Monthly Archives: August 2015

Ask Dr. Universe – Is Pluto a Planet Again?

Dr. Universe, Is Pluto a planet again or not?
-Heidi, Cincinnati, OH

Dear Heidi

It’s a big week for Pluto as NASA’s New Horizons spacecraft gets a close-up look at the distant, icy world. But first, the answer to your question: Pluto is not a planet.

Scientists called it a planet when it was discovered in 1930. They needed a name for it and an 11-year-old girl living in London at the time came up with “Pluto.” Things changed in 2006.

“Pluto is now classified as minor planet 134340,” said my friend Jessica Jones at the Washington State University Planetarium. “It was a sad day for Pluto-lovers.”

Pluto lies on the edge of our solar system, out in a region of icy objects called the Kuiper Belt. Part of the reason scientists decided to change Pluto’s classification is because it looks and behaves like other icy objects that aren’t considered planets.

Until now, scientists haven’t really been able to get a good look at Pluto. But after a nine-year journey, NASA’s New Horizons spacecraft will pass Pluto this week.

The spacecraft has already taken a few pictures of the surface. We now know the surface is reddish-brown and has some strange dark spots, Jones said.

My friend Katie Cooper is a Washington State University professor. She’s an expert on the geology of Earth and objects out in space. She said New Horizons’ flyby of Pluto once again highlights the question of what makes a planet. It has also made your question a very popular one again.

“And this is a good question,” Cooper said. “It may seem like scientists arguing over words, but good classifications help us build good models for understanding our solar system and how it was formed.”

She told me the International Astronomical Union has three rules for planets. First, it needs to orbit around the Sun.

“Pluto has got this down,” Cooper said.

Second, it needs to be massive enough for its gravity to pull it into a spherical shape. This is the rule sparking a new debate as we’ve seen new pictures of Pluto, Cooper explained.

“We’ve known it’s round for ages,” Cooper added, “but the new images just make it seem so planet-like.”

Even if it orbits the sun and it is round, planets need to follow one last rule. They have to “clear the neighborhood.” They must be big enough to knock other bodies out of their orbit. This is where little Pluto fails. It is hanging out in Neptune’s chilly orbit. Some other icy objects from the Kuiper Belt are in the orbit, too.

“Some scientists like to point out that other established planets also don’t meet all three criteria, including the Earth, because these planets share their orbits with asteroids,” Cooper explained.

Still, Cooper said because Pluto doesn’t meet this last rule, it means the astronomical union probably won’t put Pluto back into the “good graces of planet-hood” anytime soon.

Sincerely,
Dr. Universe

Have a question? Ask Dr. Universe. You can send her an e-mail atDr.Universe@wsu.edu or visit her website at AskDrUniverse.com.

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Editorial – Who Should Pay for Roads?

Who should pay for roads?

Some would say the rich should pay for the roads, or farmers, or teachers, or bricklayers, or anyone but themselves. The fact is, somebody has got to pay and I believe the people who use the roads should pay for their construction and maintenance. A practical way to do that is with a per gallon tax on fuel. The more you use the roads the more fuel you burn and the more you pay. Heavier vehicles are harder on the roads and burn more fuel and therefore would pay more. The lighter vehicles are easier on the roads and they use less fuel and would pay less. All vehicles using the roads should pay the same rate per gallon. Trucks should not pay less per gallon than cars. All electric and alternative energy cars could pay a higher registration fee so that their cost is comparable with the average car of that weight.

The per gallon taxes can be adjusted regularly to cover the expenses required to maintain the roads. All funds raised through the per gallon taxes should go for building and maintaining the roads. None should go toward mass transit, trains, trolleys, etc. Those forms of transportation should find their own funding. A special non-political committee could be set up to keep the Department of Transportation from making unauthorized or unwise decisions on how to spend these funds.

The cost of registering and licensing vehicles should be determined according to the actual cost to the government of doing that. Registration and license plates should not finance road maintenance, except in the case of cars that don’t use petroleum fuel. Many people struggle each year to pay the cost of registering and licensing their vehicle and some may use the roads very little. It’s not fair to them to mark up the cost of registering and licensing their vehicle to pay for road maintenance that’s not proportionate to their use.

If all funds from a per gallon gas tax are used for roads, and not for something else, most reasonable people will not object to that method of funding our roads. The price of fuel fluctuates so irrationally that a per gallon road maintenance tax would be unnoticeable at the pump. We would all be paying for our roads as we used them.

If you agree with this, let your state representatives know about it. If you don’t agree, offer a better and fairer plan and let us all know about it. Please don’t suggest taking money away from other programs.

Ron Cooper
4491 E. Pontaluna Rd.
Fruitport, MI 49415