Stories tagged History and Nature of Science


Historic 1919 total solar eclipse: Negative and positive photographic plates of one of the photographs taken during Sir Arthur Eddington's expedition to Principe Island in May of 1919.
Historic 1919 total solar eclipse: Negative and positive photographic plates of one of the photographs taken during Sir Arthur Eddington's expedition to Principe Island in May of 1919.Courtesy Public domain
Tomorrow marks the 90th anniversary of an historic total solar eclipse that confirmed aspects of Albert Einstein’s theory of general relativity.

Einstein hypothesized that stars calculated to be behind the edge of the solar disk should be visible due to bending by the sun’s massive gravitational field, much like the way a camera lens or magnifying glass bends light to focus it into a precise pinpoint. But because of the sun’s tremendous blinding light, the predicted bent starlight would only be observable during a total solar eclipse when the moon blocked out the solar disk.

So, to test Einstein’s theory, British scientist Sir Arthur Eddington set out on an expedition in early May of 1919 for the island of Principe off the west coast of Africa. His purpose was to photograph the total solar eclipse predicted to take place there on May 29th and either prove or disprove Einstein’s theory.

Photographs taken by Eddington during his historic expedition successfully captured Einstein’s predicted phenomenon and helped the theory of general relativity gain worldwide acceptance.

Eclipse that Changed the Universe - Einstein's Theory of Relativity
1919 Eclipse and General Relativity
Relativity and the 1919 Eclipse
Eclipse negative and illustration of gravitational bending


I stumbled across this story on BBC news. A medieval church was discovered by a team of archaeologists from Lampeter University. The site was discovered in a city that is apparently unpronounceable by humans. A geophysical survey was used to detect the foundation of the church in Swyddffynnon, Wales. Given the amount of material, possible other buildings and additional evidence of human activity found it has been speculated by the team that this may be the site of a medieval village.


Not to freak y'all out, but did you know that germs are on everything you touch? Using a special powder called Glo Germ (get it here) you can actually see how germs spread from one thing to another. It will make you want to wash your hands more often. (And the CDC recommends washing your hands frequently. In fact, why don't you go wash up right now?)

Scrub 'em: Use soap and water, and wash for 20 seconds. That's about the time it takes to sing the "Happy Birthday" song twice.
Scrub 'em: Use soap and water, and wash for 20 seconds. That's about the time it takes to sing the "Happy Birthday" song twice.Courtesy mitikusa

Goal: to observe how germs are spread
Age level:: 3 and above
Activity time: 2 - 5 minutes
Prep time: 5 minutes

Materials needed:

  • Glo Germ powder
  • Toys or common household/school/office objects to "spike" with germs
  • UV lamp or detector box


  1. Sprinkle Glo Germ powder on your objects.
  2. Arrange them somewhere where others can handle them.
  3. Plug in UV lamp, but don't turn it on.

Encourage others to pick up and play with the objects. Ask them what they know about germs.

  • Do you know where microbes are found?
  • Do you know what a microbe/germ is?
  • Do you know what illnesses are caused by germs?
  • Do you know the best way to avoid getting sick because of germs?

After the discussion, tell them that, as part of an experiment, you've put "pretend" germs on one or some of the objects they may have touched today. Switch on the UV lamp: what glows?

Reinforce the fat that the Glo Germ powder is just to simulate germs. It won't make you sick. You can get rid of the germs by washing your hands. In fact, encourage your audience to wash their hands and then hold them under the UV light again.

(On the other hand, remember that not all germs are bad. Exposure to some germs is thought to protect people against asthma and allergies or colitis, and overuse of antibacterial products leads to antibiotic resistance and superbugs as well as potential damage to the environment.)


A research group led by Dirk Brockmann at Northwestern University has created a computer model that predicts the spread of the 2009 H1N1 influenza virus in the US. (It uses a complex set of mathematical equations to describe the movement of people and virus.)

How can you track and predict the movement of something so small?: Follow the money, of course! (This is a colorized negative stained transmission electron micrograph (TEM) showing some of the ultrastructural morphology of the A/CA/4/09 swine flu virus. Got that? Good.
How can you track and predict the movement of something so small?: Follow the money, of course! (This is a colorized negative stained transmission electron micrograph (TEM) showing some of the ultrastructural morphology of the A/CA/4/09 swine flu virus. Got that? Good.Courtesy CDC/C.S. Goldsmith and A. Balish

(Brockmann was a guest on Minnesota Public Radio's Midmorning show today, and you can listen to it online.)

The good news is that, based on what we know now, and assuming that no one takes any preventive measures, we could expect to see some 1,700 cases of swine flu in the next four weeks. Because of the preventive measures being taken wherever a suspected case of H1N1 flu has popped up, we should actually see fewer cases. (You can see Brockmann's models here.) That's lousy if you're one of the folks who picks up the virus, but not a devastating number of cases. Of course, this is a rapidly developing, fluid situation, and things may change. Still, tools like Brockmann's model help to ensure that emergency supplies and other resources get to the places likely to need them most before they're needed.

Professor's Computer Simulations Show Worst-Case Swine Flu Scenario from Northwestern News on Vimeo.

Don't have faith in computer models? Well, a second research group at Indiana University is using another model, with different equations, and getting very similar results. That's a pretty good indication that the predictions are reliable.

You might remember Brockmann from a 2006 study that used data from, a site that allows users to enter the serial numbers from their dollar bills in order to see where they go, to predict the probability of a given bill remaining within a 10km radius over time. That gave him a very good picture of human mobility, reflecting daily commuting traffic, intermediate traffic, and long-distance air travel, all of which help to model how a disease could spread.


Evolutionary trees like the one Charles Darwin scribbled to illustrate his epiphany are still used today to help biologists understand and communicate the diversity of life. Like Darwin and his contemporaries, today’s evolutionary biologists are part of an ongoing effort to figure out how Earth's many species are related. As new tools help biologists to analyze evolutionary relationships, the tree of life changes and grows ever more complex.

How will biologists today and in the future to organize all of this information? No one knows for sure - but a number of computer scientists and software designers are taking a crack at it! In collaboration with biologists designers are creating programs that will allow researchers to share and search through enormous amounts of taxonomical information. Some programs, like UC Davis's paloverde, take cues from familiar web tools like WIkipedia and Google Earth, allowing users to search the tree of life from various perspectives and distances.

Beyond making research more accessible to scientists and the public, software tools like this will help scientists around the world work together in new ways - developing new medicines to treat constantly evolving diseases, new products and processes that take into account changing ecosystems, and to understand biodiversity on a local and global scale.

The potential of these tools is as big as the imagination of the designers and engineers behind them - what kind of tool would you create to help organize the tree of life?


Charles Darwin: The great naturalist was born 200 hundred years ago.
Charles Darwin: The great naturalist was born 200 hundred years ago.Courtesy Public Domain
Today is the 200th anniversary of the birth of Charles Darwin, one of science’s most revered figures. Special events marking the occasion are planned throughout the world especially in England where he was born on this date (February 12th) in 1809. This year’s also the 150th anniversary of the publication of the famed naturalist’s most important work, On the Origin of Species by Means of Natural Selection, a book that revolutionized the science of biology, and one that - despite enormous amounts of evidence in its favor - remains controversial to this day. Born in the town of Shrewsbury, Charles Robert Darwin took after his grandfather Erasmus Darwin and from an early age showed a keen interest in the natural world, particularly geology, botany, and biology. While in college, a professor arranged for Charles to join the surveying expedition of the HMS Beagle to South America. It was during the five-year voyage that Darwin formulated his brilliant theory of evolution through natural selection. He returned to England in 1836 never to venture abroad again, and spent the next two decades writing out his ideas. On the Origin of Species was published on November 24, 1859, and sold out immediately. Five more editions were published during Darwin’s lifetime. He died April 19, 1882.

Darwin Online
Darwin Day site
Darwin Bicentennial at London’s Natural History Museum
About Darwin
Voyage of the Beagle (eBook)
Galapagos Islands in peril


Year of Science Logo
Year of Science LogoCourtesy COPUS
The Coalition on the Public Understanding of Science (COPUS) kicked off Year of Science 2009 (YoS2009) -- a national, yearlong, grassroots celebration--this week in Boston at the annual meeting of the Society for Integrative and Comparative Biology. COPUS, which represents more than 500 organizations, is celebrating how science works, who scientists are, and why science matters.

YoS2009 participants—museums, federal agencies, K–12 schools, universities, scientific societies, and nonprofit and for-profit organizations from all 50 states and 13 countries—will host events in celebration of YoS2009. Regionally connected YoS2009 participants are bringing science to their local communities in innovative ways. To learn about YoS2009 events near you click here.

A special web site will help the general public learn more about this yearlong, national event. Highlights from the dynamic YoS2009 Web site include the integration of components from the newly launched Understanding Science web site, Flat Stanley explorations of science, the opportunity to name a new species of jellyfish or adopt a species for the Encyclopedia of Life, and a contest to build the most scientific pizza.

All of these events and activities foster innovative new partnerships that will bring science and the public closer together locally, regionally, and nationally—all in a growing celebration of science!


Greetings from lunar orbit, Dec 24, 1968

Forty years ago the crew of Apollo 8 delivered a live, televised Christmas Eve broadcast after becoming the first humans to orbit another space body.

"The vast loneliness is awe-inspiring, and it makes you realize just what you have back there on Earth," Lovell said. Wired

First public radio broadcast, Dec. 24, 1906

Speaking of famous Christmas eve broadcasts, it's worth remembering that Reginald Fessenden made what is generally recognized as the first public voice-over-radio broadcast on Dec. 24, 1906.


Catholic Pope salutes 400 year anniversary of Galileo and his telescope

Galileo telescope replica
Galileo telescope replicaCourtesy Michael Dunn
Pope Benedict XVI chose today's winter solstice to remark that the 400th anniversary of Galileo's use of a telescope is soon upon us. Galileo was condemned by the Catholic Church for supporting Nicholas Copernicus' discovery that the Earth revolved around the sun. In 1992, Pope John Paul II apologized, saying that the denunciation was a tragic error.

Benedict said understanding the laws of nature can stimulate understanding and appreciation of the Lord's works. Newsvine

International Year of Astronomy (IYA2009)

2009 has been designated International Year of Astronomy (IYA2009) by the International Astronomical Union (IAU) and the United Nations Educational, Scientific and Cultural Organization (UNESCO). I recommend checking out the International Year of Astronomy website for news and events.

The vision of IYA2009

The vision of IYA2009 is to help people rediscover their place in the Universe through the sky, and thereby engage a personal sense of wonder and discovery.

Learn more about IYA2009


Iraqi National Museum
Iraqi National MuseumCourtesy US Department of State
The former director general of the Iraqi National Museum, Dr. Donny George Youkhanna, will give two presentations in the Twin Cities this November.

The first presentation, “Mesopotamia: The Beginning of Civilization,” will focus on the archaeology and cultural history of Iraq. It will take place on Wednesday, November 12 from 11:30 a.m.-12:30 p.m. in Sundin Music Hall, on Hamline University’s Saint Paul campus.

The second presentation, “Looting of the Iraq Museum: The Loss of a Nation’s Memory,” will focus on the status of the Iraqi museum, the restitution of antiquities from other countries, and the ongoing looting of Iraq’s archaeological sites. A panel discussion will follow. It will also take place on November 12. It will be held from 6:00-8:30 p.m. at the Weisman Art Museum on the University of Minnesota’s Minneapolis campus.

Both events are free and open to the public. More information about the events can be found here.