Category Archives: Science

What do birds do in an eclipse?

The August solar eclipse had a noticeable impact on solar power generation and other human activities (such as tourism).

Birds are quite aware of the sun and weather conditions. Many birds are active at particular times of day, hunting in sunlight or in darkness. So what do birds make of a sudden, unexpected nightfall and then another dawn

Benjamin Van Doren, Andrew Farnsworth, and Ian Davies write in BirdCast about “What Do Birds Do During a Total Eclipse?” The article is a collection of field observations during the solar eclipse.

Overall, birds seem to have responded to the darkness the same way that they behave at night. Daytime species seem to have gone to roost, and nighttime species came out to hunt. The eclipse doesn’t last very long, though, so nobody had time to completely go to sleep or wake up.

One interesting image shows radar data that detects birds in the air. As the total eclipse passed the area, the air cleared in the shadow. Daytime birds dropped down toward their roosts, and nighttime birds did not take off yet. The result is a circular trace of “empty sky”. Cool!

The reports also note that insects woke up, and flowers started to close.  Many of the reports indicate that the birds seemed confused, which is certainly reasonable under the circumstances.

BirdCast also reminds us that It will take a long time for the Southern coast of the US to recover from the Hurricanes of September 2017. We will no doubt learn that wildlife was affected by the huge storms. For instance, it is likely that birds (and other animals) were pushed North by the powerful winds. As they find there way back to the usual homes, like the people the birds will find trees (their homes) destroyed, and flood waters everywhere. As everyone returns and rebuilds, birders will no doubt report how birds cope with the storms.

  1. Benjamin Van Doren, Andrew Farnsworth, and Ian Davies, What Do Birds Do During a Total Eclipse? Observations from eBird and Radar on August 21, , in BirdCast. 2017.


Cassini End of Mission

After twenty years in space (launched 10 years Bi, Before iPhone), traveling over a billion KM, and returning data for 13 years from more than a light-hour from Earth, the Cassini Spacecraft ended its mission this week.

The project has accomplished lots of amazing science, represented by 3,948 papers so far. There will surely be a few more—lets go for 5K papers!

The end was a planned dive into the atmosphere of Saturn, collecting a few more bits of data on the way down, and assuring the complete destruction of the spacecraft.

As has been explained before, the spacecraft needed to be vaporized to prevent even the slighted chance that it might contaminate the area with Earth microbes. Aside from not wanting to harm any life that might exist on the moons or dust, we also don’t want to accidentally leave something that a later spacecraft might find and not realize was inadvertently sent from Earth.

(Which, if you think about it is way, way cool. How many human endeavors have to worry about the possibility of contaminating alien ecosystems, even in principle?)

Hence, the final dive.

This montage of images, made from data obtained by Cassini’s visual and infrared mapping spectrometer, shows the location on Saturn where the NASA spacecraft entered Saturn’s atmosphere on Sept. 15, 2017. Credit NASA/JPL-Caltech/Space Science Institute

Cassini signed off permanently on September 15. Loss of Signal. End of Mission. Lots of accomplishments.


Space Saturday

Citizen Science: NoiseCapture App

Contemporary digital technology offers many opportunities for collecting scientific data. Millions of people are carrying highly capable networked computers (mobile phones), with cameras, microphones, and motion sensors. Most personal devices have capabilities available only in a few laboratories twenty years ago.

Furthermore, these devices are in the hands of “civilians”. It is now possible to do “citizen science” for real, using personal devices to collect data and aggregate it through network services.

This has been used for environmental sensing (microbe populationsmicrobe assays, weather, air pollution, particulates,, odors), earthquake detection, food quality, detecting poachers, and wildlife observations (pollinators.  bird watching, bird song, insect song).

As I have remarked before, simply collecting data is not actually that useful scientifically. It also invites misguided pseudoscicence, if data is not carefully analyzed or misinterpreted.

What is needed is the rest of the picture, including data cleaning, careful models and analysis, and useful , valid visualization and reports.  You know, the “science” part.

This summer, a team from several French research institutions are releasing the NoiseCapture app , which allows anyone tomeasure and share the noise environnement [sic]”.

