That engineer told me something that would later become symbolic of NASA's Challenger failures.

NPR: Challenger: Reporting a Disaster's Cold, Hard Facts

It wasn't long after the Challenger explosion that word of a pre-launch argument leaked out.

NPR: Challenger: Reporting a Disaster's Cold, Hard Facts

Hope speaks to the unknown and it is always the challenger who represents the unknown.

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"If you can't keep a lid on it, don't go to it, " Challenger advises.

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In Rhode Island, Republican Senator Lincoln Chaffey faces a tough battle with a conservative challenger.

NPR: For Santorum, Race Momentum Swings

These two banks alone have shed more than 5, 500 workers since January 1, Challenger, Gray notes.

FORBES: Prediction: Financial Services Will Be the Loser in Tomorrow's Jobs Numbers

His Democratic challenger has already started airing campaign ads that refer to the scandal.

NPR: With Election Looming, GOP Distracted by Foley

This was mystifying to the Democrat challenger Jimmy Carter and an audience of millions.

FORBES: Politics, U.K. Style

The challenger's camp has not explained how it intends to proceed with the recount demand.

NPR: Maduro Certified As Election Winner Amid Protests

Challenger Henrique Capriles' aides accused Chavista loyalists in the judiciary of putting them at glaring disadvantage.

NPR: Venezuela's Choice: Chavez Heir Or Fresh Start

The Challenger disaster had made us that much more committed to our space program.

FORBES: Space Shuttles and Motorcycles

"She'll get air, " he confides about the unsuccessful challenger for the America's Cup in 1934.

FORBES: Two Sheets to the Wind

One major challenger is Novartis (nyse: NVS - news - people ).

FORBES: Magazine Article