The first requirement is the existence of laws of physics that guarantee the kind of regularities that can underlie the existence of life. These laws as we know them are based on variational and symmetry principles; we do not know if other kinds of laws could produce complexity. If the laws are in broad terms what we presently take them to be, the following inter alia need to be right, for life of the general kind we know to exist:
The neutron-proton mass differential must be highly constrained. If the neutron mass were just a little less than it is, proton decay could have taken place so that by now no atoms would be left at all.
Electron-proton charge equality is required to prevent massive electrostatic forces overwhelming the weaker electromagnetic forces that govern chemistry.
The strong nuclear force must be strong enough that stable nuclei exist; indeed complex matter exists only if the properties of the nuclear strong force lies in a tightly constrained domain relative to the electromagnetic force.
The chemistry on which the human body depends involves intricate folding and bonding patterns that would be destroyed if the fine structure constant (which controls the nature of chemical bonding) were a little bit different.
The number D of large spatial dimensions must be just 3 for complexity to exist.
It should not be too surprising that we find ourselves in a universe whose laws of physics are conducive to the existence of semi-intelligent life. After all, we are here. What we do not know—and will probably never know: Is this the only universe that exists? This is an important question, because if there are many universes with different laws of physics, our existence in one of them may be inevitable. If, on the other hand, this is the only universe, then the fantastic claims of the theists, or at least the deists, become more plausible.
You may wonder why I call the human race semi-intelligent. Rest assured, I am not being sarcastic or sardonic. I say “semi-intelligent” to call attention to humanity’s remarkable technological and scientific achievements while also noting our incredible ineptness at eradicating war, violence, greed, and poverty from the world. What is wrong with us?
References G.F.R. Ellis, Issues in the Philosophy of Cosmology, Philosophy of Physics (Handbook of the Philosophy of Science), Ed. J. Butterfield and J. Earman (Elsevier, 2006), 1183-1285. [http://arxiv.org/abs/astro-ph/0602280]
There have been many film adaptations of Victor Hugo’s timeless novel, Les Misérables, but after watching the 1935 film starring Fredric March and Charles Laughton last night, I am in no rush to see any of the others. It is, quite simply, perfect.
This movie says more in one hour and forty-eight minutes than most other movies (especially more recent ones) say in two or three hours. A riveting tale of unjust laws, poverty, inhumanity, cruelty, compassion, love, mercy, doubt, and morality, this is one of the most moving and inspiring movies I have ever seen. And just as relevant for us to today as it was in 1935 and when Victor Hugo wrote the book, first published in 1862.
We need movies like this to remind us (and in such complex and jaded times as these we do need constant reminding) that idealism can help each of us navigate through life, and—no matter what burdens we bear—to make the world a better place. Not a single minute in this movie is wasted, so artfully is each and every scene of the movie constructed. If you tire of (and are horrified by) the seemingly endless stream of dystopian prognostications in recent years, this movie is the perfect antidote. There is an alternative to a ruined world, and that change begins with you and me right now.
All of the film adaptations of Les Misérables, including this one, have a number of departures from the original novel by Victor Hugo. Behind every great movie there is usually an even greater book, and I have been remiss in never having read Hugo’s classic. That deficiency will be rectified soon.
Did you know that it is possible to observe a meteor shower when its radiant is below your horizon? When its radiant is too far south (or north, in the southern hemisphere) to ever rise above your horizon? When its radiant is even located near the Sun?
Yes you can! By video recording the Earth-facing night side of the Moon, or during a total or partial lunar eclipse, you have the opportunity to record meteors impacting the surface of the Moon. Those of us who record occultations of stars by asteroids and trans-Neptunian objects already have the equipment necessary to accurately document such events, which typically produce brief flashes of light lasting for a few hundredths of a second.
Leonid meteor lunar impact flashes of +3m to +8m were recorded in 1999 and 2001, and Geminid meteor lunar impact flashes have been recorded that were between +5m and +9m. Meteor impact events have also been recorded during lunar eclipses, such as just after the beginning of the total lunar eclipse of January 20/21, 2019.
Besides during lunar eclipses, the best time to look for meteor impact events on the Moon is when most of the Earth-facing side of the Moon is dark and illuminated only by earthshine. This occurs during the waxing crescent and waning crescent phases.
NASA has twin 14-inch telescopes that observe the nighttime part of the Moon between the phases of New and First Quarter, and between Last Quarter and New. These telescopes have recorded 435 flashes on the Moon from 2005 to April 2018.
