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Comment: Re:Hey congress... (Score 1) 409

by superluminique (#36679704) Attached to: Congress Dumps James Webb Space Telescope
Let me first disclose that I am a professional astrophysicist (though I'm not working in the US) so you know my bias right away ;-) All the budget arguments regarding the fact that it's a tiny drop in the sea (in comparison to the military allocation per say) make a lot of sense. As far as astrophysics goes, not having the James Webb Telescope will imply a delay in the science by at least a decade. I can understand the frustration with the fact that it's overbudget but even re-doing a stupid sidewalk seem to go overbudget... At the point where the project is, we are talking about hundreds of jobs depending on it and just as many people's career based on the fact that it is supposed to come online soon. It's not on the launchpad yet, but it feels like cancelling something once it's almost ready to go.

Comment: Re:sound like more mass covering laws that (Score 3, Interesting) 352

by superluminique (#33566368) Attached to: Canadian Government Muzzling Scientists
The answer is actually almost more simple than that.

I'm Canadian by the way and I'm really ashamed and pissed off by my government...

First of all, the Conservative Party of Canada is much more like the former Reform Party than the Conservative Party of the old days. There is a very strong base of religious nuts and redneck in the party who would do anything to deny actual scientific fact about too many things. Be it of religious reasons when it comes certain topics like geology/archeology/astronomy etc., and/or if it doesn't suit their own agenda such as for the global warming, pollution, geology, and that kind of things.

So far, we've got several nice demonstration of that. There was John Goodyear (I think I've got the name right), the science advisor to the minister, who turns out to be a conservative christian creationist who clearly doesn't believe in evolution. We've got John Baird, who as the Minister of Natural Ressources went to a big after-Kyoto conference and said that he never realized that global warming was an issue (clearly the government denies any environmental problems on taking place on this planet). One more for the road? No prob! The government pushing the purchase of replacement fighter jets for our old CF18 and pretty much buying new fighter jets them without asking anyone. A few days later, press conference with the Minister of Defense about the fact that two of our CF-18 escorted a Russian reconnaissance bomber away from the Canadian land. The plane was actually in the far away buffer and/or international zone and such kind of things happens a couple of times a year with not a single mention in the medias...

The whole game is very clear: they have their secret agenda and they're trying to sneak it in while the opposition parties are so weak, disorganized and without strong leadership that they aren't afraid that the opposition will make the government fall, unless they come with something big and blatant. So what they do is bringing a few big and controversial stuff along with a bunch of little sneaky things related to censorship for instance. They know opposition parties won't let go the big things so they play the arguing game a bit and give it up in a "package deal" that is like "ok, we're giving up the big piece but let's just not argue the little details".

Comment: Re:Disappointing nomenclature (Score 1) 55

by superluminique (#32758662) Attached to: Exoplanet Reports Exaggerated
I also wish we had nice names like in sci-fi movies. One of the problems is that most of the stars are designated by a number, like HD 2135 (for the stars from the Henry Draper catalog) or KIC 321 (for stars of the Kepler Input Catalog; Kepler being a satellite search transiting planets). There are also stars designated by their coordinates in the sky J1324-4355. For this reason, adding numbers at the end would make it confusing and letters are more appropriate.

Comment: Re:Sorry Bad Astronomer but you're partly wrong (Score 2, Informative) 55

by superluminique (#32753460) Attached to: Exoplanet Reports Exaggerated
The actual printed publication of 1RXS 1609 came out after that of Formalhaut but the results came up earlier. The reason being that Science and Nature (Formalhaut's was published in Science) have a much quicker turn around from the time the paper is initially submitted to the point where it comes out of press (it depends but it can be something like a month), whereas more specialized journals like the Astrophysical Journal in which 1RXS 1609's was published are extremely long (several months). Of course, no one in the field waits for the printed paper; typically they are put on ArXiV way before, most of the time after they have been accepted so that the authors know it has been referred and won't be modified further (there are still a few months between the time the paper gets accepted and it gets published). So, the 1RXS 1609 discovery came out and made up the headlines before, though again everything can be argued and I personally think it's pretty much a tie game. Bottom line, I don't say that Phil is all wrong, all I'm saying is that things are a bit more complicated that they look like. I hope it can help you understand. Cheers.

Comment: Re:Sorry Bad Astronomer but you're partly wrong (Score 2, Informative) 55

by superluminique (#32752122) Attached to: Exoplanet Reports Exaggerated

Sorry, I forgot to include the link to the 1RXS 1609 papers: the original "discovery" paper and the "confirmation" paper. So to answer your question, no this isn't the first publication about 1RXS 1609, the 2008 one did announce the discovery. And I don't think I'm changing my argument. Not sure exactly what the "boo" about published papers means but in my first post, when I talk about discoveries and findings I implicity (sorry if I didn't make it clear) refer to literature. Here, the point is simply that if someone noticed anything around Formalhaut before the 2008 paper, it hasn't been published or announced so then it's kind of irrelevant. Of course, it's irrelevant to the extent of what one considers a "first".

