The post has a ton of misleading information within it, quasars (short of Quasi-stellar object) is a bit of a misnomer. Quasars are associated with Galaxies and the reason some galaxies appear as quasars depends on the activity of their supermassive black hole at the center. When it's very active and eating a lot of mass the galaxy will appear as a quasar, when the feeding of the supermassive black hole shuts down the signature of quasar activity disappears. Quasars are associated with galaxies and do not exist without a galaxy.
The actual article in Wired talks about the new investigations into the physics of matter being accreted by the black hole to explain the rapid shutdown, but the poster erroroneously suggests that this in some way has to do with 'many mini-big bangs,' the article discusses nothing of the sort. In addition, the post mentions that this means that quasars are 'ejected' and not as distant as they appear from their redshift. The redshift of a quasar comes from the galaxy redshift, so even if the supermassive black hole had been ejected, it would still be as distant as the galaxy is. Being ejected from a galaxy will not instantaneously make the black hole substantially closer.
Slashdot should do better to not allow posters to insert their crackpot ideas into the submission of what is actually a really interesting article.
I think the post is confusing the shutdown of the Tevatron at Fermilab with the cancellation of the Superconducting Super Collider. The Super Collider was cancelled in late 1993, which would have been larger than the Large Hadron Collider, comparable to the proposed collider in China. The Tevatron at Fermilab had been running from the 1980's until late 2011 when the project was ended once the LHC ramped up to higher energies.
The funding for NRAO comes from the National Science Foundation, which is funded by the federal government. When an appropriations bill was not passed, NSF did not get any money, so they could not give any money to NRAO to continue operating. The National Science Foundation could not authorize NRAO to continue operating without funding. So, in short, this isn't being done to save money, it's being done because there is no money.
The article also washes over the fact that there are different telescopes for different parts of the radio spectrum. The MWA and LOFAR are the most powerful in the MHz regime, but the VLA is still the most powerful between 1 to 50 GHz, and ALMA is the most powerful from 85 and 700 GHz.
This is a huge error in the Wired article "The telescopes searched for alpha particles emitted by Hydrogen atoms (commonly found in star formation, appearing as a bright red light)." An alpha particle is the nucleus of a Helium atom, so if hydrogen could emit that it would be an incredible feat! However, they really mean H-alpha line emission, a bright emission line that comes from the recombination of a proton and electron and it can be measured out to high redshifts.
They aren't observing fusion since that process takes place deep inside the stars.
While there have been other telescopes that observed in the infrared, JWST will have a mirror 6x larger than the prevous space-based telescopes that operate or have operated at the same wavelengths (0.8 to 24 microns). This means that JWST will have a factor of 6 better resolution than previous telescopes and be incredibly more sensitive due to the larger collecting area. Ground-based telescopes cannot compete with JWST because of the sky brightness in the infrared making sensitive observations very time consuming. The science drivers of JWST are primarily the high-redshift universe, that is galaxies that were formed shortly after the big bang. This is something Hubble cannot do since it is not infrared optimized (the telescope is quite warm compare to JWST's operating temperature) and has too small of an aperture for the resolution needed.
The lack of future Hubble servicing has a lot to do with the retirement of the Space Shuttles, the only platform that can be used to service HST. Hubble will be kept going as long as possible since it is still doing outstanding science. In the 2020s it is hoped to launch an 8m class optical-uv telescope to truly replace Hubble.
The target will not be observed with the array of four telescopes, rather just one of the telescopes will do the observation. Taking data simultaneously with all four telescopes is a tricky procedure and yields data, while extremely useful scienfically, it's very different from the pretty pictures that this contest is after.
FTFA: "LkCa 15 b is the youngest planet ever found, about 5 times younger than the previous record holder," said astronomer Adam Kraus of the University of Hawaii's Institute for Astronomy.
WTF is 5 times younger? Does he mean 1/5 as old? At the moment the planet first started to form, was it infinitely times younger? You'd think a scientist would know better.
Picky picky, do you have anything intelligent to add or are you just going to argue semantics rather than acknowledge good science?
This is actually a very important discovery, the circumstellar disk surrounding the young star has been found to have a deficit of emission ~55 AU in radius. The cause of holes or gaps in proto-planetary disks has been a matter of intense debate in recent years, some people favor planets clearing gaps, others favor emission from the star causing the disk to evaporate. This seems to be clear evidence that planets are actually doing the gap opening and play a key role in the dissipation of disks around stars.
Not all of American's jets have in-seat entertainment. The entire 767 fleet does not have in-seat entertainment, merely the overhead screens. The 777 fleet does have the in-seat screens, but perhaps you would get different options, and your laptop screen is probably nicer to watch something off of than the small ones in the seat.
As for American being a terrible airline, I have to disagree with you. Perhaps they're not a nice as some of the international carriers due to the cut-throat market in the US, but I have been quite happy with my experiences flying them for domestic and international purposes.
The VLA is not being closed, it has been substantially upgraded and is now known as the EVLA, E for expanded. The array being constructed in Chile ALMA the Atacama Large Millimeter Array operates at higher frequencies 88GHz to ~700 GHz whereas the EVLA operates between 74MHz and 50 GHz. They are complementary facilities, in addition, ALMA is a multinational project, Europe, Japan, and the US. Arecibo has been under discussion for closure for many years; however, to restore the site to its natural state (as required by contract) would cost much more than keeping it running.
Science is popular; however, progress comes slowly these days and a lot must go on behind the scenes before something of broad interest comes out. The new facilities like the EVLA, ALMA, and the Large Hadron Collider are able to make ground breaking discoveries that are difficult to achieve with more limited instrumentation.
I missed a point here, you seemed to be implying using these for optical interferometry. However, we cannot currently digitize an optical signal and current optical interferometers use analog methods to create interference fringes. At radio wavelengths we can simply downconvert the signal so something more manageable and then calculate the antenna-antenna the interference.
You still have to contend with the diffraction limit though, 100% efficiency be damned if you can't resolve anything. Also, CCDs are not as ineffecient as you are purporting them to be; they are as efficient as ~90% at some wavelengths (http://www.astronomy.ohio-state.edu/MDM/MDM4K/qe.jpg); therefore, getting 100% effeciency is not going to increase your signal as significantly as you seem to think.
The above post is almost completely correct. However, even the cheapo equatorial drives should be ok for wide-field astrophotography with a 18-55mm lens. Their poor guiding will only start to show if you attempt to do zoomed shots on specific targets. So as long as you don't care about taking pictures through your telescope then this should be ok.
I would love to install this on my RHEL5 office system, but our IT guy has SE Linux enabled on all the systems. The new firefox throws AVC denials so I guess I'm stuck with older versions.
BEfore we wet our pants in excitement, let's remember:
* The Hubble passed a slew of design reviews too. * Even so, it went up with many, many flaws, including: * Electronics not shielded well enough to handle the South Atlantic Anomaly. * Gyroscopes not qualified for the temperature cycles and SAA. * Solar panels that oilcan buckle when going from sunlight to shade. * Solar panel mount that does not go through the center of mass of the scope, so oilcan buckling causes the whole thing to oscillate. * Unbalanced and uncushioned light cap that likewise shakes the whole thing when it's operated.
Although the new scope will have been checked against that list of problems, without major overhaul of the management structure, it's likely the same thing will happen this time.
Granted Hubble had many problems when it launched mainly because it was one of the first and most advanced general purpose observatories launched.
We have had tons of experience building space telescopes over the past 30 years since Hubble was designed and Hubble is the only one that is serviceable by the shuttle.
Just to list all the successful observatories since Hubble:
Infrared Space Observatory (Europe) Chandra X-Ray observatory Spitzer Space Telescope WMAP FUSE Herschel Space Observatory (Mostly Europe) Planck (Europe) Suzaku X-Ray observatory (Japan) and probably a few others I forgot about.
Bottom line, we know a lot about building space telescopes now, the doom and gloom you forecast is probably a bit over the top. Every project has problems, that's why we have brilliant engineers to find solutions.
It is a pity more isn't put into projects like this - I personally feel that we've have learnt so much from Hubbble that it is, at least for the time being, the best option for space exploration. But what wil happen to Hubble? Surely it will retain some functionality into the future?
They'll keep Hubble going as long as they can since its capabilities aren't going to be duplicated by any mission within the next decade. The weak link of the telescope seems to be the gyroscopes, which are used to point the telescope. They'll probably fail before the instruments have completely failed.
OK so their instrument had an upset. That sort of thing happens in space. Why did it take them 5 months to switch over to the redundant string?
It took them 5 months to switch over to the redundant system because they wanted to be sure that they fully understood what happened with the first failure. The problem was that there wasn't software protection for the critical systems. They then had to put preventative measures in place to ensure that it didn't happen to the redundant system; otherwise they would be screwed. The HIFI instrument has some of the most discovery potential and its capabilities cannot be duplicated from earth or and only partly with the SOFIA airborne mission.
In order to take the long exposures necessary an equatorial mount is necessary. As an object moves through the sky the field in an alt-az telescope rotates. Thus, you would have to take short enough exposures to ensure that the rotation doesn't smear the images and then rotate them as you stack them. Also, tracking is a bit more complicated since you have to drive on two axes.
The large alt-az telescopes like Magellan, Gemini, and Keck get around the field rotation problem by having the instruments on a rotator to take out the field rotation.
Also, it takes a decent scope to see detail on saturn, such as a C5. A department store scope would never be able to.
While you might not see color bands, even a cheap telescope will let you see the rings. Heck, Galileo could sort of see the rings and he had optics much worse than a department store telescope!
Just a minor correction. the scientists did use interferometry but it was not "very long baseline interferometry". The "very long" term applies to the telescopes being separated by extreme distances, say over the entire United States as is the case of the VLBA. Also, the VLBA can only function in radio wavelengths because the data can be taken at the individual telescopes an recombined later. With near-infrared interferometry, what the authors of this study were using, requires that the light from each telescope be sent down an optical tube with mirrors and recombined at a central location which constrains the IOTA telescopes to be close together.
IOTA was dismantled a few years ago, geiven that a new optical/near-infrared interferometry was coming online, CHARA http://www.chara.gsu.edu/CHARA/
Everyone seems to be aware of the historic Mount Wilson observatory, but there is also the CHARA array on Mount Wilson. It has 6 ~1m telescopes that are linked together as an interferometer studying evolved stars, binaries, and young stars in the near-infrared at extremely high resolution. A colleague of mine just shipped an instrument to the observatory that was been under construction for the past 3 years. So it's not just history and communications towers, it's also a cutting edge scientific facility. I hope it survives, it would be shame if his new instrument was lost as well as the lost research potential for his Ph.D. students.
Slashdot Mirror
The post has a ton of misleading information within it, quasars (short of Quasi-stellar object) is a bit of a misnomer. Quasars are associated with Galaxies and the reason some galaxies appear as quasars depends on the activity of their supermassive black hole at the center. When it's very active and eating a lot of mass the galaxy will appear as a quasar, when the feeding of the supermassive black hole shuts down the signature of quasar activity disappears. Quasars are associated with galaxies and do not exist without a galaxy.
The actual article in Wired talks about the new investigations into the physics of matter being accreted by the black hole to explain the rapid shutdown, but the poster erroroneously suggests that this in some way has to do with 'many mini-big bangs,' the article discusses nothing of the sort. In addition, the post mentions that this means that quasars are 'ejected' and not as distant as they appear from their redshift. The redshift of a quasar comes from the galaxy redshift, so even if the supermassive black hole had been ejected, it would still be as distant as the galaxy is. Being ejected from a galaxy will not instantaneously make the black hole substantially closer.
Slashdot should do better to not allow posters to insert their crackpot ideas into the submission of what is actually a really interesting article.
I think the post is confusing the shutdown of the Tevatron at Fermilab with the cancellation of the Superconducting Super Collider. The Super Collider was cancelled in late 1993, which would have been larger than the Large Hadron Collider, comparable to the proposed collider in China. The Tevatron at Fermilab had been running from the 1980's until late 2011 when the project was ended once the LHC ramped up to higher energies.
The funding for NRAO comes from the National Science Foundation, which is funded by the federal government. When an appropriations bill was not passed, NSF did not get any money, so they could not give any money to NRAO to continue operating. The National Science Foundation could not authorize NRAO to continue operating without funding. So, in short, this isn't being done to save money, it's being done because there is no money.
The article also washes over the fact that there are different telescopes for different parts of the radio spectrum. The MWA and LOFAR are the most powerful in the MHz regime, but the VLA is still the most powerful between 1 to 50 GHz, and ALMA is the most powerful from 85 and 700 GHz.
This is a huge error in the Wired article "The telescopes searched for alpha particles emitted by Hydrogen atoms (commonly found in star formation, appearing as a bright red light)." An alpha particle is the nucleus of a Helium atom, so if hydrogen could emit that it would be an incredible feat! However, they really mean H-alpha line emission, a bright emission line that comes from the recombination of a proton and electron and it can be measured out to high redshifts.
They aren't observing fusion since that process takes place deep inside the stars.
