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Under the "Full WFPC2 Mosaic" Heading

Visit the Hubble Heritage Project for a nice picture of Hoag's Object, a beautifull looking ring galaxy (article rejected).

Here's a picture

If any of you had read the explanation on the excellent APOD site, you'd have seen that this thing had already been found in 1985 by Arturo Gomez. This is hust a new Hubble picture of it.

Unfortunately, nott all the bugs have been fixed. I guess that's what you get for not waiting for 1.0.

Because of the huge cost involved in such a project and the increasing risk of orbital debris the telescope will be sheathed in a special alloyed sleeve. The sleeve itself is so massive that it is estimated it will take 3 shuttle flights to lift its segments. Detractors of the project say that while the sleeve does provide excellent protection that fact is more than offset by decreased mobility by making the craft ungainly and impractical to manoeuvre. Another concern is that the huge size of the telescope will interfere with the viewing instrumentation on other nearby space instruments.

However project director Harold Mann responded to the criticisms by saying "Sure my SUV blocks other's view, has terrible fuel efficiency, and handles like shit, but hey if there's a collision it'll be the other guy who gets creamed, especially if it's one of those dinky Japanese models, and in America that's how we like it."

I would have thought that a bigger space based telescope would be better.

One is being planned. However, there's absolutely no way you're going to put a mirror that big in space. So if you care more about number of photons and less about resolution (for example, if you're taking spectra of distant point sources like quasars or planets), it's better (and cheaper!) to do it from the ground.

[TMB]

Just for fun, here are the gory details (see page 3).

Here's the Hubble homepage and here is the original version at few defferent sizes, formats, and borders.

This big enough? :) (got from here)

This big enough? :) (got from here)

all Lem's books are about people... That is probably because you are more people-oriented yourself. I think I liked the mysterious structures because that kind of thing, and its real-life counterparts such as this speak to me more than stories about people, although I read classic literature also and like it very much.

Re,
... dying of brain disease in the year 2075 ... because we were too busy looking for space waterslides...

You want the money spent on medical science so you (and everybody else) can live longer. That's fine, except: Why? There is no point in mere continued metabolism without enjoyment or purpose, and a lot of people, including me, believe that learning is an excellent and enjoyable activity and a worthy goal. My life would be poorer without astronomical research and all I do is read about it on space.com. When I had cancer last year, yes, it would have been nice if they could have said "Here, take this, you're cured," but would I swap the Hubble telescope for it? No way. What is life without things like this in it?

You also want the money spent on reforming bad situations in the world, such as poverty and cruelty. Again, a very fine thing. But it is not possible, even if desirable, to focus entirely on reform and repair. There are two reasons:

- It won't work. People with a scientific bent WILL research, artists will create, comedians will perform, etc., even in the most puritanical society and even at the highest cost to themselves.

- It makes for a self-destructive society. Not the individuals, the culture itself. For instance, the French Revolution. "The revolution has no need of scientists," someone said when they cut off Lavoisier's head. Unbalanced (in the literal sense, not meaning deranged) societies don't last, can't last, and don't leave the world perceptibly better after they go.

Other solution: double up on observations. Different recievers can be attached to a telescope. IR, ultra-violet and visible can be observed at the same time.

Not easily: much of the UV window is very strongly absorbed by the atmosphere, so you can't use it from ground-based telescopes anyway and have to use spacecraft. It's also not so easy to observe two wavelengths at once: you need a lot of complicated optics, and you don't want to waste any of those precious photons. In addition, if the wavelengths are very different, you could have very different design requirements on the rest of the telescope.

So why not double up one projects that are located in the same space in the sky.

They'd have to be really close in the sky. It works for some projects where you're looking at a sample of objects in a patch of sky, like the Hubble Deep Field. However, for many instruments on telescopes like the Keck and Subaru, the field of view is less than 30 arcminutes, which is only the angular diameter of the full moon. Also, the instrument and observing mode you use are strongly dependent on exactly what sort of object you are investigating, and how, and may not be suitable for anything else that happens to be in the field of view.

