13 October 2009

This is why we have SI

I have a bottle of a nasal spray that I'm using for allergies, and it says on the label that each spray delivers "50 mcg" of the drug. What in the world is a "mcg"? Do you think they mean μg (microgram), which is 10-6grams, or in SI units a single spray would be delivering 5*10-8kg of drug, or do you think they mean m-c-g (milli-centi-grams), which would be 10-3*10-2grams =10-5grams, or in SI units a single spray would be delivering 5*10-7kg? These are two different values depending upon how I read the label, one of which is the actual amount of drug delivered and the other of which is either 10 times or one tenth the amount of drug delivered.

This is the whole reason we have metric prefixes in the first place, to reduce confusion and have a standard system whose meaning everyone agrees to. Good thing the actual quantity of the drug here doesn't matter to me, I just take my prescribed two sprays.

30 August 2009

Mt. Wilson Observatory threatned by fire

The Mount Wilson Observatory is home to the 100-inch (2.5m) Hooker telescope, one of the most historical telescopes in the era of modern astronomy. Following on the heels of the Harvard College Observatory Computers'1 work on classifying stars, the Henry Norris Russell used the Hooker telescope, and in conjunction with Ejnar Hertzsprung developed the diagram now known as the Hertzsprung-Russell (or HR) diagram, a diagram of as much importance to astronomy as the periodic table is to chemistry. More famously, Edwin Hubble used the Hooker when he discovered the expansion of the universe, disproving the leading steady state hypothesis (even espoused by Albert Einstein). It is probably even more important that Hubble first proved that all those fuzzy "spiral nebulae" were actually entirely separate galaxies, but we take that for granted today, while cosmologists are still working on the details of the universe's expansion.

So with this background about the Mt. Wilson Observatory under your belt, perhaps you will understand some of the fear I feel when I read that as of 5:42 PDT (8:42 EDT) the LA Times was estimating that the current wildfires outside LA would probably raze the observatory within hours. As of this writing (8:57 PDT / 11:57 EDT) the fires have not yet reached the observatory (though they are visible from the observatory webcam, link is to a screenshot of the webcam since the webcam server itself is overloaded). The director of the observatory reports that firefighters will be remaining in place on Mt. Wilson overnight, implying that it is safe enough to do so, and hopefully they will be able to keep fighting and save the historic observatory.

If you the most more up-to-date information that I have been able to find, follow Mike Brown's twitter feed @plutokiller (yes, THAT Mike Brown). If the observatory does burn down overnight, I'd appreciate it if someone txted me.

1 Also referred to as "Pickering's Harem,"2 after the fact that Harvard College Observatory Director, Edward Pickering, famously stated that his male graduate students were so inept that his maid could do a better. Following on the statement, Pickering did hire his maid (Williamina Fleming) and then a string of other women, hence the unflattering name for the group. Despite the name, these human "computers" did amazing work, revolutionizing the field of stellar classification.

2 The incidence of referring to both harems and hookers in the same post is purely coincidental.

Current music: "Cold Missouri Waters" by Dar Williams, et al.

25 August 2009

Noble Nobels

During WWII, two German Nobel Prize laureates (in physics) escaped to Denmark. When it too was taken over, their medals were chemically dissolved by Danish physicist Neils Bohr and Hungarian chemist George de Hevesy to keep them safe from the Nazis (and to keep the physicists safe as well, as taking gold out of Nazi Germany was a crime). The solution must have just looked like any other bottle of chemicals, because after the war was over, Hevesy precipitated the gold out of the solution, sent it back to the Swedish institution that grants the Nobels, and they generously recast the medals and reawarded them to the two physicists.

02 August 2009

Order of Magnitude

This image is truncated on the right, please click on it to see the full version!

With the power of science we can now calculate this! At least a rough number.

