Smithsonian.com

An artist's impression of HLX-1 (credit: Heidi Sagerud)

Until now, there have been two known types of black holes: stellar-mass black holes that are several times more massive than our sun and are created when really big stars die out, and supermassive black holes that are millions to billions of times the mass of the sun and which sit in the center of most, maybe all, galaxies, including our own Milky Way. While astrophysicists have been fairly certain of how the smaller black holes are created, the creation of the larger ones has been largely a mystery. The main hypothesis is that they are formed from the merger of multiple medium-size black holes. But no one had ever confirmed the existence of black holes of this size. Until this week.

A team led by scientists at the Centre d’Etude Spatiale des Rayonnements in France reports in today’s issue of Nature that they have found a black hole that is more than 500 times more massive than the sun. They found an X-ray source, now named Hyper-Luminous X-ray source 1 (HLX-1), on the edge of the galaxy ESO 243-49 that has a maximum X-ray brightness about 260 million times that of the sun. As gas falls into a black hole, energy is released, much of it in the form of X-rays. Only a medium-size black hole could create an X-ray signature that bright, the scientists say.

“This is the best detection to date of such long sought after intermediate mass black holes,” lead author Sean Farrell said in a statement. “Such a detection is essential. While it is already known that stellar-mass black holes are the remnants of massive stars, the formation mechanisms of supermassive black holes are still unknown. The identification of HLX-1 is therefore an important step towards a better understanding of the formation of the supermassive black holes that exist at the center of the Milky Way and other galaxies.”

Serengeti lions (courtesy of flickr user Andries3)

Unlike every other species of cat, lions are social animals that live in groups. They gather in prides that consist of 1 to 21 females and their offspring and 1 to 9 males. But why they do so has been a mystery. One popular hypothesis has been that the female lions come together to hunt cooperatively. However, a new study, published in the journal Animal Behaviour, says that prides form to protect their territory, and themselves, from other lion groups.

Anna Mosser and Craig Packer, ecologists at the University of Minnesota, St. Paul, analyzed 38 years’ worth of behavioral data from 46 lion prides in Tanzania’s Serengeti National Park. They looked at territory size and quality, pride composition, fitness of individuals, reproductive success and how these factors changed in relation to neighboring prides.

Larger prides gained access to better territory, often the regions closest to river confluences where there was good hunting. And they were also better able to hold on to disputed territories and gain new territory of better quality. Females within these larger groups produced more cubs and were less likely to be hurt or killed.

“The most important way to think about this is that lion prides are like street gangs,” Packer told BBC News. “They compete for turf. The bigger the gang, the more successful it is at controlling the best areas.”

In addition, the ecologists were surprised to discover that males sometimes killed females of neighboring prides. In doing so, males may be able to reduce their neighbors’ numbers and alter the power balance between the prides.

The ISS and docked Discovery pass over the Sage Gateshead in Newcastle Upon Tyne, England. (15-second exposure, courtesy of flickr user Bichologo)

Though I may be tweeting (@SarahZielinski), I’m still not exactly convinced of the value of Twitter. That said, a new service called Twisst (follow @twisst) is starting to convince me otherwise. Twisst uses Twitter in an interesting mashup with other services to let followers know when they can view the International Space Station (ISS) as it passes overhead. Here’s how it works:

1. First, Twisst asks Twitter.com which twitter users are following the @twisst account and what location these people have entered in their Twitter profile.

2. Next, these locations are ‘geocoded’. This means Twisst tries to find out what the geographic coordinates are for each location. Google Maps is used for this, or, when Google can’t figure out the right coordinates, Yahoo.

3. When coordinates are found for the Twitter user, Twisst goes to the website www.heavens-above.com to see when ISS will fly over at those coordinates.

4. To find out what the local time is for the @twisst follower, Twisst asks the geographic database Geonames in which time zone the location is.

5. So, every time the International Space Station is coming, Twisst sends the follower an alert through Twitter. It announces when ISS will pass, at the users local time. Also Twisst tells whether it is a remarkable nice one or not - so how bright and how high the space station will be on that pass.

The Twisst Web site includes hints for how to spot the ISS and information about the ISS and other objects in the sky. Twisst is just getting started, so I can’t yet evaluate whether or not it works. But even though they’re using publicly available data that you could look up yourself, it should be nice to have someone else pick out the useful bits (the Heavens Above Web site is not particularly user-friendly). And what I find particularly interesting is that this idea didn’t come from a bunch of web programmers or even astronomers; this great idea came from a couple of freelance writers in the Netherlands.

Cake may normally fall under the purview of Food and Think, but I couldn’t let them have these videos. Last week, The Periodic Table of Videos (I’ve shared their ytterbium and hydrogen videos in the past) celebrated one year on YouTube by baking a cake in the lab (first video) and then trying one of their favorite methods (blowing up liquid oxygen) to destroy it (second video). They couldn’t eat the cake, of course, because it had been created in the lab. While once it may have been acceptable for chemists to create party drinks in the chemical vats, for example, they can’t get away with stuff like that today for safety reasons. But blowing things up is a good alternative, I’d say.

Image Science and Analysis Laboratory, NASA-Johnson Space Center.

On June 12, as the International Space Station passed over the Kuril Islands northeast of Japan, an astronaut looked out the window and saw Sarychev Peak, on Matua Island, in the early stage of an eruption, and he took some photos with a digital camera.

This detailed astronaut photograph is exciting to volcanologists because it captures several phenomena that occur during the earliest stages of an explosive volcanic eruption. The main column is one of a series of plumes that rose above Matua Island on June 12. The plume appears to be a combination of brown ash and white steam. The vigorously rising plume gives the steam a bubble-like appearance. The eruption cleared a circle in the cloud deck. The clearing may result from the shockwave from the eruption or from sinking air around the eruption plume: as the plume rises, air flows down around the sides like water flowing off the back of a surfacing dolphin. As air sinks, it tends to warm and expand; clouds in the air evaporate.

In contrast, the smooth white cloud on top may be water condensation that resulted from rapid rising and cooling of the air mass above the ash column. This cloud, which meteorologists call a pileus cloud, is probably a transient feature: the eruption plume is starting to punch through. The structure also indicates that little to no shearing wind was present at the time to disrupt the plume….

By contrast, a cloud of denser, gray ash—probably a pyroclastic flow—appears to be hugging the ground, descending from the volcano summit. The rising eruption plume casts a shadow to the northwest of the island (image top). Brown ash at a lower altitude of the atmosphere spreads out above the ground at image lower left. Low-level stratus clouds approach Matua Island from the east, wrapping around the lower slopes of the volcano. Only about 1.5 kilometers of the coastline of Matua Island (image lower center) are visible beneath the clouds and ash.

NASA also has a 3-D version of the Sarychev Volcano eruption online (you’ll need a pair of red-blue 3-D glasses), and you can view more astronaut photos at NASA’s Gateway to Astronaut Photography.

Find the entire collection of Pictures of the Week on Surprising Science’s Facebook fan page.

Statisticians and political scientists have been having a field day with the results from the Iranian elections earlier this month. Was the election rigged? We may never know, but there is enough buried in the math to make us think that it might have been so. Even then, though, there is also enough to make us believe that everything is legit. Here are a few analyses that I found particularly interesting:

Busy calculators after Iran’s election (courtesy of flickr user Sunshine Rabbit)

Clean Data

Immediately after the election, doubts were raised over the legitimacy of the data because each time a new batch of voting results were released (they come out in pieces in Iran, similar to the United States), the percentage of votes going to President Mahmoud Ahmadinejad was the same: 67 percent. Data usually isn’t clean, and some started to wonder whether the results had been fabricated.

An analysis by University of Wisconsin math professor Jordan Ellenberg in Slate, however, delves deeper into the data to show that it was actually messier than might be expected. The results didn’t come out city by city but in large batches that combined data from several areas, which meant that Ahmadinejad’s vote totals were really averages. And the Law of Large Numbers dictates, as Ellenberg wrote:

Averages of widely varying quantities can, and usually do, yield results that look almost perfectly uniform. Given enough data, the outliers tend to cancel one another out.

Ellenberg concludes that the data is “definitely messy enough to be true.”

Benford’s Law

Several analyses have looked at the first digits of the Iran election results to see if they comply with Benford’s Law, which is:

In lists of numbers from many (but not all) real-life sources of data, the leading digit is distributed in a specific, non-uniform way. According to this law, the first digit is 1 almost one third of the time, and larger digits occur as the leading digit with lower and lower frequency, to the point where 9 as a first digit occurs less than one time in twenty. This distribution of first digits arises logically whenever a set of values is distributed logarithmically.

One analysis using this tack, by Boudewijn Roukema of the Nicolaus Copernicus University in Poland, concluded that there were nearly twice as many vote counts beginning with the digit 7 for Mehdi Karroubi than would be expected with Benford’s Law. In addition, Roukema suspected that the results for Ahmadinejad, in which there were fewer 1s and more 2s and 3s than expected, would have been likely if someone chose to manipulate the results by changing the 1s at the beginning of the vote totals to 2s and 3s. It would also have led to an overestimate of Ahmadinejad’s totals by several million votes.

Walter Mebane, a political scientist and statistician at the University of Michigan, also used Benford’s Law in his analysis, in which he also finds several irregularities in the Iran election results. But even he admits that though his results are “compatible with widespread fraud,” they are also “compatible with Ahmadinejad having actually won.”

The Last Two Digits

Two graduate students in political science at Columbia University took yet a third take at the data. In an analysis that they summarized in a Washington Post op-ed, they examined the last two digits of the vote counts from 29 provinces for each of the four candidates (e.g., if someone received 14,579 votes, only the 7 and 9 were considered in the analysis).

The last two digits in election results are random noise, and the distribution of digits should be fairly even—each digit should appear around 10 percent of the time. Humans, though, are poor random number generators and when we make up numbers, we tend to choose some numbers more frequently than others. In the Iran results, only 4 percent of the numbers end in the digit 5 while the digit 7 appears 17 percent of the time. Results that deviate this much would be expected in about four of every 100 elections.

