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Comment: Link to the full article, freely available ... (Score 4, Informative) 21

by StupendousMan (#49483471) Attached to: Spitzer Space Telescope Finds New Planet

... thanks to arXiv:


This event is VERY interesting and unusual because the microlensing event was observed from two very different places: on Earth, and from the Spitzer Space Telescope, which is many millions of km away from the Earth. Gravitational lensing occurs when a background star and a lensing star line up exactly in the same direction, as seen from an observer. Because Spitzer was so far away, it saw the lensing star line up with the background star first; then, as the lensing star moved in its orbit around the center of the Milky Way, the lensing star eventually lined up with the background star as seen from Earth, about 18 days later.

This lag in time between two widely separated observers seeing a lensing event will help us to figure out exactly how the two stars involved in the event were moving, and where they are, and other properties. Since most telescopes are located on Earth, in basically the same place, we almost never get this extra information.

Rah, rah, Spitzer! Rah, rah, OGLE!

Comment: We just covered this paper in our class last week (Score 2) 43

by StupendousMan (#49469163) Attached to: Tracking the Weather On an Exoplanet

I'm co-teaching a graduate course on exoplanets, and we talked about this paper in one of our meetings last week. Here's the link to our discussion of "spectroscopy of exoplanet atmospheres:"


You can read all our materials at



Comment: Link to the full article, freely available (Score 5, Informative) 199

The summary has a link to a paywalled article (silly Ethan). The full article is freely available to all on the arXiv preprint server:


I'm peripherally involved with the supernova field, though I study only the nearby examples. There has been for years the understanding that IF a difference should arise between the nearby events that we can study well, and the distant events which appear dimly and vaguely, AND if we did not realize that such a difference existed, THEN we could reach incorrect conclusions.

Scientists in the field have worried about this for years. It's not a sudden new realization.

It's very pleasant to see that a space telescope -- SWIFT -- which was built to study one type of object (gamma ray bursts) has turned out to provide vital information on a different type (supernovae). Since it is in space, it can detect ultraviolet light, and so show us that some nearby supernovae emit different amounts of ultraviolet light, even though they appear similar in the optical region. This UV difference hints at differences in chemical composition between supernovae, which may indeed be significant when we try to study very distant events with other telescopes.

Fortunately, light from those distant events is redshifted into the optical regime, so we can use very large ground-based telescopes to see the same UV light and compare it to the nearby events.

It's a very interesting field to follow: things change on timescales of 3-5 years. And yes, we are more aware of the uncertainties in the business than some news articles might imply.

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.

"If you want to eat hippopatomus, you've got to pay the freight." -- attributed to an IBM guy, about why IBM software uses so much memory