Also, with image enhancement, you can look at a wider section of sky and view multiple objects, while using computers to examen your specific project.

Image processing and general number-crunching are essential to astronomers already, in order to transform raw data into a final image ("data reduction"). I spent the majority of my Ph.D. working on ways to process a particular type of data, so we're already doing what we can. :-)

Essentially, research-class telescopes are all oversubscribed, and so people tend to make whatever optimisations they can already.

The Fast Facts page says what wavelengths are used in this image. H-alpha and N II are both red, so they probably mapped one of those to green.

From what I understand they are as black and white as the stars we normally see. The Stellar Eggs, for example are awesome in appearance but if you took away the false coloring you end up looking at a fuzzy muddle of greys.

From what I understand they are as black and white as the stars we normally see. The Stellar Eggs, for example are awesome in appearance but if you took away the false coloring you end up looking at a fuzzy muddle of greys.

We take one today, we take one next year, they look identical.

Actually, for objects within our galaxy, many of them change visibly on time scales ranging from days to years (and not just brightness). The best example, from the Hubble Telescope, is the Crab Nebula Movie they did a few years ago. Note that the age of the Crab Nebula was originally determined by comparing photographs taken about 10 years apart, measuring the expansion of the nebula, and extrapolating backward to get an approximate year. Then, a check of historical records shows that there was a supernova in that area of the sky in 1054. Another object which has been known for a long time to show changes visible in a normal telescope is Hubble's Variable Nebula (OK, no cool animation).

We take one today, we take one next year, they look identical.

Actually, for objects within our galaxy, many of them change visibly on time scales ranging from days to years (and not just brightness). The best example, from the Hubble Telescope, is the Crab Nebula Movie they did a few years ago. Note that the age of the Crab Nebula was originally determined by comparing photographs taken about 10 years apart, measuring the expansion of the nebula, and extrapolating backward to get an approximate year. Then, a check of historical records shows that there was a supernova in that area of the sky in 1054. Another object which has been known for a long time to show changes visible in a normal telescope is Hubble's Variable Nebula (OK, no cool animation).

NGC 4013 was also the subject of the Hubble Heritage image for March 2001. Here's a ground-based image from the WIYN telescope at Kitt Peak. It's supposed to be visible in a 6-inch telescope. Next clear night I'll take a look.

Even not looking at plank though we still run out of bits before we run out of things.

Some dumb guy* math:
3.0e+3 galaxies in the Hubble deep field
2.0e+9 stars in our galaxy.
4.6e+8 HDF field images are required to coved the sky

some quick math: ~2.7e+21 stars in the Universe. We're already out of 'bits' and we're still talking about some of the largest strucures in the universe, nowhere near the size of the Plank numbers.

*Meaning I'm not astro or quantum physisist or mathmetician.

Still, remember how many galaxies there were in some of the Hubble Photos? Even if the number of inhabitable planets/galaxy is low, there are still a lot of galaxies out there.

AFAIK, all "raw" Hubble images have that characteristic missing corner, such as this image of the Large Magellanic Cloud taken in November 1996.

I imagine that most of the Hubble images we've seen are composites of several individual pictures, compensating for the missing piece in each individual picture.

As for the cause of the missing corner, I imagine it could be due to the flaw in the telescope's optics and the subsequent fix. Alternately, it could simply be the way the telescope was designed.

Of course, your explanation is much more interesting. :)

--LF

...

"If you took a spaceship toward the Cone Nebula and you got close enough to see it, it would probably look mostly grey, just as the Orion Nebula does in a telescope. And if you got really close to it, it would get so diffuse you probably wouldn't even be aware that you were at it," says Terence Dickinson, editor of Sky News, Canada's popular astronomy magazine.

