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| Dear
SEED,
I am a high school student working on a research project
in Earth Science. I wonder if you could assist me in
finding an astronomer to interview and learn more about
this job field.
Thank you very much,
Jamie
|
| We put Jamie in touch with SEED Expert José
Navarro. Here is their exchange: |
 Jamie,
Michael Tempel from SEED has contacted me regarding your research project.
I was a professional astronomer (working mostly on pulsar
radioastronomy) before I joined Schlumberger three years ago.
I would be happy to assist you with the interview. Just let
me know what to do.
Cheers,
José
Navarro

José,
Thank you for contacting
me. I have chosen to research a career, specifically what it is to be
an ‘astronomer’. I
will write again in a few days when I have a couple questions organized.
But for now,
what is pulsar radioastronomy?
Again, thank you very
much,
Jamie

Jamie,
Radioastronomy is
the part of astronomy that uses radiotelescopes to look at the sky instead
of normal optical telescopes. This means that radioastronomers don't observe
light from the stars, but see instead the radio waves that they produce.
Thus the bright objects in radioastronomy are those that produce the most
radio waves and not the ones that produce the most light. These objects
are called pulsars.
Because pulsars emit
much more energy in the form of radio waves than in visible light, they
are normally studied with radiotelescopes. In fact, only a handful of
the perhaps 1000 known radio pulsars are visible with optical telescopes.
Pulsars are a special
type of star that has undergone some sort of stellar collapse (most likely
during a supernova event) and have become incredibly small and dense,
as well as fantastically magnetized and rapidly spinning. In the SEED
web page you can find out more about pulsars, but please do ask if you'd
like clarifications or just want to know more.
I look forward to
hearing from you soon.
Cheers,
José

Hi José!
Thanks for describing
radio-astronomy! I think I understand the radio wave part of it, but the
pulsar half is a little confusing. Is this kinda what is going on???
The star dies, explodes,
dissapears, but leaves behind radio waves so that scientists can "track"
it and learn more about the way our universe works?
Jamie

Jamie,
Pulsars
were discovered by accident, with a radiotelescope. What we know from
direct observation is that they emit lots of radio energy in a tightly
focused beam, and that the pulses that we observe are the moments during
which the beam points in our direction. Think of them as lighthouses.
In fact, they emit all kinds of energy in addition to radio waves, including
light in this beam, but they are generally too faint to be seen with an
optical telescope.
The beam comes from
the fact that pulsars have very strong magnetic fields (larger than we
can create in the lab) and that they rotate very fast (some pulsars rotate
so fast that the surface at the equator moves at one tenth of the speed
of light). The combined effect is that of a dynamo, where the voltage
created at the magnetic poles is so large that it produces all kinds of
particles and emissions (hence the light and radio waves). Hence the beam.
Let me know if you
need more details about any of this, or if you have other questions.
Cheers,
José

Hi José!
What is a good visual
aide I can use during my project presentation?
Thanks,
Jamie

Hi Jamie,
I would expect you
to show some astronomical pictures: a radiotelescope, some optical images
of pulsar neighborhoods, things like that. If you are going to talk about
pulsars, then you can also play an audio tape of three pulsars that is
quite startling, which you can find at http://pulsar.princeton.edu/pulsar/multimedia.shtml
José

|

Very Large Array
|
José,
Hi! How are you? I
have my project finished, I'm just waiting for my teacher to let me know
when I'm supposed to present it.
I started with Karl
Jansky and Grote Reber, giving a little bit of history as well as including
some pictures of their telescopes that I downloaded off the internet.
Then I described the telescopes (with a picture) and the graphs/charts.
After that I included a slide on the VLA-Goldstone system. (What does
VLA stand for?) Then a bit about what radioastronomy is and when it began
to develop.
Thanks,
Jamie

Jamie,
Congrats! It must
feel good to be done, with only the final presentation left. What you
have prepared sounds good. I hope you are ready and that it all goes well.
VLA stands for Very
Large Array. They have a web site at www.aoc.nrao.edu/vla/html/VLAhome.shtml
if you are interested one day. It's where I worked for two years before
going into oil exploration with Schlumberger. They and other observatories
like Arecibo (www.naic.edu)
have summer internships for seniors in high school.
Cheers and good luck,
José
 If you
would like to find out more about a career in science or engineering,
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