Let's say that teach morning you create a small bit of crud 1mm to a side, so 1mm by 1mm by 1mm, so the volume of this one bit of crud is 1e-9m^3 (or if you like to write things fancy, 10-9m3). Yeah you have two eyes, but this is a rough calculation, so I'm going to ignore that. I'm also going to ignore that you don't wake up with crud every day of your life. We do however need your lifespan, let's say 80 years approximately, 365.25 days per year, so you live 2.922e4 days, or let's round that off and say 3e4 days. Multiply the number of days you wake up, by how much crud you get each day, and voila, 3e-5m^3.

According to my favorite conversion website, a teaspoon has a volume of around 5e-6m^3, with the result that you actually produce around 6 teaspoons of eye crud in your lifetime.

12 July 2009

Professional Ethics in Astronomy

Reposted in its entirety from an AAS email.

The AAS has drafted a statement on professional ethics on June 7, 2009 (see below). AAS members are asked to login to the AAS Forum at


and provide comments. The comments will appear online after a moderator has approved them.

AAS Statement on Professional Ethics:
The mission of the American Astronomical Society is to enhance and share humanity's scientific understanding of the Universe. We believe the advancement of astronomy requires that we provide ethical guidelines for AAS members and, for that matter, anyone involved in professional astronomical activities.

Every astronomer is a citizen of the community of science. Each shares responsibility for the welfare of this community. We endorse the statement of the American Physical Society that "Science is best advanced when there is mutual trust, based upon honest behavior, throughout the community." All scientists should act ethically in the conduct of their research, in teaching and education, and in relations with both members of the public and other members of the scientific community. We have a special responsibility to students and postdocs to train them in ethical conduct.

The American Astronomical Society believes that the following are the minimal standards of ethical behavior relating to the profession.


All people encountered in one's professional life should be treated with respect. Discourse should be civil. Scientists should work to provide an environment that encourages the free expression and exchange of scientific ideas. They should promote equality of opportunity and treatment for all their colleagues, regardless of gender, race, ethnic origin, religion, age, marital status, sexual orientation, disabilities, or any other reason not related to scientific merit. This principle is clearly stated in our By-Laws.

More senior members of the society, especially research supervisors, have a special responsibility to facilitate the research, educational, and professional development of students and subordinates. This includes providing safe, supportive working environments, fair compensation and appropriate acknowledgment of their contribution to any research results. In addition, supervisors should encourage the timely advance of graduate students and young professionals in their career aspirations.

It is also incumbent on senior members of our society to inform more junior members of these ethical issues and of institutional and government guidelines, policies and precedures related to the oversight and maintenance of ethical standards for research and conduct. It is the responsibility of all members of our society to familiarize themselves with such guidelines, policies and procedures.


It is an ethical responsiblity that research results be recorded and maintained in a form that allows review, analysis, and reproduction by others. It is incumbent on researchers involved in large, publicly-supported studies to make results available in a timely manner.

Fabrication of data or selective reporting of data with the intent to mislead or deceive is unethical and unacceptable, as is the appropriation of data or research results from others without permission and attribution.

It should be recognized that honest error is an integral part of the scientific enterprise. It is not unethical to be wrong, provided that errors are promptly acknowledged and corrected when they are detected.


All persons who have made significant contributions to a work intended for publication should be offered the opportunity to be listed as authors. This includes all those who have contributed intellectually to the inception, design, execution, or interpretation of the research. Other individuals who have contributed to a study should be appropriately acknowledged. The sources of financial support for any project should be acknowledged/disclosed. All collaborators share responsibility for any paper they coauthor, and every coauthor should have the opportunity to review a manuscript before its submission.

Proper acknowledgement of the work of others must always be given, and complete referencing is an essential part of any astronomical research publication. Authors have an obligation to their colleagues and the scientific community to include a set of references that communicates the precedents, sources, and context of the reported work. Deliberate omission of a pertinent author or reference is unacceptable. Data provided by others must be cited appropriately, even if obtained from a public database.

All authors are responsible for providing prompt corrections or retractions if errors are found in published works.

