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         Hipparchus Of Rhodes:     more detail
  1. Ancient Rhodian Scientists: Hipparchus, Posidonius, Geminus, Dinocrates, Attalus of Rhodes

41. Mappa.Mundi Magazine - Locus - Meridian
In the second century BC hipparchus of rhodes proposed that all distances bemeasured from a meridian running through the island of Rhodes,
http://mappa.mundi.net/locus/locus_015/
Stephanie Faul is director of public relations for the AAA Foundation for Traffic Safety. A long-time writer and editor, she has been a frequent contributor to on-line and old-line media.
Locus is a series about words about places and how language, culture and society have created and used these words down through the ages.
Previous Issues
Links Relating
to this edition
Greenwich Meridian on-line.
On the Line
links people in the eight meridian-line countries.
Latitude and Longitude
on Compton's Encyclopedia Online.
"Tracing the Greenwich Meridian"
Ordnance Survey, Britain's national mapping agency.
"Hipparchus of Rhodes"
from the School of Mathematics and Statistics University of St Andrews, Scotland.
"Ptolemy"
from the School of Mathematics and Statistics University of St Andrews, Scotland.
"Ptolemy's Geography"
from the EXPO John Flamsteed George Airy "Suffolk's own Time Lord" By Naomi Kilby. The Airy Transit Circle Burt's Solar Compass used in iron mines in Michigan. By Stephanie Faul

42. Astronomy Links - Early Astronomy
hipparchus of rhodes St Andrew s University page; Cornell University page.Ptolemy, Claudius Galileo Project page; St Andrew s University page; seds page.
http://www.olemiss.edu/courses/astr104/Topics/Ancient-L.html
University of Mississippi Astronomy Main Lectures News Resources ... Lab Early Astronomy - Until the XV Century
(See also Renaissance astronomy and modern History of astronomy) History of Astronomy
  • General: Windows to the Universe page
  • Lecture Notes: Jose Wudka (ucr.edu) history of cosmology notes
Archaeoastronomy
  • In General: Center for Archaeoastronomy site ; Windows to the Universe page
  • Megaliths: Stone Pages site
Antiquity and Topics
  • Aristarchus of Samos: St Andrew's University page ; K Riley's page at Tufts.
  • Aristotle: St Andrew's University page ; 2002 Rowan-Robinson article
  • Eratosthenes of Cyrene: St Andrew's University page
  • Hipparchus of Rhodes: St Andrew's University page ; Cornell University page
  • Ptolemy, Claudius: Galileo Project page ; St Andrew's University page ; seds page
  • Mythology: M.F. Lindemans' pantheon.org Encyclopedia Mythica site
  • The Sun: NASA sponsored project on The Sun in Time
Medieval Astronomy
  • Giordano Bruno: The Radical Academy page
  • Nicholas of Cusa: St-Andrews University page
Astronomy in Different Cultures
  • Arabs: A. Zahoor's

43. Astronomy Lecture Notes - Early History
hipparchus of rhodes (190120 BC) Wrote a star catalog in which he introducedthe magnitude system also calculated the length of the year and discovered
http://www.olemiss.edu/courses/astr103/Topics-Introduction/Ancient-N.html
Early History
of Astronomy
(External Links
page Prehistoric Period - Early Sites and Archeoastronomy
  • Importance of astronomy: Season changes, marked by equinoxes and solstices (celebrated with decorated trees, Yule logs, mistletoe and communal celebrations, for example), were important dates for agriculture and hunting; Motion of the Sun, the Moon and fixed stars also used to keep track of the time of day, for orientation, and later navigation needs.
  • Earliest evidence: Cave paintings like Lascaux (16,000 yr ago) and others (stars, 5000-yr old map of the Moon).
  • Earliest structures: Many examples with aligned markers to keep track of time of year, like Nabta (5000-3000 BC), Stonehenge (2800-1100 BC), Seahenge (2050 BC).
  • America:
  • Planets: In the bronze age around 3000 BC, the planets were known out to Saturn. Their wandering motion made them less useful for orientation, but they were used for calendars and astrology.
[More speculative: Did catastrophic events like comet impacts occur around 3000-2000 BC and contribute to the demise of ancient civilizations?]