This is just plain wrong - I feel duped. Maybe this is a bit of an overreaction, but it is basically scientific fraud, since the images are largely presented as depicting the actual appearance by eye. There is nothing wrong with using visual colors to depict non-visual phenomena, such as gamma rays, but it would be nice if this was clearly described. NASA barely labels the images as pseudocolored on their own site and not at all on the main page, so you can't expect the popular press to get this right.

...

"If you took a spaceship toward the Cone Nebula and you got close enough to see it, it would probably look mostly grey, just as the Orion Nebula does in a telescope. And if you got really close to it, it would get so diffuse you probably wouldn't even be aware that you were at it," says Terence Dickinson, editor of Sky News, Canada's popular astronomy magazine.

This is just plain wrong - I feel duped. Maybe this is a bit of an overreaction, but it is basically scientific fraud, since the images are largely presented as depicting the actual appearance by eye. There is nothing wrong with using visual colors to depict non-visual phenomena, such as gamma rays, but it would be nice if this was clearly described. NASA barely labels the images as pseudocolored on their own site and not at all on the main page, so you can't expect the popular press to get this right.

Common Lisp!

You can find some of the details in this paper: COSI: Adding Constraints to the Object-Oriented Paradigm.

Cool stuff!!

This will get us by until the Hubble Heritage Site gets ahold of them or the main site becomes un-/.ed.

The official site to view all of the photos is slashdotted, but for once, we didn't do it.

Make sure you click the introduction link to see the dim stars in context (globular cluster).

Message to stsci.edu:
You disappoint me greatly. The ascii character for an apostrophe is 39, and the ascii character for a double-quote is 34. Your press release contains some out of range ascii values (>= 128) for these characters. Using graphically similar but semantically incorrect characters lowers your prestigious institute to the 31337 H4X0R level.

Make sure you click the introduction link to see the dim stars in context (globular cluster).

Message to stsci.edu:
You disappoint me greatly. The ascii character for an apostrophe is 39, and the ascii character for a double-quote is 34. Your press release contains some out of range ascii values (>= 128) for these characters. Using graphically similar but semantically incorrect characters lowers your prestigious institute to the 31337 H4X0R level.

Posted on the Hubble site 7 days ago when this was news.

"We do, however, have good evidence for the existence of black holes, ..."

Could you please explain us this evidence ?

I don't see any evidence. We only know that current phisic theories predicts the existense of black holes. But we can not create a tiny blackhole in laboratories. And we never saw a blackhole. The photographs we have from HST (like this one), only shows a huge concentration of matter. This is not necessary a black hole.

To believe in the existense of black holes is like to believe in god. Only faith (in current theories) can make us believe in them.

I personally think this proposal of the existense of a "gravastar" substance, is as weird as black holes. But it's normal to create "patch" theories when the main theory has problems. This will happen until we have enough data for a new Einstein to discover a completely new universal theory.

A little sour grapes, perhaps? Don't become bitter, use the energy to bolster your proposal writting skills.

Its amazing that anyone is surprised by the "discovery" of planets around other stars.

Direct obersrervation of these bodies is interesting and exiting, but only because we are finally getting to see directly what most intelligent people already knew was there with absolute certainty, and not because its actually sometheing unexpected.

It would be utterly incredible if there were NO planetary bodies orbiting other stars; now THAT would be a scoop.

The fact that they are finding them so quickly is merely a funciton of having better equipment. You would expect to find more planets with better telescopes, and when they finally put a very big telescope on the dark side of the moon, or launch some other new excellent device, all the smaller bodies will suddely resolve out of the glare.

What I find truely beautiful is the range of unimagined objects that the hubble keeps uncovering week upon week. Like this stuff.

Actually, I think ESO's is a clear winner.
Compare ESO's version (largest is 4.6MB JPEG @ 1951x2366)
and
any on Hubble's page (wide @ 800x813, closeup @ 1000x800).