Plagiarism is the presentation of others' words, ideas or scientific results as if they were one's own. Citations to others' work must be clear, complete, and correct. Plagiarism is unethical behavior and is never acceptable.

Authors, editors and referees should also be aware of the professional and ethical standards that have been adopted for the AAS journals ( http://aas.org/ethicsPolicy ).


Peer review is an essential component of many aspects of the scientific process such as evaluating research proposals, publishing research results, and evaluating colleagues for career advancement.

Peer review can serve its intended function only if the members of the scientific community are prepared to provide thorough, fair, and objective evaluations based on requisite expertise. Although peer review can be difficult and time-consuming, scientists have an obligation to participate in the process.

Reviewers should disclose conflicts of interest resulting from direct competitive, collaborative, or other relationships with those they are reviewing and recuse themselves from cases where such conflicts preclude an objective evaluation. It is unethical to seek to gain an advantage by means of reviewing the work of others.

Privileged information or ideas that are obtained through peer review must be kept confidential and not used for competitive gain.


Many activities of scientists and educators have the potential for a conflict of interest. Any professional relationship or action that may either be or be perceived as a conflict of interest should be fully disclosed. Most organizations or activities have mechanisms for managing conflicts, for example, through recusal. If a conflict of interest cannot be properly managed, the activity should be avoided or discontinued.

23 June 2009

The Ethics of a Mars Mission

One thing that keeps flitting into my head when we talk about a human mission to Mars, is the ethics of it. Right now we don't have the ability for anything but a one-way mission, and still I know there are people who would jump at the chance. I seem to recall reading that women astronauts are required to go on birth control, primarily to eliminate their periods, and this already seems like such an invasion of personal choice. Imagine a trip that takes 3 years each way. In a situation like this NASA really will have to take steps to prevent pregnancies, or to be able to deal with them should they happen.

The one aspect that popped into my head today though upon reading the above linked article by Buzz Aldrin is the issue of consent. The standard for experiments performed upon humans (and you can't call a trip to Mars anything but an experiment) is one of informed consent: the participants must be made aware of the risks (and the risks must be below a certain level), and the participants must give consent. Moreover, the participants have the right to with draw consent at any point in time. Missions on the ISS and such are already seriously pushing the boundaries on this one IMO (does the screening of astronauts beforehand allow NASA to get around the ethics board? or is NASA not subject to an ethics board?). How much more questionable in terms of withdrawing consent is a round trip to Mars? What about a colonization trip?

On the other hand, the worry about consent is another incentive for mandatory birth control and/or sterilization: children are unable to give consent, and it would be unethical to put an infant into the situation of a trip to Mars. I wonder at what point in colonization we will determine it is safe enough to allow children. And will the requirements be different for children transported to the colony vs. children produced in situ?

25 May 2009

North Korea's nuclear bomb test

I'm not a big fan of politics, but part of the story about North Korea's second nuclear bomb test caught my eye.

North Korea announced its underground nuclear test a little more than an hour after the U.S. Geological Survey reported a magnitude 4.7 seismic disturbance at the site of North Korea's first nuclear test. --CNN

And sure enough, here's the earthquake data from the USGS.

04 May 2009

Strike Two for California

A California high school history teacher has been found guilty of violating the First Amendment by calling a student's comments about creationism "religious, superstitious nonsense". Ouch! It gets worse.

In a December 2007 lawsuit, [Advanced Placement European history student, Chad] Farnan, then a sophomore, accused Corbett of repeatedly promoting hostility toward Christians in class and advocating "irreligion over religion" in violation of the First Amendment's establishment clause.

The establishment clause prohibits the government from making any law "respecting an establishment of religion" and has been interpreted by U.S. courts to also prohibit government employees from displaying religious hostility. --Scott Martindale, The Orange County Register

So government employees are not allowed to talk about non-religious alternatives.

It gets worse.

