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Geminga
Geminga is a gamma ray and x-ray pulsar source thought to be a neutron star approximately 250 parsecs (around 800 light-years) from the Sun in the constellation Gemini. Its name, attributed by its discoverer Giovanni Bignami, is both a contraction of ''Gemini gamma-ray source'', and a transcription of the words ''ghè minga'' (), meaning "it's not there" in the Milanese dialect of Lombard. The name was approved by the International Astronomic Union on 4 April 2022. Pulsar The nature of Geminga was quite unknown for 20 years after its discovery by NASA's Second Small Astronomy Satellite (SAS-2). Finally, in March 1991 the ROSAT satellite detected a periodicity of 0.237 seconds in soft x-ray emission. Thus, it is supposed that Geminga is a sort of neutron star: the decaying core of a massive star that exploded as a supernova about 300,000 years ago. It was once thought that this nearby explosion was responsible for the low density of the interstella ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geminga By Chandra And Spitzer
Geminga is a gamma ray and x-ray pulsar source thought to be a neutron star approximately 250 parsecs (around 800 light-years) from the Sun in the constellation Gemini (constellation), Gemini. Its name, attributed by its discoverer Giovanni Bignami, is both a contraction of ''Gemini gamma-ray source'', and a transcription of the words ''ghè minga'' (), meaning "it's not there" in the Milanese dialect of Lombard language, Lombard. The name was approved by the International Astronomical Union, International Astronomic Union on 4 April 2022. Pulsar The nature of Geminga was quite unknown for 20 years after its discovery by NASA's Second Small Astronomy Satellite (SAS-2). Finally, in March 1991 the ROSAT satellite detected a Frequency, periodicity of 0.237 seconds in X-ray emission spectroscopy, soft x-ray emission. Thus, it is supposed that Geminga is a sort of neutron star: the decaying core of a massive star that exploded as a supernova about 300,000 y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Second Small Astronomy Satellite
The Small Astronomy Satellite 2, also known also as SAS-2, SAS B or Explorer 48, was a NASA gamma ray telescope. It was launched on 15 November 1972 into the low Earth orbit with a periapsis of 443 km and an apoapsis of 632 km. It completed its observations on 8 June 1973. Mission SAS 2 was the second in the series of small spacecraft designed to extend the astronomical studies in the X-ray, gamma-ray, ultraviolet, visible, and infrared regions. The primary objective of the SAS-B was to measure the spatial and energy distribution of primary galactic and extragalactic gamma radiation with energies between 20 and 300 MeV. The instrumentation consisted principally of a guard scintillation detector, an upper and a lower spark chamber, and a charged particle telescope. Launch The spacecraft was launched on 15 November 1972 into an initial orbit of about of apogee, of perigee, 1.90° of orbital inclination, with an orbital period of 95.40 minutes. from the San Marco pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giovanni Bignami
Giovanni Fabrizio Bignami (10 April 1944 – 24 May 2017) was an Italian physicist. From March 2007 until August 2008, he was Chairman of the Italian Space Agency. Between 2010 and 2014, he was the first Italian to chair the Committee on Space Research (COSPAR), and from 2011 until 2015, he was President of INAF. He was also the chairman of the SKA project. He was married to fellow Italian astrophysicist Patrizia A. Caraveo. Career Bignami graduated from the University of Milan in 1968 with a degree in physics. From 1988 to 1997, he was the Principal Investigator for the European Space Agency's XMM-Newton mission, and was a professor of astronomy and astrophysics at the IUSS Pavia in Pavia. He is most known for his discovery of the neutron star Geminga. From 2004 to 2007, he was President of the Space Science Advisory Committee (SSAC) of the European Space Agency, and from 2007 to 2008, he was Chairman of the Italian Space Agency. Bignami stood as a Democratic Party candidate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