On Mt. Kyllini (930 m), Corinthia, Greece, the 1.2 m Kryoneri telescope of the National Observatory of Athens has been employed in a four year project called NELIOTA (Near-Earth Object Lunar Impacts and Optical Transients) to monitor the Moon for lunar flashes using a two camera system (one R-band and one near-IR) at a video rate of 30 frames per second. All candidate flashes are compared against a database of artificial satellites to exclude false positives due to sunglints of satellites passing in front of the Moon. Between February 2017 and January 2019, forty lunar impact events have been detected.
Of course, you’re more likely to capture a lunar meteor impact flash during a major meteor shower.
Peter Zimnikoval in Slovakia has written a wonderful program called MetShow that will present your local circumstances for the Moon at any date and time and for any meteor shower radiant. I’ve reproduced in the gallery below the lunar circumstances for all the major meteor showers (ZHR ≥ 10) for the remainder of 2019.
Not only does the lunar phase have to be favorable, but the meteor shower radiant must be coming from a direction that will impact a nighttime part of the Moon that we can see. If the Moon is located near the radiant of a meteor shower, then most of the meteors will impact the far side of the Moon where they will be unobservable from Earth. If the Moon is located near 180˚ from the meteor shower radiant, then the meteors will favor the near side.
This year, the best meteor showers to monitor are the Eta Aquariids around May 6, the Delta Aquariids around July 30, and the Ursids around December 23.
Most meteor showers have a broad maximum, so the exact time to observe the Moon is not as important. But if the meteor shower has a sharp peak, then one should consider the time offset between the Earth and the Moon. Peter Zimnikoval writes (personal communication, 2019):
“Bombarding of the Moon’s surface is almost the same as on the Earth. The position of the observed radiant is given as the vector sum of the heliocentric motion of the meteoroids and the Earth’s motion. For the Moon, there is only a small difference due to its orbital velocity (1 km/s). Regular meteor showers cross the Earth’s orbit at the same point every year. The angular position of this point is described as solar longitude (J2000). The Moon at 3rd quarter reaches this point about 3.6 hours before the Earth (384,399 km / 29.78 km/s = 12,908 seconds = 3.6 hours). The Moon at 1st quarter reaches this point about 3.6 hours after the Earth.”
“For most of the regular meteor showers (Perseids, Orionids, Geminids) this time shift is not very important. Their maxima are not too sharp and the duration is many hours. The time shift may be important for very narrow meteor streams, where the suspected time of maximum is only a few hours and therefore observed from only a small part of the Earth. When the structure of a shower is very sharp, then small differences in the position of the Earth and the Moon passing through this stream can make a difference. At full moon or new moon, the Moon may reach a higher density of particles than the Earth, but these phases are not suitable for observation of lunar impact flares.”
Liakos, Alexios et al.(2019). NELIOTA Lunar Impact Flash Detection and Event Validation. Proceedings of the “ESA NEO and Debris Detection Conference -Exploiting Synergies-“, held in ESA/ESOC, Darmstadt, Germany, 22-24 January 2019. arXiv:1901.11414 [astro-ph.EP].
Zimnikoval, Peter (2017). Lunar impact flashes. WGN, Journal of the International Meteor Organization, 45:5.
Humans typically can hear sound waves in the range 20 Hz to 20,000 Hz. Frequencies below 20 Hz are called infrasound and frequences above 20 kHz are called ultrasound. The speed of sound in dry air at a temperature of 20˚ C (68˚ F) and an atmospheric pressure of 1 bar (slightly less than the average air pressure at sea level) is 343 m/s. Dividing the speed of sound by the frequency (in Hz) gives us the wavelength of the sound waves: 17 m (56 ft.) at 20 Hz, and 17 mm (0.67 in.) at 20 kHz.
Meteoroids enter the Earth’s atmosphere (thus becoming meteors) at hypersonic velocities, 35 to 270 times the local speed of sound (Mach 35 to Mach 270). Only a small portion of the total energy of the incoming meteoroid is transformed into visible light: most of the energy dissipated goes into acoustic shock waves. If the meteoroid is on the order of a centimeter (0.4 inches) or larger, infrasound waves are generated that can be detected on the ground, albeit after a delay of many seconds to minutes.