Anyways, one would probably agree that arguing about it is a bit pointless because there is no clear answer and it just becomes circular after a while. I personally know many of the authors on both the Formalhaut and the 1RXS 1609 teams, and I can say that I've witnessed very good ethics from them. For instance, during a talk one of them would refer to the discovery as the "first" with quotation marks and mention the other one as also being the "first". One last remark is that fact that peer reviewed journals usually forbid the use of words like "first" and such. Science and Nature are very strict about it and it's certainly a good thing because it alleviates unneeded arguments ;-)

Comment: Re:Sorry Bad Astronomer but you're partly wrong (Score 2, Informative) 55

by superluminique (#32750904) Attached to: Exoplanet Reports Exaggerated

Good point CheshireCatCO and I got stressed about talking too fast so I went and read the actual papers.

The thing is that this planet was only found last year, in a recent Hubble image. Astrophysicists saw it in the recent image and went back to the archives and also identified it in the 1995 archive image.

2004, according to Phil. And unless he's deliberately being misleading, they were in fact looking for the planet:

The 2004 actually refers to a 2005 Nature paper (A planetary system as the origin of structure in Fomalhaut's dust belt), presenting the modelling of the debris disk which strongly suggests that a planet has to be there. There is no mention of any candidate point source in the image.

(I, for one, can recall people identifying locations where a planet ought to be in that disk as early as Fall 2002. So it's credible to me that they'd be looking with HST in 2004.)

Granted, they didn't announce it right away. But, then, that's also the basis for you claim for priority of 1RXS 1609, so it seems like Phil is still right.

Of course, from the 2005 paper and strong prior evidence, they decided to follow up on the source and got images in 2006 and in 2008. Unless I missed the article there is not paper identifying a point source in the image as a candidate planet until the 2008 Science paper announcing the discovery of a planet around Formalhaut (Optical Images of an Exosolar Planet 25 Light-Years from Earth). If there was a peer-reviewed paper, it would be cited in the 2008 Science paper and, moreover, it is logical there is none since 1. they didn't want to be scooped, 2. they had to be cautious until the discovery was confirmed.

So even if people saw speckles in the debris disk of Formalhaut, it would have been difficult to claim them as planets unless spectroscopy would confirm or proper motion as it ended up being the case. In the case of 1RXS 1609, things are different since not only was there an optical detection but also a spectrum. The spectrum clearly showed it was a planet but could not unambiguously tell that it was gravitationally bounded to the star because of the lack of proper motion. So regardless of whether or not the planet was gravitationally bounded to the star (say, it could have been ejected from another system and just being running away), it still would have been, arguably, the first direct detection of an exoplanet.

Anyway, as everyone can see, the whole thing relies on what the definition of "first" is. Is it first published detection? First recorded image that shows it? etc. In any case, Phil does good work and I appreciate it. I just found that, ironically, the news about the news was being made a bit too spectacular.

Comment: Sorry Bad Astronomer but you're partly wrong (Score 4, Interesting) 55

by superluminique (#32749114) Attached to: Exoplanet Reports Exaggerated
I'm an astrophysicist and yes I find that most press releases about astronomy are somewhat exaggerated and have hyperbolic titles (it's probably true for anything about science). The obvious reason for that is to make them more attractive to the lay reader. I guess that something like "Imaging of 1RXS 1609 Companion Using Speckle Subtraction" would make people run away. Of course, there should be a compromise between sensationalism and news but it's not always obvious how to spin things the right way, especially when news writers barely know anything about science (believe me, I've had to deal with explaining relativity to the media).

Regarding this discovery, I don't agree with Bad Astronomer who seemed to have found a way to bash about "exaggerated scientific news" (as I said I do agree with him on the general statement). The other star that Bad Astronomer claims has been imaged in 1995 is Formalhaut. Yes, there is a point source somewhere in the debris disk around the star that is a planet. The thing is that this planet was only found last year, in a recent Hubble image. Astrophysicists saw it in the recent image and went back to the archives and also identified it in the 1995 archive image.

The exoplanet of the present discovery, around the star 1RXS 1609, has been found with direct imaging prior to the detection of the one around Formalhaut. I won't get into the details but all evidence were showing that it was an exoplanet orbiting that star. Of course, there is always a small chance of coincidence but the confirmation just came about -- this is what the news is about -- since clear orbital motion is now visible. So, technically, 1RXS 1609b was the first exoplanet to be formally identified using direct imaging, though Formalhaut's exoplanet had been photographed before without people recognizing it. Off course, this whole /. and Bad Astronmer's news is all about nitpicking on words. It's even hard for astrophysicists to unambiguously decide which one should be first. My last sentence would simply be that this /. post title "Exoplanet Reports Exaggerated" is totally hyperbolic and exaggerated since I was sure that it was reporting about something really bad like half the exoplanets are in fact not real or something like that...

