Welcome to the Pulsar Search Collaboratory (PSC) – West!
NRAOUniversity Wisconsin – Milwaukee
West Virginia UniversityYerkes Observatory
University of Chicago
A few words of welcome by . . .
• Dr. Kyle Cudworth• Mr . . .(Sherry’s principal)• Vivian Hoette
Pretests
• The NSF grant likes to have data of before and after – so we have two(?) more short tests to take before we start!
Let’s introduce ourselves to each other. . .
Intro to project . . .
Citizen Scientists
• So much of scientific research today relies on the analysis of incredible amounts of data.
• Scientists cannot possibly look at it all – Computers do most, but human element is an
essential ingredient, as it always will be
• We already see some “citizen scientists” at work– Galaxy Zoo– Einstein at Home– Other “Zoo” type things
• Educational outreach is also an important part of any scientist’s request for grant money– Involving high school, and even middle school
students is highly desirable• Can undo stereotypes• Can ignite the interest in science• Can make science accessible to underserved students
(and to under achievers)
– Involving science teachers is also a plus!
This opportunity . . .
• National Radio Astronomy Observatory in Green Bank, West Virginia (NRAO)
• University of Wisconsin – Milwaukee (UWM)• West Virginia University (Morgantown)
Some of the people involved . .Sue Ann HeatherlyEducation Director, NRAO
Rachel RosenAstronomer,Program Director ofPSC
Maura McLughlin,Astronomer, WVU
Duncan LorimerAstronomer, WVU
From UWM
Xavier Siemens , Physicist, UWM Larry Price, postdoc, UWM
Jean Creighton, Planetarium Director
ARCC@UWM research program
• ARCC stands for Arecibo Remote Command Center
• UWM can also remotely control the GBT
More about this next time!
The group of teachers Sherry and I worked with summer 2009
Students at last May’s Capstone at WVU
So let’s see how you can get your students involved . . .
Astronomy!• It can really grab the interest of kids,• They like to ask the big questions:
– What’s out there?– How do we know?– Are there Aliens?
• Here is a way you can involve a student of any ability.
• -Sherry and Kathy’s stories
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What is radio What is radio astronomy?astronomy?
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The Visible Sky, Sagittarius Region
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The Radio Sky
Radio Astronomy is a relatively young science
Pioneer of Radio Astronomy
Karl Jansky
1928: Karl Jansky, working for Bell Laboratories discovers radio waves coming from space.
Chart recordings from Reber's telescope made in
1943.
First Surveys of the Radio Sky
Pioneer of Radio Astronomy
Grote Reber
In 1967, Cambridge graduate studentJocelyn Bell was using a radio array to study interplanetary scintillation – SURPRISE!
For this project . .
• Radio data is collected from the telescopes
• The data is screened by a computer to a certain point–Then a human must look at it to see if
it is worth a follow up• This is where students come in!
• The data is being looked at to find pulsars –spinning, neutron stars
–Pulsars signals are used to find gravitational waves.
–Pulsars are used to study interstellar space.
–Pulsars are inherently interesting in themselves!
First, some background information . . .
• The pulsar story will be told by our astronomers next time
• We will look at and review the electromagnetic spectrum, frequency, period, etc.
• Everything we know about the universe comes to us in the form of electromagnetic waves.
• Visible wavelengths are a very small part of the electromagnetic spectrum.
How do we know about the Universe?
But there is so much more to “see”!
The electromagnetic spectrum provides much information
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Electromagnetic radiationElectromagnetic radiation
A traveling, massless packet of energy --OR an oscillating electric and magnetic field Also known as: radiation, light wave, photon
Animation from Nick Strobel’s Astronomy Notes (www.astronomynotes.com)
Travels at the speed of light (by definition).
Remarkably, all radiation travels at this speed, regardless of whether is carries a lot of energy or only a little
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A light wave is a light wave, no matter how A light wave is a light wave, no matter how long...long...
Frequency:
• How fast something must oscillate to produce the wave
• The range of radio frequency is• What is audio frequency? How is it different
from radio frequencies?
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Radio Waves are NOT sound!Radio Waves are NOT sound!
Activity Time!
• (Stations set up with different em things to do)
• (or should we do frequency versus period type activity? Or both?)
The different parts of the spectrum provide us with more information
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Jupiter in visible light . . .
Can you imagine “seeing” it in radio?
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Optical and Radio can be done from the ground!Optical and Radio can be done from the ground!
Radio waves can be detected night or day
• They also can travel through dust and gas• So we can see further into our galaxy with
radio waves than with light waves.
Let’s look at a radio telescope
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Radio TelescopeRadio Telescope
Optical TelescopeOptical Telescope
Nowadays, there are more Nowadays, there are more similarities between optical similarities between optical and radio telescopes than and radio telescopes than ever before.ever before.
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At 100 m, the GBT is the largest fully steerable telescope (and the largest movable structure) in the world..
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The Advantage of Unblocked Optics
Arecibo Telescope
We will look at a smaller version!
• Itty Bitty telescope• Radio Jove• Let’s go outside . . . .
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Next: What emits radio Next: What emits radio waves?waves?
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Recipe for Radio WavesRecipe for Radio Waves
1. Hot Gases1. Hot Gases
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Electron accelerates as it passes near a proton.
EM waves are released
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2. Atomic and molecular transitions 2. Atomic and molecular transitions
(spectral lines)(spectral lines)
Recipe for Radio WavesRecipe for Radio Waves
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Gas Spectra
Neon
Sodium
Hydrogen
656 nm486 nm434 nm
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Electron accelerates to a lower energy state
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Doppler Shift
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3. Electrons and magnetic fields3. Electrons and magnetic fields
Recipe for Radio WavesRecipe for Radio Waves
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Electrons accelerate around magnetic field lines
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The radio telescope and a pulsar
A pulsar is the collapsed core of a massive star
• It is like taking the mass of the sun and making it into a ball the size of Milwaukee.
• It spins very fast, like an ice skater who has brought their arms in.
Why do they pulse?• Pulsars sweep their
beam of radio (electromagnetic) waves across the face of the earth at a very periodic rate.
beam of radio waves
magnetic field
rotation axis
What do the telescopes “see”?
Back to the telescopes:
• The basic question:• Is it a Pulsar?
– Or is it Radio Frequency Interference (RFI)?
Process . . .
• A computer program analyzes the data for possible candidates
• A “viewer” page is produced• Ratings are made and submitted• Potential pulsars are followed up with
additional observations• This is what we will learn next time!
Let’s visit the GBT control room . .