Corbett made his "superstitious nonsense" remark during a class discussion about a 1993 court case in which former Capistrano Valley High science teacher John Peloza sued the Capistrano Unified School District, challenging its requirement that Peloza teach evolution. --Scott Martindale, The Orange County Register

So yes, this comment really was in the context of a conversation about evolution and creationism. I will admit that how the teacher said it is quite disrespectful, but to call it the "establishment of (ir)religion?!" Are teachers not allowed to express personal opinion? The court found the school district not liable for the teacher's comments, so clearly this was the teacher's opinion, so if it was just his opinion how does it constitute the government establishing, because that's what the first amendment is about, the government And if it's the government doing the establishing, why is it the teacher is the defendant, and not the government?

And the part that I fear the most: does this mean my telling my science students that creationism is "not a scientific statement" is also violating the freedom of speech and separation of Church and State? Should I wipe my lecture on the origins of life on Earth in the context of astrobiology in the fear that a student will charge me with something?

This is just ridiculous.

20 April 2009

"Training the Next Generation of Astronomers"

An interesting article on how future astronomers are being trained, this article makes a few key points on the current process. (Full text available for free via the download links.)

For example, the current generation of grad students are being trained to perform research, when in reality most astronomers do not spend the majority of their time actually performing research. Most researchers instead are managers, grant writers, and are in charge of budgets, none of which are skills we learn as grad students.

In addition 11% of PhD earning astronomers go into EPO (Education and Public Outreach) careers, and many researchers also perform some component of EPO as well. Without EPO, the public would not have such a love for astronomy, congress wouldn't fund NASA nearly as much, and even the HST would have been retired a decade ago.

A large portion of the paper is also dedicated to the family unfriendliness of academia, making the point that this doesn't hurt only women, but also those men who wish to play a larger role in their families.

Give the article a read!

27 March 2009

Today Show on MSNBC screws up Equinox

As usual a news show tries to trump up how the Equinox is the only time you can balance an egg on end. This is entirely untrue, debunked by Phil Plait here and here. But that's not the fun part of the below video.

25 March 2009

Appeal to Authority

Logical fallacies are viewpoints brought up during arguments which appear logical on the surface, but when you dig a little deeper are in fact mostly unfounded. One common fallacy is the appeal to authority, where you assume that just because someone is an "authority," that they have to be right. For example, "Pope Urban VIII said that Galileo's views were wrong, so since I trust the Pope I'm going to agree with the Pope and say that the universe is actually geocentric." Sometimes the flaw is that the "authority" isn't actually authoritative in the topic in question - the Pope isn't an astronomer, the President of the US isn't a meteorologist, etc. But even if the "authority" is actually an authority, that doesn't make him/her automatically correct. Even authorities make mistakes - look at Tycho Brahe for example. This is also the entire point of peer reviewed journals, to give the authorities the chance to duke it out.

So that said, when the NY Times Magazine devotes a 28-screen-long article to singing Freeman Dyson's laurels as a motivation for us to listen to his arguments about CO_2 levels, I find myself quite disappointed. Dyson is an authority on quantum physics and sci-fi concepts (such as the Dyson sphere, which led to Larry Niven's Ringworld concept/series); he is NOT an authority on environmental science. I don't care how many people think he's a genius, he isn't a genius in this field. And even if he were, even authorities can make mistakes. It is NOT appropriate for the NY Times to promote an individual's ideas based solely upon that individual's reputation. If the article were billing itself as a biography of Dyson's life, it could be an excellent one, but the article is trying to give us a view of Dyson's ideas and as such it is a remarkably poor one.

I guess in the end by expecting the NY Times to live up to its reputation, I too am guilty of putting too much faith in authority.

22 March 2009

Belt of Venus

On an evening flight from Minnesota to Connecticut Friday evening, I finally saw the Belt of Venus for the first time. I didn't have my camera handy and photos through windows never come out well anyway, so here's a photo from a Google search:

The Belt of Venus is actually the Earth's own shadow cast in the sky. As you probably already know, the bright blue of the daytime sky is due to light from the Sun being scattered by dust in the atmosphere. When you take away that light from the Sun, what you're left with is a dark sky. The Belt of Venus appears on the Eastern horizon just after the Sun is sets in the West because the sunlight doesn't reach the Eastern horizon at that time. This is also why I suspect I haven't ever seen it previously - too high a horizon all around me where I live.