Humans also have problems creating numbers that have non-adjacent digits (i.e., you are less likely to come up with 72 than with 23), but these numbers should also follow random patterns and about 70 percent of the pairs should consist of non-adjacent digits. However, in the Iran results, just 62 percent do so. Again, these results would be expected in about 4 of every 100 elections. But the combination of the two results would be expected in only 1 of every 200 elections. Improbable, perhaps, but not impossible.

Where does that leave us? We may never know if the reported results are real or not. My personal favorite bit of data from all of this, though, requires no calculations to lead to questions of election legitimacy. This quotation, from Abbas-Ali Kadkhodaei, a spokesman for Iran’s Guardian Council, would make almost anyone think twice:

Statistics provided by Mohsen Resaei in which he claims more than 100% of those eligible have cast their ballot in 170 cities are not accurate—the incident has happened in only 50 cities.

(For more on the Iran election result analyses, check out Nate Silver on fivethirtyeight.com)

Zeynel Bey Mausoleum, Hasankeyf (courtesy of flickr user birasuegi)

I don’t know how archaeologists keep from going stark staring mad. Not from the long, hot hours digging in the dirt, or the difficulty of using pot sherds, post holes and bits of bone to recreate an ancient culture. What’s got to be the most frustrating thing about being an archaeologist is watching precious traces of history be lost to the elements, poachers or (ahem) progress.

But there’s good news this week for archaeology fans: the dam that would submerge the 10,000-year-old city of Hasankeyf in Turkey just lost its funding. The Environmental News Service has the story, which was picked up by Brendan Borrell (who has written about chili peppers and big scary cassowaries for us) at Scientific American.

Hasankeyf, on the banks of the Tigris River, was home to a Roman fortress, a Byzantine bishopric, the Turkish Artukids, the Kurdish Ayyubids, the Mongols, the Ottoman Empire and now modern Turkey. The government proposed moving some of the city’s monuments to higher ground, as the Egyptians did with Abu Simbel and other temples when the Aswan Dam was built. But protests from archaeologists and environmentalists (the proposed Ilisu Dam would disrupt downstream ecosystems) seem to have swayed public opinion against the dam. Its main funders, Germany, Austria and Switzerland, are apparently backing out of the project.

Smithsonian magazine’s story about Hasankeyf was part of a package about 15 must-see endangered cultural sites. We’ll keep you updated about the status of the others—and please let us know if you hear anything about them. There are so many things for an archaeology fan to worry about: a Peruvian adobe city that is in danger of being dissolved by rain, Inuit relics lost to sea level rise, a fort in India shaken by earthquakes and an Irish archaeological site that could be intersected by a new toll road. But it’s great to know that Hasankeyf is high and dry for now.

Would you take this pill? (courtesy of flickr use steveb_ohio)

In the United States, there are “drugs” and there are “dietary supplements.” Each are chemicals intended to improve your health, but they are held to very different standards of regulation: Before drugs can be sold, a company must prove to the Food and Drug Administration that their product is safe and effective. Dietary supplements, meanwhile, do not need approval from the FDA before they are marketed; companies do not need to prove that these substances are safe or effective before they are sold. If a supplement proves harmful, though, the FDA can ban the substance, like it did with ephedra in 2006.

The Zicam warning issued last week by the FDA reveals a little-known third class of chemicals marketed for your health—homeopathic drugs. These are technically drugs, but they do not have to go through the long approval process; they receive automatic approval from the FDA as long as the Homeopathic Pharmacopoeia Convention of the United States adds the substance to their list. No long trials, no science needed.

On its face, this shouldn’t be too much of a problem, because homeopathic drugs shouldn’t have any active ingredients in them. Yes, you read that correctly. See, homeopathy is a type of alternative medicine in which a compound is put through a series of dilutions until little, if any, of the compound remains. It has been proposed that homeopathic drugs work by “water memory,” which is a load of bunk. But at least if the “drug” doesn’t have any pharmacologically active substances left in it, then it shouldn’t have any side effects, either. The biggest risk by taking them should be that of not having taken something that would actually work.

But Zicam, which fell under the homeopathic drug label, wasn’t diluted to the point where it was indistinguishable from water. It contains biologically active levels of zinc. And it’s that zinc that is suspected to be behind reports of a decrease or loss of smell in Zicam users. The FDA has now asked Zicam’s maker to “submit a new drug application to demonstrate safety and efficacy.”

Herbal supplements and homeopathic drugs are just a couple of examples of the perils and popularity of alternative medicine. People who do not smoke, do eat organic food and drink only bottled water have no problem consuming substances that are completely unregulated, even in place of pharmaceuticals with strong trial evidence to back up their claims. Where is the sense in trying out random chemicals from unknown sources just because someone told you that it might make you feel better or lose weight or sleep more soundly?

We all want the magic cure, but it isn’t going to come from a homeopath or the herbal supplement industry or any other of the purveyors of woo. But what’s really sad is to see people, children sometimes, that modern medicine could help but who are sidetracked by this quackery.

(Hat tip: Science-Based Medicine)