Podcast: Play in new window | Download (Duration: 1:17:02 — 35.3MB)
Other Earths, Good Old Days, Touchy Crocs, Caffeine For Good!, Navel Gazing, Mucus Toothpaste, The End of India, And Much More…
Disclaimer, Disclaimer, Disclaimer!!!
This Week in Science… coming up next!
BLair’s Animal Corner
Touchy Crocodilians
Despite their heavy armored skin, crocs can be very sensitive to touch along their jaws. Scientists have often wondered what the tiny raised black dots along the jawline of crocodilians are used for, and new research indicated it is not to detect oil, salinity or magnetism, but the are extremely delicate touch receptors, more sensitive than human fingertips. So, when that crocodile bites you, he knows exactly what he’s biting and how hard – comforting? Maybe not…
Get a free audiobook at Audible.com!
Caffeine – the new antidepressant?
Caffeine enhances the processing of positive words, but not neutral or negative ones. So it makes you more productive AND gives you a better self-image. Sign me up!
If you love TWIS, please support us by donating below:
12:20 Seven times the mass? That’s a lot of gravity!
One again, Justin, you don’t know what you’re talking about! The gravity happens to be quite small.
Remember, the force of gravity depends on not only the mass, but also the square of the radius!
The HD 40307 system has very low metalicity, so its planets are mostly gas.
These planets will have small iron cores and low mean density, like Neptune and Uranus.
Taking the higher of the two densities, we can calculate the radius of HD 40307 g.
First, we find the volume of the planet: 2.375 * 10^22 m^3
Then we can find the spherical planet’s radius: 3.825 * 10^7 m
Now, we can find the gravitational acceleration at the surface: 19% Earth’s Gravity!
Though for us, this insubstantial gassy surface wouldn’t be a very fun place, even with such low gravity.
17:30 They’re looking for alpha particles…
No, they aren’t. The Wired article is just wrong. These are NOT alpha particles!
Alpha particles are Helium nuclei, so obviously, they can’t be emitted by Hydrogen atoms! Duh!
The paper looks at redshift of the Hydrogen alpha emission line.
Since Hydrogen is so abundant, this prominent emission line is quite easy to study.
It’s just light.
18:00 We probably only have a couple billion more years of star formation left.
Again, the article is simply wrong.
There is nothing in the paper to suggest anything of the sort.
New stars will continue to form for trillions of years hence.
However, the overall population of active stars will not increase much, from now.
Instead, peak luminosity will be reached in another few billion years.
At the time of peak luminosity, there will be 5% MORE stars shining than there are today.
Long, long after peak luminosity, stars will continue to die, and be born.
The stars birth rate will simply decline, and be overtaken by the death rate.
You guys are too easily suckered, because you never read the original paper!
Hmm, I wonder why moderation of my posts takes so long?
All posts are moderated when I get to it. I don’t single yours out for special treatment, if that is what you are implying.
Yes yes, Physics Police you are a most welcome poster here… keep the good corrections coming!