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Comment: Re:Um, they're going to be awful this year (Score 2) 31

by StupendousMan (#47635801) Attached to: The Meteors You've Waited All Year For

When the Moon is full, it rises at sunset and sets at sunrise. Each day, the Moon rises (and sets) about one hour later. So, 2 or 3 days after the full Moon, the Moon will rise 2 or 3 hours after sunset, and set 2 or 3 hours after sunrise.

Which means that, after midnight, the Moon will be high in the sky, ruining the view of the Perseids. It will not "set several hours before dawn."

In short, the response above is wrong.

Comment: False alarm -- just a normal background source (Score 5, Informative) 129

by StupendousMan (#47107299) Attached to: The Andromeda Galaxy Just Had a Bright Gamma Ray Event

The team which announced the event has now figured out that it wasn't interesting after all:

NUMBER: 16336
SUBJECT: Swift trigger 600114 is not an outbursting X-ray source
DATE: 14/05/28 07:57:12 GMT
FROM: Kim Page at U.of Leicester

K.L. Page, P.A. Evans (U. Leicester), D.N. Burrows (PSU), V. D'Elia (ASDC) and A. Maselli (INAF-IASFPA) report on behalf of the Swift-XRT team:

We have re-analysed the prompt XRT data on Swift trigger 600114 (GCN Circ. 16332), taking advantage of the event data.

The initial count rate given in GCN Circ. 16332 was based on raw data from the full field of view, without X-ray event detection, and therefore may have been affected by other sources in M31, as well as background hot pixels. Analysis of the event data (not fully available at the time of the initial circular) shows the count rate of the X-ray source identified in GCN Circ. 16332 to have been 0.065 +/- 0.012 count s^-1, consistent with the previous observations of this source [see the 1SXPS catalogue (Evans et al. 2014): http://www.swift.ac.uk/1SXPS/1....

We therefore do not believe this source to be in outburst. Instead, it was a serendipitous constant source in the field of view of a BAT subthreshold trigger.

This circular is an official product of the Swift-XRT team.

Better luck next time.

Comment: For reference, here's one of the current systems (Score 4, Informative) 38

by StupendousMan (#46454985) Attached to: NASA Offers Bounty For Improved Asteroid Detection Algorithms

If you're interested in the current state of the art, read this article from the Publications of the Astronomical Society of the Pacific (April 2013). It describes the hardware and software used by the Pan-STARRS team to detect asteroids automatically in data taken with their 1.8-meter telescope on Hawaii and its 1.4-gigapixel CCD camera.


Comment: A page with technical details (Score 5, Informative) 107

by StupendousMan (#43632557) Attached to: Fermi and Swift Observe Record-setting Gamma Ray Burst

I wrote up a short summary of the observational details for one of my classes -- you can find it at


You can also follow a nice summary of the latest results by following Don Alexander's thread on the Cosmoquest forum:


Comment: Re:Neutrinos? (Score 2) 69

by StupendousMan (#39425373) Attached to: Possible Supernova In Nearby Spiral Galaxy

First, this is a type Ia supernova, which produces fewer neutrinos and a much smaller gravitational wave signal than a core-collapse supernova.

Second, any supernova in a galaxy beyond the Local Group (the Milky Way, the Andromeda Galaxy, and some smaller companions) is too far to produce enough neutrinos or gravitational waves to be detected by our current instruments.


Comment: Re:I teach physics in a workshop, not lecture ... (Score 1) 212

by StupendousMan (#38580844) Attached to: When Getting Rid of College Lectures Makes Sense

The "expensive AV stuff" is 2 projectors per room (we need to project onto opposite walls because students sitting at tables aren't all facing in the same direction), times 7 workshop rooms. 14 projectors cost a lot to maintain.

Yes, we've completely eliminated traditional labs from the introductory physics sequence.

There is a small amount of data on how students did on the FCI before and after the switch, but not enough to be significant. I don't think that the FCI is a very good way to measure the knowledge of a student in physics, by the way.

When I said "move away from the median student", I mean "teach at a level which is far from that appropriate for the median student." In a lecture, one can choose to go faster or deeper, knowing that one may leave most of the class behind; the lack of feedback makes it easy. In a workshop, because one is so close to the students, one sees the effect and it's hard to ignore it. The question of "should one teach to the level of the median student" is a big one, of course, and I can't address it here.

Comment: I teach physics in a workshop, not lecture ... (Score 4, Interesting) 212

by StupendousMan (#38578670) Attached to: When Getting Rid of College Lectures Makes Sense

... and it's okay.

At RIT, we switched from the traditional lecture + lab approach to the "workshop" approach about six years ago. The students meet in a room with small tables and maximum class size of 42, three times a week for two hours each. The room has equipment at all the tables, so that students can quickly set up small experiments which may not take the entire 2-hour meeting.

I taught in the traditional manner for about seven years, and in this manner for an equal duration. Does the workshop have advantages? Sure: students are less likely to fall asleep because they are often working examples, and because they are in a small, well-lit room. I can walk around and talk to individual students for a minute or two at a time, so I can find those who are having problems and try to help them. It's easy to introduce a concept, give one simple example, then ask the students to do another example, within a span of 20 or 40 minutes. In some cases, this cycle of introduction - observation - action may help students to understand or remember the material.

