I have had custom silicone moulds for my earphones for almost 10 years and it was one of the best investments I've ever made. The earphones are Etymotic ER4P's and the moulds were made by the Dutch company, Elacin, following the traditional route, i.e. having deep canal impressions made by an audiologist. Elacin work closely with Etymotic, so made moulds to specifically fit their earphones: while I don't see this particular service offered on their website anymore, my experience with them was that they're happy to talk to customers and do what's necessary.
The fit is of these moulds is perfect, the external sound suppression impressive, and the internal sound spectacular, thanks of course to the ER4P's. Together, this means I can listen to and enjoy music at low volumes, and for people around me, they hear absolutely no spillover.
Sure, the combined cost was daunting at the time: somewhere around €600. Ouch. But amortised out over 10 years already and potentially many years to come, it has been well worthwhile for the quality of the sound and the sealing off of the outside world when desired. Living in Holland with all its off-road, dedicated cycling paths, I can even make good use of them on my daily commute.
If I had one complaint about them, it'd be the way that the piezo drivers of the Ety's protrude, making it impossible to place your ear on a pillow with the earphones in. I fly a lot and would like to be able to sleep with the earphones in, suppressing sound and perhaps playing something ambient.Perhaps I should splash out again and get something like high-end Ultimate Ears earphones, where the custom moulds and electronics are integrated into a "flatter" package...;-)
I realise that the title of this article was carried over from the CBC article, but could we at least try to remember that it's astronomers that discover things like this high-redshift galaxy, not an administration like NASA in isolation? I don't mean to diminish the absolutely central role played by NASA in both Hubble and Spitzer, of course, but at the same time, a whole range of people, institutions, and organisations come together to make scientific discoveries like this possible, and I think it's important that we recognise that science is often a highly collaborative and international endeavour.
For example, there are 23 astronomers who co-authored the paper on this galaxy: 11 are from US institutions, 11 from European institutions, and 1 from a Chinese one. Note, I didn't say that they were (necessarily) American, European, and Chinese: in the list of co-authors, there are at least some Europeans working in the US and vice versa.
Also, the Hubble Space Telescope is a collaboration between NASA and ESA, the European Space Agency, albeit with NASA in this instance contributing the majority. There are other space missions including Herschel and Planck which are led by ESA, but in which NASA plays a minority role. Many space missions are collaborative in this way, in essence underpinning the mix of US-based, Europe-based, and other international astronomers who've written this paper.
In more detail, it can get even more complicated when you realise that NASA, ESA, and other space agencies themselves employ astronomers and other space scientists, so in that sense, discoveries can be made by those organisations too.
Speaking of which, it might have been more appropriate to give the links to the original US and European press releases from the Space Telescope Science Institute, NASA, and ESA to get the full story.
Anyway, despite the (important, I believe) pedantry, this is is an interesting discovery:-)
Sorry, you're both correct: to say that we "know" was perhaps too strong a statement on my part. It was just meant as a scientific shorthand for "some smart folks really really think they came from Mars and they have some really strong arguments (and data) to support that claim", as you wrote.
It might have been better to say something like it is strongly believed that, or it is very likely that, or the most likely interpretation is that, or there is a very strong case for, and so on. But it's a pretty common shorthand in science to say "we know", and everybody understanding what is meant by such a statement without delving into the deeper recesses of epistemology.
In answer to the point made that "we were never there", err, where? Mars? No, we, as people, were not; but we, via some pretty capable robots, were. One of the fundamental pieces of evidence that scientists use to justify the claim that we have Mars rocks on Earth is that trapped gases in them have an isotopic ratio that matches that of the Martian atmosphere as measured by Viking, not that of Earth.
Absolutely, positively? No, science doesn't deal in those statements. Based on all available evidence, so likely that it's perfectly reasonable to effectively rule out nuttier alternatives? Yes.
Well, in principle the paper is a fairly simple series of mathematical equations which you could actually work out on the back of an envelope. The devil though is in the details, namely the numerical parameters input to those equations. While many of those are straightforward and well-known, some may enter that category of WAGs (wild-assed guesses), and it's quite possible that the equations are particularly sensitive to (some of) those. That's why it's worth reading, to try and figure out where the issues may be.
As for the testability side, you're right, of course: very hard. But again, since we know of Martian rocks having made it to Earth via this mechanism, we can at least start to use some hard numbers based on that to try and constrain the likelihood of the Earth rocks having made it to other planets / moons.
I've made a quick scan of the underlying academic article by Hara et al., along with one of my colleagues in a meeting here, who is closely involved in the issue of planetary protection (i.e. making sure that our spacecraft don't "pollute" the solar system bodies they fly to and land on).
Of course, this is a known issue in general: after all, there are meteorites on Earth which we know came from Mars, so the converse is obviously possible. But extending this to moons of Jupiter, Kuiper Belt objects, and even exoplanetary systems, and finding that a significant number of Earth rocks may have been dumped there is interesting. So, the article is worth a more careful read.
However, my antennae were sent into a state of high agitation when I saw that the article has been posted on the arXiV following its having been accepted to the infamous Journal of Cosmology. We've discussed that here before: I invite you to view the journal website (easily found by googling) and decide for yourselves how reputable it is.
Which raises the question of why Hara et al. chose to publish there. That I can't answer, obviously, but will keep it firmly in mind as I read the paper in more detail.
The squirrels in question aren't the grey or red ones that run around in trees; they're ground squirrels, so things like marmots and prairie dogs at the big end and chipmunks at the small end.
I don't think regular grey tree squirrels are from the same genus. And I'm not 100% sure that all ground squirrels do this; the classic example of an infrared light sabre wielding species is the California ground squirrel.
I've long since given up on there being any semblance of proper research done in such articles, particularly when a nod might have to be given to anyone outside the US.
I'm no expert in the history of solar electric ion propulsion systems, but believe that NASA's Deep Space-1 mission in 1998 was (I think) the first to use SEP as its primary post-launch propulsion, as several subsequent NASA missions, including Dawn, as discussed in the article.
However, several European Space Agency missions have also used similar systems, including the ARTEMIS satellite in 2001 to get itself to geostationary orbit, the SMART-1 mission to the Moon (launched 2003, ended in a deliberate crash onto the Moon in 2006), the GOCE gravity-mapping mission, and the BepiColombo mission to Mercury (due for launch in 3 years) will be using one. The Japanese Hayabusa-1 asteroid sample return mission also used one.
Just trying to set the record at least a little straighter...
What can I say? I'm very pleased that Kader Arif had the guts to make his disgust with the ACTA process known so publicly. His actions deserve to be widely recognised outside the tech community as well as within; we should ensure that "regular" media outlets cover this part of the story.
Will his stand bring down the entire shameful edifice that is ACTA? No. Is it an important part of the battle that is being fought and must continue to be fought? Yes.
If you read the article, it's clear that this is intended to be an instrument which includes a very wide-field imager (3cm aperture) and a somewhat higher-spatial resolution (although that's only in a relative sense) channel with a 15cm aperture, both to operate in the optical/near-infrared. This is not about high spatial resolution imaging of the HST/JWST kind.
The aim is to detect the very faint extragalactic background light (EBL), which includes a component due to the integrated light from the first generation of galaxies in the Universe. Since the zodiacal light of the solar system drowns out that light, getting out beyond 5AU and thus beyond most of the asteroids which yield the dust which in turn reflect sunlight / emit their own IR flux, makes your telescope much more sensitive.
I would have said that this is just YAJS or Yet Another JPL Study, of which we've had several appear in these pages of late. If you want studies, I can give you loads of them: doesn't mean they're going to happen. And yet this one involves Chas Beichman and he knows what he's up to. It also very deliberately name checks the ESA JUICE (Jupiter Icy Moons Explorer) mission as a possible carrier for the proposed instrument package. OK, JUICE is also just a study at the moment, but within six months time, there's a 1-in-3 chance that it'll win the competition to be ESA's next L-class mission and thus much more "real".
Then again, given that JUICE's destination is the Jupiter system (duh), an EBL experiment would be limited to the cruise stage part en-route to 5AU.
Either way, a title of "NASA Considers Sending Telescope to the Outer Solar System" is pretty misleading: this is a study for an instrument package with a couple of cameras, photometers, and spectrometers which might hitchhike on another satellite; it scarcely qualifies as a "telescope" in the same sense as HST, Spitzer, Herschel, JWST, etc.
While this is certainly interesting technology for future missions, it's worth remembering (as the original NASA article indeed does), that the European Space Agency's Rosetta mission was launched back in 2004 and is already en-route to its rendezvous with comet 67P/Churyumov-Gerasimenko in May 2014. It will "orbit" the comet and observe it as it returns to the inner solar system through 2014 and 2015.
But it will also deploy a small lander called Philae which will use two harpoons and then drills to "dock" with the comet (you don't really land on something with such low surface gravity) and sample the surface material in situ. As the NASA article points out, Philae's harpoon doesn't collect samples itself and, of course, Philae can only land at one location, carefully chosen to be safe through prior close-up observations by the main Rosetta spacecraft. But still, this is actually going to be done real soon now...
