Drake Equation: A visualization

A very nice visualization and interactive calculator for Drake Equation is at https://informationisbeautiful.net/visualizations/the-drake-equation/ 

 

Make sure you select 'lowest possible' and look at the final number ;)

(Subglacial liquid) water on Mars!

It has been long suspected that there is water on Mars. Now, there is evidence of a well-defined, 20-kilometer-wide zone under southern polar ice cap.

There are a lot of news articles about this, but here is the original manuscript from 'Science':

Radar evidence of subglacial liquid water on Mars, by R. Orosei et al.

Speck of dust... Mostly harmless...

Space.com posted a few new images from Cassini probe that highlight our relative size/position/importance in the universe.

Note that these pictures are taken inside the solar system, basically close ups. Have you seen the moon, next to the earth?

Credit: NASA/JPL-Caltech/Space Science Institute

Visit the first two links below for more eye-pooping images.

Related:

• http://www.space.com/36562-earth-moon-through-saturn-rings-cassini.html
• Cassini: The Grand Finale, mission ends in September 2017
• Mostly harmless

And, there were (or are, or will be) aliens..

Phys.org recently published an article that asks if 'we are alone' in the universe. It describes a recent astrobiology manuscript by Adam Frank of University of Rochester and 'Woody' Sullivan of University of Washington.

Here is a link to arxiv copy.

It is a slightly different take on Drake's Equation. Using the recent discovery of multiple exoplanets as a starting point, they try to find an answer to the question: "Do/did/will any other advanced technological civilizations exists/ed?"

From the abstract... "We address the cosmic frequency of technological species. Recent advances in exoplanet studies provide strong constraints on all astrophysical terms in the Drake equation. Using these and modifying the form and intent of the Drake equation, we set a firm lower bound on the probability that one or more technological species have evolved anywhere and at any time in the history of the observable Universe."

Their calculations lead to the following: "We find that as long as the probability that a habitable zone planet develops a technological species is larger than ∼10⁻²⁴, humanity is not the only time technological intelligence has evolved. This constraint has important scientific and philosophical consequences."

'Anywhere and at any time' relaxation aside, it looks like there is/was/will be more than one civilization in the known universe if the probability of technological species on a goldilocks planet is greater than 0.000000000000000000000001. Note that earth had at least one that did not reach technological level (dinosaurs) and just one that did (although sustainability is in question :).

Related: Fox News chat with Dr Frank.