This will revolutionize our understanding of, of how
stars form, how planets form and how the very stuff of life forms.
So, who gets to fly on the plane?
The really cool thing about SOFIA
is that not only researchers
get to fly on it,
students get to fly on it.
Not only graduate students and
undergraduates working on this but,
teachers get to fly on it.
The nice thing about an airplane,
which is different from a spacecraft
is that everybody gets to fly on it
and gets to work with the instruments
so it gives people not only
a chance to interact with the science
they're doing in a much more direct way.
But, it also gives people a chance
to feel the excitement of discovery.
SOFIA is connecting a vast amount of science.
What do you see as its ultimate goal?
I think the biggest goal is to
really begin to understand the early
phases of star formation,
planetary formation and the formation of molecules
out of which life emerges.
You know, there the whole field of astrobiology,
That how life began, where else isit in the universe
and what its future is, is tied up in the
kind of discoveries that SOFIA will make.
So it is a major step forward in
understanding who we are
and where we came from.
Thanks for joining us and meet us
again on our next Destination Innovation.
For more information on NASA's SOFIA program
Please visit nasa.gov/sofia