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Night Sky: Wave(s) Hello

Hi folks, James McCue here. I recently attended an NIU STEMCafe event about the Night Sky. Here's a recap of the most interesting topic I've encountered in a while: Cosmic Microwave Background Radiation, or CMBR.

Drs. Amy Bender and Lindsay Bleem both for the Argonne Nat'l Laboratories, and were willing to share some of the surface details about their work. Both are NIU alumni, which was a satisfying realization. They work together on Exploring the Universe with a giant telescope at the South Pole. In their words, "Man has always looked at the skies" and their echoed passion could not be any more obvious. They spend most of their time at the South Pole, where eyelashes will freeze if one isn't careful, measuring changes in the Light and electromagnetic(EM) spectrum, a science known as Spectroscopy. They measure and qualify the changes in these spectrums that occur all over the known universe.

PPT Slides available
Spectroscopy Slide

Dr. Bender spent a good portion of time discussing the M16 Nebula, which is also referred to as the "Pillars of Creation." The reason they look here is because this is often thought to be the origin point of the so called Big Bang that theoretically set the Universe in motion, and it has the highest known concentration of Cosmic Microwave Background Radiation, or CMBR. Readers who are also avid Marvel Cinema fans may recognize CMBR from its prominent role in the recent WandaVision miniseries. CMBR is a sort of scientific footprint left behind by the beginning of everything, and its trails and changes can be tracked back across space and time.

The SPT-3G is the giant telescope platform's heart, fully fabricated in-house by Argonne. The micro wavelengths it can observe are as thin as 1.5mm. How do the Argonne scientists achieve this? To get a smaller photo clearer, they need a bigger telescope.

The engineers for the giant telescope use 3 mirrors and 3 lenses for a complex refraction/magnification combo. The biggest mirror is 10 meters in diameter. This 700,000 LB system can measure at a resolution of approx. 1 arcminute - the thickness of a card at arm's length. The light/EM detectors are always kept cryogenically sealed in a vacuum that retains -459 Degrees F. The South Pole Location helps the scope by operating with reduced light pollution or impeding orbital satellites, not to mention helping ensure the cryogenics stay cold.

Many of the pieces of necessary technology did not exist before the scientists were able to conceptualize what technology they would need. This is where the E in STEM, Engineering, plays a key role in ensuring the technical success of the telescope. The engineers who were responsible for the SPT's structural success needed to take into account unique features of Antarctica, such as a ground made entirely of compacted snow. You read the number correctly earlier, a 700,000LB telescope sits on nothing but compacted snow. The lab moors separately from the telescope into the snow, but they can dock together for maintenance. In this way, the engineers protect workers against potential calamitous conditions without compromising either portion of the South Pole Telescope platform.

To help us visualize the spectrum of light waves we cannot process, the Drs. put up a photo that captured those waves, featured above between their photos. They attribute the scene to be much like Van Gogh's Starry Night, and I tend to agree with them. Nature sure is beautiful.

After the presentation, I reached out to the speakers and was able to secure a set of their presentation slides. If you'd like to view them in more depth, download them from the link below!

Download PDF • 116.96MB


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