Rosetta is currently in hibernation out several astronomical units from the Sun on a trajectory that'll have it meet up with the comet. There's insufficient sunlight out there to power the whole spacecraft, but enough for an alarm clock that should (!) go off in January 2014 when it's close enough to both Sun and comet to begin full operations.
So, looking forward to an exciting ride in 2014-2015, ringside seat right alongside a comet as it heats up and sheds material...
Indeed; the original article doesn't properly reflect that this is JPL wishing for a pony.
Until the beginning of this year, NASA and ESA were working on a joint mission called EJSM (Europa Jupiter System Mission), incorporating a Jupiter Europa Orbiter (JEO) from NASA and a Jupiter Ganymede Orbiter (JGO) from ESA. That derived from an earlier joint mission concept called Laplace which was proposed to ESA's Cosmic Vision call in 2007 as a Large (L) mission. EJSM would have launched (on two separate rockets) no earlier than 2020.
Also in the ESA L-mission competition at the start of 2011 were an X-ray astrophysics observatory (IXO, joint with NASA and JAXA) and a gravitational wave observatory (LISA, joint with NASA).
Then earlier this year, the US Planetary Decadal survey placed Mars exploration at the top of its priority list and everyone recognised that under the current intense budget pressures, big things like JEO lower down the list simply weren't going to happen. Similarly, IXO and LISA had not been top of the equivalent Astrophysics Decadal in late 2010, so they were dead men walking as joint missions too.
ESA has since then reformulated all three of these L-missions as European-only or European-led missions on a smaller scale: in this, JGO has become JUICE (Jupiter Icy Moons Explorer), which would (as the previous poster said) incorporate several Europa flybys prior to the core Ganymede orbiting phase. In passing, the reason Europe isn't going to orbit Europa is mostly down to a lack of (very) rad-hard technology: Europa's a nasty place to spend much time. That said, some minor US collaboration is likely on some of the instrumentation.
The decision on which of the three new L-missions will likely be implemented (pending further technical study) will be taken in spring 2012 by ESA and its advisory bodies. If selected, JUICE would have a launch date around 2022, arriving at Jupiter some 8 years later, following a number of inner solar system gravity assists. All of which makes me sceptical that (a) NASA will go this alone on a double-header mission to Europa and (b) a launch by 2020 is plausible in the current environment.
AEHF is a system of four satellites, I think, not just one, but nevertheless, I completely agree with what you're saying re: JWST. It's crazy.
Interestingly, AEHF is a military communications system with data rates up to 8Mbit/s from an orbit of 22,000 miles, while JWST has a data rate in excess of 10Mbit/s from L2, i.e. just under a million miles. The comparison is completely specious, I realise (just think about the size of the comms antennae involved, uplink vs downlink, and so on), but amuses me nonetheless:-)
There's some confusion here. The raw image resolution provided by Gaia's mirrors is one thing and your estimate of 0.08 arcsec may be appropriate there.
On the other hand, Gaia's real job is to measure the position of stars very accurately, and that it can do down to a few microarcseconds: it doesn't resolve the stars, of course, but provides extremely accurate positions for them. By doing this repeatedly over several years, it can then see objects move by very small distances.
Ten microarcseconds at the distance the Moon is about 2 centimetres, so to be more accurate, Gaia could measure a movement as small as the width of a human thumb at the distance to the Moon.
Not really; these are very specialised custom CCDs made for Gaia alone, to its specific requirements. Because of this, they're a very long lead item and need to be tested rigorously, which means that they needed to be done early. That said, most of the parts of Gaia are ready by now, and the remaining time before launch will be needed for integration and testing of the whole system.
While you're right about the rapid pace of detector development in the commercial sector, those are very different beasts to the ones needed for most scientific applications. For one thing, we almost exclusively use "black-and-white" detectors, i.e. which can image a single colour or single band at a time through a filter: we need this to ensure the highest sensitivity to faint sources. We can then make colour pictures later by superimposing images taken in several different bands. We also generally use very long exposures, so we need detectors which work at very low temperatures to avoid dark current noise. Finally, we can usually tolerate slightly imperfect detectors in terms of dead pixels, because we usually take a series of dithered images and can fill in the bad pixels later. On the other hand, we really care about low read noise.
Commercial detectors these days usually take colour pictures straight off, by having clusters of RGB pixels on chip. Cosmetic quality is at a premium, but dark current noise is less of an issue. Finally, they usually run warm, not at cryogenic temperatures. Many commercial imaging sensors are in fact CMOS devices now, whereas CCDs still pretty much rule the roost for optical imaging in astronomy. That said, I was approached at this week's UK Space Conference in Warwick by representatives from e2v, the suppliers of Gaia's CCDs, wanting to talk to me about scientific uses of their CMOS line:-)
To avoid any confusion, we have finished the assembly of the focal plane assembly (i.e. those 106 large CCDs), but not the full-up satellite itself. That still has a way to go, with launch likely at the end of 2012 or early 2013. But it's nevertheless a great achievement to have the huge detector array done and is a real milestone for us.
Also, Gaia isn't taking pretty pictures of the sky per se: via repeated scans over the sky, it's going to provide extremely accurate positions and velocities for about one billion stars in the Milky Way, allowing us to trace their motions back (and forward) in time, and thus understand how the Milky Way was put together in the first place. It does much, much more than that, so if you're interested, I suggest you follow the link in the original submission for more.
(DIsclosure: I work for ESA and am close to the project)
Well, while I'm certainly of the opinion that the scientific content is highly dubious, it's not necessarily the case that it's a scam per se. That is, I don't think it's a money-raising scheme, fleecing unwitting cranks by deluding them that they're publishing in a reputable journal. I rather think that they all know what they're doing and are doing it willingly, namely that they're a bunch of iconoclasts who've decided to club together to promote their decidedly non-mainstream ideas. I imagine the money involved just covers some minimal costs of running the website etc. No-one's getting rich off this.
After all, the editor-in-chief, Rudy Schild, is a staff astronomer at the Harvard Center for Astrophysics, a completely unimpeachable organisation, and has published many perfectly serious astrophysics papers over the years (although that doesn't necessarily vouch for some of his latter-day publications). Similarly, I imagine that many of the other authors publishing in this "journal" are legitimate scientists of various kinds, but who've decided to take a position against some of the mainstream views of modern cosmology, including the Big Bang.
Of course, being a scientist doesn't automatically make you right and reading through some of the papers on the site, you do have to have to wonder whether they've approached their studies with such open minds that their brains have fallen out.
[p.s. For what it's worth, I also posted the original "Not exactly a mainstream journal" entry, but had forgotten to log in when I did so]
It may well be physically in France, I wouldn't call it French per se. The I in the name most assuredly stands for International, with technical and financial input from around the world (China, the EU, India, Japan, Korea, Russia, and the USA, in alphabetical order).
It's a project we all may ultimately depend on as a civilisation, so the International part is important.
To be honest, I don't hold/. to extraordinarily high standards, but this is so deeply wrong, I feel compelled to register my objections.
This is so obviously a crank book with a commissioned hagiographical review, I don't even begin to understand how it made its way onto the front page.
As a professional physicist, I've seen any number of these sorts of things and they're all complete rubbish. For a tech-related site, I would have expected better. Waaaaay better.
Probably a bit late now for anyone to notice, but let me add a comment here as one of the people that made the Planck image.
The actual full resolution Planck data are far better than the WMAP data, but we have only been able to release a deliberately degraded version of the Planck data at this time. Indeed, we pretty decided to degrade it to WMAP resolution precisely because those data are already in the public domain.
Why? Because the scientists who spent more than a decade designing and building the Planck instruments have legal first rights to the data, and they're presently working very hard at extracting the very faint Cosmic Microwave Background signal from underneath the much brighter foreground galactic emission. This is extremely hard work and will take quite some time yet.
At the same time, we all fully understand the need to show the tax-paying public something from the mission. But we have to be extremely cautious about releasing the full-res data at this point, as some independent people will run a quick and dirty analysis on the data and publish prematurely, claiming discovery rights on something they (or their government finding agencies) never actually spent any time or money on.
Paranoia? Exactly this did happen with the much more limited piece of full-res Planck data we released last year, and we're not about to repeat the mistake.
Please be patient: we will (and are legally committed to doing so!) release the full-res data in the future, once the involved scientists have done their work. I promise that it'll be spectacular...
I'm 100% with your first and last choices. As far as I know, Discovery is already allocated to the NASM Udvar-Hazy Annex at Dulles, presumably to replace Enterprise (which could then be moved elsewhere). KSC is a complete no-brainer, IMHO: one of them must be there, where they spent so very much of their lives. I had a VIP tour through the Orbiter Processing Facility a few weeks ago and was almost in tears when I got to see Endeavour at extremely close quarters (and to actually touch it), thinking that this will all be over soon. End of an era.
As for the third, well, Houston sounds like a very good idea for the reasons you've cited, but I've not visited its space museum to know how good it is and how much of a tourist draw it is.
Errr, morally off the rails. As if that wasn't obvious. Corrupt and propagandistic dictatorships can achieve economic and industrial miracles for their own people, I fully accept that. But I do not accept the cost at which it comes, particularly to those who have been chosen as scapegoats against which to rally support.
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I have had custom silicone moulds for my earphones for almost 10 years and it was one of the best investments I've ever made. The earphones are Etymotic ER4P's and the moulds were made by the Dutch company, Elacin, following the traditional route, i.e. having deep canal impressions made by an audiologist. Elacin work closely with Etymotic, so made moulds to specifically fit their earphones: while I don't see this particular service offered on their website anymore, my experience with them was that they're happy to talk to customers and do what's necessary.
The fit is of these moulds is perfect, the external sound suppression impressive, and the internal sound spectacular, thanks of course to the ER4P's. Together, this means I can listen to and enjoy music at low volumes, and for people around me, they hear absolutely no spillover.
Sure, the combined cost was daunting at the time: somewhere around €600. Ouch. But amortised out over 10 years already and potentially many years to come, it has been well worthwhile for the quality of the sound and the sealing off of the outside world when desired. Living in Holland with all its off-road, dedicated cycling paths, I can even make good use of them on my daily commute.
If I had one complaint about them, it'd be the way that the piezo drivers of the Ety's protrude, making it impossible to place your ear on a pillow with the earphones in. I fly a lot and would like to be able to sleep with the earphones in, suppressing sound and perhaps playing something ambient.Perhaps I should splash out again and get something like high-end Ultimate Ears earphones, where the custom moulds and electronics are integrated into a "flatter" package ... ;-)
I realise that the title of this article was carried over from the CBC article, but could we at least try to remember that it's astronomers that discover things like this high-redshift galaxy, not an administration like NASA in isolation? I don't mean to diminish the absolutely central role played by NASA in both Hubble and Spitzer, of course, but at the same time, a whole range of people, institutions, and organisations come together to make scientific discoveries like this possible, and I think it's important that we recognise that science is often a highly collaborative and international endeavour.
For example, there are 23 astronomers who co-authored the paper on this galaxy: 11 are from US institutions, 11 from European institutions, and 1 from a Chinese one. Note, I didn't say that they were (necessarily) American, European, and Chinese: in the list of co-authors, there are at least some Europeans working in the US and vice versa.
Also, the Hubble Space Telescope is a collaboration between NASA and ESA, the European Space Agency, albeit with NASA in this instance contributing the majority. There are other space missions including Herschel and Planck which are led by ESA, but in which NASA plays a minority role. Many space missions are collaborative in this way, in essence underpinning the mix of US-based, Europe-based, and other international astronomers who've written this paper.
In more detail, it can get even more complicated when you realise that NASA, ESA, and other space agencies themselves employ astronomers and other space scientists, so in that sense, discoveries can be made by those organisations too.
Speaking of which, it might have been more appropriate to give the links to the original US and European press releases from the Space Telescope Science Institute, NASA, and ESA to get the full story.
Anyway, despite the (important, I believe) pedantry, this is is an interesting discovery :-)
Sorry, you're both correct: to say that we "know" was perhaps too strong a statement on my part. It was just meant as a scientific shorthand for "some smart folks really really think they came from Mars and they have some really strong arguments (and data) to support that claim", as you wrote.
It might have been better to say something like it is strongly believed that, or it is very likely that, or the most likely interpretation is that, or there is a very strong case for, and so on. But it's a pretty common shorthand in science to say "we know", and everybody understanding what is meant by such a statement without delving into the deeper recesses of epistemology.
In answer to the point made that "we were never there", err, where? Mars? No, we, as people, were not; but we, via some pretty capable robots, were. One of the fundamental pieces of evidence that scientists use to justify the claim that we have Mars rocks on Earth is that trapped gases in them have an isotopic ratio that matches that of the Martian atmosphere as measured by Viking, not that of Earth.
Absolutely, positively? No, science doesn't deal in those statements. Based on all available evidence, so likely that it's perfectly reasonable to effectively rule out nuttier alternatives? Yes.
Well, in principle the paper is a fairly simple series of mathematical equations which you could actually work out on the back of an envelope. The devil though is in the details, namely the numerical parameters input to those equations. While many of those are straightforward and well-known, some may enter that category of WAGs (wild-assed guesses), and it's quite possible that the equations are particularly sensitive to (some of) those. That's why it's worth reading, to try and figure out where the issues may be.
As for the testability side, you're right, of course: very hard. But again, since we know of Martian rocks having made it to Earth via this mechanism, we can at least start to use some hard numbers based on that to try and constrain the likelihood of the Earth rocks having made it to other planets / moons.
I've made a quick scan of the underlying academic article by Hara et al., along with one of my colleagues in a meeting here, who is closely involved in the issue of planetary protection (i.e. making sure that our spacecraft don't "pollute" the solar system bodies they fly to and land on).
Of course, this is a known issue in general: after all, there are meteorites on Earth which we know came from Mars, so the converse is obviously possible. But extending this to moons of Jupiter, Kuiper Belt objects, and even exoplanetary systems, and finding that a significant number of Earth rocks may have been dumped there is interesting. So, the article is worth a more careful read.
However, my antennae were sent into a state of high agitation when I saw that the article has been posted on the arXiV following its having been accepted to the infamous Journal of Cosmology. We've discussed that here before: I invite you to view the journal website (easily found by googling) and decide for yourselves how reputable it is.
Which raises the question of why Hara et al. chose to publish there. That I can't answer, obviously, but will keep it firmly in mind as I read the paper in more detail.
The squirrels in question aren't the grey or red ones that run around in trees; they're ground squirrels, so things like marmots and prairie dogs at the big end and chipmunks at the small end.
I don't think regular grey tree squirrels are from the same genus. And I'm not 100% sure that all ground squirrels do this; the classic example of an infrared light sabre wielding species is the California ground squirrel.
Bugger: sorry, forgot to log in before posting the previous comment: it was from me, honest ... :-)
I've long since given up on there being any semblance of proper research done in such articles, particularly when a nod might have to be given to anyone outside the US.
I'm no expert in the history of solar electric ion propulsion systems, but believe that NASA's Deep Space-1 mission in 1998 was (I think) the first to use SEP as its primary post-launch propulsion, as several subsequent NASA missions, including Dawn, as discussed in the article.
However, several European Space Agency missions have also used similar systems, including the ARTEMIS satellite in 2001 to get itself to geostationary orbit, the SMART-1 mission to the Moon (launched 2003, ended in a deliberate crash onto the Moon in 2006), the GOCE gravity-mapping mission, and the BepiColombo mission to Mercury (due for launch in 3 years) will be using one. The Japanese Hayabusa-1 asteroid sample return mission also used one.
Just trying to set the record at least a little straighter ...
What can I say? I'm very pleased that Kader Arif had the guts to make his disgust with the ACTA process known so publicly. His actions deserve to be widely recognised outside the tech community as well as within; we should ensure that "regular" media outlets cover this part of the story.
Will his stand bring down the entire shameful edifice that is ACTA? No. Is it an important part of the battle that is being fought and must continue to be fought? Yes.
If you read the article, it's clear that this is intended to be an instrument which includes a very wide-field imager (3cm aperture) and a somewhat higher-spatial resolution (although that's only in a relative sense) channel with a 15cm aperture, both to operate in the optical/near-infrared. This is not about high spatial resolution imaging of the HST/JWST kind.
The aim is to detect the very faint extragalactic background light (EBL), which includes a component due to the integrated light from the first generation of galaxies in the Universe. Since the zodiacal light of the solar system drowns out that light, getting out beyond 5AU and thus beyond most of the asteroids which yield the dust which in turn reflect sunlight / emit their own IR flux, makes your telescope much more sensitive.
I would have said that this is just YAJS or Yet Another JPL Study, of which we've had several appear in these pages of late. If you want studies, I can give you loads of them: doesn't mean they're going to happen. And yet this one involves Chas Beichman and he knows what he's up to. It also very deliberately name checks the ESA JUICE (Jupiter Icy Moons Explorer) mission as a possible carrier for the proposed instrument package. OK, JUICE is also just a study at the moment, but within six months time, there's a 1-in-3 chance that it'll win the competition to be ESA's next L-class mission and thus much more "real".
Then again, given that JUICE's destination is the Jupiter system (duh), an EBL experiment would be limited to the cruise stage part en-route to 5AU.
Either way, a title of "NASA Considers Sending Telescope to the Outer Solar System" is pretty misleading: this is a study for an instrument package with a couple of cameras, photometers, and spectrometers which might hitchhike on another satellite; it scarcely qualifies as a "telescope" in the same sense as HST, Spitzer, Herschel, JWST, etc.
While this is certainly interesting technology for future missions, it's worth remembering (as the original NASA article indeed does), that the European Space Agency's Rosetta mission was launched back in 2004 and is already en-route to its rendezvous with comet 67P/Churyumov-Gerasimenko in May 2014. It will "orbit" the comet and observe it as it returns to the inner solar system through 2014 and 2015.
But it will also deploy a small lander called Philae which will use two harpoons and then drills to "dock" with the comet (you don't really land on something with such low surface gravity) and sample the surface material in situ. As the NASA article points out, Philae's harpoon doesn't collect samples itself and, of course, Philae can only land at one location, carefully chosen to be safe through prior close-up observations by the main Rosetta spacecraft. But still, this is actually going to be done real soon now ...
