Sue Ann Heatherly, Ron Maddalena National Radio Astronomy Observatory Quiet Skies Project The QS project was initially developed as a student project. Goal: to introduce radio astronomy to students through an inquiry-based project to measure radio frequency interference. We call the project “Quiet Skies” : quiet being the radio equivalent of “dark skies”. Green Bank, WV you see here, has pretty quiet skies.: rural, mountains, sparsely populated, nat’l forest surrounds the observatory Sue Ann Heatherly, Ron Maddalena National Radio Astronomy Observatory

This series of radio images of Orion is a tip of the hat to “Globe at Night”, and also shows the universe revealed by radio astronomy. Image 1: optical “image” from a planetarium program showing the stars of orion, and green outlines where there are nebulae Image 2: radio image showing ionized hydrogen. Note how there is good agreement with the nebulae Image 3: atomic hyrdrogen. Very different. Galactic plane begins in the upper left. Image 3: molecules ( Carbon monoxide)-- shows giant molecular clouds where new stars form.

In fact, this single radio image of a large swath of sky tells much of the story of radio astronomy. In this one image are distant galaxies and quasars which contain super massive black holes in their cores, supernova remnants that may harbor pulsars, and sites of active star formation. In fact the blue-ish color of the background is no accident, but an indication of faint radio radiation permeating the entire universe… the cosmic microwave background.

Why Dark Skies/Quiet Skies? Optical and radio astronomy can be done from the ground! To detect gamma rays, xrays, UV etc. you have to get above the earth’s atmosphere (thank goodness). Visible light and radio waves penetrate to the ground, making it possible to build large complicated instruments, which can be upgraded, repaired, maintained! Credit: Windows to the Universe, thence to NASA/STSCI/JHU

Atacama Large Millimeter Array NRAO Telescopes Very Large Array Green Bank Telescope Very Long Baseline Array Atacama Large Millimeter Array We’ve made use of this “radio window” over the last 50 plus years. NRAO telescopes, just a subset of large radio observatories around the world. Mention some? Radio telescopes are passive devices we don’t transmit ( ususally).

Got a cell phone on Titan? Why quiet skies? Got a cell phone on Titan? We can hear you now! This plot shows the signal we received from the Huygens probe as it descended through Titan’s atmosphere. Huygens transmitted about the same amount of power as your cell phone. Of course by the time it gets to us, the inverse square law has reduced the power by?

Why quiet skies? 0.00000000000000000000000001 watts/m2/Hz Before click describe our unit of “apparent brightness” 1 Jansky equals: then click

Astronomers are not the only group interested in the radio spectrum Astronomers are not the only group interested in the radio spectrum. Mention only the bright yellow areas are reserved for radio astronomy. And of course astronomers want to study objects at frequencies NOT assigned to radio astronomy as well! http://www.ntia.doc.gov/osmhome/allochrt.html

Quiet Skies Project and IYA Two Flavors: 1. Be an Interference Detective : AM Radio Scavenger Hunt of any interior space. Can be “Try it at Home”, or guided activity. Limited to AM Frequencies. Kit plus curriculum for a classroom. Loan program. We want to figure out how to modify what we have for use during IYA, at places like museums. Cool point– this can be a daytime activity. One way we can go is this way. We start using the stuff at the tables now. Get them to participate by pulling out electronic keys etc.

Quiet Skies Project and IYA 2. Quiet Skies Kits: Contain sensitive instrument which can detect RFI at Frequency range of 800-1700 MHz ( scientifically interesting). Loan program. 500 units x 10-20 locations throughout IYA. Measurements reported to NRAO data base resulting in… the radio version of…

Anatomy of a Quiet Skies Detector Here let people open up the QSDs, and check them out. Explain.

Show the transmitter, plug it in and out, show change in displayed power.

Ask, at what F is the transmitter transmitting?

http://www.gb.nrao.edu/php/quietskies Most important for IYA: Public will enter RFi measurements to a database via the web as seen here. Database is maintained by NRAO.