44. Astronomy@Kirkwood IC: Supplemental Notes--Astronomy Of Ancient Greece
Hipparchus hipparchus of rhodes (190–120 BC) observed a nova stella (today wewould call it a supernova) in 134 BC and this strange, new object in the
http://www.avalon.net/~bstuder/added_notes1.html
Home Contact Site Map Renaissance Astronomy ...
The Birth of Physics
Exam I Review Sheet Sample Problems Problem Solutions Practice Exam ... Exam Solutions Exam II Review Sheet Sample Problems Problem Solutions Practice Exam ... Exam Solutions Final Exam Review Notes Sample Problems Problem Solutions Heaven's net cast wide. Though its meshes are coarse, nothing slips through.
Supplemental notes: Astronomy of Ancient Greece
The following notes are excerpted from the class text, Journey to the Cosmic Frontier by John D. Fix, and Archives of the Universe by Marcia Bartusiak.
Thales Anaximander and possibly Pythagoras . None of his writings survive.
Anaximander of Miletus, a younger contemporary of Thales, believed the earth floated in nothingness (since it did not appear to move in one direction or another). He also believed the earth to be cylindrical in shape.
Pythagoras Eudoxus of Cnidus (c. 408 – 347 B.C.) expanded upon the Pythagoras' idea of perfect circles and accepted Plato's invention that the planets move around Earth on crystalline spheres (the spheres had to be perfectly transparent to see the more distant objects). From this, Eudoxus developed a system of 27 concentric spheres centered on Earth. The outer sphere contained the fixed stars while each "wandering star", or planet, required four spheres. The Sun and Moon each required three spheres.

45. So What Sign Are You Anyway? Tropical Vs. Sidereal Astrology
It was the Greek astronomer, hipparchus of rhodes, who first officially discoveredthat the Sun was in a slightly earlier position at the time of the Spring
http://www.mr-wizard.com/whatsign.html
Articles: Uranus in Pisces:
The Dawn of

the New Age?
Indigo Children: ...
The Color of the Future.
So What Sign Are
You Anyway?
Tropical vs. Sidereal Astrology AFT Home So What Sign are you Anyway?
Tropical vs. Sidereal Astrology

by: Dante DiBenevento

Some people (including die-hard astrology fans) will be absolutely amazed to learn that the constellation they believe marks the sign of their birth is not the current constellation that is behind the sun on their birth-date. The universe is an ever-changing place and like the Earth around the Sun, it too is revolving and moving (ever so slowly).
From time unmemorable, man has always had a fascination with the heavens above.
Early astronomers noticed that some of these constellations appeared and disappeared throughout the course of the year. Amongst these constellations, there was a group that seemed to move in line with each other along the Plane of the Ecliptic (which is the path in the sky defined by the apparent motion of the Sun). To the ancient western astronomers, there were twelve specific constellations that appeared to behave in this fashion. They were named and categorized by their identifiable shapes and given origins based on mythological legends. They are as we know them today: So how does this affect astrology?

46. Appendix 1
A generation later, Greek astronomer hipparchus of rhodes (c190125) compiledthe first star catalog of about 850 stars. His follower, Ptolemy of Alexandria
http://www.visualstatistics.net/web Visual Statistics/Visual Statistics Multimed
Appendix 1 Mathematical Foundations of Visual Statistics
The mathematics pertains to numbers, space, time, and logic. The number sense probably developed from the ordinal concepts of greater than, equal, and less than. Combined with the time sense that some events precede and some events follow the others, numbers were arranged along a scale where some numbers precede and some numbers follow the others.
Pythagoras
During the time of Pythagoras, about 500 B.C., it was observed that certain numbers, called the Pythagorean triplets, describe the right triangles. For example, the original Pythagorean triplets 3, 4, and 5, associated with the height, the width, and the hypotenuse of a right triangle illustrate the Pythagorean theorem, that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides. This was one of the first connections made between numbers and geometrical properties of objects and thus the foundation of the visual statistics was laid. The Pythagoreans also noticed that vibrating strings produce harmonious tones when the ratios of the lengths of the strings are whole numbers. They attempted to build a geometric model of these ratia in the sky where the motions of planets, within the celestial spheres were thought to produce a harmony called the music of the spheres.

