Tag Archives: science

We are not alone — okay, maybe we are

The universe, [Stephen Hawking] points out, has 100 billion galaxies, each containing hundreds of millions of stars. In such a big place, Earth is unlikely to be the only planet where life has evolved.

“To my mathematical brain, the numbers alone make thinking about aliens perfectly rational,” he said. “The real challenge is to work out what aliens might actually be like.”

The Times is overstating what Stephen Hawking said, but nevertheless, he’s arguing from incredulity. Just because the number of galaxies and stars is large doesn’t guarantee there are aliens. It doesn’t even make it likely. There’s simply no way to know at present how likely it is that we are alone.

As for the rest of the argument, it’s not much better. Any species of alien that has mastered interstellar travel will have perfected nanotechnology. Resource limitations won’t be a problem for them, unless you’re talking about pure raw material such as carbon. They’re not going to be running around the galaxy raiding planets for hydrocarbons.

Scientific Illiteracy Sucks

Researchers have found two objects orbiting stars that have unexpected characteristics. As reported by the Associated Press, the objects are, “…too hot to be planets and too small to be stars.” The objects don’t appear large enough to be stars, but they’re hotter than the stars they orbit — 26,000 degrees Fahrenheit according to the article (that’s almost 15,000 degrees Kelvin).

The author gets into trouble when he/she tries to explain that temperature in terms the reader can understand, saying, “That’s hot enough to melt lead or iron.” There are so many things wrong with that sentence it hurts.

First, that’s like saying the International Space Station is higher up than airplanes fly. It’s true, but it’s a ridiculous comparison: everything melts at 26,000 F — Tungsten Hafnium Carbide has the highest known melting point at less than 8000 F.

Second, the two materials chosen for comparison have very different melting points. Iron holds out until 2800 F, but Lead melts at just over 600 F — that’s something you can achieve on your back yard barbecue, or with a fresnel lens.

Therefore the equivalent metaphor for height would be something like, “The International Space Station is higher than a 747 and a Cessna.”

So how should they have described the temperature? It may be boring, but it’s more than twice as hot as the surface of the sun.