While there have been other telescopes that observed in the infrared, JWST will have a mirror 6x larger than the prevous space-based telescopes that operate or have operated at the same wavelengths (0.8 to 24 microns). This means that JWST will have a factor of 6 better resolution than previous telescopes and be incredibly more sensitive due to the larger collecting area. Ground-based telescopes cannot compete with JWST because of the sky brightness in the infrared making sensitive observations very time consuming. The science drivers of JWST are primarily the high-redshift universe, that is galaxies that were formed shortly after the big bang. This is something Hubble cannot do since it is not infrared optimized (the telescope is quite warm compare to JWST's operating temperature) and has too small of an aperture for the resolution needed.
The lack of future Hubble servicing has a lot to do with the retirement of the Space Shuttles, the only platform that can be used to service HST. Hubble will be kept going as long as possible since it is still doing outstanding science. In the 2020s it is hoped to launch an 8m class optical-uv telescope to truly replace Hubble.
The target will not be observed with the array of four telescopes, rather just one of the telescopes will do the observation. Taking data simultaneously with all four telescopes is a tricky procedure and yields data, while extremely useful scienfically, it's very different from the pretty pictures that this contest is after.
FTFA: "LkCa 15 b is the youngest planet ever found, about 5 times younger than the previous record holder," said astronomer Adam Kraus of the University of Hawaii's Institute for Astronomy.
WTF is 5 times younger? Does he mean 1/5 as old? At the moment the planet first started to form, was it infinitely times younger? You'd think a scientist would know better.
Picky picky, do you have anything intelligent to add or are you just going to argue semantics rather than acknowledge good science?
This is actually a very important discovery, the circumstellar disk surrounding the young star has been found to have a deficit of emission ~55 AU in radius. The cause of holes or gaps in proto-planetary disks has been a matter of intense debate in recent years, some people favor planets clearing gaps, others favor emission from the star causing the disk to evaporate. This seems to be clear evidence that planets are actually doing the gap opening and play a key role in the dissipation of disks around stars.
Not all of American's jets have in-seat entertainment. The entire 767 fleet does not have in-seat entertainment, merely the overhead screens. The 777 fleet does have the in-seat screens, but perhaps you would get different options, and your laptop screen is probably nicer to watch something off of than the small ones in the seat.
As for American being a terrible airline, I have to disagree with you. Perhaps they're not a nice as some of the international carriers due to the cut-throat market in the US, but I have been quite happy with my experiences flying them for domestic and international purposes.
The VLA is not being closed, it has been substantially upgraded and is now known as the EVLA, E for expanded. The array being constructed in Chile ALMA the Atacama Large Millimeter Array operates at higher frequencies 88GHz to ~700 GHz whereas the EVLA operates between 74MHz and 50 GHz. They are complementary facilities, in addition, ALMA is a multinational project, Europe, Japan, and the US. Arecibo has been under discussion for closure for many years; however, to restore the site to its natural state (as required by contract) would cost much more than keeping it running.
Science is popular; however, progress comes slowly these days and a lot must go on behind the scenes before something of broad interest comes out. The new facilities like the EVLA, ALMA, and the Large Hadron Collider are able to make ground breaking discoveries that are difficult to achieve with more limited instrumentation.
I missed a point here, you seemed to be implying using these for optical interferometry. However, we cannot currently digitize an optical signal and current optical interferometers use analog methods to create interference fringes. At radio wavelengths we can simply downconvert the signal so something more manageable and then calculate the antenna-antenna the interference.
You still have to contend with the diffraction limit though, 100% efficiency be damned if you can't resolve anything. Also, CCDs are not as ineffecient as you are purporting them to be; they are as efficient as ~90% at some wavelengths (http://www.astronomy.ohio-state.edu/MDM/MDM4K/qe.jpg); therefore, getting 100% effeciency is not going to increase your signal as significantly as you seem to think.
The site's dead Jim.
The US census did use GPS to pinpoint the exact locations of households. So Brazil can't do that much better....
The above post is almost completely correct. However, even the cheapo equatorial drives should be ok for wide-field astrophotography with a 18-55mm lens. Their poor guiding will only start to show if you attempt to do zoomed shots on specific targets. So as long as you don't care about taking pictures through your telescope then this should be ok.
I'm on the 10th floor of my building and we had some pretty decent swaying going on.
I would love to install this on my RHEL5 office system, but our IT guy has SE Linux enabled on all the systems. The new firefox throws AVC denials so I guess I'm stuck with older versions.
and we don't have root access.
An actual Spitzer image of L1448 is here: http://www.astro.lsa.umich.edu/~jjtobin/images/L1448.jpg and the preprint of the Astrophysical Journal paper is located here: http://arxiv.org/abs/1004.2443
BEfore we wet our pants in excitement, let's remember:
* The Hubble passed a slew of design reviews too.
* Even so, it went up with many, many flaws, including:
* Electronics not shielded well enough to handle the South Atlantic Anomaly.
* Gyroscopes not qualified for the temperature cycles and SAA.
* Solar panels that oilcan buckle when going from sunlight to shade.
* Solar panel mount that does not go through the center of mass of the scope, so oilcan buckling causes the whole thing to oscillate.
* Unbalanced and uncushioned light cap that likewise shakes the whole thing when it's operated.
Although the new scope will have been checked against that list of problems, without major overhaul of the management structure, it's likely the same thing will happen this time.
Granted Hubble had many problems when it launched mainly because it was one of the first and most advanced general purpose observatories launched.
We have had tons of experience building space telescopes over the past 30 years since Hubble was designed and Hubble is the only one that is serviceable by the shuttle.
Just to list all the successful observatories since Hubble:
Infrared Space Observatory (Europe)
Chandra X-Ray observatory
Spitzer Space Telescope
WMAP
FUSE
Herschel Space Observatory (Mostly Europe)
Planck (Europe)
Suzaku X-Ray observatory (Japan)
and probably a few others I forgot about.
Bottom line, we know a lot about building space telescopes now, the doom and gloom you forecast is probably a bit over the top. Every project has problems, that's why we have brilliant engineers to find solutions.
It is a pity more isn't put into projects like this - I personally feel that we've have learnt so much from Hubbble that it is, at least for the time being, the best option for space exploration. But what wil happen to Hubble? Surely it will retain some functionality into the future?
They'll keep Hubble going as long as they can since its capabilities aren't going to be duplicated by any mission within the next decade. The weak link of the telescope seems to be the gyroscopes, which are used to point the telescope. They'll probably fail before the instruments have completely failed.
OK so their instrument had an upset. That sort of thing happens in space. Why did it take them 5 months to switch over to the redundant string?
It took them 5 months to switch over to the redundant system because they wanted to be sure that they fully understood what happened with the first failure. The problem was that there wasn't software protection for the critical systems.
They then had to put preventative measures in place to ensure that it didn't happen to the redundant system; otherwise they would be screwed. The HIFI instrument has some of the most discovery potential and its capabilities cannot be duplicated from earth or and only partly with the SOFIA airborne mission.
In order to take the long exposures necessary an equatorial mount is necessary. As an object moves through the sky the field in an alt-az telescope rotates. Thus, you would have to take short enough exposures to ensure that the rotation doesn't smear the images and then rotate them as you stack them. Also, tracking is a bit more complicated since you have to drive on two axes.
The large alt-az telescopes like Magellan, Gemini, and Keck get around the field rotation problem by having the instruments on a rotator to take out the field rotation.
That was months ago.
Also, it takes a decent scope to see detail on saturn, such as a C5. A department store scope would never be able to.
While you might not see color bands, even a cheap telescope will let you see the rings. Heck, Galileo could sort of see the rings and he had optics much worse than a department store telescope!
Just a minor correction. the scientists did use interferometry but it was not "very long baseline interferometry". The "very long" term applies to the telescopes being separated by extreme distances, say over the entire United States as is the case of the VLBA. Also, the VLBA can only function in radio wavelengths because the data can be taken at the individual telescopes an recombined later. With near-infrared interferometry, what the authors of this study were using, requires that the light from each telescope be sent down an optical tube with mirrors and recombined at a central location which constrains the IOTA telescopes to be close together.
IOTA was dismantled a few years ago, geiven that a new optical/near-infrared interferometry was coming online, CHARA http://www.chara.gsu.edu/CHARA/
Everyone seems to be aware of the historic Mount Wilson observatory, but there is also the CHARA array on Mount Wilson. It has 6 ~1m telescopes that are linked together as an interferometer studying evolved stars, binaries, and young stars in the near-infrared at extremely high resolution. A colleague of mine just shipped an instrument to the observatory that was been under construction for the past 3 years. So it's not just history and communications towers, it's also a cutting edge scientific facility. I hope it survives, it would be shame if his new instrument was lost as well as the lost research potential for his Ph.D. students.