47. GEOG 482 Project 1 Sample Report
Traced back to 2nd Century hipparchus of rhodes (Robinson et al) it has historicallybeen used for navigation of ships. Consisting of east/west location
http://www.personal.psu.edu/users/b/w/bwo105/P01_Report.html

48. A Potted History Of Computers - The Birth
It is worth noting, however, that the man who invented trigonometry and firstscientifically catalogued the stars positions was hipparchus of rhodes.
http://www.hodgy.net/computer_history/page_1/page_1a.htm
T he birth of computers - life Jim but not as we know it!
Abacus
Egyptians and Romans 1st Century BC 2nd Century ... Marconi
Abacus
An Abacus is a simple device for performing arithmetic calculations and therefore is the ancestor of the modern calculating machine and computer. It is basically a calculating device, probably of Babylonian origin, sometime between 1,000 BC and 500 BC, (although some pundits are of the opinion that it was actually invented by the Chinese) that was long important in commerce.
The word abacus comes to us by way of Latin as a mutation of the Greek word abax . In turn, the Greeks may have adopted the Phoenician word abak , meaning "sand", although some authorities lean toward the Hebrew word abhaq , meaning "dust."
Irrespective of the source, the original concept referred to a flat stone covered with sand (or dust) into which numeric symbols were drawn. The first abacus was almost certainly based on such a stone, with pebbles being placed on lines drawn in the sand. Over time the stone was replaced by a wooden frame supporting thin sticks, braided hair, or leather thongs, onto which clay beads or pebbles with holes were threaded.
A variety of different types of abacus were developed, but the most popular became those based on the bi-quinary system, which utilizes a combination of two bases (base-2 and base-5) to represent decimal numbers. Although the abacus does not qualify as a mechanical calculator, it certainly stands proud as one of first mechanical aids to calculation.

49. Kenneth Bowser - Western Sidereal Astrology : Frequently Asked Questions # Ken B
world until the Greeks decided to use the equinoxes and solstices to reckoncelestial positions, probably around the time of hipparchus of rhodes.
http://www.westernsiderealastrology.com/faqs/faqs.asp
Frequently Asked Questions
  • What is western sidereal astrology?
    Sidereal astrology, from the Latin, sidus , (star) or sidereus
  • How did western sidereal astrology come to the West?
    American Astrology magazine from 1953 until his death in 1970 that influenced a new generation of astrologers. He also wrote several books on the topic including Astrological Origins Zodiacs Old and New and Symbolism of the Constellations
  • How can I find out more about Cyril Fagan's work?
    A brief biography of Cyril Fagan is available on this site. We have also included several excerpts of Fagan's early articles from Amercian Astrology magazine. More excerpts will be posted in the future. Fagan's books Zodiacs Old and New and Symbolism of the Constellations are out of print but can be found via a web search. Astrological Origins can be ordered on Amazon.com.
  • What is the difference between tropical and sidereal astrology?
  • How does the actual practice of western sidereal astrology differ from tropical astrology?
  • 50. Astronomy 9 (Spring 2000): Handout 10
    hipparchus of rhodes (190120 BC). Great Greek astronomer; Synthesized Babylonianand Greek data with new Greek geometrical models from Appollonius
    http://jonathanbaker.org/courses/ay9/week4/handout10/
    Up: Astronomy 9 Lecture Notes
    A STRONOMY 9: H ISTORY OF C OSMOLOGY
    Handout #10
    J. E. Baker
    UC Berkeley, Spring 2000 Cosmology in Ancient Greece: Aristotle and Greek Astronomy
    Aristotle (384-322 BC)
    • Student of Plato's Academy
    • Founded Lyceum
    • Worked in almost every field of known science and philosophy!
    • Profound influence on development of Western science
    • Every effect must have a cause
    • Important innovation: universe can be described by natural laws inferred by rational thought
    • Aristotle's physics: mostly quite wrong, but strong common-sense appeal
      • Founded science of mechanics (physics of motion)
      • Developed the idea of ``force'', impetus theory of motion (wrong, but widely held even today!)
      • Thought force was required to keep Earthly objects in motion (didn't fully understand inertia
    • Aristotle applies his physics to the cosmos
      • Basic Earthly elements: air, earth, fire, water
      • Terrestrial and celestial physics are very different!
      • Two types of ``natural'' motion
        (a)
        Earth: linear, straight-line, finite motion (air and fire go up, water and earth go down)
        (b)
        Heavens: perfect, eternal, circular motion

