solar

Radio Astronomy: 

Radio Astronomy Prepared by Marcia Barton and Karen Gram July 28, 2006

Overview: 

Overview Optical Astronomy The Electromagnetic Spectrum Radio Astronomy Project Objective Data from Project Conclusions

Optical Astronomy: 

Optical Astronomy This optical wavelength picture shows the large spiral galaxy M31 (also known as the Andromeda Galaxy) and its small companions M32, lower center, and M110, to the upper right. Andromeda is the Milky Way’s closest large neighbor at a distance of about 2.2 million light-years, and it is very similar in appearance to, and slightly larger than, the Milky Way. B. Schoening (National Optical Astronomy Observatories) and V. Harvey (University of Nevada, Las Vegas)

Pinwheel Galaxy(M33, NGC 598): 

Pinwheel Galaxy (M33, NGC 598) M33 in the constellation Triangulum is a prominent nearby spiral galaxy about 3 million light-years away.

Whirlpool Galaxy(M51, NGC 5194/5) : 

Whirlpool Galaxy (M51, NGC 5194/5) This showpiece in Ursa Major is likely one of the finest and most photographed objects in the night sky.

Hydra Cluster of Galaxies (Abell 1060) : 

Hydra Cluster of Galaxies (Abell 1060) Two nearby stars frame this cluster of galaxies in the constel-lation Hydra.

Solar System: 

Solar System Mars Moon Image courtesy of Nasa Voyager 2 Nasa photo Saturn REU program, N.A.Sharp/NOAO/AURA/NSF

What is an Electromagnetic Wave?: 

What is an Electromagnetic Wave? Radio waves, television waves, and microwaves are all types of electromagnetic waves. They only differ from each other in wavelength. Wavelength is the distance between one wave crest to the next.

Slide9: 

Waves in the electromagnetic spectrum vary in size from very short gamma-rays smaller than the size of the nucleus of an atom to very long radio waves the size of buildings.

Move about Wavelengths…: 

Move about Wavelengths… One way we measure the energy of an electromagnetic wave is by measuring its frequency. Let’s do an activity to show how wavelength and frequency are related! Frequency refers to the number of waves a vibration creates during a period of time—like counting how frequently cars pass through an intersection.

Wavelength and Frequency: 

Wavelength and Frequency In general, the higher the frequency, or number of waves, the greater the energy of the radiation. In other words, the shorter the wave, the higher the energy.

Electromagnetic Waves: 

Electromagnetic Waves

Radio Telescopes: 

Radio Telescopes Because the wavelengths of radio light are so large, a radio telescope must be physically larger than an optical telescope to be able to make images of comparable clarity. Very Large Array (VLA) Radio Telescope in New Mexico seen from the air

Can you find your teacher inside the VLA Radio Telescope?: 

Can you find your teacher inside the VLA Radio Telescope? Image courtesy of NRAO/AUI Image courtesy of Robyn Harrison

Radio Astronomy: 

Radio Astronomy Image courtesy of NRAO/AUI and Inset: STScI NGC 326 – Data from the Very Large Array Radio Telescope in New Mexico is the first direct evidence that black holes actually do coalesce

What is Radio Astronomy?: 

What is Radio Astronomy? Many astronomical objects emit radio waves, but that fact wasn't discovered until 1932. Since then, astronomers have developed sophisticated systems that allow them to make pictures from the radio waves emitted by astronomical objects. Image courtesy of NRAO/AUI and A. C. Boley and L. van Zee, Indiana University; D. Schade and S. Côté, Herzberg Institute for Astrop.

How can radio waves “see”?: 

How can radio waves “see”? Objects in space, such as planets and comets, giant clouds of gas and dust, and stars and galaxies, emit light at many different wavelengths. Some of the light they emit has very large wavelengths - sometimes as long as a mile! These long waves are in the radio region of the electromagnetic spectrum. An optical telescope could not see this object in space because it would be blocked by the giant dust and gas clouds. Radio ways can pass right through the dust and gas, so that an image can be formed. Image courtesy of NRAO/AUI and David Thilker (JHU), Robert Braun (ASTRON), WSRT

Why Use Radio Telescopes?: 

Why Use Radio Telescopes? Radio astronomy can be done during the day as well as the night. Radio astronomy has the advantage that sunlight, clouds, and rain do not affect observations. Some celestial objects can not be seen in the visible part of the spectrum but do emit radio waves, so they can be imaged. “Radio telescopes are used to measure broad-bandwidth continuum radiation as well as spectroscopic features due to atomic and molecular lines found in the radio spectrum of astronomical objects.” Radio telescopes can detect atoms and molecules that can not be seen with an optical telescope. These atoms and molecules tell scientists important information about how stars and galaxies form.