Specifically, this app measures noise in a city, as the user moves through ordinary activities. The microphone records the sounds, and GPS tracks the local of the device. (There are plenty of tricky details, see their papers [1, 2].)

The collected data is transmitted to the project’s server, where it is analyzed and cross-calibrated with other data. Any given measurement isn’t terribly meaningful, but may data points from many phones combine to create a valid estimate of a noise event. They incorporate these data into a spatial model of the city, which creates an estimate of noise exposure throughout the area [1].

Ii is very important to note that estimating noise exposure from a mobile phone microphone is pretty complicated (see the papers). Crowdsourcing the data collection is vital, but the actual “science” part of the “citizen science” is done by experts.

I’m pleased to see that the researchers have done some careful development to make the “citizen” part work well. The system is designed to record readings along a path as you walk. The app gives visual indications of the readings and the rated hazard level that is being observed. The data is plotted on interactive digital maps so that many such paths can be seen for each city. The project also suggests organizing a “NoiseCapture Party” in a neighborhood, to gather a lot of data at the same time.

Overall, this is a well thought out, nicely implemented system, with a lot of attention to making the data collection easy for ordinary people, and making high quality results available to the public and policy makers.

This research is primarily motivated by a desire to implement noise control policies, which are written with detailed technical standards. Much of the work has been aimed to show that this crowdsourced consumer device approach can collect data that meets these technical standards.

That said, it should be noted that technical noise standards are not the same thing as the subjective comfort or nuisance value of an environment. One person’s dance party is another person’s aural torture. A moderately loud conversation might be unnoticed on a loud Saturday night, but the same chat might be very annoying on the following quiet Sunday morning.

I also have to say that I was a little disappointed that the “environment” in question is the urban streetscape. For instance, the app is not useful for indoors noise (where we spend a lot of time).

Also, I would love to have something like this to monitor the natural soundscape in town and country. When the machines and people aren’t making so much noise, there is still plenty to hear, and I would love to be able to chart that. These voices reveal the health of the wildlife, and it would be really cool to have a phone app for that.

This is what “dawn chorus” folks are doing, but they don’t have nearly as nice data analysis (and non Brits can’t get the app).

Finally, I’ll note that simply detecting and recording noise is only a first step.  In the event that the neighborhood is plagued by serious noise pollution, you’re going to need more than a mobile phone app to do something about it. You are going to need responsive and effective local and regional government.  There isn’t an app for that.

  1. Erwan Bocher, Gwendall Petit, Nicolas Fortin, Judicaël Picaut, Gwenaël Guillaume, and Sylvain Palominos, OnoM@p : a Spatial Data Infrastructure dedicated to noise monitoring based on volunteers measurements. PeerJ Preprints, 4:e2273v2, 2016/09/28 2016.
  2. Gwenaël Guillaume, Arnaud Can, Gwendall Petit, Nicolas Fortin, Sylvain Palominos, Benoit Gauvreau, Erwan Bocher, and Judicaël Picaut, Noise mapping based on participative measurements, in Noise Mapping. 2016.


Book Review: “Weird Dinosaurs” by John Pickrell

Weird Dinosaurs by John Pickrell

You had me at “Dinosaurs”! : – )

I mean, a big part of the appeal of Dinophilia is that Dinosaurs are, and always have been mind-blowingly weird.

Pickrell’s point, of course, is that the last two decades have seen an explosion of new fossils, as well as new information from Buck Rogers technology. The weirdness we knew and loved has gotten even more weird.

Just as a for instance: when I was a lad, Triceratops was Triceratops, with three horns. One of the plates in this book is a painting of dozens of different species of Triceratops with an astonishing variety of facial horns and crests. It’s stunning.

This fine little book is a quick tour around the world, sampling the newest Dinosaur discoveries from China, South America, Australia, Antarctica—everywhere. Mostly, this is about all the new species of Dinosaurs that have been discovered, but the main point is the diversity and wonderful strangeness of the new understanding of the ancient times.

Some of the discoveries have had a splash of publicity, but almost all of the big finds are part of a stream of equally interesting, but less known new discoveries.

