Scientists to Eye Potential 'Comet of the Century' with Balloon Mission

This story was updated 5:34 p.m. EDT.

Scientists are working to loft science gear by balloon to observe the fast-approaching Comet ISON, which could be one of the brightest comets ever seen when it blazes through the inner solar system this fall.

The project, called Balloon Rapid Response for ISON (BRRISON), aims to get high-quality views of Comet ISON, which experts say could shine as brightly as the full moon when it makes its closest pass by the sun in late November.

The sky-high BRRISON project also hopes to demonstrate that important planetary science questions can be addressed with a balloon platform, researchers say. It will be the first planetary-science balloon mission since 1963, when a Stratoscope II balloon lifted off to observe planets, stars and galaxies. [Photos of Comet ISON in Night Sky]

A large helium-filled balloon will tote a gondola packed with a telescope and other equipment to near space, soaring up to 120,000 feet (36,576 meters) altitude  — almost 23 miles (37 kilometers) above the Earth. The BRRISON balloon's gondola will carry infrared and near ultraviolet/visible imaging gear, along with fine steering mirror technology to obtain high pointing stability.

BRRISON is to be launched from the Columbia Scientific Balloon Flight Facility at Fort Sumner, N.M., in the September-October timeframe on a one-day observing trek.

Super pressure

The BRRISON project, which is being sponsored by NASA, The Johns Hopkins University Applied Physics Laboratory (APL) and the Southwest Research Institute, is moving fast, because time is of the essence.

Comet ISON — officially designated C/2012 S1 (ISON) — was just discovered in September 2012, by Russian amateur astronomers Vitali Nevski and Artyom Novichonok.

"We will be going from discovery of Comet ISON to start of the launch window for the balloon within one year," said Andrew Cheng, BRRISON principal investigator and chief scientist in the Space Department at APL in Laurel, Md.

Work on BRRISON has been underway since early February, Cheng told SPACE.com. "It's the fastest I've ever run in my life, he said. "From confirmation to start of the launch window, we will have six months. That's mighty fast, even for us, but the comet won't wait."[Amazing Comet Photos by Skywatchers]

Thin atmosphere

Instrument-carrying high-altitude balloons can deliver cost-effective science, a high priority in this era of tighter budgets, said BRRISON team member Eliot Young, a principal scientist at Southwest Research Institute in Boulder, Colo.

Earth's atmosphere is thin up at BRRISON's observing atmosphere, Young said.

"You can compete with the Hubble Space Telescope for getting sharp images, but at a tiny fraction of the cost," Young told SPACE.com.Young told SPACE.com.he Hubble Space Telescope for getting sharp images, but at a tiny fraction of the cost,"to 140,000 feet al The science equipment is divided up into two benches, "stacked like a wedding cake," he added.

Along with Comet ISON observations — depending on expected duration of the balloon flight — other celestial targets may come into focus, such as Asteroid Elektra, Comet Encke and two bright double stars in the handle of the Big Dipper, Young said.

Challenges

With the clock ticking, and Comet ISON clicking off mileage, the BRRISON team faces some challenges,  Young said, such as matters of thermal control and the pointing accuracy of science-gathering instruments in the gondola.

"It's very similar to hanging an SUV from a 300-yard cable," Young said. "The good news is that wind disturbances in the stratosphere are, by and large, pretty benign."

With launch day only a few months away, the anticipation is building. "Balloon liftoffs are magical moments," Young said. The race to get BRRISON off the ground and get Comet ISON in view "is stressful ... but fun," he said.

"BRRISON is absolutely unique in terms of what we're going to measure at the comet. There's nothing else that can do it right now," Cheng said. "There are space telescopes, but none of them happen to be in the right place at the right time ... and there isn't enough time to build something new. With a balloon, it's doable."

Sungrazing comet

An Oort Cloud comet believed to be making its first trip to the inner solar system, Comet ISON's perihelion — or closest approach to the sun — occurs Nov. 28, when it's projected to skim about 730,000 miles (1.2 million km) above the solar surface. There's no guarantee ISON will survive this perilous passage intact, but BRRISON will observe the comet before perihelion.

BRRISON is geared to measure carbon dioxide and water, primary cometary volatiles. Found as ices in a comet’s nucleus, they drive cometary activity. Scientists want to know whether the abundances of these volatiles are related to where comets formed, what they formed from and how they evolved.

Cheng said that most of the data gleaned by BRRISON will be recorded onboard and analyzed after landing.

"We'll also have immediate downlink data so we'll know on the spot how things are working," he said.

Target of opportunity

Comet ISON is an important target of opportunity, Cheng said, to study volatile-rich material from the epoch of planet formation; to learn how comets work; and to find clues to the origins of the solar system.

Furthermore, BRRISON will develop and demonstrate gondola and payload systems for a balloon-borne platform designed to achieve a range of planetary science objectives, Cheng added. BRRISON's gondola is designed to protect the payload during nominal recovery back on the ground, he said, enabling re-use.

"We're making new observations of an object that has never been observed before in the wavelengths we’ll have. We've got to learn something new and exciting," Cheng said.

Editor's note: If you capture an amazing photo of Comet ISON or any other night sky sight that you'd like to share for a possible story or image gallery, please contact managing editor Tariq Malik at spacephotos@space.com.

