Are people really becoming morons like this?
There is no such value, no possible way to calculate it, and if even there where, price-tagging the universe kinda means that we own it.

Which, you know, we don’t. Kind of the opposite.
The Universe owns us. A car doesn’t try to sell the plant that made it.

It would be rather intriguing to see this euation stretched out a bit to encompass projected costs of transportation, etc. to help map out the economics of terraforming, colonizations, etc.

Very interesting work–Lee Billings has given us all a lot to think about. Thank you sir!

It remains to be seen what are the odds of two habitable planets in on system, but it has almost certainly happened somewhere. I would guess that in order to be “habitable”, a planet would have to have photosynthetic life, at low levels at least, to scrub the atmosphere and crank out the required oxygen.

“Men are from a planet worth significantly more than the planet women are from, but still a planet that is not really worth all that much.”

Return on investment / value placed on planets discovered, and their potential as expressed in Monetary terms: Variable ( see article above ;) )

The increasing awareness that we may not be alone in the Cosmos: Priceless

First a minor correction: “the mass ratio of the planet to the star, raised to the 1/3rd power.” The way the equation is written, Greg actually means it’s the ratio of the mass of the *star* that has the planet in question to the Sun’s mass, so that one favors lower mass stars.

To the above comment, I’d add that while Kepler seems to be telling us that low mass stars are a good place to find for Earth *sized* planets, Greg is playing a little loose with the phrase “Earth-like”. It’s true that we skew our searches towards lower mass worlds, and with good reason, but low mass stars also pose some unique problems for the planets around them. Because these stars are so cool, their habitable zones lie very close to the star– you can think of the planets being huddled around the embers of a campfire to stay warm. However, cool stars are what we call “active”, meaning they have lots of flares. Flares are a problem because they emit high energy radiation (like X-rays and UV light) that can harm life as we know it, and can change the planet’s atmosphere over time. On the one hand, these flares become less common with age– Greg includes a bias towards older stars to account for this, in part. On the other hand, low mass stars may also flare for a longer portion of their youth than stars like our Sun.

To me, one of the big questions is what flares do to planetary atmospheres– we know that over time, getting smacked again and again by stellar flares can cause the atmosphere not only to change its composition, but to actually erode, so you could take a world that was potentially habitable and end up with a dry, barren rock. Now, that’s not an inevitable outcome– there are ways a planet can keep its atmosphere over time, and we are still learning about how flares affect planets generally speaking. I don’t think it’s a dealbreaker for habitability, I just want to point out some of the complexity hiding in those simple terms.

I’d also like to point out that the impact of a discovery devaluing with time from the Kepler launch leaves out an important population of planets: ones like ours. Because it takes at least 3 transits to find a planet, and because planets that are in 1 year orbits around their stars (i.e. the habitable zone for stars like our Sun), it will take roughly 4 years for Kepler to detect planets in orbits like ours just because of how infrequent the transits are. I am guessing finding a small planet in an Earth-like orbit around a Sun-like star would be a pretty big deal.

Lastly, and perhaps most importantly, there is a big missing term in Greg’s equation: UNCERTAINTY. Where are the error bars on those dollar values? It may score high on the hype-o-meter, but remember: the least habitable planet is the one that is not actually there.

* Mainly because it’s orbiting an M5 flare star and has sulfur dioxide oceans.

How much for the planet with sexy Orion slave girls?

Your analysis is precisely the sort of thing I wanted to foment with the post, and I’m guessing Greg is of a similar mind. The point is to get people talking about confirmed and candidate planets in an objective way that quantifies what’s known and unknown about them. The more context we can squeeze out of these little dips in light curves, the better.

I just assembled a simple online calculator for this equation.
See it at:

http://www.hajnalmarton.com/planetcalc

Just write the values in the fields, then press “Calculate value”.
Send me a mail to hajnalm (at) gmail (dot) com if you have any questions, suggestions or remarks.
Have fun!