Hubble captures the sharpest ever view of Andromeda Galaxy | Hacker News Reader

Hubble captures the sharpest ever view of Andromeda Galaxy

spacetelescope.org

254 pointsgokhan62 comments

In fact [Andromeda's] full diameter on the night sky is six times that of the full Moon.

I was surprised to read this. I remember gazing at Andromeda and the full moon many years ago as an amateur astronomer, but didn't have a sense of apparent size of the two.

Anyway, I dug into NASA's archives [0] which included an image showing perspective. Thought it was pretty neat, so here you go:

http://imgsrc.hubblesite.org/hu/db/images/hs-2015-02-e-compa...

[0] http://hubblesite.org/newscenter/archive/releases/2015/02/fa...

Awesome.

I was lucky enough to see Andromeda with the naked eye while doing a transatlantic yacht race. Believe it or not it took me a couple of days to find Pegasus but then it was obvious each night as I gazed up at the sky.

We're on a collision course with Andromeda, right? Those trillion stars crashing in are going to make for a wonderful fireworks display :)

The thing is, stars are so far apart from each other that there won't be any collisions. From wikipedia: "While the Andromeda Galaxy contains about 1 trillion (1012) stars and the Milky Way contains about 300 billion (3×1011), the chance of even two stars colliding is negligible because of the huge distances between the stars."

link: http://en.wikipedia.org/wiki/Andromeda–Milky_Way_collision

You're correct, the likelihood of stars colliding is near zero, but the gas that forms stars in both galaxies will collide and that will create quite a spectacular view. It will likely resemble something like this: http://hugepic.io/bfc195a2b/4.00/2.02/-77.61

Space is full of a LOT of empty space. Maybe even more amazing to myself, is the scale works almost the same in inverse. There's also a lot of space at the tiniest scales.

Scale of our solar system: http://joshworth.com/dev/pixelspace/pixelspace_solarsystem.h...

You are right about the collision course. The two will slowly merge into a bigger galaxy like in this picture: http://cas.sdss.org/dr6/en/proj/basic/galaxies/images/752-6-...

Wikipedia also has a video but this picture also illustrates it well: https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_co...

We represented both galaxies in 3D crystal cubes in case that's of interest: http://cosmic3d.com/

Nice. I've been looking for that; only found some Japanese outfit that made one years ago, for (the yen equivelent of) $100 ... out of my price range. Glad to see yours is much more reasonable.

Curious about accuracy ... how many bubbles (stars) are etched?

There is a neat size comparison of the Andromeda galaxy (178 x 63 arc minutes) and the moon (30 x 30 arc minutes) on APOD: http://apod.nasa.gov/apod/ap061228.html

According to wikipedia "Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye or when viewed using binoculars or a small telescope." [1]

[1] http://en.wikipedia.org/wiki/Andromeda_Galaxy

Yes, exposure time (and aperture size) makes all the difference. Most of the disk is quite dim.

Another stunning thing about Andromeda to observe is its satellite galaxies. The larger satellite galaxies are easily observable in a wide-field eye-piece even by beginners. The smaller ones (globular clusters) are a little harder.

Observing the large central galaxy alongwith its satellite galaxies gives me a better sense of scale and fills me with awe.

" To capture the large portion of the galaxy seen here — over 40 000 light-years across — Hubble took 411 images which have been assembled into a mosaic image."

"The image featured here has 69 536 x 22 230 pixels and is a cropped version of the full uncropped image which has 3.9 billion pixels and covers a length of almost 60 000 light years."

Here is a link from the article that would help appreciate how detailed full resolutions is: http://www.spacetelescope.org/images/heic1502a/zoomable/

I was blown away in particular by sheer luminescence difference between galactic core and edge of the galaxy. Imagine the brightness of night sky in galactic core. That reminded me of the paper that estimated number of GRB's that would hit a planet based on where it was located - galactic core is not a hospitable place.

After being stunned by the close-up of the stars I'm tempted to download the 4.3GB original [1]. The scale was unexpected having mostly seen only resized photos before.

[1] http://www.spacetelescope.org/static/archives/images/origina...

If anyone has succeeded in downloading the original from here or elsewhere...care to provide a mirror/torrent magnet link?

What program can open such file?

From previous experiments, any program that stores image data in quad-tree order (or even just tiles, but I hate tiles) should be able to pan around such an image with little effort even if you have only a fraction of the RAM but plenty of swap space. Of course zooming out will require either the full RAM or MIP maps. But IDK a specific app.

