Question: What radio telescope observatory informally as "The Dish" discovered PSR J0737−3039A and PSR J0737−3039B?
Context: The Algonquin 46m radio telescope (ARO) is a radio telescope at the Algonquin Radio Observatory, Canada.  This radio telescope is historically famous for taking part in the first successful very long baseline interferometry experiment in the 1960s, where it was experimentally arrayed with the 26-metre Telescope at the Dominion Radio Astrophysical Observatory near Penticton, British Columbia. PSR B1620-26 b is an extrasolar planet located approximately 12,400 light-years away from Earth in the constellation of Scorpius.  It bears the unofficial nicknames "Methuselah" and "the Genesis planet" due to its extreme age and a few popular sources refer to this object as "PSR B1620-26 c" (see below for discussion).  The planet is in a circumbinary orbit around the two stars of PSR B1620-26 (which are a pulsar (PSR B1620-26 A) and a white dwarf (WD B1620-26)) and is the first circumbinary planet ever confirmed.  It is also the first planet found in a globular cluster.  The planet is one of the oldest known extrasolar planets, believed to be about 12.7 billion years old. SGR J1745−2900 or PSR J1745-2900 is the first discovered magnetar, orbiting a black hole in the Sagittarius A* system.  The magnetar was discovered in 2013 using the Effelsberg 100-m Radio Telescope, the Nancay Decimetric Radio Telescope, and the Jodrell Bank Lovell Telescope.  The magnetar has a period of 3.76 s and a magnetic field of ∼ 10 G (10 T). PSR J1614–2230 is a neutron star in a binary system with a white dwarf.  It was discovered in 2006 with the Parkes telescope in a survey of unidentified gamma ray sources in the Energetic Gamma Ray Experiment Telescope catalog.  PSR J1614–2230 is a millisecond pulsar, a type of neutron star, that spins on its axis roughly 317 times per second, corresponding to a period of 3.15 milliseconds.  Like all pulsars, it emits radiation in a beam, similar to a lighthouse.  Emission from PSR J1614–2230 is observed as pulses at the spin period of PSR J1614–2230.  The pulsed nature of its emission allows for the arrival of individual pulses to be timed.  By measuring the arrival time of pulses, astronomers observed the delay of pulse arrivals from PSR J1614–2230 when it was passing behind its companion from the vantage point of Earth.  By measuring this delay, known as the Shapiro delay, astronomers determined the mass of PSR J1614–2230 and its companion.  The team performing the observations found that the mass of PSR J1614–2230 is M .  This mass made PSR J1614–2230 the most massive known neutron star at the time of discovery, and rules out many neutron star equations of state that include exotic matter such as hyperons and kaon condensates. Reber Radio Telescope is a parabolic radio telescope built by astronomer Grote Reber in his back yard in Illinois in 1937, implementing an earlier proposal of Karl Jansky, the discoverer (1931) of radio waves emanating from the Milky Way.  It was the second radio telescope ever built (after Jansky's dipole array), and the first parabolic radio telescope, serving as a prototype for the first large dish radio telescopes such as the Green Bank Telescope and Lovell Telescope constructed after World War 2.  Made of sheet metal with a 31.4 foot (9 meter) aperture and 20 foot (6 meter) focal length, it was the largest parabolic dish in existence at the time.  Reber was the world's only radio astronomer at the time, and his construction of the telescope and the sky surveys he did with it helped found the field of radio astronomy, revealing radio sources such as Cassiopeia A and Cygnus X-1 for the first time. PSR J0737−3039 is the only known double pulsar.  It consists of two neutron stars emitting electromagnetic waves in the radio wavelength in a relativistic binary system.  The two pulsars are known as PSR J0737−3039A and PSR J0737−3039B.  It was discovered in 2003 at Australia's Parkes Observatory by an international team led by the radio astronomer Marta Burgay during a high-latitude pulsar survey. PSR B1937+21 is a pulsar located in the constellation Vulpecula a few degrees in the sky away from the first discovered pulsar, PSR B1919+21.  The name PSR B1937+21 is derived from the word "pulsar" and the declination and right ascension at which it is located, with the "B" indicating that the coordinates are for the 1950.0 epoch.  PSR B1937+21 was discovered in 1982 by Don Backer, Shri Kulkarni, Carl Heiles, Michael Davis, and Miller Goss. PSR J1311–3430 is a pulsar with a spin period of 2.5 milliseconds.  It is the first millisecond pulsar found via gamma-ray pulsations.  The source was originally identified by the Energetic Gamma Ray Experiment Telescope as a bright gamma ray source, but was not recognized as a pulsar until observations with the Fermi Gamma-ray Space Telescope discovered pulsed gamma ray emission.  The pulsar has a helium-dominated companion much less massive than itself, and the two are in an orbit with a period of 93.8 minutes.  The system is explained by a model where mass from the low mass companion was transferred on to the pulsar, increasing the mass of the pulsar and decreasing its period.  These systems are known as Black Widow Pulsars, named after the original such system discovered, PSR B1957+20, and may eventually lead to the companion being completely vaporized.  Among systems like these, the orbital period of PSR J1311–3430 is the shortest ever found.  Spectroscopic observations of the companion suggest that the mass of the pulsar is 2.7 formula_1 (solar masses).  Though there is considerable uncertainty in this estimate, the minimum mass for the pulsar that the authors find adequately fits the data is 2.15 formula_1, which is still more massive than PSR J1614–2230, the previous record holder for most massive known pulsar. The Parkes Observatory (also known informally as "The Dish") is a radio telescope observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia.  It was one of several radio antennas used to receive live, televised images of the Apollo 11 moon landing on 20 July 1969.  Its scientific contributions over the decades led the ABC to describe it as "the most successful scientific instrument ever built in Australia" after 50 years of operation. PSR B1913+16 (also known as PSR J1915+1606, PSR 1913+16, and the Hulse–Taylor binary after its discoverers) is a pulsar (a radiating neutron star) which together with another neutron star is in orbit around a common center of mass, thus forming a binary star system.  PSR 1913+16 was the first binary pulsar to be discovered.  It was discovered by Russell Alan Hulse and Joseph Hooton Taylor, Jr., of the University of Massachusetts Amherst in 1974.  Their discovery of the system and analysis of it earned them the 1993 Nobel Prize in Physics "for the discovery of a new type of pulsar, a discovery that has opened up new possibilities for the study of gravitation."
Answer: Parkes Observatory