Tag: jets

An ultradeep image that's *full* of galaxies!

By Phil Plait | March 23, 2012 6:00 am

What happens when you take a monster 4.1 meter telescope in the southern hemisphere and point it at the same patch of sky for 55 hours?

This. Oh my, this:

[Click to embiggen.]

OK, I know. At first glance it doesn’t look like much, does it? Just a field of stars. However, here’s the important bit: I had to take the somewhat larger original image and reduce it in size to fit my 610-pixel-wide blog. So how much bigger is the original?

It’s 17,000 x 11,000 pixels! If you happen to be sitting on a T1 line, then you can grab this massive 250 Mb file. And I surely suggest you do.

Because yeah, the brightest objects you see in this are stars. Probably a few hundred of them. But you have to look at the bigger image ! Why? Because what’s amazing, truly jaw-dropping and incredible is this:

There are over 200,000 galaxies filling this image!

Ye. Gads.

Here’s a zoom of the image, centered on what looked to me to be one of the biggest galaxies in the frame, a nice edge-on spiral.

With the exception of a handful of blue-looking stars, everything in this zoom is a galaxy, probably billions of light years away. Those tiny red dots are galaxies so far away they crush our minds to dust: we’re seeing them with light that left them shortly after the Universe itself formed.

This light is ancient. And it came a long, long way.

By the way, that picture of the spiral there is not even at full resolution! Just to give you an idea, I cropped out just that galaxy in the full-res image and inset it here. If you want to find it in the full frame, it’s about one-third of the way in from the left, and one-third of the way down from the top. Happy hunting.

[Edited to add: I forgot to add that this galaxy is warped! See how the disk flares up on the left and down on the right, just a bit? This is very common in disk galaxies, and our own Milky Way does it too (see #9 at that link). It's usually caused when a nearby galaxy's gravity torques on the stars in the disk.]

These images were taken with VISTA, the European Southern Observatory’s Visible and Infrared Survey Telescope for Astronomy (VISTA), a 4.1 meter telescope in Chile. This huge image is actually composed of 6000 separate images, and is the single deepest infrared picture of the sky ever taken with this field of view. Hubble can get deeper, for example, but sees a much, much smaller part of the sky.

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CATEGORIZED UNDER: Astronomy, Pretty pictures

Black holes spin faster after eating each other

By Phil Plait | June 8, 2011 7:00 am

When it comes to black holes, there are some things we know a lot about them — in general. How they form, how they affect space around them, how they eat matter.

The details, though, are maddening. We know, for example, that black holes spin — as odd as that may sound — but how they get that spin and how spin changes over time is elusive knowledge.

A new study has given us an idea of that now, though. Here’s how this works: we see that as matter falls into them, some black holes generate twin beams, called jets, which shoot away from their poles. We see this from black holes that form when stars explode, and we see them in the supermassive black holes that inhabit the centers of all big galaxies, too. We know that various physical features of the jets are tied to the rate at which the black holes spin, and this new study makes this connection more clear. The astronomers used computer models to correlate spin to the jets, and observations appear to confirm these models.

Two very interesting results came out of the study. Read More

CATEGORIZED UNDER: Astronomy, Cool stuff, Top Post

Spitzer sees star spew spurious spouts

By Phil Plait | April 4, 2011 5:25 pm

Spitzer Space Telescope is an orbiting infrared observatory. It ran out of coolant a few years back — needed to keep its highly sensitive IR cameras working — but before it did, it took this amazing image of a young star blasting out twin jets of matter:

Neat! [Click to collimatenate.]

The star is called Herbig Haro 34, and is only a few million years old. Stars that young rotate rapidly, have fierce magnetic fields, and thick disks of material surrounding them (out of which planets might form). All these things together help focus twin beams of matter called jets, which blast away at high velocity from the star’s poles. We see these quite often around young stars.

But the jets blowing off of HH 34 are weird. They aren’t symmetric.

Astronomers figured they should be. Sometimes the jets blow out knots of gas or sputter a little. And when that happens, whatever forces acting on the star and disk should act on both jets at the same time. But that’s not the case for HH 34: the jet on the right does the same thing the jet on the left does, but only after a 4.5 year delay!

Figuring this out at all wasn’t possible until this Spitzer image was taken. Before, visible light images only showed one jet:
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CATEGORIZED UNDER: Astronomy, Pretty pictures

Hubble sees baby stars eating sandwiches and blowing bubbles

By Phil Plait | March 2, 2011 6:52 am

When a human is a baby, it has a mass of a few kilos and eats milk.

When a star is a baby, it has a mass of an octillion tons and eats sandwiches a trillion kilometers across.

Don’t believe me? Well good, because I’m being a little metaphorical. But still, this newly released Hubble image backs me up:

Isn’t that gorgeous? You can get a bigger version, or a huge 3873 x 3943 pixel image. But what is it?

It’s a view of M43, a part of the vast Orion nebula complex, separated a bit from the more famous Orion Nebula. Like its big brother, stars are forming here… and I can show you how I know.
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CATEGORIZED UNDER: Astronomy, Cool stuff, Pretty pictures
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