X Persei is a high-mass X-ray binary system located in the constellation Perseus, approximately 950 parsecs away. It is catalogued as 4U 0352+309 in the final Uhuru catalog of X-ray objects. The conventional star component of X Persei has been classified either as an O-type giant or a B-type main sequence star. It is a Be star, rotating rapidly, and at times surrounded by a disk of expelled material. This qualifies it as a Gamma Cassiopeiae variable, and the visual range is magnitude 6 - 7. In 1989 and 1990, the spectrum of X Persei changed from a Be star to a normal B class star while it faded significantly. This appears to have been caused by the loss of the excretion disk. The disk has since reformed and shows strong emission lines. The system also contains a neutron star which is a pulsar with an unusually long period of 837 seconds. The pulsar has shown period changes that are associated with mass transfer from the more massive primary star. Between 1973 and 1979 it was seen to increase its rate of spin, associated with a strong x-ray flare and presumed strong mass transfer. Since then the spin has been slowing despite small x-ray flares. The combination of a neutron star and OB emission line star places X Persei in the Be/X-ray binary class of stars. There is a faint optical companion separated by 22.5" which the Catalog of Components of Double and Multiple Stars refers to as X Persei B. It is a background red giant and a candidate long period variable with the variable star designation V397 Persei. (Wikipedia).
Scientific Computing Skills 5. Lecture 24.
UCI Chem 5 Scientific Computing Skills (Fall 2012) Lec 24. Scientific Computing Skills View the complete course: http://ocw.uci.edu/courses/chem_5_scientific_computing_skills.html Instructor: Douglas Tobias, Ph.D. License: Creative Commons BY-NC-SA Terms of Use: http://ocw.uci.edu/info.
From playlist UC Irvine Chemistry 5: Scientific Computing Skills
Virtual Star Party - October 6, 2013
Another wonderful Virtual Star Party, this time with 5 astronomers broadcasting their view of the night sky live. We had amazing views of Saturn, the Ring Nebula, M27, and M17 the Swan Nebula (also known as the Lobster or Horseshoe Nebula). We also caught great views of NGC-896, NGC-869,
From playlist Virtual Star Party
An general explanation of the underactive thyroid.
From playlist For Patients
A-Ha - Take On Me (Vocals Half-Step Out of Key)
My Social Medias, yo (ง ͠° ͟ل͜ ͡°)ง ➤ https://linktr.ee/
From playlist Songs to Torture Undergrads
Mod-01 Lec-05 Error in the Interpolating polynomial
Elementary Numerical Analysis by Prof. Rekha P. Kulkarni,Department of Mathematics,IIT Bombay.For more details on NPTEL visit http://nptel.ac.in
From playlist NPTEL: Elementary Numerical Analysis | CosmoLearning Mathematics
Mod-01 Lec-04 Properties of Divided Difference
Elementary Numerical Analysis by Prof. Rekha P. Kulkarni,Department of Mathematics,IIT Bombay.For more details on NPTEL visit http://nptel.ac.in
From playlist NPTEL: Elementary Numerical Analysis | CosmoLearning Mathematics
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Elementary Numerical Analysis by Prof. Rekha P. Kulkarni,Department of Mathematics,IIT Bombay.For more details on NPTEL visit http://nptel.ac.in
From playlist NPTEL: Elementary Numerical Analysis | CosmoLearning Mathematics
Mod-01 Lec-12 Gauss 2-point Rule: Construction
Elementary Numerical Analysis by Prof. Rekha P. Kulkarni,Department of Mathematics,IIT Bombay.For more details on NPTEL visit http://nptel.ac.in
From playlist NPTEL: Elementary Numerical Analysis | CosmoLearning Mathematics
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From playlist NPTEL: Elementary Numerical Analysis | CosmoLearning Mathematics
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Powered by https://www.numerise.com/ All Core 3 Edexcel past paper questions on rational functions with full worked solutions. www.hegartymaths.com http://www.hegartymaths.com/
From playlist Core 3: Edexcel A-Level Maths Full Course
بسم الله الرحمن الرحيم Hello everyone, this is the video that me and my sister made for 3blue1brown's Summer of Math Exposition contest (SoME1). I hope you learn from it and I hope you enjoy it! Timeline 1:15 Derivatives of sin(x) and cos(x) 5:08 Geometrically proving the quotient rul
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My notes are available at http://asherbroberts.com/ (so you can write along with me). Calculus: Early Transcendentals 8th Edition by James Stewart
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