NOAO has better images than Hubble's too, but they're also wide angle (but still really nice)...
Hubble's MPEG movie animation is very cool though.

The Hubble Space Telescope imaged it last year. They ran an internet poll to pick a target for the Hubble to observe, and the Horsehead won (Cowboy Neal was second, maybe). The Hubble Heritage Project published the result (it's a composite with some ground-based images filling in the edges) and it is better than the VLT picture, IMHO. You can see it here , along with lots of information about how it was made, and high-res versions.

--Seen

Uh, no. GL 229B was discovered by T. Nakajima and a group at Caltech. Check out this link

As you can read, as far as 1995, the Hubble Space Telescope imaged a brown dwarf orbiting a brown dwarf on Gliese 229B. Indeed, some of the US media call it "the first discovered brown-dwarf" although the discoverer was Rafael Rebolo et al at the Instituto de Astrofísica de Canarias (he and his colleagues proposed the "Lithium test" method to actually detect this substellar objetcts). You can read a short report about brown dwarf findings at American Scientist.

Nuts... wrong link... the pic link is here.

I was going to post the same thing you just said. I clicked on the link hoping to see inspiring pictures of celestial objects. Instead I got:

- A pop-under for "World's largest online casino"
- An X10 "tiny wireless video camera" ad
- An animated banner "hit the button to win" (at least it wasn't "punch the monkey")
- A blinking purple and green "Buy Now" for Starry Night software.
- A bunch of other frame cruft
- ...and a little thumbnail of the ant nebula next to the headline. Maybe there was a story body too; I didn't notice.

Bah! With a front page like that, I'm not even going to risk clicking on any of their links. Astronomy picture of the day or the Hubble Heritage Galleryare much better sites.

People who are interested in photographic images from the Hubble Space Telescope would likely be better browsing those available from the Hubble Heritage Project. They're incredible!

--When everyone uses Windows, and Windows contains government spyware, we will be in the world's first true invincible police state.

For me, nothing compares to the Eagle Nebula (M16) pillars images. The fact that the universe contains things of such scale and beauty leaves me both wonderfully awestruck and horribly aware of our insignificance.

Actually we are both wrong -- it's three billion to five billion years in the future. :)

Peace,

-Joe G.

In any case, there are a few things you should keep in mind. First, HST is quite old now, and past its initial proposed service lifetime, IIRC, so technology has come a long way since it went up. Second, things like this are often technologically lagging even before they go up, since it can take literally decades to plan an instrument of that size. Size is the other critical thing to keep in mind. It's (relatively) easy to build huge arrays like VLT on the ground, but try getting that into orbit :). Even if you break it up into many missions and assemble in-orbit (some early plans for NGST considered that, IIRC), it would still be a monumental task (though not impossible).

So I'd say in summary that chances are HST never could have been better than Paranal, even though it's been an awesome instrument throughout its lifetime.

In any case, there are a few things you should keep in mind. First, HST is quite old now, and past its initial proposed service lifetime, IIRC, so technology has come a long way since it went up. Second, things like this are often technologically lagging even before they go up, since it can take literally decades to plan an instrument of that size. Size is the other critical thing to keep in mind. It's (relatively) easy to build huge arrays like VLT on the ground, but try getting that into orbit :). Even if you break it up into many missions and assemble in-orbit (some early plans for NGST considered that, IIRC), it would still be a monumental task (though not impossible).

So I'd say in summary that chances are HST never could have been better than Paranal, even though it's been an awesome instrument throughout its lifetime.

Actually, most of the data used by astronomers is publicly available. Try the following:

HST data archive: every HST image. Also has other mission data.

Astronomical Data Center: archive of data tables published in peer-review astronomy journals

NASA/IPAC Extragalactic Database: index of known data for other galaxies. You can get redshifts here, for example.

The software used by astronomers is also generally publicly available. For example, Debian Linux ships with IRAF, the image reduction software that most of us use (the ones who can't afford IDL anyway).

I just ran across this that would certainly explain a couple things:


The Question We are deeply indebted to you if you can help us in obtaining two representative images about: 1)the real image (picture) of a "black hole" (photographed) 2)the most distant part of the Universe ever photographed.

The Answer 1) There are no "real" pictures of a black hole. This is because black holes themselves do not emit of reflect any light (that's why they are called black holes), and they are too small and too far away to be imaged. There are images of binary star systems consisting of one normal star and one black hole, and of the central regions of Galaxies that are believed to contain black holes. There are some examples of the latter, taken with the Hubble Space Telescope, at: http://imagine.gsfc.nasa.gov/docs/ask_astro/answer s/970318d.html

But these pictures don't actually show a black hole, you need to study the motion of stars to infer that there must be a black hole.

2) Again, you may want to look at some Hubble pictures (with explanations): http://imagine.gsfc.nasa.gov/docs/ask_astro/answer s/970318d.html

These are some of the most distant galaxies ever photographed; although some quasars are believed to be more distant, they make boring photographs (they just look like a point of light).

Best wishes,

Koji Mukai


(no, this isn't my work, I just found it on a Google Search)

I just ran across this that would certainly explain a couple things:


The Question We are deeply indebted to you if you can help us in obtaining two representative images about: 1)the real image (picture) of a "black hole" (photographed) 2)the most distant part of the Universe ever photographed.

The Answer 1) There are no "real" pictures of a black hole. This is because black holes themselves do not emit of reflect any light (that's why they are called black holes), and they are too small and too far away to be imaged. There are images of binary star systems consisting of one normal star and one black hole, and of the central regions of Galaxies that are believed to contain black holes. There are some examples of the latter, taken with the Hubble Space Telescope, at: http://imagine.gsfc.nasa.gov/docs/ask_astro/answer s/970318d.html

But these pictures don't actually show a black hole, you need to study the motion of stars to infer that there must be a black hole.

2) Again, you may want to look at some Hubble pictures (with explanations): http://imagine.gsfc.nasa.gov/docs/ask_astro/answer s/970318d.html

These are some of the most distant galaxies ever photographed; although some quasars are believed to be more distant, they make boring photographs (they just look like a point of light).

Best wishes,

Koji Mukai


(no, this isn't my work, I just found it on a Google Search)

Then again, every time the Hubble is used in something new, I am impressed considering its rocky beginings and the amazing in-orbit mirror replacement that had to be done just to get it working.

Hubble's mirror was not replaced.&nbsp From STScI:

Corrective Optics Space Telescope Axial Replacement

COSTAR is not a science instrument; it is a corrective optics package that displaced the High Speed Photometer during the first servicing mission to HST. COSTAR is designed to optically correct the effects of the primary mirror's aberration on the three remaining scientific instruments: Faint Object Camera (FOC), Faint Object Spectrograph (FOS), and the Goddard High Resolution Spectrograph (GHRS).

Also, IIRC, even without the addition of COSTAR, the images we got from Hubble were better than anything else we could get on the ground at the time although obviously not as good as they could have been... :-)

Xephem (a planetarium and analysis program for linux) is very cool because it can both pull the sky from your LX200 telescope or by replacing the telescope driver with a perl script, it can download part of the sky from an online database, after which you can do realtime image processing on it.

It can also match stars in the sky to stars in the database. So far I have only been able to pull down large segments of the sky at once, but as soon as I can clear the disk space I'll be trying some other pieces of software to try and download smaller pieces of the sky. Starry Night also downloads DSS (Digital Sky Survey) images I believe.

NASA Skyview service
Multimission Archive
StarView
Software for different platforms (or check freshmeat.net)
Serious scientific platforms/data
Skyview (available at IPAC) is available as linux binary and installs quickly at 10mb. It lets you do image analysis with text commands. I have not used it a lot myself.
AstroWeb