@ Johns Hopkins University
Diversions
“What Happens When You Stick Your Head Into a Particle Accelerator”
Feb 22nd
From Today I Found Out:
The beam itself measured 2000 gray as it entered Bugorski’s skull and about 3000 gray when it exited on the other side. A “gray” is an SI unit of energy absorbed from ionizing radiation. One gray is equal to the absorption of one joule of radiation energy by one kilogram of matter. An example where this is commonly used is in X-rays. For reference, absorption of over 5 grays at any time usually leads to death within 14 days. However, no one before had ever experienced radiation in the form of a proton beam moving at about the speed of light.
I’m posting this out because it immediately made me think of the interview we did with Dr. DiRuggiero for last week’s 365 Days of Astronomy podcast:
The organism we’re working on at the moment is Halobacterium. They’re fairly resistant to radiation. We measure the resistance to radiation as the D10, which corresponds to the radiation doses for which 10% of a population survive. So the D10 of the organism, that is called the wild type. The regular organism is five kilo Gray—that’s measured radioactivity—which is pretty high. This is 5000 Gray, and humans are killed by five Gray. Those survive 5000 Gray; humans died with five Grays.
The cost of a newly discovered planet
Feb 9th
I get forwarded stuff. A forward I got today is for a week-old BoingBoing post about Greg Laughlin’s “exoplanet valuation” equation. Laughlin is essentially trying to find a way to quantitatively compare the importance of each exoplanet discovery. In this case, he’s trying to put it in terms of dollars and cents. I don’t see where on his site he does the derivation for the equation, and I haven’t tried running any of the numbers yet (I’m still looking for a complete list of all 1200 new candidates), but the BoingBoing post says that so far:
At the time, the exoplanet Gliese 581 c was thought to be the most Earth-like world known beyond our solar system. The equation said it was worth a measly $160. Mars fared better, priced at $14,000. And Earth? Our planet’s value emerged as nearly 5 quadrillion dollars. That’s about 100 times Earth’s yearly GDP, and perhaps, Laughlin thought, not a bad ballpark estimate for the total economic value of our world and the technological civilization it supports.
The BoingBoing link breaks down the equation, but you can find Laughlin using it everywhere on his blog.
Hunt new planets in your pajamas
Jan 10th
Veselin sent this out to the email list a few weeks ago. PlanetHunters.org is an offshoot of the Galaxy Zoo project and a fun way to spend a few minutes (or hours) looking at light curves. Check out their introductory video:
Welcome to Planet Hunters from The Zooniverse on Vimeo.
The Original Bad Boy Of Science, Tycho Brahe, turns 464 today!
Dec 14th
Happy birthday, Tycho Brahe! 464 years ago The Man With The Golden Nose was born, and the world was never the same again. Has there ever been anyone in the history of science who’s life has been as colorful as Tycho Brahe? Did you know his body was exhumed last month for forensic testing to determine once and for all whether or not he was poisoned with mercury? This sparked a lot of interest in his biography, and his name was all over the news for a couple of weeks. Here’s three of the more interesting articles posted last month.
Was Tycho Brahe poisoned? 16th-century astronomer exhumed–again
There is no shortage of lore surrounding Tycho Brahe. For starters, the 16th-century Danish astronomer famously lost part of his nose at age 20 in a duel with another nobleman and thereafter wore a metal prosthesis on his face. Then, take this bizarre snippet from an eponymous 1890 biography of Brahe by J.L.E. Dreyer:
“Two other inmates of Tycho’s house may also be mentioned here. One was a maid of the name of Live (or Liuva) Lauridsdatter, who afterwards lived with Tycho’s sister, Sophia, and later was a sort of quack-doctor at Copenhagen where she also practised astrology, &c. She died unmarried in 1693, when she is said to have reached the ripe age of 124. The other was his fool or jester, a dwarf called Jeppe or Jep, who sat at Tycho’s feet when he was at table, and got a morsel now and then from his hand. He chattered incessantly and, according to [Brahe's assistant] Longomontanus, was supposed to be gifted with second-sight, and his utterances were therefore listened to with some attention.”
Later in his life, as court astronomer to Emperor Rudolph II in Prague, Brahe collected some of the best observations of his day for the positions of celestial bodies in the sky, which his successor, Johannes Kepler, would later publish as The Rudolphine Tables. To top it off, Brahe died at age 54 after, as the story goes, he stayed at the table too long without relieving himself during a formal dinner, possibly bursting his bladder in the process.
The crazy life and crazier death of Tycho Brahe, history’s strangest astronomer
Brahe inherited a great deal of wealth from his foster father Jørgen, who died in 1565 when saving the King of Denmark from drowning…a rather different royal death than the one Tycho might later have experienced. Brahe is thought to have possessed as much as 1% the entire wealth of Denmark, and five times that much was spent by the Danish government on Brahe’s astronomical research.
He lived in a castle, where he kept a rather unusual group of regular entertainers. He employed a little person called Jepp, who Brahe believed possessed psychic powers. Jepp was his court jester, and spent most dinners under the table. It’s probably best not to speculate on just why Brahe preferred that arrangement. Then there was Brahe’s elk, a tame beast that Brahe kept as a prized pet. The elk met a rather bizarre end, reportedly drinking a lot of beer while visiting a nobleman on Brahe’s behalf, after which it fell down the stairs and died. Yes, that entire sentence was about an elk.
I’ve heard stories that the elk got a state funeral.
Murder! Intrigue! Astronomers?
It’s “Amadeus” meets “Da Vinci Code” meets “Hamlet,” featuring a deadly struggle for the secret of the universe between Tycho, the swashbuckling Danish nobleman with a gold-and-silver prosthetic nose, and the not-yet-famous Johannes Kepler, his frail, jealous German assistant. The story also includes an international hit man, hired after a Danish prince becomes king and suspects Brahe of sleeping with his mother (and maybe being his father!).
For comic relief, there’s a beer-drinking pet elk wandering around Tycho’s castle, as well as a jester named Jepp, a dwarf who sits under Tycho’s table and is believed to be clairvoyant.
“Conditions resemble those on the Earth….”
Apr 27th
By way of io9.com, I found this post about a New York Times Magazine article from March 24, 1912. It’s an interview with a zoologist, Edmond Perrier, and it seems as though he had some incredible things to say:
The dampness of the atmosphere on Venus favors the growth of ferns. The development of flowers from the more primitive forms of plants must be slow and probably has not yet been accomplished on Venus. This lack means the absence also of bees, butterflies, perhaps of ants and of other insects which depend partly or entirely on flowers for their food.
Venus, then, is the home of insects like grasshoppers, or dragon-flies, or roaches, grown to an enormous size; of large batrachians, frogs as big as our cows, of innumerable and gigantic reptiles like those which once filled our earth, ichthyosauri, pterodactyls, iguanodons. Man is absent; indeed the race of mammals may not yet have appeared, in even the humblest form.
Clearly this is inspiration for the Rocket To Venus around the corner in Hampden.
“Let’s say you’re the first human ever to make alien contact…”
Apr 19th
By way of io9.com, a rather thorough graphic on dealing with being the first human ever to make alien contact. The comments to the io9 post also have this Popular Mechanics article from 2004, When UFOs Arrive What Will You Do? I wasn’t able to find the original article in the Popular Mechanics archive, so I had to grab the link from one of the many crank sites that can be found on the interwebs instead.