17 March 2009

Texas BOE to vote on Science Standards again

Once again Texas has reviewed and revised its state science standards, and once again they're trying to put in creationism. In this instance it's particularly bad because textbooks for the largest state in the US will be selected based upon these standards. If this bothers you, especially if you live in Texas yourself, here's some info on who to contact to complain and bring some sanity back into the process.

13 March 2009

Do we know basic science?

Unfortunately the answer is No. It's predictable that 31% of US adults surveyed said that dinosaurs and humans lived at the same time - thank you religious right! What's less comprehensible is that 47% didn't know the amount of time it takes the Earth to go around the Sun. IT'S A YEAR - THAT'S WHY WE HAVE THE YEAR IN THE FIRST PLACE.

Despite this complete ignorance, around 80% said that basic scientific research and education are important. Just not important enough for them to know any of it.

12 March 2009

"The Fair Copyright in Research Works Act"

The Fair Copyright in Research Works Act is supposedly intended to protect the intellectual property of scientists and their funding sources. Right now the NIH requires that all research funded by them be made available to the public for free after a certain proprietary period (in addition to their usual publication in peer-reviewed journals). Passing the bill would allow the NIH (and other federal groups such as the NSF, etc.) to remove this requirement from federally funded researchers, so that the researchers could choose to (or additional private funding sources could require them to) only publish their work in expensive peer-reviewed journals.

There is some debate about whether this is really as bad as it sounds. On the one hand, it sounds like the Act would allow the stifling of scientific communications and would mean that the American public would have to pay twice to see the work that their taxes paid for. On the other hand, it's my understanding that all federally funded research is required to be public domain and it's not clear that this Act would counteract that, or that the NIH and other federal groups would choose to do what the Act would allow. In addition, it might allow researchers to use multiple funding sources for a project which they may be unable to do right now - pharmaceutical companies may require NDAs for their work which the NIH regulations currently rule out since the researchers have to publish publicly.

Some links for more reading
The Act itself, Library of Congress
Phil Plait/Bad Astronomer's first post
His second post
A lawyer's opinion
Financial Times article

08 March 2009

Video hosting services?

Google Video is going to cease hosting new videos, so I need a new service to compress and host videos for my classes. Unfortunately Wikipedia's comparison charts of video services doesn't list all the things I want to know about. Here's what I'm looking for; the first few are required characteristics, "preferred" are additional characteristics I really want, and "optional" are bonuses.

  1. Unlimited file size (or at least 500MB), unlimited time (or at least 90 min)

  2. Cross-platform compatible

  3. No additional software required for viewing (things like Java, Flash are ok since most computers have them already)

  4. Compresses videos as well as sharing them, so they're faster for students to download on slow internet connections

  5. No bandwidth cap, or 1.5GB/week / 8GB/month minimum.

  6. Free to me and viewers

  7. No account required for viewing (preferred)

  8. I can choose not to display my name/account with videos I post (so I can use the same account for personal use) (preferred)

  9. I can choose to not allow students to find other videos that I posted (ditto the purpose) (preferred)

  10. I can choose to unlist videos I post, so no one but my students with a direct link are likely to find them (for intellectual property reasons) (preferred)

  11. Download of video available (preferred)

  12. Organization of videos into "folders" so I can post a link to the folder and the student can access all videos for that class in one place, and not the videos for other classes (optional)

  13. Tool to upload multiple videos simultaneously (optional)

  14. Upload tool allows me to resume paused or interrupted uploads (optional)

Anything else I should be looking for? Who do you like that has these? Google Video had 1-9. YouTube already fails at #1. I started looking at Vimeo and RapidShare, but don't know much about them. Edit: RapidShare seems a bit sketchy, Vimeo has weekly bandwidth limits below what I need.

