NEW YORK (CNN) -- CNN Money's Maribel Aber has your top business and financial news on this Tuesday, October 8.

4 debt ceiling scenarios freaking out traders
What could go wrong on trading desks if the U.S. defaults on its debt? A lot. Government officials used to see it as part of their job to calm the markets. Not anymore. Last week, President Obama and Treasury Secretary Jack Lew both said they thought Wall Street wasn't freaking out enough about the possibility of a debt ceiling default. Right now, most of Wall Street appears to be betting that a deal will get done. But on some trading desks, the possibility of a default is starting to sink in. No one knows what it means, but everyone agrees it would be bad.

A 1-month shutdown: $50 billion economic blow

If the week-long government shutdown stretches to a month, it would mean a $50 billion blow to the U.S. economy. That estimate is actually $5 billion lower than the initial estimate of Mark Zandi, chief economist for Moody's Analytics. He lowered his forecast after the Defense Department recalled nearly half of 800,000 federal employees furloughed last week, and it appeared Congress would quickly approve a measure to pay other furloughed workers retroactively.

Ultra-cheap airfares of little use? Not for airlines
It might have seemed that some airlines had gone completely nuts over the last couple of weeks. Southwest Airlines recently ran television ads that touted $69 fares, followed by promotions from Virgin America for fares starting at $59. Not to be outdone, Alaska Airlines peddled $49 fares - a deep discount compared with the average one-way domestic fare of about $190. These too-good-to-be-true deals usually come with a slew of restrictions, making them almost useless for most travelers. But industry experts say the fares make plenty of sense to the airlines.

New $100 bill to debut Tuesday
The new $100 bill will make its debut Tuesday, several years later than originally planned. The bill was originally due to reach banks in 2011. But three years ago the Federal Reserve announced that a problem with the currency's new security measures was causing the bills to crease during printing, which left blank spaces on the bills. The bill's belated debut has nothing to do with the government shutdown, since the Fed's budget is not included in the current congressional appropriations stalemate.

Read or Share this story: