SOFIA Seeks Secrets of Planetary Birth

November 19, 2009 by Dauna Coulter
NASA's SOFIA infrared observatory 747SP overflies its home, the Dryden Aircraft Operations Facility in Palmdale, Calif. Credit: NASA/Jim Ross.

You don't always have to have a rocket to do rocket science. Sometimes a mere airplane will do - that is, a mere Boeing 747 toting a 17-ton, 9-foot wide telescope named SOFIA.

Short for Stratospheric Observatory for Infrared Astronomy, SOFIA will observe the universe while gliding through the stratosphere at 45,000 feet. When it begins operations next year, it will be the world's biggest, most advanced airborne observatory.

"SOFIA is set to achieve some spectacular science," says project scientist Pamela Marcum. "For instance, this telescope will help us figure out how planets form and how our own came to be."

And as a mobile observatory, it can fly anywhere, anytime. SOFIA can move into position to capture especially interesting astronomical events such as stellar occultations (when celestial objects cross in front of background stars), while ground-based telescopes fastened to the "wrong" geographic locations on Earth's surface miss the show. SOFIA will fly above the veil of water vapor that surrounds Earth to take a wide-eyed look at the cosmos.

Although our galaxy teems with planetary systems, astronomers don't know exactly how they form. That's because ordinary telescopes can't see through the giant, dense clouds of gas and dust that spawn planets. Using infrared wavelengths, SOFIA can pierce the haze and watch the birthing process - showing scientists how molecules come together to construct worlds.

"SOFIA will be able to locate the 'planetary snowline,' where water vapor turns to ice in the disk of dust and gas around young stars," says Marcum. "That's important because we think that's where gas giants are born. The most massive planetary cores are fashioned [around the snowline] because conditions are best for rock and ice to build up." (Sticky ice particles help form planets just as they help you make a snowball to hurl at an unsuspecting friend.)

"Once a large enough core forms, its gravity becomes strong enough to hold on to gas so more hydrogen and helium molecules can 'stick.' Then these large cores can grow into gas giants like Jupiter and Saturn. Otherwise, they remain as smaller rock-ice planets."

"SOFIA will also be able to pinpoint where basic building blocks like oxygen, methane, and carbon dioxide2 are located within the protoplanetary disk."

Knowing where various substances are located in the disk will cast light on how they come together, from the "ground" up, to form planets.

One of the telescope's key strengths is its ability to complement other infrared observatories. With a 20-year lifetime, it can do follow up studies on objects shorter-lived infrared scopes don't have time to hone in on. If, for example, an orbiting observatory like WISE spots something deserving of more attention, SOFIA can move in for a long, slow look, while WISE continues gazing at the rest of the sky.

"WISE is designed to scan the entire sky at infrared wavelengths, gathering survey data for multitudes of objects rather than studying targeted objects in great depth," explains Marcum. "But SOFIA has time to spare for deeper studies."

To illustrate how infrared sensors can see things the human eye cannot, Marcum offers these white light vs. IR images of a warm-blooded dog and a cold-blooded lizard.

SOFIA can also do follow-up science to reap the full benefits of discoveries from Herschel's deep spatial surveys, and later, the James Webb Space Telescope's near- to mid-infrared investigations.

"Once Herschel runs out of its 3-year supply of coolant, SOFIA will be the only observatory routinely providing coverage within the far-infrared to submillimeter wavelength range. This part of the spectrum is largely unexplored territory."

"And although SOFIA covers the same part of the spectrum James Webb (JWST) covers, SOFIA is optimized for wavelengths just beyond JWST to complement its observations. SOFIA will do a bang-up job observing between the JWST and Herschel wavelength gap."

Unlike these space-based scopes, SOFIA can "head back to the barn" periodically for instruments to be repaired, adjusted, or even swapped out for new and improved science instruments - keeping pace with cutting edge science from a "mere" airplane.

Source: Science@NASA, by Dauna Coulter

Explore further: NASA Astronomical Observatory Passes Hurdle

Related Stories

NASA Astronomical Observatory Passes Hurdle

June 15, 2006

The world's largest airborne astronomical observatory has passed a technical and programmatic review that could potentially lead to the continuation of the mission.

NASA's Wise Gets Ready to Survey the Whole Sky (w/ Video)

November 17, 2009

( -- NASA's Wide-field Infrared Survey Explorer, or Wise, is chilled out, sporting a sunshade and getting ready to roll. NASA's newest spacecraft is scheduled to roll to the pad on Friday, Nov. 20, its last stop ...

Webb scope looks out of this world

January 16, 2007

The James Webb Space Telescope (JWST), the orbiting infrared observatory designed to succeed the Hubble Space Telescope, is set to enable fundamental breakthroughs in our understanding of the formation and evolution of galaxies, ...

Spitzer Finds Organics and Water Where New Planets May Grow

March 13, 2008

Researchers using NASA's Spitzer Space Telescope have discovered large amounts of simple organic gases and water vapor in a possible planet-forming region around an infant star, along with evidence that these molecules were ...

Recommended for you

Comprehensive model captures entire life cycle of solar flares

January 15, 2019

A team of scientists has, for the first time, used a single, cohesive computer model to simulate the entire life cycle of a solar flare: from the buildup of energy thousands of kilometers below the solar surface, to the emergence ...

Team discovers new way supermassive black holes are 'fed'

January 14, 2019

Supermassive black holes weigh millions to billions times more than our sun and lie at the center of most galaxies. A supermassive black hole several million times the mass of the sun is situated in the heart of our very ...

The orderly chaos of black holes

January 14, 2019

During the formation of a black hole, a bright burst of very energetic light in the form of gamma rays is produced, these events are called gamma ray bursts. The physics behind this phenomenon includes many of the least understood ...


Adjust slider to filter visible comments by rank

Display comments: newest first

Nov 19, 2009
This comment has been removed by a moderator.
not rated yet Nov 20, 2009
Curtailing vibrations from wind and aircraft must be the reason we haven't seen instruments like this before. Also, an aiming system that can keep steady "on a raft at sea" is a must.

I'd expect to see many more instruments of this kind in the near future.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.