But there are disadvantages, too: in a workshop, it's difficult to move away from the median student. I can't go too much faster or deeper, because it's clear that many students are not getting it; so some students are held back. I can't slow down for the slowest learners, either, because it becomes obvious that the majority of the class is bored. This approach is MUCH MORE EXPENSIVE than the traditional one, because we need to offer 10 or 15 sections of the class each quarter; that means a lot more faculty time. The rooms can't be used for any other classes, and the AV requirements are pretty steep -- we need to spend around $10K just on projectors each year. We need more equipment than we would have in traditional labs, and that stuff isn't cheap.

It's not clear that this approach causes students to learn any better; some are helped, some are hurt. It's difficult to compare student achievement in workshops vs. lectures, because at the same time that workshops were introduced, we changed the content of our classes as well.

My summary, after years of experience: not a silver bullet, a lot more fun to teach, more expensive overall.

Comment: I'm a professor. What do I gain by going online? (Score 1) 261

by StupendousMan (#37522874) Attached to: Should College Go Online?

I teach at a large university. My university is pushing for faculty to sign up for on-line courses. My guess is that they see two economic incentives: they can appeal to a larger customer base -- students who can't attend in person -- and they can cut costs by increasing the number of students enrolled relative to the number of professors.

What's in it for me? What do I gain by agreeing to teach on-line? I lose the give-and-take relationship with my students; how can I see if my explanation of a new concept is working if I can't see the expressions of the students as I try to explain it? I contribute to putting myself and my colleagues out of a job. I implicitly support the idea that the best way to teach is to give students videos to watch.

Actually, all of my course materials ARE on-line already. See http://spiff.rit.edu/classes. Anyone who wants to use these materials to teach himself -- go for it! So I'm not lazy, and I'm not trying to keep knowledge secret. I just think that teaching college students in person is better than doing so via web pages and videos.

Comment: Re:Close, like real close (Score 5, Informative) 141

by StupendousMan (#37218486) Attached to: 'Instant Cosmic Classic' Supernova Discovered

Alas, we shouldn't expect any neutrinos to be detected from this event. I am an astronomer who studies supernovae, and the Type Ia events --- those due to a runaway thermonuclear reaction inside a white dwarf --- do _not_ produce the same sort of giant burst of neutrinos as core-collapse events.

In addition, this supernova is much, much farther away than SN 1987A. This event, in M101, is about 6400 kpc away, while SN 1987A was only about 50 kpc away. So, in very rough terms, the new SN is about 100 times farther away ... which means than the flux of particles from it will be about 100*100 = 10,000 times weaker than that from an object at the distance of SN 1987A. We only detected about 30-40 neutrinos in total from SN 1987A, so, even if this new supernova was a core-collapse event (which it isn't), we might only expect 40/10,000 = 0.004 neutrinos to be detected.

Yes, yes, today's neutrino detectors are larger than the ones operating in 1987. However, I don't think they could make up this sort of difference. And remember, a Type Ia supernova doesn't produce as many neutrinos to start with.

But this should be a good object for people to see through telescopes or (possibly) binoculars!

Comment: Wikipedia irrelevant for Physics positions (Score 3, Insightful) 139

by StupendousMan (#35755886) Attached to: Editing Wikipedia Helps Professor Attain Tenure

We're in a job search right now for two tenure-track professors in a Physics Department. None of the five candidates interviewed so far has mentioned Wikipedia. I'm pretty sure that if one did, he wouldn't gain any credit by doing so.

Our department made recommendations for a tenure decision earlier this year. No mention of Wikipedia in the supporting materials for that candidate, nor have I ever seen such a mention. I am pretty sure that neither my colleagues nor the administrators involved in granting tenure would give any credit for editing Wikpedia.

Comment: Start with the Moon (Score 1) 377

by StupendousMan (#31090996) Attached to: What Objects To Focus On For School Astronomy?

I teach astronomy courses to university students. The best object by far to look at is the Moon, as others have said.

  1. it's big and bright, so you can't miss it
  2. students can compare the view through the telescope to the view with their naked eyes
  3. students can compare the view through the telescope to the view through binoculars

I've written a number of outdoor lab exercises for introductory astro students which would be perfectly appropriate for your students. You can read one on the Moon, in particular. Or you can look at the lists of exercises in this class or this other class for more ideas.

I'd recommend the "Limiting Magnitude" exercise as one which you can do when the Moon isn't up. It will help if you have several pairs of binoculars in addition to the telescope.

Good luck!

Comment: NOT first spectrum of planet's atmosphere (Score 4, Informative) 32

by StupendousMan (#30791134) Attached to: Spectrum of Light Captured From Distant World
Astronomers have measured transmission spectra of a planet circling the star HD 209458 and a planet circling the star HD 189733 (and probably others). The first successful measurements, which found sodium in the spectrum of HD 209458b, were published by Charbonneau et al. in 2002. See ApJ 568, 377 (2002).

"Mach was the greatest intellectual fraud in the last ten years." "What about X?" "I said `intellectual'." ;login, 9/1990