Infrasound waves can travel long distances, but higher frequencies are attenuated due to spreading losses and absorption over much shorter distances. There are many natural and man-made sources of infrasound waves, so identifying an incoming meteoroid as the source of the infrasound requires that we also “see” and record the meteoroid optically (the “meteor”), through radar, or VLF radio emissions from the meteoroid’s ionization trail in the Earth’s atmosphere. Ideally, all of these methods should be used at each observing station to best characterize the size and kinetic energy of each incoming meteoroid.
Infrasound detectors are not yet an off-the-shelf commodity. Chapparal Physics (http://www.chaparralphysics.com) is one good source, but seeing as they do not list any prices you know the equipment will be expensive.
An infrasound detector is basically an extremely sensitive microphone that can detect tiny changes in air pressure. A peak sensitivity around 1 Hz is probably a good place to start for detecting meteors. Meteors large and/or energetic enough to be detected on the ground are rare, not even one a day for a given station, so automated recording will be necessary.
Finally, it is important to know that louder sounds that we cannot hear (infrasound and even ultrasound) can sometimes have adverse physical and psychological effects on humans. The cause can be as simple as a malfunctioning piece of mechanical or electrical equipment, or as nefarious as a sonic weapon. It would be advantageous to have a readily available and affordable infrasound and ultrasound detector to detect problem emissions.
For example, you might want an
Infrasound detector that maps 0.02 Hz – 20 Hz to the 20 Hz – 20 kHz audible range
Ultrasound detector that maps 20 kHz – 20 MHz to the 20 Hz – 20 kHz audible range
References Silber, Elizabeth A. (2018). Infrasound observations of bright meteors: the fundamentals. WGN, Journal of the International Meteor Organization, 46:2.
I’ll be 63 in a couple of months. My the years go fast, faster still of late.
Naturally, I’m beginning to look toward retirement when I can finally devote nearly all my time and energy to astronomy, preservation and restoration of our nighttime environment, and classical music. These three avocations have been my primary interests all of my adult life.
I’m in need of some retirement advice by someone who is not trying to sell me a financial product. I’d like to semi-retire as soon as possible, but want to wait until age 70 to collect Social Security when the monthly benefit reaches a maximum. So, I guess that means gradually cutting back work hours and supplementing the lost income with some retirement benefits.
I’m in a good position in terms of having a marketable work skill for the semi-retirement years. You’d be hard pressed to find a better SAS programmer. I’ll be at SAS Global Forum 2019 in Dallas this spring if you want to talk.
Honestly, I’ve been in a bit of a funk since I started this blog back in December 2016. First, Trump got elected, and that made me realize how bad things have gotten in this country. That someone so boorish and with zero job skills as a public servant got elected as President of the United States is both frightening and depressing. And the national nightmare continues. Then, last fall, my employer moved everyone except for management into an open office environment, which I hate. Throughout my work career, I’ve always had my own office or a cubicle and now I’m in a big open room with lots of distractions and a desk half the size of what I had just a few months ago, and no place to put my books, so I had to bring them all home. No one wants to learn SAS at my company anymore, even though I do amazing things with it every day. I’m in high demand, but they’re not hiring anybody anymore with SAS skills. That’s depressing, because it is a great language and a great company and SAS Institute most definitely continues to innovate. But open source is the name of the game where I work now.
It is easy to feel isolated living in a small town. As my friend Jeff Dilks once said when he was a physics teacher in Shenandoah, Iowa, the chances of finding anyone else in a small town (or rural area) with similar interests and abilities are vanishingly small if you have “big city” interests and a specialized education. That’s true, but where else are you going to live if you want to do observational astronomy and ride a bicycle to and from work? Quality of life issues like that, you know. But loneliness, yes, and I imagine that gets to be more of a challenge in our later years.
For something like 30 years, I’ve wanted to help develop and nurture a science-oriented and education-oriented intentional community where astronomy is a major focus. I even have a name for it: Mirador Astronomy Village. Can’t think of a better way to spend my retirement years, but it takes serious money to get something like this off the ground, and money I don’t have.
With open office and all (which is pretty much ubiquitous nowadays), I’ve soured on the idea of working for “Corporate America” any longer. I’d be much happier as a public servant, trying to make the world a better place and helping to solve the many problems for which Corporate America is not the answer, and has no answers.
The word desideratum has been a part of the English language since at least 1651, according to the Oxford English Dictionary, which provides this definition:
Something for which a desire or longing is felt; something wanting and required or desired.
This word comes from the Latin dēsīderātum “thing desired”, and its plural is desiderata.