Pickrell gives a lot of attention to the history and lives of Paleontologists. These Dinosaurs didn’t discover themselves, and the story of how they were found and interpreted is important and cool.  He’s also a working paleontologist, so he explains the techniques and challenges of the field work that yields these wonders.

In some cases, fossils were uncovered a long time ago, and have been reinterpreted in light of later information. Other finds have been lost forever, but reconstructed from new data. Yet others have been discovered in some dusty back room. And, of course, whole new regions of the world are being scientifically explored for the first time.

Altogether, the story of Dinosaurs, and birds and mammals, too, is becoming much more complicated and nuanced. Everywhere we look there are more and different Dinosaurs, and we know that there are far more to be found.

Pickrell is a good writer, and his love of Dinosaurs comes through on every page. He seems to get to travel all over the world visiting Paleontologists, which is good work if you can get it.

The biggest problem with the book is that there are so few pictures. Honestly, telling me a list of all the species found at a given location is impossible for me to follow, especially with no illustrations to help. This is definitely a book that deserves a plate on every few pages. I know that is probably impractical, but I can wish for it.

  1. John Pickrell, Weird Dinosaurs: The Strange New Fossils Challenging Everything We Thought We Knew, New York, Columbia University Press, 2016.


Sunday Book Reviews


Interplanetary Networking

Space travel faces inevitable communication challenges. Even within the solar system, distances are light minutes to hours, which means round trip latencies that preclude easy conversation. In addition, signals decay quadradically, so there is a brutal power-to-distance relationship—and power is precious in space.

Can we do better than radio signals?

Gregory Mone reports in CACM that the answer is, lasers, man! [2]

Lasers are higher frequency and narrower beams, so they can transmit more data for the same power. This can’t eliminate the latency, but can push more data in a given time. As much as 10-100 times the data, which is worth a lot of effort to make happen.

A laser is much more directional than radio, and the receiver is a telescope. The narrow beam is a challenge, because the signal has to be aimed precisely. Given than everything is moving rapidly relative to everything else, it isn’t trivial to keep a signaling laser pointed at a very distant target.

If you were to aim a beam of radio waves back at Earth from Mars, the beam would spread out so much that the footprint would be much larger than the size of our planet. “If you did the same thing with a laser,” Biswas  [of NASA JPL] says, “the beam footprint would be about the size of California.”” ([2], p. 18)

Experiments have demonstrated space laser communication, utilizing error correcting codes (to mitigate lost signals) and advanced nanoactuators to precisely aim the laser. At very large distances, power will be at a premium, so there will be no bits to spare for error correction.

The receivers are essentially telescopes, which are a very well known technology. Receiving weaker signals from farther away means bigger telescopes. Mone says that signals from the solar system need a 10-15 meter scope.

These links will still have extremely long latencies compared to terrestrial networks. This means that our Earth bound protocols need to be redesigned for the Interplanetary Internet. (Hint: timeouts don’t work well if the round trip time for an ACK is variable and measured in hours.) This work is well underway [1].


  1. InterPlanetary Networking Special Interest Group (IPNSIG). InterPlanetary Networking Special Interest Group (IPNSIG). 2017,
  2. Gregory Mone, Broadband to Mars. Commun. ACM, 60 (9):16-17, 2017.


Remote Fun Park On The Moon?

As we approach the fiftieth anniversary of the first moon landing, it is clear that humans have pulled back from space exploration and from science in general. NASA’s budget has steadily declined, dedicated scientists politically suppressed and much of the space program has calcified into a jobs program.

What can be done?

Toys! Theme parks!

There is a lot of interest these days in sending swarms of small robots to the moon. Perhaps inspired by ubiquitous remote piloted drones, why not remote operate a moon rover?  And why can’t anybody drive one, with a game controller?

The Lunatix company is proposing to sell moon-rover-driving as a game. Earth bound computer games would be linked to the lander, and could purchase driving time. Kind of like consumer drones, except on the moon [3].

The lander might have a small science payload, but mainly it is dedicated to the commercial use. (There would be merchandise and other associated sales, as well.)

