The Sky is Waiting.
One of the Gravity Probe B Spheroids…(Credit: NASA/Don Harley)
A mission decades in the making has come to fruition. Recently, scientists have announced the results of the Gravity Probe B experiment. This mission was conceived way back in 1963 and had to await the birth of entirely new technologies before even reaching orbit. [Read more...]
Amid the sexier transiting exoplanet discoveries released earlier this week by the NASA Kepler team came an exoplanet discovered by a lesser known technique; that of gravitational lensing. MOA, or Microlensing Observations for Astrophysics, is a joint Japan/New Zealand venture looking for dark matter objects passing in front of stars and bending their light via gravitational lensing. First predicted by Einstein and famously observed during the total solar eclipse of 1919, several gravitational lenses are now known and documented in nature, from stellar type objects to massive galaxy clusters.
A great scientific revolution may be upon us. This week we look at Massive: The Hunt or the God Particle by Ian Sample. Out from Virgin Books, Massive can be said to be a book over 13 billion years in the making. At the heart of the search lies a simple particle: the Higgs-boson, a hypothetical particle that imparts mass on the universe.
There’s a wonderful anecdote told by Stephen Hawking about the completion of A Brief History of Time. His publisher admonished him not to include any mathematical equations, stating that each subsequent equation would cut the sales of the book by half.
(The author compromised at two). And so it goes; would-be science and math popularizers must often contend with publishers who tell them not to ‘scare away’ the public, while science writers think to themselves, “but this is just so cool,” and in the words quoted by this week’s author taken from Buffy the Vampire Slayer, “This could be mathier…”
Which leads us into this week’s fascinating review of The Calculus Diaries: How Math can help you Lose Weight, Win in Vegas, and Survive a Zombie Apocalypse by Jennifer Ouellette. Founder of the blog Cocktail Party Physics, Mrs. Ouellette is no stranger to writing on all things math and physics related, having authored The Physics of the Buffyverse and Black Bodies and Quantum Cats. In the Calculus Diaries, she tackles a subject that perhaps sends many of us screaming into the void during our high school college prep years, as she demonstrates how calculus is woven into our everyday lives. Interspersed throughout are fascinating fortrays into the history of mathematics, definitely tales worth telling. Stop and think; how many famous mathematicians can you name? Probably one of our favorite tales is Nick the Greek’s presentation of Albert Einstein to his Vegas cronies as, “Little Al from Princeton; controls alotta the action out in Jersey…”
But in the end, it’s all about doing the math. The Calculus Diaries doesn’t back down and demystifies much of higher mathematics for the layman; the book would serve a student well as a good segue way into a course or as a companion to Calculus for Dummies. From integrals to derivatives, it’s all here; for those who wish it “could be mathier,” a lengthy appendix of rules including the Top Ten calculus functions and the Calculus of the Living Dead is included. This book took much of the mystery out of calculus for me as I instantly recognized where algebra meets calculus and found a common basis to jump off from.
The author also gives us a good insight into how a lack of math literacy may consistently beat us in our everyday lives. And we’re not just talking about a zombie plague here. From taking on a mortgage to losing weight to beating the odds in Vegas, a failure to understand the math behind the game of life can lead to the house winning, every time. The example of a game of craps was very insightful; the odds are stacked just ever so slightly in the favor (less than 2%) of the house, but that’s just enough to, well, build a city like Las Vegas in the middle of a barren desert. The author even successfully demonstrates that stacking the odds in favor of the players may not lead to short term success as a gambler. Time and time again, we humans simply ‘suck’ (a technical term) at calculating risk and gain. Economic parallels are drawn between the great 17th century tulip mania in Holland and the current real estate market meltdown of today. The author adeptly illustrates the calculus of bubble markets and interest rates. Occasionally, as was the case during the recent crash, someone would raise a math-based objection, but everyone was too busy making a killing to notice… they all scattered, however, at the first sign of a buyer not showing up with the loot!
The current weight craze (you pick the latest one!) is also a good illustration of how our lack of math literacy does us in. Our bodies are good accountants; while we may cry foul and blame metabolism, carbs, glutens, etc. it really is a matter of calories in, calories out. Ideas to beat the Harris-Benedict equation have included everything from fat massagers to “martini diets”, but the reality is it’s hard to top “the eat less and exercise more” mantra.
And don’t forget the zombies. The Calculus Diaries examines the history of biological outbreaks and shows how the exponential growth or decay of infected populations takes off. Should I stay barricaded in this mall and duke it out with said zombies, or flee to safer ground? The Calculus Diaries will help you make the call as you’re counting up provisions and ammunition.
The release of The Calculus Dairies from Penguin Press this August 31st couldn’t be timelier. As the school year begins and another batch of students begins to feel the dread of math phobia seeping in, this book offers an empowering hope. Read The Calculus Diaries or gift it to that benighted student; it may just inspire a personal mimetic “this is that…” moment!
NASA has located an old friend on the lunar surface; Lunokhod 1, which landed on the lunar surface in 1970 and fell silent after 11 months of service. A Soviet unmanned rover, Lunokhod 1 delivered some first rate science. Remember, the Apollo astronauts stayed on the lunar surface for a period of time equivalent to a weekend camping trip. With its old school tech, Lunokhod 1 is decidedly steam punk in appearance. Fans of this space will also remember its sister rover Lunokhod 2, purchased by Richard Gariott for $68,500 in 1993. Both were imaged and recovered by the Lunar Reconnaissance Orbiter recently, and now scientists are recruiting the rovers to conduct science once again. Lunokhod 1 was equipped with corner cube prisms, which reflect laser light back at exactly the direction that it came from. On April 22nd of this year, scientists at the Apache Point observatory in New Mexico fired (you always “fire” lasers!) laser pulses of light via the 3.5 meter telescope and were surprised with the results; more than 2,000 photons were successfully gathered on the first try. In fact, the reflectors on Lunokhod 1 are now brighter than on Lunokhod 2, which may be a scientific mystery in and of itself. Scientists hope to use studies in how the Moon moves through space to search out any potential kinks in General Relativity. That’s right; in the true spirit of science, Relativity (and Gravity, for that matter) is still being run through the mill, over a century later. Thus far, reality, as always, looks to be firmly on the side of Einstein, with the help of a now stationary defunct Soviet-era rover!
We just can’t seem to get enough of NASA’s Fermi Gamma-Ray Space Telescope. The successor to the late Compton observatory that was de-orbited in 2002, Fermi has already pinpointed over 1,000 discrete gamma-ray sources, five times more than previously known. Now Fermi has also provided a rare test of Einstein’s theories of relativity. Relativity says that all electromagnetic waves (including highly energetic gamma-rays) travel through space at the same cosmic speed of 186,282 miles per second. Being a classical theory, however, what Einstein doesn’t do is meld gravity satisfactorily with the other three fundamental forces; electromagnetism and the strong and weak nuclear forces. Gravity stubbornly refuses to be unified, and such a goal has been the holy grail of physics for over the last half century. An alternative model of gravity at the microscopic scale would say that the nature of space-time is “frothy,” and a predicted effect should be a measureable drag induced on high energy photons. Recently, Fermi had a chance to put this to the test; on May 10th of last year, GRB 090510, a short gamma-ray burst 7.3 billion light years distant, was measured by Fermi’s Large Area Telescope. The verdict; gamma-ray photons varying a by a factor of a million times in energy arrived just nine-tenths of a second apart, far below what would be predicted by “frothy” space… that’s round one for Einstein!
Researchers are calling in the big guns in the quest to understanding black holes. Specifically, scientists at the Rochester Institute of Technology are using time on some of the fastest and most powerful computers in use to model and predict the activity of super massive black holes. But these aren’t your ordinary off the shelf PCs; their laboratory New Horizons machine is a computer cluster of 85 nodes with 4 processors that is capable of passing data at a rate of 10 gigabytes per second. Try that on your family Mac book! Further grants totaling $2.9 million will enable the team to hone their theoretical models over the next 3 years on ever faster machines. “It’s a thrilling time to study black holes, ” states center director Manuela Campanelli. If predictions match observations, these models may also serve as the best proof yet of Einstein’s General Theory of Relativity…more to come!
For years, a unique binary system has plagued Einsteinian physics. DI Herculis (DI Her) is a seemingly innocuous binary star about 2,000 light years distant. Type B stars each about five times the mass of our Sun, these stars are in a mutual orbital embrace about 0.2 A.U. apart. Visually, the system is at magnitude +8.5, and the orbit is inclined along our line of sight so that mutual eclipses occur every 10.55 days. First recorded in 1900, this feature allows the systems’ mass, luminosity and orbital characteristics to be known to a high degree of precession. For the past several decades, however, astronomer Ed Guinan at Villanova University couldn’t shake an odd effect; namely, periastron of the two stars is advancing at a rate of only ¼ what’s predicted by Einstein’s theory of general relativity. Is an unseen companion lurking in the DI Her system, or is it Albert himself who was wrong? Prediction of such anomalies as the precession of the perihelion of Mercury is one of the great cornerstones of relativity. In a massive system such as DI Her, this effect should be even more pronounced. Like the Pioneer anomaly, several would-be theorists have pointed to this discrepancy as a potential chink in the relativistic armor…
Enter Simon Albrecht of MIT. Using a 1.93-meter telescope to obtain a high-resolution spectrograph of the two suns, a bizarre fact has become apparent; both stars are tipped on their rotational axes, giving them an orbital “kick” at their closest approach. This configuration adequately accounts for the relativistic anomaly. Apparently, DI Her underwent a close passage of another star or massive object sometime in its history. Guinan is relieved, but will no doubt continue to receive a flood of email from alternate-gravity theorists!