The French astronomer Auguste Charlois (1864-1910) discovered the asteroid 344 Desiderata on 15 Nov 1892 at the Nice Observatory, in southeastern France near the border with Italy. Like most of his 99 asteroid discoveries between 1887 and 1904, it is named to honor a woman. In this case, that would be Désirée Clary (1777-1860), French woman who became Queen Desideriaof Sweden.
On 25 Feb 2019, I recorded 14.1-magnitude 344 Desiderata passing in front of the 14.6-magnitude star UCAC4 639-020401 in the constellation Auriga. Right before the event, star and asteroid formed a 13.6-magnitude blended image, and when the asteroid covered up the star, the brightness dipped 0.5 magnitude to the brightness of the asteroid alone. This great cover-up event lasted 16.8 seconds. Here’s a light curve of the event as a function of time.
That dip to the right (after) the asteroid covered up the star suggests that a smaller satellite of the asteroid might have also passed in front of the star. Alas, it is only noise. We can tell this by looking at the light curve of a nearby comparison star at the same time.
Here is the smoothed and fitted light curve of the asteroid occultation event.
Max Ehrmann (1872-1945) wrote a prose poem Desiderata (Latin: “things desired”) in 1927 that has since become well known, and for good reason.
Go placidly amid the noise and the haste, and remember what peace there may be in silence. As far as possible, without surrender, be on good terms with all persons.
Speak your truth quietly and clearly; and listen to others, even to the dull and the ignorant; they too have their story.
Avoid loud and aggressive persons; they are vexatious to the spirit. If you compare yourself with others, you may become vain or bitter, for always there will be greater and lesser persons than yourself.
Enjoy your achievements as well as your plans. Keep interested in your own career, however humble; it is a real possession in the changing fortunes of time.
Exercise caution in your business affairs, for the world is full of trickery. But let this not blind you to what virtue there is; many persons strive for high ideals, and everywhere life is full of heroism.
Be yourself. Especially do not feign affection. Neither be cynical about love; for in the face of all aridity and disenchantment, it is as perennial as the grass.
Take kindly the counsel of the years, gracefully surrendering the things of youth.
Nurture strength of spirit to shield you in sudden misfortune. But do not distress yourself with dark imaginings. Many fears are born of fatigue and loneliness.
Beyond a wholesome discipline, be gentle with yourself. You are a child of the universe no less than the trees and the stars; you have a right to be here.
And whether or not it is clear to you, no doubt the universe is unfolding as it should. Therefore be at peace with God, whatever you conceive Him to be. And whatever your labors and aspirations, in the noisy confusion of life, keep peace in your soul. With all its sham, drudgery and broken dreams, it is still a beautiful world. Be cheerful. Strive to be happy.
The Lyman-alpha transition occurs when an electron in a hydrogen atom transitions from the first excited state (n=2) to the stable ground state (n=1), emitting an ultraviolet photon at 1215.67 Å. This and the other Lyman transitions to the ground state are named after American physicist and spectroscopist Theodore Lyman (1874-1954) who discovered and studied these spectral lines.
About 75% of the mass of our universe is hydrogen, so when we look at a very distant object, such as a quasar, the light from that distant object passes through a large number of tenuous hydrogen clouds between us and the distant object. The cooler hydrogen clouds absorb ultraviolet light at a wavelength of 1215.67 Å, so this wavelength is “removed” from the light from a distant object, as evinced by an absorption line in the spectrum of the distant object. But because the intervening neutral hydrogen clouds are moving at different speeds and cosmological redshifts, a number of different wavelengths have light removed (as seen from Earth), resulting in what is known as a Lyman-alpha forest. Analysis of the Lyman-alpha forest can tell us much about the neutral hydrogen clouds between us and any distant extragalactic source.
When a hydrogen cloud atom absorbs a 1215.67 Å ultraviolet photon, its electron jumps from the n=1 ground state up to the n=2 first excited state. However, excited electrons can’t stay in the n=2 state for long, and quickly return to the ground state again, emitting a photon of light at 1215.67 Å. So, why do we even see an absorption line? Yes, ultraviolet photons from the distant extragalactic source are removed from our line of sight by an intervening hydrogen cloud, but when ultraviolet photons are re-emitted, the photons radiate in all directions, and only a few travel towards us along our line of sight. The net result is an absorption line.
Even though the population of Dodgeville, Wisconsin is only around 4,800 people, there is quite a bit of traffic congestion along Dodgeville’s only real north-south through street: Iowa/Bequette, otherwise known as Wisconsin State Highway 23.