This story was corrected to reflect the fact that the BRRISON mission will fly on a Zero Pressure balloon, not a Super Pressure balloon.

Leonard David has been reporting on the space industry for more than five decades. He is former director of research for the National Commission on Space and is co-author of Buzz Aldrin’s new book "Mission to Mars – My Vision for Space Exploration" out in May from National Geographic. Follow us @Spacedotcom, Facebook or Google+. Originally published on SPACE.com.

Copyright 2013 SPACE.com, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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NASA Spacecraft Snaps New Photo of Potential 'Comet of the Century'

A NASA spacecraft scanning for the most powerful explosions in the universe has captured a photo of Comet ISON, an icy wanderer that could potentially dazzle stargazers when it swings close to the sun later this year.

NASA's Swift satellite, which is typically used to track intense gamma-ray bursts from distant stars, photographed Comet ISON on Jan. 30, with the space agency unveiling the photo today (March 29). By tracking the comet over the last two months, Swift has allowed astronomers to learn new details about how large the comet is and how fast it is spewing out gas and dust.

"Comet ISON has the potential to be among the brightest comets of the last 50 years, which gives us a rare opportunity to observe its changes in great detail and over an extended period," said Lead Investigator Dennis Bodewits, an astronomer with University of Maryland at College Park (UMCP) who helped obtain the new image.

Some astronomers have predicted that ISON could be the "Comet of the Century" when it makes its closest approach to the sun in late November. But a recent analysis found that the comet is not brightening as expected, and may have a ways to go to meet such expectations.

Comet ISON was first discovered in September 2012 by Russian astronomers Vitali Nevski and Artyom Novichonok using the International Scientific Optical Network (ISON) located near Kislovodsk. The comet's official designation is Comet C/2012 S1 (ISON). [See more photos of Comet ISON]

Swift's Comet ISON view

Bodewits and his university colleagues teamed up with the Lowell Observatory in Flagstaff, Ariz., to capture new views of Comet ISON using the Swift spacecraft. The satellite's Jan. 30 photo shows the comet as a bright, fuzzy white ball. At the time, Comet ISON was about 375 million miles (670 million kilometers) from Earth and 460 million miles (740 million km) from the sun.

"Using images acquired over the last two months from Swift's Ultraviolet/Optical Telescope (UVOT), the team has made initial estimates of the comet's water and dust production and used them to infer the size of its icy nucleus," NASA officials wrote in a statement.

Swift's observations revealed that Comet ISON is currently shedding about 112,000 pounds (51,000 kilograms) of dust and about 130 pounds (60 kg) of water every minute, an odd mismatch for such an anticipated comet.

All comets are made of dust and frozen gases that mix together to form a sort of "dirty snowball" in space, NASA officials explained. Water ice in comets typically stays frozen until the comet approaches within three times the Earth's distance to the sun, at which time the water ice heats up and changes directly into gas (a process called sublimation), creating jets of material that can brighten the comet.

"The mismatch we detect between the amount of dust and water produced tells us that ISON's water sublimation is not yet powering its jets because the comet is still too far from the sun," Bodewits said. "Other more volatile materials, such as carbon dioxide or carbon monoxide ice, evaporate at greater distances and are now fueling ISON's activity."

Currently, Comet ISON is about 5,000 times fainter than the dimmest object the human eye can see.

NASA's Comet ISON campaign

NASA's Swift spacecraft is one of several satellites and probes to observe Comet ISON as it passes through the inner solar system. The space agency has formed the Comet ISON Observing Campaign (CIOC) to make the most of the comet's visit.

On Oct. 1, the comet will pass within 6.7 million miles (10.8 million km) of Mars, and may be spotted by orbiters around the Red Planet. [Comet ISON's Path Through Solar System (Video)]

"During this close encounter, Comet ISON may be observable to NASA and ESA spacecraft now working at Mars," said Michael Kelley, a UMCP astronomer and also a Swift and CIOC team member. "Personally, I'm hoping we'll see a dramatic postcard image taken by NASA's latest Mars explorer, the Curiosity rover."

On Nov. 28 — 58 days after swing close by Mars — Comet ISON will make its closest approach to the sun, flying within 730,000 miles (1.2 million km) of the star's surface during the encounter. Several sun-watching observatories will be tracking the comet at that time, and ISON may even become visible in the daytime sky to observers who block the sun's light with their hand, NASA officials said.

The comet will make its closest approach to Earth on Dec. 26, coming with 39.9 million miles (64.2 million km) of the planet as a late Christmas present.

But whether Comet ISON will live up to its celestial hype or fizzle out in a whimper still remains to be seen, astronomers warned. The comet must still survive the approach into the inner solar system, as well as its close encounter with the sun.

"It looks promising, but that's all we can say for sure now," Matthew Knight, an astronomer at Lowell Observatory said. "Past comets have failed to live up to expectations once they reached the inner solar system, and only observations over the next few months will improve our knowledge of how ISON will perform."

Editor's note: If you snap an amazing photo of Comet ISON or any other celestial object, and you'd like to share for a possible story or image gallery, please send images and comments, including location information, to Managing Editor Tariq Malik at spacephotos@space.com.

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik and Google+. Follow us @Spacedotcom, Facebook and Google+. Original article on SPACE.com.

Copyright 2013 SPACE.com, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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