The Milky Way: 

The Milky Way This composite picture shows the distribution of atomic hydrogen in our galaxy. Image courtesy of NRAO/AUI

The Milky Way in Different Wavelengths: 

The Milky Way in Different Wavelengths Seen in the infrared wavelength NASA/CXC/M.Weiss Jodrell Bank Mark I and Mark IA, Bonn 100-meter, and Parkes 64-meter Seen with radio waves in the 408 Mhz frequency Seen with the Chandra X-Ray telescope Diffuse Infrared Background Experiment (DIRBE)

Radio Astronomers Have Discovered a Lot About the Milky Way!: 

Radio Astronomers Have Discovered a Lot About the Milky Way! With radio telescopes, astronomers have discovered The shape and size of our galaxy! The black hole in the center of our galaxy! Stars forming and dying! Image courtesy of NRAO/AUI and N.E. Kassim, Naval Research Laboratory

Let’s take a closer look at some astronomical objects in optical, radio and other wavelengths!: 

Let’s take a closer look at some astronomical objects in optical, radio and other wavelengths!

Comparison of Solar Energy Output Variations Over Three Days in Different Frequencies: 

Comparison of Solar Energy Output Variations Over Three Days in Different Frequencies Prepared by Marcia Barton and Karen Gram July 28, 2006

Project Overview: 

Project Overview We used the small radio telescope to measure the energy output of the sun on three separate days at approximately the same time each day, then compare the radio images with optical images of the sun at as near the same time as we could obtain. We also look at the raw data we obtained from the small radio telescope to see if that data would give us more detailed information than the raster map. Screen shot of the small radio telescope operating software.

Project Overview: 

Project Overview Using the small radio telescope, continuum measurements were taken in the default frequency of 1420 MHz. A 25-point grid scan was used to obtain the raster map.

Images of the Sun On July 24, 2006: 

Images of the Sun On July 24, 2006 Raster map imaged by the small radio telescope SOHO Magnetogram image taken July 24, 2006

Images of the Sun On July 24, 2006: 

Images of the Sun On July 24, 2006 Raster map imaged by the small radio telescope SOHO Extreme Ultraviolet image taken July 24, 2006 Optical wavelength of sun taken July 24, 2006

Images of the Sun On July 25, 2006: 

Images of the Sun On July 25, 2006

Images of the Sun On July 25, 2006: 

Images of the Sun On July 25, 2006 Srt raster map 7.25.06 SOHO Extreme Ultraviolet images 7.25.06

Images of the Sun On July 26, 2006: 

Images of the Sun On July 26, 2006 Optical sun taken by the National Solar Observatory on July 26, 2006

SOHO IMAGES: 

SOHO IMAGES Solar and Heliospheric Observatory (SOHO) has an Extreme ultraviolet Imaging Telescope (EIT) that images the solar atmosphere at several wavelengths, and therefore, shows solar material at different temperatures. In the images taken at 304 Angstroms the bright material is at 60,000 to 80,000 degrees Kelvin. In those taken at 171, at 1 million degrees. 195 Angstrom images correspond to about 1.5 million Kelvin. 284 Angstrom, to 2 million degrees. The hotter the temperature, the higher you look in the solar atmosphere. SOHO EIT 284 image taken July 26, 2006 Srt raster map

Image of the Sun On July 28, 2006: 

Image of the Sun On July 28, 2006 SOHO EIT 284 image 7.28.06

Data From the Small Radio Telescope: 

Data From the Small Radio Telescope

Data From the Small Radio Telescope: 

Data From the Small Radio Telescope

Information from SOHO: 

Information from SOHO Over the past few weeks (date July 21, 2006) this extreme ultraviolet observing instrument on SOHO has witnessed at least four events where pieces of the Sun have blasted off into space. In most instances these are evidence of coronal mass ejections, solar eruptions that occur fairly frequently. Magnetic tensions above active regions strain and break apart, propelling solar particles into space at millions of miles per hour. The first event on June 26th appears to have been triggered by the collapse of a solar prominence suspended by magnetic forces above the Sun. While these clouds of particles are large, they hardly diminish the bulk of the Sun at all. Don't worry: there's plenty left for billions of years to come.

Conclusions: 

Conclusions The raster map is a contour map of the energy output of the sun. Although the raster images were similar on different days, closer examination of the raw data showed a difference of two to three times the magnitude of the energy measured. This could be a calibration error of the small radio telescope. The data was rescaled to account for the possible calibration error. When the data was rescaled, there was not much difference in the radio telescope measurements over the three days.

Conclusions: 

Conclusions When comparing the radio telescope image to images made in different wavelengths, UV and optical, it is possible that the solar sunspot and flares shown on the UV correspond to the irregular shape of the raster map. However, more extensive data collection would be needed to obtain baseline data for the sun and insure accurate calibration of the small radio telescope.

References: 

References National Radio Astronomy Observatory. August 6, 2004. http://www.nrao.edu/whatisra/FAQ.shtml. July 26, 2006 Sky and Telescope. www.skyandtelescope.com. July 24, 2006. Hubble. http://hubblesite.org/ July 27, 2006. Nasa Astronomical Data Center. http://adc.gsfc.nasa.gov/ July 25, 2006 National Optical Astronomy Observatories. National Solar Observatory. http://www.nso.edu/ July 27, 2006. SOHO. Solar and Heliospheric Observatory. July 28, 2006. http://sohowww.nascom.nasa.gov/ downloaded July 24-27, 2006.

References: 

References And of course….. Thank you Lisa Young and Robyn Harrison for all your kind and informative help!