28 February 2009

Windmill saves ski resort $450k/year

More land-using organizations should start putting up wind turbines, if the results from Jiminy Peak Mountain Resort in Hancock MA is any indication. Putting up a single turbine is saving them $450,000 per year, around 1/3 of their energy bill. Fortunately for them, the windmill produces the most electricity during the winter when it's the most windy, and seeing as they're a sky resort it's also when they use the most electricity (primarily due to their snow-making machines). (I can't help but think that if more companies used turbines, that we'd slow global warming and ski resorts wouldn't need to make fake snow as much.)

Also interestingly during the summer months the turbine produces more electricity than the Jiminy Peak uses. It appears they have not actually worked out a buy-back program for the excess electricity (where their utility company would actually pay *them* if they produced more electricity than they used), so instead the excess power goes into the grid - where it is then used up by local residents, reducing their reliance on the power company, on fossil fuels (coal burning is the primary source of electricity even in the Northeast US), and even their electricity bills. So this project has helped not only the ski resort, but also the local community.

Just don't tell the bats - the action of the turbine results in extremely low pressure air behind the turbine, which then results in internal bleeding. Shame that every improvement in one field leads to a problem in another. Time will tell whether the net good outweighs the net bad.

29 January 2009

Critical Thinking

I just ran across the following list of skills that comprise critical thinking.

* Evaluate and interpret the meaning of the textual material.
* Support a thesis with evidence appropriate to position and audience.
* Organize and connect ideas.
* View situations from different perspectives.
* Compare and contrast source material so that analysis can be made and theories can be proved or disproved.
* Draw inferences, suppositions, and conclusions from source materials.
* Perform a medley of solutions to a possible problem and present those solutions in a logical, coherent manner.
* Differentiate between fact and fiction, concrete and abstract, theory and practice.
* Make estimates and approximations and judge the reasonableness of the result.
* Apply quantitative and/or qualitative techniques, tools, formulas and theories in the solution of real-life problems and recognize when to apply those techniques, tools, formulas, and theories.
* Interpret data presented in tabular and graphical form and utilize that data to draw conclusions.
* Use quantitative relationships to describe results obtained by observation and experimentation.
* Interpret in non-quantitative language relationships presented in quantitative form.
* Apply the scientific method including methods of validating the results of scientific inquiry.

By these definitions, any course can be a critical thinking course! What do you think?

15 January 2009

Physics Today: Applying Title IX to Science Departments

The link is a reposting of a Physics Today article about applying Title IX criteria to college and university science departments.

14 January 2009

Naming the Sky

The second video in my series for my online course.

08 January 2009

What is Science?

I'm working on creating an online course that is the equivalent of my face-to-face intro astronomy course. Think of it as an "astronomy for poets" course, as there's very little math, and it's an overview course. Below is the first online lecture for it, or if the embedding doesn't work well for you, here's the direct link.

05 January 2009

Physics Limericks

Have I mentioned I love order of magnitude estimates?

How Fermi could estimate things!
Like the well-known Olympic ten rings,
And the one-hundred states,
And weeks with ten dates,
And birds that all fly with one... wings.

--David Morin, Harvard University

There's plenty more physics limericks on Dr. Morin's webpage or in his physics textbook.

Metric Conversions

When I teach the metric system, I try to help my students get a feel for metric units so they can do what I call a "sanity check" on every problem ("Does your answer make sense?"), but many still do better converting to Imperial units first. I think from now on I'll show them this graphic.

click through to original for alt text

04 January 2009

Mercury Falling

Look for Mercury tonight in the West after sunset. Jupiter will appear moderately bright and very close to the horizon. Venus will be brighter and higher in the sky to the South-West. And Mercury will be fainter near Jupiter, for about an hour after sunset. Make sure to find a low western horizon, or you won't see this at all.

I have yet to spot Mercury myself in the night sky, so I'm really hoping it stays clear tonight!