Tuesday, August 30, 2016

Why the Media Needs to STOP using "Earth Like".

If you keep up to date on science issues, you are no doubt aware of the latest exoplanet discovery. Proxima Centauri A has a Earth size planet orbiting it. It is at the right distance and right size to support liquid water. Unfortunately, the press uses the highly inaccurate term "Earth Like" to describe wolds like Proxima Centauri b. I'll explain why I feel this is a terrible term for these planets. Although it's exciting to have a nearby (40,000,000,000,000 km) That will still take a spacecraft like New Horizons 18,000 years to get there. Nearby is relative if you use ice ages as a measurement. I like the sound of 1 ice age instead of several times longer than humans have had civilization on the earth.

Credit: Jean-Luc Beuzit, et al. Grenoble Observatory, European Southern Observatory

 Exoplanets are planets that have been located outside our solar system. They are found using a number of techniques, but only a handful have been directly observed. Beta Pictoris b is a planet observed by the European Space Agency's telescopes in Chile using infrared telescopes. Beta Pictoris b is a small smudge on the photograph pictured above.  An annotated picture with the planet highlighted can be found here. That is about as close as we can get to seeing a small dot of light in another solar system. A pixel or two.

Most of the time planets are located using a method called Transit Photometry, which detects the planet by measuring how dim the star gets when it comes between us and its parent star. There are other ways of detecting exoplanets, and none of them are easy. Although we can learn a lot from the information we do gather, we aren't able to tell if a planet actually can support life, at least not yet.

With all we do know, there's a lot we don't. As I've discussed in other blogs, magnetic fields, atmosphere, and the type of star system have a lot to do with the viability of a planet supporting life. It's not enough to have the building blocks of life to have a habitable planet. What bothers me most is that people impart the qualities found on Earth to distant objects that we know very little about. Earth-size is more accurate in this case, but not Earth-like.

Earth is, as far as we KNOW, the only place where life is known to currently exist. It's thought that bacteria was once found on Mars, but we haven't found any evidence of it existing there now, or even in the distant past. Earth has life in abundance. Life has existed and survived several extinction events that have wiped out countless species over billions of years. Still this world persists in supporting life. I am certain that there are other worlds that ARE like Earth, and support bountiful life. However, people should avoid placing qualities on anything with no way of supporting that claim. To do so is sensational, inaccurate, misleading, and tabloid in nature.

No comments: