Infrared Telescope Lifts Off

An anonymous reader writes "On its Delta 2 Heavy-Lift vehicle, the Space Infrared Telescope (SIRTF) successfully launched to its solar orbit at 1:35 AM (EDT). As a result of the expansion of the Universe, most of the optical and ultraviolet radiation emitted from stars, galaxies, and quasars since the beginning of time now lies in the infrared. How and when the first objects in the Universe formed will be learned in large part from this observatory's infrared observations."

Comments

Ball Aerospace Link

[evilninja]

I work at Ball Aerospace... I thought some of you might like to see the BATC stuff.

Re:Infrared, eh?

[Anonymous Coward]

> So, this means it will be able to see through those bikinis, eh?

First you'd have to spot one among the heavens. Aren't you being a tad optimistic?

Re:The electromagnetic spectrum

[Baron_Yam]

Umm, d00d, I think you're supposed to understand that light was in those ranges when it was created, but redshift due to the expansion of space and the massive distances this light has travelled have resulted in it shifting down-spectrum into the infrared.

Excellent development

[Ompaloskeptic]

This is great. The more telescopes we can get in orbit, the better. Especially those in different spectrums. There's so much data that the earth is being bomarded wioth constantly that is untapped. We're slowly getting more and more of this data and leaning so much about the universe because of it. I lok foward to the findings of this telescope.

60 years

[solarlux]

God, I hope they calculate the trajectories right or there might be an interesting "meteor" shower in about 60 years...

CNN Article

Unlike most astronomical spacecraft SIRTF will not be orbiting the Earth. Instead, it will be put into orbit around the sun. "SIRTF will be following the Earth around the sun, kind of like a faithful puppy dog," astronomer Michael Werner said. The solar orbit increases the lifetime of the spacecraft. SIRTF will gradually lag further and further away from the Earth until it's too far to be detected. But in about six decades the Earth will "catch up" with SIRTF, like a race car lapping another race car.

Right, but they're talking about the Red Shift

[dido]

Well, I suppose you know about the red shift due to the general expansion of the universe? The most distant objects in the universe are now receeding away from us at such a massive rate that the visible light they emitted has been so far red shifted as to wind up in the infrared region. There's a Doppler effect for light that causes light from an object moving very quickly away from an observer to reach the observer at a lower frequency than what was transmitted (the red shift), just like a car moving away from you makes sounds at a lower pitch than were it standing still or moving towards you. Because of Hubble's law, the farther away an object is, the faster it's moving away from us, and consequently, the greater the Doppler effect. This infrared probe is designed to view objects that have been so far "red shifted" as to apparently be emitting infrared radiation.

Re:Digital Cameras in freezers on rockets.

[Betelgeuse]

Actually, it can get pretty damn hot with the Sun up there. If the satellite were out of the solar system, then it is true that cooling wouldn't be much of an issue. But, with the Sun right next door (astronomically speaking), it's very important that you have good cooling. In fact, this will only be a 2 year mission, due to the fact that the cooling system (liquid helium, I believe) will only last for that long. . .

Re:The electromagnetic spectrum

[SillySlashdotName]

the optical and ultraviolet regions do not lie in the infrared region.

Yeah, but...

Ultraviolet range is anything with a frequency above violet light, optical is the frequencies between violet to red, and infrared is anything with a frequency below red light.

Light that was emitted at an ultraviolet or optical wavelength can be slowed down in frequency - Dopler shift is probably the most well known. Heard of red-shift?

Any frequency - gamma rays to visible, if red-shifted far enough is now infrared, and that is what this telescope is looking for.

The entire statement you selectively quoted is:
As a result of the expansion of the Universe, most of the optical and ultraviolet radiation emitted from stars, galaxies, and quasars since the beginning of time now lies in the infrared. I added emphasis to the important part you left out.

So, while you are pedantically correct in that "Optical (visible?), ultraviolet and infrared are distinct parts of the electronmagnetic spectrum. [T]he optical and ultraviolet regions do not lie in the infrared region.", what was originally said is correct and your post does not correct anything.

By the way, unless you go with a definition of red and violet based on specific wavelengths, the designations "ultraviolet" and "infrared" are subjective, and may overlap with visible light to some extent. I am saying that MY definition of where the frequency gets high enough to no longer be visible and therefore becomes "ultraviolet" may not be the same point for you. It should be relatively close, but almost certainly not the exact same as it is subjective.

Some other projects along the same lines....

[supermojoman]

Here are some links to other projects that have similar goals - examining expansion of the universe, faraway objects, etc. They also have sophisticated infrared imaging capabilities. The James Webb Space Telescope (formerly Next Generation Space Telescope) is the successor to Hubble, and Supernova/Acceleration Probe which, from what I remember, locates potential supernovae by examining data taken at fixed ground locations then points an orbiting camera at the calculated location to collect radiation data. Really interesting stuff!

Technology

[ZenArchitect]

As a member of the team that is building the ground system for the science center that will be the primary interface between the public and the telescope I'm happy to say that code is all Java based. We have managed to combine the best that the open source community has available with a couple of commercial products to be a very productive development team. Here is a sample of what we are developing:

• "Thick" Java Client for proposals, planning and data retieval - yes folks, Java on the desktop does work
• Estimating and visibility servers - many computing drone managed by a J2EE server
• Web services access to all of the public data produced by SIRTF - Perl, .NET, C++ is doesn't matter you can all get the data

Oh, I forgot the mention.... there is not a single Windows box in the operations system. It's all Unix based because... well you know why don't you?

Re:Technology

[Coelacanth]

...I'm happy to say that code is all Java based...

Oh, so THAT'S why it's shaped like a giant coffee maker.

Re:Digital Cameras in freezers on rockets.

[wass]

You don't need laser cooling to get below 1K.

Using a simple pumped He3 system, which we just set up in our lab last week, you can easily reach about 300 mK. You use a pumped He4 bath to surround your insert, keeping it at about 1.5 K, and then pump the He3 with a charcoal sorb, to get to 300 mK. In space, you can use blackbody radiation to cool you to the ambient temperature of space (I forget whwat it is, somewhere between 3 to 7 K), and then use He3 pumping to go colder.

You can also get to about 10 mK if you use a dilution regridgerator, which uses a mix of He3 and He4 and relies on changes of entropy as you add them together, and then separate them out.

However, this all assumes that the highest CCD's need to actually go this low. But if for some reason this is needed, these refridgeration techniques are much more efficient and easier than laser cooling. Laser cooling is when you need to go COLD, like microKelvins.