Designations: IRAS F08279+5255; QSO B0827+5255; KODIAQ J083141+524517; LQAC 127+052 013; PS-ELQS J083141.69+524517.5
Constellation: Lynx
Type: Gravitationally lensed Quasar
RA: 8:31:41.7
DEC: +52°45'18"
Mag (v): ~16.5
How far can you see? I have always been fascinated by the immense distances in the Universe. Quasars are the most remote objects that can be seen visually. Most deep-sky observers have seen 3C 273 in Virgo, located about 2.4 billion light-years away.
Gravitational lenses are a way for nature to help us see much further. In 1998, the Automatic Plate Measuring (APM) Facility survey was searching for carbon stars. One of the red objects was discovered to have an extreme redshift, z = 3.911, and was designated as the broad absorption line quasar APM 08279+5255. It turned out to be a giant elliptical galaxy with an active galactic nucleus at its core. It is also classified as an ultra-luminous infrared galaxy (ULIRG). The redshift implied that the light had travelled for 12.05 billion years! The corresponding ”co-moving radial distance” is about 23.6 billion light-years (using cosmological standard parameters). This is pre-solar light, meaning the light is 2.5 times older than our solar system!
The Hubble Space Telescope revealed that a massive intervening galaxy distorts the quasar's light into three images, an odd number which is extremely rare. The two brightest components are separated by only 0.4 arc-seconds. The facts about APM 08279+5255 are mind-boggling: the supermassive central black hole has a mass of 23 billion Suns and more than 100 trillion times the amount of water found in Earth's oceans is revolving around the black hole. Its luminosity is up to 5 million billion Suns making it one of the most luminous known objects in the Universe.
On March 28, 2014, I was using our local astrononomy club's, VARF, 16-inch Optimized Dall-Kirkham telescope. The Urania Observatory is located in the northern outskirts of Västerås, Sweden, with a population of 160,000. The sky is not very dark, with an SQM-L reading of about 20.7 at best. One of my targets that evening was APM 08279+5255. With 544x magnification, I could glimpse a very faint star in the correct position. I also managed to observe it at 302x magnification. It was a challenging object, but the dark interior of the dome and the altitude of 75° helped me with the observation.
The Finnish amateur astronomer Iiro Sairanen managed to observe APM 08279+5255 with his 18-inch reflector and 309 power as early as January 2006.
11 arc-minutes SE of APM 08279+5255, I spotted the galaxy CGCG 263-43 (Markarian 91). Its magnitude is 14.6 (p) and diameter of 0.8'. I found it rather faint and very small.
Another galaxy in the field was UGC 4461, with a magnitude of 13.5 and a size of 1.7'x0.5'. At 300x magnification it appeared faint, much elongated NE-SW and diffuse.
APM 08279+5255.jpg
The quasar APM 08279+5255 is centred in the square, CGCG 263-43 below the centre and UGC 4461 in the lower-left corner. (© https://www.wikisky.org )
Just half an hour later, I hunted down another extremely distant object, the gravitationally lensed Twin Quasar QSO 0957+561 in Ursa Major. The faint image was elongated in the N-S direction, but I could not fully distinguish its two components.
I recently read some exciting news: in February 2024, the quasar QSO J0529-4351 in the southern constellation Pictor was found to be even more distant than APM 08279+5255, at a redshift of z = 3.961! Some amateurs have already observed QSO J0529-4351 since it appears to be slightly brighter at magnitude 16.
So next time you are out observing, try catching some pre-solar photons! And finally:
Give it a go and let us know!
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Timo Karhula
Virsbo, Sweden
(my most used instruments)
12" f/5 Dob
10" f/5 Dob (in Geraldton, Western Australia)
25x100 binoculars
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Originally Posted by timokarhula
