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19 February
2011

Asteroid 2011 CQ1 came very very close to hitting the earth just a few hours after it was discovered on February 4 at 19:39 UT (14:39 EST). It came within a distance of 0.85 Earth radii (5480 km) over the Pacific Ocean. By astronomical standards, that is a really small distance! The image shows how severely it's orbit was changed due to it's close exposure to Earth's gravitational field.

Although the object was only about a meter in diameter (and thus not very threatening) the closeness of the approach prior to detection is unnerving. I don't think any other object has been recorded coming as close to the Earth without hitting it.


By Gregory Dudek at | Leave a comment |    
18 September
2011

Today I gave a one-hour talk at the IEEE 9th International Symposium on Robotics and Sensor Environments (ROSE). I talked about our work in underwater robotics (as I often do) and specifically dealt with summarization, terrain identification and a tiny bit about human-robot interaction.

One of the components of the talk was work by my former student Philippe Giguere, now a professor and Laval University in Quebec City. He was in the audience which made that part of the presentation feel a bit weird to me -- here I was reminiscing about work he had done with me and almost sharing the odd inside joke with him while this audience was listening. It was a very nice audience and they asked a lot of good questions, which left me with a generally positive vibe. Not a bad way to start a Sunday morning, after all!

The key coauthors of the work I presented, in addition to Philippe, are Yogesh Girdhar and Junaed Sattar.

The summarization part of the talk is covered (at a very high level) in my TEDxMcGIll talk shown here.




By Gregory Dudek at | Leave a comment |    
04 March
2012

This is not so good, but not too worrisome either. On Feb. 15, 2013, just under a year from now, a significant earth-grazing asteroid will come very close to Earth and has a small but non-negligible chance of hitting the earth and doing serious damage. While such an event could theoretically be averted using appropriate technology that could be build today, mankind has not build it and thus nothing can be done at this late date.

The culprit is a 35 - 80m wide asteroid labelled 2012 DA14 and it will make a near pass (27 thousand km or 0.00018 AU), with possible earth collision, travelling at 8.13 km/second on the 15th February, 2013 @ 19:26 UT. This distance is roughly a mere 4 times the earth's radius, and could result it a hit. For comparison, the distance between the Earth and Moon is 384K km or 0.0026 AU.

SInce the asteroid was discovered just 8 days ago (late Feb .2012) the accuracy of the estimate is not that high.

The asteroid is not big enough to be a planet killer though, and chances are nothing will happen at all, but it could make one heck of a big hole if it hit. On the Torino and Palero scales for this kind of risk, it;s not rated as at all scary. Palermo Scale values between -2 and 0 indicate situations that merit careful monitoring, and this one is a -4 on this logarithmic scale.

This link to the JPL LEO page gives the most accurate details and is updated as data is acquired.


By Gregory Dudek at | Leave a comment |    
18 March
2015

In order to know whether you have a chance of seeing an aurora, you need to know the level of geomagnetic activity at the time you are viewing.

These links provide relevant information.

Kp = [0,9] = geomagnetic activity for a 3-hour period.

http://www.swpc.noaa.gov/communities/space-weather-enthusiasts

Geomagnetic activity:

http://www.swpc.noaa.gov/products/wing-kp

Montreal's required Kp = 6 (dark sky outide the city) [ Magnetic latitude 54]

OVATION An empirical model of the intensity of the aurora. The model uses solar wind conditions (that is, the charged particle flux) and the interplanetary magnetic field at the Lagrangian point (L1) point as inputs.

3 day prediction:

http://www.swpc.noaa.gov/products/aurora-forecast-%E2%80%93-3-day-experimental

30 minute forecast:

http://www.swpc.noaa.gov/products/30-minute-aurora-forecast

Space Weather Alerts http://www.swpc.noaa.gov/alerts/index.html

Space Weather Alerts and Warnings Timeline http://www.swpc.noaa.gov/products/alerts-watches-and-warnings

Moon phase http://aa.usno.navy.mil/data/docs/MoonPhase.php

Aurora Forecast http://www.gi.alaska.edu/AuroraForecast

Solar Activity Index (Norway) http://flux.phys.uit.no/cgi-bin/HistActIx.cgi?site=tro2a&site=nal1a&site=dob1a&month=01&year=2009&submit=submit&RealTime&Simple&

Current Space Weather (ESA) http://swe.ssa.esa.int/web/guest/swe

Solar images: http://www2.hao.ucar.edu/mlso/mlso-home-page


By Gregory Dudek at | Leave a comment |    
25 March
2012

A senior Canadian government biologist has leaked proposed changes that would weaken Canada's protection for fish habitats, and thus the environment in general. Over 600 (real) scientists, many with very senior academic credentials, have signed a petition to complain about what they refer to as a highly destructive planned policy.

The government responded that existing policies "do not reflect the priorities of Canadians" (what baloney!), but the suspicion is that this is one step in clearing environmental obstacles to the oil sands pipeline. This has gotten very little press and warrants real attention before it's too late.

The key reality it that a major reason of species decline, especially in Canada, is habitat destruction. This is insanely shortsighted policy. The revised legislation is due March 29, 2012.

For more see the CBC article.


By Gregory Dudek at | Leave a comment |    
30 July
2012

The Canadian Federal government has earned a reputation in the scientific community (and perhaps more widely) for secrecy, heavy handed management of the media, and over-emphasis of private interests over public ones. This is most conspicuous in the way they have dealt with science policy, Federally funded science labs, and their own staff. The most recent example of this can be seen in the latest federal budget and the way in has altered science funding.

The Canadian National Science and Engineering Research Council (NSERC) provides money for basic and applied science research. While it budget is allocated is not particular large by international standards, it was widely recognized as doing a very good job. A particular strength of the system has been the Discovery Grant program which provides moderate-to-small amounts money to researchers based on their track record and plans for the next five years. The big strength of this program was that it provided fairly stable funding that allowed scientists and engineering who displayed good performance a lot of discretion to continue to do good work, without a lot of administrative overhead. Like any big government system, it had it's critics, but both nationally and internationally people recognized that it was among the best programs in any country in terms of how it was administered and how decisions were made. As a department head, the acknowledged strength of this program helped me to recruit great new people to Canada as professors, even though the total dollar amounts available are not that large.

In the last federal budget, NSERC was told to shift resources from this very


By Gregory Dudek at | Leave a comment |    
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