    51. ARMILLARY SPHERES - Beautiful Recreations Of Antique Scientific Instruments
    and hipparchus of rhodes (150125BD) determined distance from the Earth tothe Sun and produced a complete star catalogue for his latitude) in practice
    http://www.sunscience.co.uk/armillary.html
    Home Armillary Astrolabe Sundials ... Contact
    'Armillary spheres were originally commisioned by the rich and learned aristocracy who used them to demonstrate the basic principles of astronomy and horology.'
    As well as being a beautiful objects in themselves, our armillary spheres are fully engraved to enabling them to be used as they were in the past. We believe that we produce the most authentic armillary spheres in the world. Our extensive research and attention to detail, ensures that you will be buying an armillary sphere which accurately reproduces the form and artistry of these highly sought after antiques. It is of course possible to buy much cheaper ornamental armillary spheres, but these should not be compared with ours. An armillary sphere from Sun Science provides a point of interest for your garden or a sense of history and elegance for your home.

    52. Science Timeline
    hipparchus of rhodes, 134 bce. Hippocrates of Chios, 430 bce. Hippocrates of Cos,400 bce, 1185. His, Wilhelm, 1887, early decades 20th century
    http://www.sciencetimeline.net/siteindex_h.htm
    use checkboxes to select items you wish to download
    Select Index Letter:
    a
    b c d ... w-x-y-z
    Haber, Edgar, 1962 Haber, Fritz,1909, 1915 Habermas, Jurgen, 1968 hackers, 1959 Haeckel, Ernst Heinrich, 1859, 1866, 1940 Hahn, Otto, 1938 Haken, Wolfgang, 1976 Haldane, John Burdon Sanderson, 1924, 1926, 1929, 1932, 1937, 1941 Hale, George Ellery, 1908, 1949 Hales, Stephen, 1727, 1733 Haley, Jay, 1952 Hall, Benjamin D., 1961 Hall, Chester More, 1733 Hall, Edwin Herbert, 1879, 1980 Hall, Howard, 1999 Hall, James, 1795 Hall, Jeffrey C., 1984, 1986, 1991 Hall, John L., 1989 Hall, Marshall, 1833 Halley, Edmund, 1678, 1693, 1705, 1718, 1758, 1759, 1835 hallucinagenic mushroom, 7000 bce Halm, Jacob, 1911 Hamburger, Viktor, 1975 Hamer, Dean H., 1993

    53. Epicycle(1): Draws Point Moving Around Circle ... - Linux Man Page
    The geometry of epicycles was perfected by hipparchus of rhodes at some timearound 125 BC, 185 years after the birth of Aristarchus of Samos, the inventor
    http://www.die.net/doc/linux/man/man1/epicycle.1.html
    epicycle(1) - Linux man page
    NAME
    epicycle - draws a point moving around a circle which moves around a cicle which...
    SYNOPSIS
    epicycle [-display host:display.screen ] [-root] [-window] [-mono] [-install] [-noinstall] [-visual viz ] [-colors N ] [-foreground name ] [-color-shift N ] [-delay microseconds ] [-holdtime seconds ] [-linewidth N N N number number ] [-harmonics N ] [-timestep number probability number number
    DESCRIPTION
    The epicycle program draws the path traced out by a point on the edge of a circle. That circle rotates around a point on the rim of another circle, and so on, several times. The random curves produced can be simple or complex, convex or concave, but they are always closed curves (they never go in indefinitely). You can configure both the way the curves are drawn and the way in which the random sequence of circles is generated, either with command-line options or X resources.
    OPTIONS
    -display host:display.screen
    Specifies which X display we should use (see the section DISPLAY NAMES in X (1) for more information about this option).
    -root
    Draw on the root window.