That's a Photoshop Big file, which can be opened with Photoshop, obviously, provided your computer has sufficient RAM.

So I guess it won't be of much use with my linux box...

If the psb format can be converted to ppm format (via ImageMagick?), and image size is the issue, maybe NASA's BigView could be an option:

BigView allows for interactive panning and zooming of images of arbitrary size on desktop PCs running linux. Additionally, it can work in a multi-screen environment where multiple PCs cooperate to view a single large image. Using this software, one can explore -- on relatively modest machines -- images such as the Mars Orbiter Camera mosaic [92160x33280 pixels].

http://ti.arc.nasa.gov/opensource/projects/bigview/

I've done some searching, but I haven't found any software that supports .PSB on Linux. Perhaps there's a plugin for The GIMP that would work, but I was unable to find one, sorry...

It's probably more trouble than it's worth, but you could install Wine and Photoshop on your Linux box, or find someone with a Windows machine and Photoshop who could convert the file to another format that you're able to use, like .PNG for example.

ImageMagick?:

http://www.imagemagick.org/discourse-server/viewtopic.php?t=...

Amazing how much large scale structure is visible in that image.

In case you don´t know, Andromeda is approaching the Milky Way at about 110 km per second and will collide with our galaxy. See NASA collision animation and also the amazing illustration of how big we'll see Andromeda Galaxy (in 3.75 billion years): http://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_col...

For those unfamiliar with astrophotography, there are a few neat things to note about this image. Most of the larger points of light that have what looks like a cross going through them are actually stars in our own galaxy between the Earth and Andromeda.

The crosses, or spokes, through each of the stars is caused by the struts holding Hubble's secondary mirror in place above the primary mirror. Every poinpoint of light in this picture actually has these spokes, but they are only really visible on the biggest, brightest spots.

This is also visible in Hubble's Deep Field photos as there are numerous local stars in the foreground.

The reddish, fuzzy, oblong objects that are a bit bigger are other galaxies far past Andromeda. Most appear red because of a side effect on light traversing such a long distance before reaching us called redshift.

Just incredible. The moment when you realize that what you thought was CCD noise is stars...

So true :). Here's an equally amazing zoomable picture of the Milky Way: http://www.eso.org/public/images/eso1242a/zoomable/

Zoomed to max and my mind was blown. What immediately came to my head was: imagine if each of those shiny points in this cloud is an atom. Our whole civilization is nothing more than a surface irregularity on one of "electrons" orbiting one of those dots. Both drives home the sense of scale, and lets one marvel at the recursivity of patterns at different scales in the universe.

This stuff gives me an unreasonable fear of getting lost. If you had some magical hyperdrive ship and bumped the controls with your elbow at the wrong moment, you'd never find your way back home.

Just take a pulsar map, like the one on the voyager golden records.

That happens frequently to people in Pohl's Heechee Saga.

http://en.m.wikipedia.org/wiki/Heechee

This is impressive!

Edit: We really can't be alone in this universe.

I wouldn't believe you if I didn't see this same thing in my backyard. When I point my telescope (a good ole dob 10' light bucket) into the sky on a dark night when the milky way is near zenith, it looks like someone has frozen a single frame of white noise on an old crt tv set but with hints of color.

What's even more amazing is that we only see the stars hot enough to be visible. There is a HUGE amount of stars not detectible woven into that galactic fabric hiding from us.

We are small.

Can't wait to see what the James Webb Telescope[0] will show us after it goes up in late 2018.

[0] https://en.wikipedia.org/wiki/James_Webb_Space_Telescope

Are the "background noise" of the images also stars? It's the first time I realize the darker parts of the universe, while zoomed in, looks disturbingly noisy and bright.

From article: "The whole galaxy contains over one thousand billion stars." so presumably yes.

I would even say that we are only seeing brightest stars and clusters of stars.

And quite a few of the 'stars' are galaxies themselves. Lots of red-shifted spirals.

Yeah, when you're looking at the core of Andromeda, you're seeing countless stars fairly close together. That galaxy is larger than ours and contains an estimated one trillion stars.

The best example of "dark" parts of the sky not being really dark is the Hubble Ultra-Deep Field. https://en.wikipedia.org/wiki/Hubble_Ultra-Deep_Field It's pretty hard to find truly dark areas of the sky when you're looking far enough. The mind-blowing part is that almost all of those bright spots are galaxies, not stars.