Rosetta is currently in hibernation out several astronomical units from the Sun on a trajectory that'll have it meet up with the comet. There's insufficient sunlight out there to power the whole spacecraft, but enough for an alarm clock that should (!) go off in January 2014 when it's close enough to both Sun and comet to begin full operations.
So, looking forward to an exciting ride in 2014-2015, ringside seat right alongside a comet as it heats up and sheds material ...
Indeed; the original article doesn't properly reflect that this is JPL wishing for a pony.
Until the beginning of this year, NASA and ESA were working on a joint mission called EJSM (Europa Jupiter System Mission), incorporating a Jupiter Europa Orbiter (JEO) from NASA and a Jupiter Ganymede Orbiter (JGO) from ESA. That derived from an earlier joint mission concept called Laplace which was proposed to ESA's Cosmic Vision call in 2007 as a Large (L) mission. EJSM would have launched (on two separate rockets) no earlier than 2020.
Also in the ESA L-mission competition at the start of 2011 were an X-ray astrophysics observatory (IXO, joint with NASA and JAXA) and a gravitational wave observatory (LISA, joint with NASA).
Then earlier this year, the US Planetary Decadal survey placed Mars exploration at the top of its priority list and everyone recognised that under the current intense budget pressures, big things like JEO lower down the list simply weren't going to happen. Similarly, IXO and LISA had not been top of the equivalent Astrophysics Decadal in late 2010, so they were dead men walking as joint missions too.
ESA has since then reformulated all three of these L-missions as European-only or European-led missions on a smaller scale: in this, JGO has become JUICE (Jupiter Icy Moons Explorer), which would (as the previous poster said) incorporate several Europa flybys prior to the core Ganymede orbiting phase. In passing, the reason Europe isn't going to orbit Europa is mostly down to a lack of (very) rad-hard technology: Europa's a nasty place to spend much time. That said, some minor US collaboration is likely on some of the instrumentation.
The decision on which of the three new L-missions will likely be implemented (pending further technical study) will be taken in spring 2012 by ESA and its advisory bodies. If selected, JUICE would have a launch date around 2022, arriving at Jupiter some 8 years later, following a number of inner solar system gravity assists. All of which makes me sceptical that (a) NASA will go this alone on a double-header mission to Europa and (b) a launch by 2020 is plausible in the current environment.
I know; that's why I said that my comparison was specious.
I didn't mean for it to be taken seriously; I was just amused by the roughly coincident data rates.
AEHF is a system of four satellites, I think, not just one, but nevertheless, I completely agree with what you're saying re: JWST. It's crazy.
Interestingly, AEHF is a military communications system with data rates up to 8Mbit/s from an orbit of 22,000 miles, while JWST has a data rate in excess of 10Mbit/s from L2, i.e. just under a million miles. The comparison is completely specious, I realise (just think about the size of the comms antennae involved, uplink vs downlink, and so on), but amuses me nonetheless :-)
There's some confusion here. The raw image resolution provided by Gaia's mirrors is one thing and your estimate of 0.08 arcsec may be appropriate there.
On the other hand, Gaia's real job is to measure the position of stars very accurately, and that it can do down to a few microarcseconds: it doesn't resolve the stars, of course, but provides extremely accurate positions for them. By doing this repeatedly over several years, it can then see objects move by very small distances.
Ten microarcseconds at the distance the Moon is about 2 centimetres, so to be more accurate, Gaia could measure a movement as small as the width of a human thumb at the distance to the Moon.
Not really; these are very specialised custom CCDs made for Gaia alone, to its specific requirements. Because of this, they're a very long lead item and need to be tested rigorously, which means that they needed to be done early. That said, most of the parts of Gaia are ready by now, and the remaining time before launch will be needed for integration and testing of the whole system.
While you're right about the rapid pace of detector development in the commercial sector, those are very different beasts to the ones needed for most scientific applications. For one thing, we almost exclusively use "black-and-white" detectors, i.e. which can image a single colour or single band at a time through a filter: we need this to ensure the highest sensitivity to faint sources. We can then make colour pictures later by superimposing images taken in several different bands. We also generally use very long exposures, so we need detectors which work at very low temperatures to avoid dark current noise. Finally, we can usually tolerate slightly imperfect detectors in terms of dead pixels, because we usually take a series of dithered images and can fill in the bad pixels later. On the other hand, we really care about low read noise.