    54. Compositions Successfully Submitted To The Collegio Romano
    longitude by virtue of the observation of the eclipses of the Moon, as proposedby the learned hipparchus of rhodes, should I trust be readily apparent.
    http://www.vaticanengarde.com/BGprinmeth.htm
    On the principles and methodology of the measurement of the Earth and the Heavens
    by Bartolomeo Gagliardi
    In writing this work it is my most earnest hope that it will prove of some utility to mathematicians, navigators and those who seek to further our knowledge of this world and its many distant places. All herein is dedicated to the greater glory of God, from whom all knowledge does come and to which all in turn shall return. That the world is a sphere is well known, and recorded in the Geographia of Ptolemy so recently translated to the elucidation of all by Martin Waldseemuller, whose essays on perspective have helped inspire this work. Magister Waldseemuller writes eloquently of the difficulties in establishing perspective and in measuring it accurately in the absence of full observatory and globe. It is to that problem I now turn myself. Where it is desired that an accurate map be prepared many things are required. Of these, among the more important is the calculation of longitude and one's position upon the globe. That longitude is measurable with recourse to but the simpler instruments I shall now seek to demonstrate. The Moon circumnavigates the Earth according to a fixed procedure, at any time its declination being a matter of calculation and observation. Further, the Moon in its passages retains a fixed distance from the Earth. Behind its motion it may be observed that the stars themselves appear fixed, although this be not so, for the Moon's transit across the sky is far greater in rapidity than their own. Indeed, in but one hour the Moon moves through the entirety of its diameter.

    55. Conservation Treatment Awards West Region
    The six scientists depicted are hipparchus of rhodes, Copernicus, Kepler, Galileo,Isaac Newton, and William Herschel. Six different artists—Roger Noble
    http://www.heritagepreservation.org/PROGRAMS/SOS/CTA/West.htm
    Conservation Treatment Awards West Region (includes Alaska and Hawaii) Arizona California Hawaii Oregon ... Washington Arizona
    Tucson
    Freeman Pioneer Memorial

    The Freeman Pioneer Memorial California
    Los Angeles
    Astronomer's Monument

    Located at the internationally famous Griffith Observatory, Astronomer's Monument (1934) stands 25 feet tall and includes statues of important scientists in world history. The six scientists depicted are Hipparchus of Rhodes, Copernicus, Kepler, Galileo, Isaac Newton, and William Herschel. Six different artists—Roger Noble Burnham, Djey el Djey, Arnold Forester, Archibald Garner, Gordon Newell, and George Stanley—were hired to sculpt the figures. Stanley also designed the Academy Award or "Oscar." Griffith Observatory and the City of Los Angeles are the owners. The Friends of the Observatory is the applicant. The Hugo Reid Family
    Scottish-born Hugo Reid was one of the first English-speaking immigrants to live in southern California. Elected as a delegate to the California Constitutional Convention, Reid was one of the signatories of the state's first Constitution. Perhaps he is best known for the more than 20 letters he wrote to the LA Star in 1851, which described and thus preserved the beliefs, customs, and traditions of the local Native American tribes. Married to a Native American, he adopted her two children at a time when many other immigrants were marrying into prominent Spanish-speaking families.

    56. H
    hipparchus of rhodes ca. 180 ca. 125 BCE). Born in Greece. His mathematicalcomputations to chart the sun, moon, and stars led to his being named the
    http://www.innvista.com/science/math/mathians/h.htm
    H Home About Us Contact Us Home ... Mathematicians Search innvista.com Our Notice Board
    H
    Thomas Harriot
    • Born in England.
    • He was instrumental in extending and codifying the theory of equations.
    • He was the first to use and to indicate greater than and less than.
    Felix Hausdorff
    • Born in Germany.
    • He developed the branch of mathematics known as topology.
    • He formaulated a maximal principle in general set theory.
    Jacques Herbrand
    • Born in France.
    • He formaulated a theory which established a link between quantification theory and sentential logic.
    Charles Hermite
    • Born in France.
    • He applied elliptic functions to find solutions of the quintic equation and of Lamé's differential equation..
    • He discussed the theory of associated covariants in binary quantics and the theory of ternary quantics
    Heron (Hero of Alexandria) (fl. 62 CE)
    • Born in Egypt.
    • His formula provides the area of a triangle when the lengths of the three sides are known, but the height is not known.
    David Hilbert
    • Born in Prussia.
    • He solved all the known problems of algebraic invariants.
    • He introduced sweepng developments and new areas for research in algebraic topography.