The next time you’re studying the Lorentz equation or are forced to account for Relativity on your Buzzard Ramjet trip to Sirius, thank Einstein that we’re here at all! Scientists Jacques Laskar and Mickael Gastineau at the Paris Observatory have been modeling orbital dynamics in our solar system and have come up with some “disturbing” results. It has long been known that Jupiter has a shepherding effect on the inner solar system, smoothing out planetary orbits while ejecting or sweeping up incoming debris. However, if you model the planetary orbits taking into account only classic Newtonian motion, the odds that Mercury goes out of whack in the Sun’s 10 billion year odd life span are about 60%. Throw in Einstein, and the effect shrinks to less than 1%. A careening Mercury would be a bad thing; if it impacted Venus, we would get showered with debris over a million year span, and if it hit us, well, it would just be a bad day. The best thing it could do is harmlessly impact the Sun. Even a near miss with the Earth could drastically alter our orbit, not to mention tinker with our stabilizing Moon. Fortunately, the tiny tweak that the Sun’s gravitational well gives Mercury’s eccentric orbit via General Relativity assures that a resonance keyhole with Jupiter’s orbit probably won’t happen. Keep in mind, we’re talking tiny effects that pile up over billions of years… every time an asteroid whizzes by, we launch a Space Shuttle, or LeBron performs a slam dunk, the Earth gets a tiny push. Over billions of years, tiny forces do add up (ever heard of the Butterfly Effect?) This is why astronomers cannot predict the positions of planets more than a million or so years into the future. Incidentally, the precession of Mercury’s orbit still stands as one of the great observational proofs of Relativity. One also wonders if such a perturbation might have been the fate of Theia, the Mars sized impactor that has been hypothesized to have struck a prehistoric Earth and created our Moon. So the next time you see gravity bend light at relativistic speeds, thank Einstein for protecting our home planet Earth!
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Pictured is a Delta IV rocket launch from Cape Canaveral on November 21st, 2010. The image is a 20 second exposure taken at dusk, shot from about 100 miles west of the launch site. The launch placed a classified payload in orbit for the United States Air Force.
Difficult but not impossible to catch against the dawn or dusk sky, spotting an extreme crescent moon can be a challenge. The slender crescent pictured was shot 30 minutes before sunrise when the Moon was less than 20 hours away from New. A true feat of visual athletics to catch, a good pair of binoculars or a well aimed wide field telescopic view can help with the hunt.
The Sun is our nearest star, and goes through an 11-year cycle of activity. This image was taken via a properly filtered telescope, and shows the Sun as it appeared during its last maximum peak in 2003. This was during solar cycle #23, a period during which the Sun hurled several large flares Earthward. The next solar cycle is due to peak around 2013-14.
Located in the belt of the constellation Orion, Messier 42, also known as the Orion Nebula is one of the finest deep sky objects in the northern hemisphere sky. Just visible as a faint smudge to the naked eye on a clear dark night, the Orion Nebula is a sure star party favorite, as it shows tendrils of gas contrasted with bright stars. M42 is a large stellar nursery, a star forming region about 1,000 light years distant.
Orbiting the planet in Low Earth Orbit (LEO) every 90 minutes, many people fail to realize that you can see the International Space Station (ISS) from most of the planet on a near-weekly basis. In fact, the ISS has been known to make up to four visible passes over the same location in one night. The image pictured is from the Fourth of July, 2011 and is a 20 second exposure of a bright ISS pass.
Next to the Sun, the two brightest objects in the sky are the Moon and the planet Venus. In fact, when Venus is favorably placed next to the Moon, it might just be possible to spot the two in the daytime. Another intriguing effect known as earthshine or ashen light is also seen in the image on the night side of the Moon; this is caused by sunlight reflected back off of the Earth towards our only satellite.
A mosaic of three images taken during the total lunar eclipse of December 21st, 2010. The eclipse occurred the same day as the winter solstice. The curve and size of the Earth’s shadow is apparent in the image.
Review: Himmler’s War by Robert Conroy
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Historical “What If’s?” often make for great fiction.
What if the South had won Gettysburg? Or if the U.S. had never entered World War I? Or Roosevelt never built the bomb at Einstein’s urging? These are just some alternate histories that are intriguing to consider. Or are we in fact living in an alternate timeline now? [Read more...]