I got similar large image printed and hang in my living room. It is milky-way panorama, poster has 2x5 meters, 100Kx300K pixes, pretty nice. One can see every tiny nebula.

I believe this image now has the world record for largest image of Andromeda Galaxy/M31

Previously, this was 310 million pixels (http://www.robgendlerastropics.com/M31NMmosaic.html)

The Hubble photo is 3.9 billion pixels.

"Oh, cool! I can split this into images and print out a full color wall mural of Andromeda!"

looks at prices of poster printing

Professional printed glossy full bleed posters: $30ea (x25=$750). Ouch. Wall mural printing services don't seem to list custom pricing, but I assume it's less. A cheaper alternative is KISS Printing, which at $0.15 per 12.5"x18.5" printable area would be around 10x10, so about $15.... but you also choose how much profit they make, so figure at least $30 profit, since half goes to a charity... $45 is very affordable, though not as nice prints

I've looked at the zommable picture. When I zoomed to the maximum, I saw a lot of noise in the picture (and a arather regular one). Does it mean that although the resolution is pretty impressive, the noise make it less "useful" ? Just asking, I've 0 knowledge in this area.

Second question, just out of curiosity, would it be possible to look at closer objects like Mars or the moon ? We'd have a pretty good image too ?

About the Mars question, consider the fact that the Andromeda galaxy, although faint in the sky, takes up 5 times more room in our night sky than the moon does. It's really huge.

Mars in comparison is minuscule in our night sky. It's just a tiny blob of light.

"..the Andromeda galaxy, although faint in the sky, takes up 5 times more room in our night sky than the moon does."

Correct, although wikipedia says 6 times and adds a clarification:

"Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye or when viewed using binoculars or a small telescope." [1]

[1] http://en.wikipedia.org/wiki/Andromeda_Galaxy

It was explained quite well recently - Hubble can't look at the Moon(or the Earth for that matter) because it's moving way too fast relative to either of these two bodies to take a non-blurry picture.

Randall Munroe took the question as part of his What If series.

https://what-if.xkcd.com/32/

Earth - Hubble is moving too fast to get decent close-up imagery, the distance is too small, and frankly Hubble just wasn't designed for it (as opposed to spy satellites of the major powers). Hubble does use the earth to calibrate its cameras, though.

Randall gives examples of how imagery might turn out.

Moon - speed's an issue, but less so, especially if you're imaging a large region

Here's an example: http://hubblesite.org/newscenter/archive/releases/2012/22/

Mars - Hubble has targeted this planet lots of times.

Some examples: http://hubblesite.org/gallery/album/solar_system/mars/

No knowledge either, but it looks to me like the "noise" is actually made of stars.

Maybe you didn't zoom far enough? At sub-maximal zoom, there is aliasing resulting from a lack of low pass filtering before the resolution reduction. That looks a bit like sensor noise.

I certainly remember Hubble taking pictures of the moon. A quick google found http://www.nasa.gov/vision/universe/solarsystem/hubble_moon....

That isn't noise. Our own galaxy looks similar to that when looking at it in person with a telescope. This is a truly incredible image.

This picture is awesome. Looking at it, I get a deep feeling of loneliness and complete loss in this gigantic space.

As someone already said, "We can't be alone in here..."

Also, this is a nice reminder of the quality of engineering that went into Hubble. This satellite is truly an incredible piece of work for being relevant and useful so much time after its supposed "expiration date"! :)

Looking at pictures like this I get the same feeling as when I'm swimming in very deep water, loneliness and chills.

That is an awesome picture. The JWST should have "Galaxies in the Mirror are Closer than they Appear" somewhere on its primary mirror :-).

It is fortunate that the jets coming off the galactic black hole in the middle of Andromeda aren't pointed our way, that would have made short work of life on Earth.

What a fantastic image. Just imagine being able to map the entire sky dome with this level of detail...

The funny thing, is that to the naked human eye, being in a nebula would look like you are in a big ball of brown dust.

For those wanting to download the larger versions: http://hubblesite.org/newscenter/archive/releases/2015/02/im...

About 1/16th of the way out from the center, there's a yellow arc. (It's most visible on the zoom tool.) What is it?

As you zoom in on that area more and more, the yellow arc seems to go away, so I'm guessing it's some kind of image compression artifact and it's just dust lanes like elsewhere in the galaxy.

Inner spiral arm?

In a couple billion years we'll be able to see it in much more detail ;-)

502 Bad Gateway. :(

I had to give it a couple tries, but it loaded

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