You’d never know it just driving through town, but the south part of WI 23 in Dodgeville is Iowa St. (S. Iowa St. south of Division St. and N. Iowa St. north of Division St.), and the north part of WI 23 is Bequette St., with the dividing line being Spring St., an unholy mess of an intersection that also includes Main St. and Diagonal St. (signed as Ohio St.). This is the perfect candidate for a roundabout if I ever saw one.
Making a left turn onto Iowa St. (which we often have to do) can be nerve-wracking with traffic, pedestrians, and in places poor visibility due to parked cars. A good way to solve this problem (and reduce the likelihood of accidents) would be to have one intersection along Iowa St. that has a traffic light. I think the ideal location for a traffic light would be the intersection of N. Iowa St. and Merrimac St.
Our current best estimate for the age of the universe (as we know it) is 13.799 Gyr ± 21 Myr. The Great Flaring Forth (GFF) occurred 13.8 billion years ago, and the universe has been expanding and cooling ever since.
The background temperature of the universe is today 2.72548 ± 0.00057 K. “K” stands for Kelvin, a unit of temperature named after William Thomson, 1st Baron Kelvin (1824-1907) – Lord Kelvin – who championed the idea of an “absolute thermometric scale”. A temperature in Kelvin is equivalent to the number of Celsius degrees above absolute zero. Put into terms we may be more familiar with, the cosmic background temperature is -270.42452° C, or -454.764136° F. While in the absence of nearby stars or other energy sources, the universe is certainly cold, scientists have artificially produced temperatures as low as 100 pK (1 picoKelvin = 10-12 K).
Using Wien’s displacement law, we can calculate the wavelength of electromagnetic radiation where the background universe is brightest.
So, we see here that the background universe is “brightest” in the microwave part of the radio spectrum, at a peak wavelength around 1 mm. Using the relationship between frequency and wavelength, c = νλ, we can determine the microwave frequency where the background universe is brightest.
Microwaves at this frequency are in the extremely high frequency (EHF) radio band, above all our allocated communications bands (275-3000 GHz is unallocated).
Of course, a significant amount of emission occurs either side of the peak, particularly at longer wavelengths and lower frequencies. (The background universe radiates with an almost perfect blackbody spectrum.)
There are several ways to define the wavelength/frequency of maximum brightness. The above is one. Depending on the method we choose, the peak wavelength lies between 1.0623 and 3.313 mm, and the peak frequency between 90.5 and 282.0 GHz.
Wouldn’t it be nice if you got to choose where some of your income tax money goes? Where you the taxpayer have some say in how your hard-earned tax dollars are allocated?
Here in the dis-United States, about 50% of us want lower taxes, and 50% of us would be receptive to higher taxes provided that it pays for things we believe in like universal health care and low-cost or no-cost education.
Short of amicably splitting up our country (a civil separation), changing our tax policy may help alleviate some of the frustration many of us have that half of the country is keeping us from building the kind of country we want for ourselves and for our children.
Federal income tax, and state and local income tax (where in effect) would be divided into a non-discretionary portion (100% currently) and a discretionary portion.
When you fill out your tax return each year, you would designate the government agencies and programs where you want the discretionary portion of your taxes to go.
Going one step further, I would like to see taxpayers given the option to choose either the standard or a supplemental tax tier. Those who opt to pay higher taxes by choosing the supplemental tax tier would pay a fixed percentage more, regardless of income (like a true flat tax).
To be fair, those paying in at the higher supplemental tax rate should receive additional benefits compared to those paying in at the standard rate. This could mean lower medical costs, lower education costs, or increased social security payments during retirement, for example.
Would this be easier to implement than partitioning the U.S.? Perhaps. Would it be the more effective solution to satisfy those with very different viewpoints about the proper role of government? Perhaps not.
In my view, society is far too reliant on volunteers. If a job is worth doing, and if it is a benefit to society, then, more often than not, it needs to be a paid position. There is so much work of a humanitarian, educational, and environmental nature that needs to be done that cannot and will not be done by any capitalistic enterprise. As members of society, we all have an obligation to help fund these activities through strong government and non-sectarian non-profit partnerships.
I dream of a day when paying for our medical care is no longer tied to having health insurance through an employer, when each of us will have the freedom to work in a variety of capacities, for both profit and non-profit organizations, throughout our careers, and to receive adequate training and pay for those efforts.