Tuesday, January 31, 2006

The Leap Days

Today, we worry about millisecond and nanosecond inaccuracies in times, but in the past, there have been discrepancies the length of days.

When Julius Caesar invented the Julian calendar, it was off by 11.5 minutes each year. Over the centuries, that small error added up so that by 1582, the Julian calendar being used by the Western Roman World was 10 days behind.

To fix the discrepancy in the Julian calendar, Pope Gregory XIII gave us leap days. However, before the Gregorian calendar could be put into place, the extra 10 days given to mankind by the Julian calendar had to be done away with.

Pope Gregory XIII then declared that the day after October 4, 1582 would be October 15, 1582. In Rome, all the days in-between never existed. There was wide-spread rioting in Rome because many Christians alive at the time felt that if their date of birth and date of death had been pre-ordained, the Pope had just shortened their lives by 10 days.

In defiance of Rome, England did not adopt the Gregorian calendar, so for nearly two hundred years it was always ten days later in Rome that it was in London.

Finally, in 1752 when England adopted the Gregorian calendar to sync itself up with the rest of the Western World, the day after September 2, 1752 was September 14, 1752, 11 days having never existed in London.

The problem this time, however, was not that people felt their lives were being shortened, but people actually were incensed to riot because they paid rent by the month and only got 19 days for their monthly rent that September. Naturally, landlords refused to make exceptions and expected October’s rent right on the first of the month.

Sunday, January 29, 2006

The Leap Second

It received some news coverage, but nothing really major. At the end of 2005, there was a leap second that was added to analog clocks to get them caught up with atomic clocks.

To understand this, you must first know that there are currently two time-keeping systems in place for the civilized world.

Analog clocks are kept and maintained by measuring the Earth’s cycle around the sun and the Earth’s rotation on it axis, just as has been done for thousands of years.

The problem with analog, however, is that each time the Earth revolves around the sun, there is an average discrepancy of a half-second each year. In addition, each day is actually not exactly as long as each other due to the pulling of the tides on the Earth’s rotation which cause fluctuations of milliseconds.

Realizing that there was a problem with this analog time keeping, scientists developed a new method called the atomic method some 40 years ago. The atomic method uses the measurement of the extremely accurate and precise cycle of an atom of the isotope cesium-133.

In one second, the atom cycles 9,192,631,770 times. This cycle is constant, never varying and means that a half-second variance like the one that occurs in analog time each year, occurs only once every 10 million years in atomic time.

Since 1967, because of the variance in the two time-keeping methods, mankind has had to add a leap-second to analog time 23 times to ensure that the analog clocks and the atomic clocks are in sync to the tune of no more than a 0.9 second variance.

Why is it important to keep the clocks in sync? Well, if we stopped adding the leap seconds today, in the year 5000, the sun would be right overhead at noon, but your atomic clock would say it was getting close to midnight.

So, what’s the problem with leap seconds? Well, remember Y2K? There are some folks that believe if we keep stopping our atomic clocks for one second intervals every couple years, it will cause wide-spread system failures in the flight control, traffic control, power grids, mobile phone networks and defense systems that are all tied to atomic clocks.

For example, if a GPS satellite sends a signal a millisecond early or late, it can provide a reading that is inaccurate by 100 miles. You do not want a ballistic missile being 100 miles off its target.

So, for now, while scientists debate the best method, atomic clocks continue and the old-time Earth-monitoring analog time continues, both being continually checked against the other.

Monday, January 2, 2006

What Can Congress Do?

A senator can have a corporate jet make a special flight just for them and reimburse the company for one seat's worth of first-class airfare, not the actual cost of the flight. See how a company can donate to their senator through this airfare reimbursement?

A representative cannot take travel expenses directly from a lobbyist, but can take expenses from a charity or other organization with a lobbyist on its board. This means that the lobbyist cannot give travel expenses to the representative, but the lobbyist's charity can.

Corporations cannot contribute to a politician’s campaign fund, but the corporation can contribute to a charity that a politician is associated with. These charitable donations do net even need to be reported by the politician.

Senators, representatives, and their staffers cannot take a single gift, including food and entertainment, worth $50 or a collective of gifts worth $100 from a single person. If that person, however, is a "personal friend" of the representative, that $100 increases to $250. Because of these limits, the owner of the NBA Wizards and the NHL Capitals has set the price of club tickets at $49.50.

A lobbyist can provide up to $49.99 worth of food per person for a representative and staff for late-night sessions, provided the lobbyist has no "direct interest" in the legislation they are working on that particular night.

Senators and representatives are allowed to use campaign funds to defend themselves in bribery investigations that are related to their office.