    57. Is The Earth's Climate Changing? - Access To Energy Newsletter Archive
    The earth s axis now points to the North Star, but that is not where it pointedwhen hipparchus of rhodes first noted the wobble in about 120 BC Scientists,
    http://www.accesstoenergy.com/view/atearchive/s76a4558.htm
    Is the earth's climate changing?
    What makes the climate is the sun, of course the nuclear reactor that provides 98% of the earth's heat (the remaining 2% are geothermal and also nuclear: radioactive decay in the earth's interior). And the sun-earth configuration is subject to certain periodicities. The trivial ones are night and day caused by the earth's rotation, and the yearly seasons encountered as the earth, with its inclined axis, travels round its orbit. But there are other periodicities. A spinning top does not keep its axis in a constant direction; it wobbles. If it had a flashlight built into its axis, it would trace a circle on the ceiling. The earth's axis now points to the North Star, but that is not where it pointed when Hipparchus of Rhodes first noted the wobble in about 120 B.C. Scientists, who do not use words like "wobble" (for everybody understands them), call this motion precession; it takes about 25,700 years to complete one wobble-circle. Actually, it is not pure snobbism that makes scientists eschew such words, for there is a lot of wobbling going on (as can be found under precession and nutation in a good encyclopedia), and the different types need to be distinguished. But it is the basic type of precession (and slight changes in the distance from the sun) that very probably cause the recurrent ice ages. And there is about 9,000 years to go before it gets cold again from that quarter. Another periodicity is that of solar activity, which moves from relative quiescence to high activity in the form of sunspots, flares, protuberances, and other forms of gigantic upheaval, and back again to low activity. The period is not regular, but has an average of 11 years. (These are half-cycles, if you want to quibble; the solar goo in the spots whirls clockwise for 11 years, and reverses for the next half-cycle.)

    58. Stellar
    Greek astronomer hipparchus of rhodes is recognized as being the first person tocatalog the Constellation of RX7. Regretfully the Greeks were unable to
    http://www.q-net.net.au/~orinoco/stellar.html
    Greek astronomer Hipparchus of Rhodes is recognized as being the first person to catalog the Constellation of RX7. Regretfully the Greeks were unable to integrate RX7 into their existing mythology, despite Hipparchus suggesting it was the preferred Chariot of the Gods. Ridiculed, Hipparchus directed his talents to Mediterranean trade and was to later establish the first branch of the Rotary Club. After examining the pictured sky chart, many current owners are disturbed by a significant stellar event originating in the night sky south west of RX7. Star Cluster, Major Service (due at 80 000 light years), is expected to cross RX7 towards the end of this month. With Nebula Minor Service descending behind the southern horizon, owners expect RX7 to remain sky high for some time. Big Bang Theorists now concede it may have just been RX7 back firing on a cold stellar morning. Viewing Tips: Today the casual observer need only stand on the road side after sunset to view the approaching lights of RX7. Back to Home.

    59. JCA: Education: Physics 316 (Lecture 1)
    Early Cosmo Aristotle, Hipparchus Ptolemy The Rise of Reason Beauty.(Timeline for the curious) Early Cosmo hipparchus of rhodes (c.125BCE)
    http://www.jca.umbc.edu/~george/html/courses/2002_phys316/lect1/lect1.html
    [4097] Physics 316: Extragalactic Astronomy and Cosmology (Summary of Lectures)
    Lecture 1
    Summary of Topics covered in this Lecture

    60. JCA: Education: Magnitude System + Dist Modulus
    These are measures of the brightest of an object, and based on the originalclassification scheme used by hipparchus of rhodes who assigned an apparent
    http://www.jca.umbc.edu/~george/html/courses/glossary/magnitude_system.html
    Glossary
    These are measures of the brightest of an object, and based on the original classification scheme used by Hipparchus of Rhodes who assigned an apparent magnitide m = 1 to the brightest stars in the sky (excl the Sun), and an apparent magnitide m = 6 to the faintest stars visible to the naked eye. The scheme has since been formalized on a logarithmic scale such that a difference in apparent magnitude m - m corresponds to a difference is brighness of exactly . ie log (F /F ) = 2 (m - m brighter objects have lower apparent magnitudes The luminosity (assuming isotropic emission) of something a distance r away observed with a flux F is obviously L = 4 pi r F Again for historical reasons, the absolute magnitude is defined as the apparent magnitude the object would have if it were at a distance r = 10 pc more luminous objects have lower absolute magnitudes The relation between an object's apparent magnitude (m) and apparent magnitude (M) is obviously related to its distance in parsecs log (F /F ) = 2 log ( d / 10) so m - M = 5 log (d) - 5 = 5 log (d / 10 pc) This is known as the Distance Modulus

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