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3C 273 (HIP 60936)
Thomas Dykstra

3C 273

Circled in red above is 3C 273; it looks like an ordinary star but is actually a quasi-stelar radio source or "quasar." Quasars are found within some galactic nuclei and are sometimes called active galactic nuclei (AGN). They are known to be the most luminous objects found in the universe. Ironically enough these highly luminous objects are actually supermassive black holes. Some objects to mention in the picture above. The bright star near the bottom left is Tycho 282:227 at an appherant magnitude of 10.19. The star circled in green is GSC 282:115 at an appherant magnitude of 12.9. The two stars next to 3C 273 are GSC 282:337 and GSC 282:1090 of magnitudes 13.85 and 14.18 as seen from higher to lower. For a better look, below is an image from the Hubble Space Telescope of the qausar up close, along with an image of the spherical galaxy it is housed in.

3C 273 can be found near the Virgo constelation in our sky. It was first found in 1959 by the Cambridge Radio Survey and later identified as a quasar in 1963 by Maarten Schmidt. With an appharent magnitude of 12.8 it can be seen with an amateur telescope. The ramarkable fact about its luminance is that it can be viewed so easily despite being roughly 2 billion light-years away. To give a little perspective, if 3C 273 was at a distance of 30 light-years, about seven times father than the nearest star to us. It would shine in the sky as brightly as our sun, which is 0.00001581 light-years away from us.

The basic structure of a quasar or supermassive black hole consists fo a singularity, acretion disc, and radiojet. The singularity is the physical description of a black hole in which matter is compressed to an infinitesmal speck, creating a gravitational field strong enough to capture light. The acretion disk is light and matter that rotates around the singularity outside of its event horizon, matter and light in the acretion disk are able to scatter off and escape its gravity. Radio jets are the most fascinating portion of a quasar. Radio jets are high speed emmisions of particles traveling near the speed of light. It is still unknown what process creates these jets. An image of a jet coming from 3C 273 can be seen below.

Anouther unique behavior of quasars is that they oscilate in the visual and radio spectrum. By gathering luminosity data every few minutes and using GSC 282:115, circled in green in the main image, as a baseline the graphs below were gathered. The first graph is for March 21 the second is a larger collection of data from March 30. In the first graph the oscilations showed an upward luminosity change of 1.6% and a downward change of 6.4%. The second graph showed a luminosity change upwards of 5.8% and downwards of 2.6%.

To gather the data used for 3C 273 the Rehoboth New Mexico telescope with a viewing window of 15 x 10 arcminutes was used. It didn't allow for enough resolution to view the radiojets. However, it was enough to gather light data in the blue, green, red, and clear spectrums. Once gathered the data was corrected for error through a program called Maxim. Bias, Dark, and Flat frames were taken before every night of images. These correction images were used as baselines for each night to clear up the images.


Chandra X-Ray Observatory. <>.

ESA/Hubble. "Hubble Space Telescope." <>.

Julian Date Converter. <>.

Karge, Stefan. "Frankfurt Quasar Monitoring." <>.

Phillips Colby. "Distances of the Planets From the Sun in Light Years." <>.

Software Bisque. "TheSkyXProfessional"


Right Ascension (J2000) 12h 29m 06.7s
Declination (J2000) +02d 03m 08.6s
Filters used B (Blue), C (Clear), R (Red), V (Green)
Exposure time per filter B and V (5m), R (3m), and C (1m);
Image dimension 654x552 pixels; 14.4x12.1 arcminutes
Dates observed March 16-30, 2017



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