Commercial detectors these days usually take colour pictures straight off, by having clusters of RGB pixels on chip. Cosmetic quality is at a premium, but dark current noise is less of an issue. Finally, they usually run warm, not at cryogenic temperatures. Many commercial imaging sensors are in fact CMOS devices now, whereas CCDs still pretty much rule the roost for optical imaging in astronomy. That said, I was approached at this week's UK Space Conference in Warwick by representatives from e2v, the suppliers of Gaia's CCDs, wanting to talk to me about scientific uses of their CMOS line :-)
Apologies: too many "assembly"'s in the first sentence, but you get my drift, I hope :-)
To avoid any confusion, we have finished the assembly of the focal plane assembly (i.e. those 106 large CCDs), but not the full-up satellite itself. That still has a way to go, with launch likely at the end of 2012 or early 2013. But it's nevertheless a great achievement to have the huge detector array done and is a real milestone for us.
Also, Gaia isn't taking pretty pictures of the sky per se: via repeated scans over the sky, it's going to provide extremely accurate positions and velocities for about one billion stars in the Milky Way, allowing us to trace their motions back (and forward) in time, and thus understand how the Milky Way was put together in the first place. It does much, much more than that, so if you're interested, I suggest you follow the link in the original submission for more.
(DIsclosure: I work for ESA and am close to the project)
You will be greatly missed, Elisabeth.
After all, the editor-in-chief, Rudy Schild, is a staff astronomer at the Harvard Center for Astrophysics, a completely unimpeachable organisation, and has published many perfectly serious astrophysics papers over the years (although that doesn't necessarily vouch for some of his latter-day publications). Similarly, I imagine that many of the other authors publishing in this "journal" are legitimate scientists of various kinds, but who've decided to take a position against some of the mainstream views of modern cosmology, including the Big Bang.
Of course, being a scientist doesn't automatically make you right and reading through some of the papers on the site, you do have to have to wonder whether they've approached their studies with such open minds that their brains have fallen out.
[p.s. For what it's worth, I also posted the original "Not exactly a mainstream journal" entry, but had forgotten to log in when I did so]
It may well be physically in France, I wouldn't call it French per se. The I in the name most assuredly stands for International, with technical and financial input from around the world (China, the EU, India, Japan, Korea, Russia, and the USA, in alphabetical order).
It's a project we all may ultimately depend on as a civilisation, so the International part is important.
To be honest, I don't hold /. to extraordinarily high standards, but this is so deeply wrong, I feel compelled to register my objections.
This is so obviously a crank book with a commissioned hagiographical review, I don't even begin to understand how it made its way onto the front page. As a professional physicist, I've seen any number of these sorts of things and they're all complete rubbish. For a tech-related site, I would have expected better. Waaaaay better.
Good grief.
Probably a bit late now for anyone to notice, but let me add a comment here as one of the people that made the Planck image.
The actual full resolution Planck data are far better than the WMAP data, but we have only been able to release a deliberately degraded version of the Planck data at this time. Indeed, we pretty decided to degrade it to WMAP resolution precisely because those data are already in the public domain.
Why? Because the scientists who spent more than a decade designing and building the Planck instruments have legal first rights to the data, and they're presently working very hard at extracting the very faint Cosmic Microwave Background signal from underneath the much brighter foreground galactic emission. This is extremely hard work and will take quite some time yet.
At the same time, we all fully understand the need to show the tax-paying public something from the mission. But we have to be extremely cautious about releasing the full-res data at this point, as some independent people will run a quick and dirty analysis on the data and publish prematurely, claiming discovery rights on something they (or their government finding agencies) never actually spent any time or money on.
Paranoia? Exactly this did happen with the much more limited piece of full-res Planck data we released last year, and we're not about to repeat the mistake.
Please be patient: we will (and are legally committed to doing so!) release the full-res data in the future, once the involved scientists have done their work. I promise that it'll be spectacular ...
I'm 100% with your first and last choices. As far as I know, Discovery is already allocated to the NASM Udvar-Hazy Annex at Dulles, presumably to replace Enterprise (which could then be moved elsewhere). KSC is a complete no-brainer, IMHO: one of them must be there, where they spent so very much of their lives. I had a VIP tour through the Orbiter Processing Facility a few weeks ago and was almost in tears when I got to see Endeavour at extremely close quarters (and to actually touch it), thinking that this will all be over soon. End of an era.
As for the third, well, Houston sounds like a very good idea for the reasons you've cited, but I've not visited its space museum to know how good it is and how much of a tourist draw it is.
New York is a truly bad idea.
Errr, morally off the rails. As if that wasn't obvious. Corrupt and propagandistic dictatorships can achieve economic and industrial miracles for their own people, I fully accept that. But I do not accept the cost at which it comes, particularly to those who have been chosen as scapegoats against which to rally support.