Comment: Re:Any armchair physicists here? (Score 3, Informative) 190

by superluminique (#29433997) Attached to: A Galaxy-Sized Observatory For Gravitational Waves
DarrenBaker, a gravity wave is not a change in the gravitational constant; it is a deformation of the space-time fabric itself. So it doesn't change the gravitational (attractive) force between masses but simply moves the "fabric" on which they lie.

Imagine a stretchy, rubber fabric that you pull/push or move upward/downward from one side such that a wave propagates through. Then two masses lying on this fabric, link ping pong balls that you would stick on, would move closer/further apart. That's basically the effect that people are trying to measure. Of course, if these "test" objects are perfect in such that they're infinitely small, everything behaves in a trivial way. The catch is when your object is not "perfect" anymore and possesses some finite size. This seems to be concept that you worry about and you are right. Because of it's finite size, the object itself would change size. However, it does not matter at all because this change is not significant. Here's why:

The amplitude of a gravity wave is express in a weird unit expressing the ratio of the spatial compression in one direction to the stretching in the orthogonal direction (see the nice animation here). A typical gravity wave would have an amplitude of 10^-20., which basically mean that any object would change size by this fraction. So this is practically undetectable unless you consider something really big like the "arms" of the LIGO gravity wave detectors or this pulsar timing array. The other thing to take into account is the fact that what you are trying to detect acts like a wave. Waves that this pulsar array is after have frequencies of nanohertz, or wavelengths of 3*10^17 meters (this is about 32 light-year!). For LIGO, frequencies are the order of 1 hertz, so 300 000 km. Hence if your object, the pulsar for the pulsar array, or the mirror/detector for LIGO is much smaller that the wavelength that you attempt to detect, it really doesn't have any effect on what you are trying to measure.

Comment: Re:I think I see the problem. (Score 1) 553

by superluminique (#29146577) Attached to: Initial Tests Fail To Find Gravitational Waves
In fact that's what do they all the time, although they don't do it for the same reason that you were thinking about ;-) They typically run it for a couple months and then shut it down for a while to do some more calibration, tweaking and improvement. These results are from the fifth run.

Comment: Recuperate methane? (Score 1) 366

by superluminique (#28457403) Attached to: Cows That Burp Less Methane to Be Bred
I know it's probably a silly idea but since a lot of cows (at least milk cows) spend most of their time inside, wouldn't there be a way to have the air circulation system go through some kind of filter that would recuperate methane? Instead of just wasting it in the atmosphere farmers could at least use it as an energy source that would allows them to save electricity, which comes -- at least partly -- from fossil fuel?

BTW what's the status of methane recuperation from the big stacks of stinky manure sitting outside barns?

Comment: Re:How far out is 1.5 million miles? (Score 5, Informative) 84

by superluminique (#28341897) Attached to: Herschel Space Telescope Opens For the First Time
Hubble and Herschel's orbits are not even comparable to each other.

As pointed out earlier in a separated thread, Hubble is in a low, circular orbit about 560 km above the Earth. It has has a low inclination -- about 28 degrees with respect to the equator. You can actually see the orbital details and where it is in the sky on Heavens Above. The low Earth orbit was chosen so that the space shuttles could service it as they can't reach very far orbits basically due to limitation i how much fuel they can carry (bear in mind that at launch the shuttle engines are powered by the huge orange tank attached to it). It would have to be double checked but I think that the low orbital inclination was decided because it's was easier to launch -- Hubble is one of the most massive payloads ever carried by a space shuttle -- since you benefit from the fact that the Earth rotates so it effectively adds up to your velocity whereas for a polar orbit the contribution is basically null.

On the other hand, Herschel is orbiting 1.5 million km away from the Earth at the L2 point, in a direction opposite to the Sun -- the Sun - Earth - Herschel system forms a straight line. To give you an idea of the scale, the Earth-Moon distance is about 385 000 km so Herschel is located 3.9 times further. Therefore it's easy to understand why the mission is a one-hit wonder because there is no way someone is gonna go there fix it. To be more precise, Herschel is actually "orbiting" about the L2 point (see this diagram on Wikipedia) otherwise its orbit around the Sun-Earth-Moon system would be too unstable. The main reason for sending Herschel so far away from Earth is to optimize its infrared performances. Herschel observe at very long infrared wavelengths compared to, say, the the infrared camera of Hubble and near the Earth, even though you are in space, there is still a lot of thermal radiation coming from the Earth as well as the radiation belts that add up on top of what you want to detect. By being further away, passive cooling helps you and the liquid helium that keeps you cryostat cold heats up slower so your instrument has a longer life time. Also, "temperature" fluctuations are much smaller out there whereas they can be quite large near the Earth depending if your in the Earth shadow, crossing a radiation belt, etc. More stable environment means smaller systematics, which, in turns, imply better telescope sensitivity.

Finally, note that Hubble's successor, JWST will also hang out around L2 for similar reasons.

"Why should we subsidize intellectual curiosity?" -Ronald Reagan

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