This seems relatively straightforward technically. There are some tricky bits, such as linking a consumer via the Internet to an uplink to the moon. Safely linking. Securely linking. (Hint: space communications are expensive and rare, and generally not connected to the public.)

I have no idea about the commercial case. Space projects are obscenely expensive, but getting cheaper. At something like 25 Euros per minute, it seems to me that driving time would be pretty damn expensive, at least for peasants like me. But who knows? My intuitions about business plans are often wrong.

Evan Ackerman points out that this purely commercial project raises legal questions. The moon is more or less under the jurisdiction of the United Nations, as defined by treaties among nations. There seems to be no specific framework for commercial exploitation of the moon, though there will surely need to be one soon.

Aside from the equity issues about sucking money out of the lunar commons (the moon is the common heritage of all human kind), there may be environmental and other regulatory issues.

I note that a company slogan is “Leave Your Mark on the Moon!”  The users will leave behind tracks, indelible tracks, visible from Earth.  This will surely have consequences.

How happy are we going to be when the moon is covered with tread marks? Do you want to see rude graffiti defacing the surface? How will we feel about a giant cola ad written in the dust? How will Earthly strongmen react to uncensored political messages, indelibly written on the moon?

The company proposal seems to wave its hands at the legal problems and doesn’t even list any legal issues under “Risks”. That may be optimistic.

In the end, it is quite possible that money will talk. As Ackerman puts it, despite his own misgivings, “If this is the best way to get robots to the moon, then so be it”.

While there’s a small section in the Lunatix executive summary on “Legal Framework,” there are few specifics about whether or not the United Nations would approve something like this. Lunatix seems to suggest that its use case is covered under “the common interest of all mankind in the progress of the exploration and use of outer space for peaceful purposes,” but I’m not so sure. It may be that no framework exists yet (either for or against), and my gut reaction that commercializing the moon in this way somehow cheapens it is probably just me being old and grumpy. If this is the best way to get robots to the moon, then so be it.” (From Ackerman [1])

I have my doubts about this concept. We’ll see.

But the general idea that some kind of entertainment business might be one of the earliest commercial successes for space seems to be plausible. Many important technologies started out as entertainment, or were driven by markets for entertainment [2].

For example, the Internet was designed for military and scientific applications, but the earliest commercial successes were music theft, games, and pornography, which drove markets for servers, GPUs and broadband, among other things. Today’s cord cutters are simply taking advantage of the second and third generation of these technologies. And, just as the Internet has never been comfortable with the fact that it is a great mechanism for delivering pornography, space entertainment may not turn out quite as imagined.


  1. Evan Ackerman, How Much Would You Pay to Drive a Jumping Robot on the Moon?, in IEEE Spectrum – Automation. 2017.
  2. Steven Johnson, Wonderland: How Play Made the Modern World, New York, Riverhead Books, 2016.
  3. Space Tech, Luniatix. Graz University of Technology Institute of Communication Networks and Satellite Communications, 2017.



Space Saturday

Armadillos On The March!

It’s a good thing the climate isn’t changing, because if things were getting warmer, then all those crazy animals from Florida and Texas would be moving North.

Such as Armadillos.

In recent years, these weird Paleolithic beasts have been sighted more and more frequently farther North than in past centuries. They have been found in Illinois, and this month one was sighted within blocks of my house.


Overall, the data indicates that Armadillos are definitely spreading North.

Pictured here is the range of armadillos.


Naturalists say that these guys really can’t stand really cold winter days, so they used to not live here. But the last decades have seen warmer winters, and we are now habitable territory for armadillos.

I guess this could be yet another clever hoax by those sneaky scientists. Everyone knows that Big Armadillo hates America and is waging war on coal and oil. “They” will stop at nothing, including fake Armadillo sightings. Could this be opossums dressed up in foam armor?


  1. Prairie Rivers Network, Armadillos, Illinois’ Armored Invader, in Prairie Rivers Network Home. 2017.
  2. Mark Schultz, First Armadillo Confirmed In Champaign County, in WILL Radio News. 2017: Urbana.