Hubble Directly Images Disc Around a Black Hole

An anonymous reader sends this excerpt from the HST site: "A team of scientists has used the NASA/ESA Hubble Space Telescope to observe a quasar accretion disc — a brightly glowing disc of matter that is slowly being sucked into its galaxy's central black hole. Their study makes use of a novel technique that uses gravitational lensing to give an immense boost to the power of the telescope. The incredible precision of the method has allowed astronomers to directly measure the disc's size and plot the temperature across different parts of the disc."

Comments

We've come a long way...

[msobkow]

We've come a long way since we first gazed at the stars and wondered...

Re:We've come a long way...

[Canazza]

As opposed to what we do now?

Hubble Space Telescope

[ackthpt]

Blowing your mind since 1990

Best damn use of NASA funds, since the Moon landing.

Re:Hubble Space Telescope

[peragrin]

I would say the mars rovers were a better bang for the buck, but hubble is a close second even with all the retrofits.

I still find it a shame that the last shuttle mission wasn't a trip to the hubble to bring it home. just like the shuttle were designed to do.

Re:Hubble Space Telescope

[frosty_tsm]

I would say the mars rovers were a better bang for the buck, but hubble is a close second even with all the retrofits.

I still find it a shame that the last shuttle mission wasn't a trip to the hubble to bring it home. just like the shuttle were designed to do.

Other than for it to go into a museum, what would be the benefit of spending millions of dollars bringing 20-year-old technology back to earth (rather than letting it spend another 10 years in space)? Sure you can say stuff like "to see what the effects of 20 years in 0-gravity were" but we have other examples.

Brilliant

[Bovius]

Using stars between us and the black hole as a lens to magnify the viewing target? That seems like the astronomer's equivalent of a ninja move. Brilliant.

We're sure getting a lot of use out of Hubble. Weren't we planning on decommissioning it at some point in time? I'm glad we didn't.

Re:Brilliant

[EngrBohn]

Alas, we have no way to conduct servicing missions to maintain HST. Sooner or later, it will have to be decommissioned.

Re:Brilliant

[Kjella]

Well, the effect has been known since 1979. It's just that everything lines up very rarely, it's amazingly effective when it works but you can't exactly move the lens so you only get to focus on what's exactly behind it. We are going to need bigger and better telescopes to solve the general case.

Albert Einstein, bad-ass

[93 Escort Wagon]

And to think he figured this stuff out around 100 years ago...

Re:Albert Einstein, bad-ass

[ackthpt]

And to think he figured this stuff out around 100 years ago...

About 8 years ago I was using the Deep Field View for my desktop wallpaper - there's a lot of gravitational lensing going on in there, if you look carefully. Ol' Albert was a pretty sharp one, a little sad he didn't live to see these sorts of images - I'm certain he'd be so stoked that he'd pump his fist and shout, "Yesssss!"

In the spirit of science I'll toast to his memory with a pint when I gets home tonight.

Hubble: White Elephant MY ASS!

[Chas]

Giving the finger to naysayers, budget cutters and luddite schmucks for 20+ years (and going). Not to mention some absolutely MIND-BLOWING interstellar photography.

Definitely not bad for a girl with glasses.

Could this be done from the ground?

[wisebabo]

I'm all for Hubble and am very happy they did the "risky" last servicing mission but I was just wondering, could this be done from the ground?

With ground based scopes around 10m in diameter the light capacity (except on a cloudy day!) would far surpass the Hubble. Do the "artificial" star techniques not work well enough!? Or maybe the dwell time is too long? Or maybe these images are in a part of the spectrum that doesn't go through the atmosphere?

Re:Could this be done from the ground?

[Carnivore]

You're right in all of your suppositions. (Except for cloudy day--It's the cloudy nights you have to watch out for :)

Today's 10m class and tomorrow's 30m class telescopes can do a lot of what Hubble has done, especially when you factor in advanced AO systems like the one that was recently installed on Gemini South (one 50W laser split into 5 beams for correction over a large field). Anything on the ground is cheaper than in space.

Hubble, JWST, Chandra, and the others can see wavelengths that are absorbed by the atmosphere, no matter how high you are.

And integration time is a huge factor. The Ultra Deep Field image was over 1.1 million seconds of exposure. It's just not practical to do exposures like that from the ground.

Re:Could this be done from the ground?

[wierdling]

I process data from the Hubble and also from the ESO Southern Observatory. And that images (and hence data) from the Hubble are still very much clearer than what the ESO SO can take. Not having to look through an ocean of air makes a huge difference.

Re:Could this be done from the ground?

[Anonymous Coward]

Since Hubble was launched, advances in adaptic optics have made it possible to capture images of similar quality from the ground. However, there is a trade-off. The nature of adaptive optics means that they are very good for imaging small regions of the sky. This is great if you want to examine a specific object with pinpoint accuracy. However, adaptive optics isn't good if you want to survey large areas of the sky - a space-based telescope such as Hubble is still the best choice for that kind of work. So it's really a question of what kind of science you want to do. For some sorts of work, ground-based telescopes are the way to go. For others, a space-based telescope allow you to perform work that wouyld take years from the ground in a fraction of the time.

However, keep in mind that adaptive optics didn't become common in astronomy until the late 1990s (although the theory was known since the 1950s).

Also, note that telescopes greater that 8m in diameter need to use a second technology known as Active Optics to correct for tiny deformations in the mirror caused by temperature changes - without this technology it is impossible to build telescopes much wider than 6-7m in diameter. This technology became available in the late 1980s and is the main reason why larger ground-based telescopes are becoming more common now.

So Hubble was launched only a few years before ground-based telescopes started to catch up with some of its capabilities - but it still has a few tricks up its sleeve that they find it hard to match.

Funny Interference Pattern

[Doc Ruby]

Looking at that image, the two main features look like symmetric interference patterns, fairly simple ones. Why not do the Fourier (or other) analysis to recompose the original light signals?

Re:Other uses for space telescopes

[QuasiSteve]

imagine a space telescope that's designed for observing objects inside our solar system. It'd be like putting the moon under a microscope, or exploring Mars and getting detailed survey results without the time and expense of sending a probe there. Is it possible?

Not by traditional means, at least. Essentially, the resolving power of any telescope is limited and the only way to increase it is to use larger lenses. Looks like some articles disagree on the exact size needed for certain features, but google for "telescope flag moon" (minus quotes) for many answers to the question of whether you could see the U.S. flag on the Moon with a telescope, most of which also answer whether Hubble could see it, what you'd need to see it, etc.

Putting telescopes in orbit around the objects of interest still seems the best bet.

If you had a system that didn't care about optics it might fare better.. but then how would you measure things? Extremely fine movements of, say, a laser imager? Not sure how you'd keep the satellite stable enough :)