# translation of kstars_magnitude.po to 
# translation of kstars_magnitude.po to
# translation of kstars_magnitude.po to
# Copyright (C) 2002 Free Software Foundation, Inc.
# Lwandle Mgidlana <lwandle@translate.org.za>, 2002
#
msgid ""
msgstr ""
"Project-Id-Version: kstars_magnitude\n"
"POT-Creation-Date: 2001-02-09 01:25+0100\n"
"PO-Revision-Date: 2002-09-26 12:32+0200\n"
"Last-Translator: Lwandle Mgidlana <lwandle@translate.org.za>\n"
"Language-Team:  <xh@li.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: application/x-xml2pot; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"X-Generator: KBabel 1.0beta2\n"

#: index.docbook:3
#, no-c-format
msgid "<firstname>Girish</firstname> <surname>V</surname>"
msgstr ""

#: index.docbook:7
#, no-c-format
msgid "Magnitude Scale"
msgstr ""

#: index.docbook:8
#, no-c-format
msgid "<para> </para>"
msgstr "<para> </para>"

#: index.docbook:9
#, no-c-format
msgid ""
"2500 years ago, the ancient Greek astronomer Hipparchus classified the "
"brightnesses of visible stars in the sky on a scale from 1 to 6. He called "
"the very brightest stars in the sky <quote>first magnitude</quote>, and the "
"very faintest stars he could see <quote>sixth magnitude</quote>. Amazingly, "
"two and a half millenia later, Hipparchus's classification scheme is still "
"widely used by astronomers, although it has since been modernized and "
"quantified."
msgstr ""

#: index.docbook:17
#, no-c-format
msgid ""
"The magnitude scale runs backwards to what you might expect: brighter stars "
"have <emphasis>smaller</emphasis> magnitudes than fainter stars)."
msgstr ""

#: index.docbook:22
#, no-c-format
msgid ""
"The modern magnitude scale is a quantitative measurement of the "
"<firstterm>flux</firstterm> of light coming from a star, with a logarithmic "
"scaling:"
msgstr ""

#: index.docbook:26
#, no-c-format
msgid "m = m_0 - 2.5 log (F / F_0)"
msgstr ""

#: index.docbook:28
#, no-c-format
msgid ""
"If you don't understand the math, this just says that the magnitude of a "
"given star (m) is different from that of some standard star (m_0) by 2.5 "
"times the logarithm of their flux ratio. The 2.5 *log factor means that if "
"the flux ratio is 100, the difference in magnitudes is 5 mag. So, a 6th "
"magnitude star is 100 times fainter than a 1st magnitude star. The reason "
"Hipparchus's simple classification translates to a relatively complex "
"function is that the human eye responds logarithmically to light."
msgstr ""

#: index.docbook:37
#, no-c-format
msgid ""
"There are several different magnitude scales in use, each of which serves a "
"different purpose. The most common is the apparent magnitude scale; this is "
"just the measure of how bright stars (and other objects) look to the human "
"eye. The apparent magnitude scale defines the star Vega to have magnitude "
"0.0, and assigns magnitudes to all other objects using the above equation, "
"and a measure of the flux ratio of each object to Vega."
msgstr ""

#: index.docbook:45
#, no-c-format
msgid ""
"It is difficult to understand stars using just the apparent magnitudes. "
"Imagine two stars in the sky with the same apparent magnitude, so they "
"appear to be equally bright. You can't know just by looking if the two have "
"the same <emphasis>intrinsic</emphasis> brightness; it is possible that one "
"star is intrinsically brighter, but further away. If we knew the distances "
"to the stars (see the <link linkend=\"ai-parallax\">parallax</link> "
"article), we could account for their distances and assign "
"<firstterm>Absolute magnitudes</firstterm> which would reflect their true, "
"intrinsic brightness. The absolute magnitude is defined as the apparent "
"magnitude the star would have if observed from a distance of 10 parsecs (1 "
"parsec is 3.26 light-years, or 3.1 x 10^18 cm). The absolute magnitude (M) "
"can be determined from the apparent magnitude (m) and the distance in "
"parsecs (d) using the formula (note that M=m when d=10):"
msgstr ""

#: index.docbook:60
#, no-c-format
msgid "M = m + 5 - 5 * log d"
msgstr ""

#: index.docbook:62
#, no-c-format
msgid ""
"The modern magnitude scale is no longer based on the human eye; it is based "
"on photographic plates and photoelectric photometers. With telescopes, we "
"can see objects much fainter than Hipparchus could see with his unaided "
"eyes, so the magnitude scale has been extended beyond 6th magnitude. In "
"fact, the Hubble Space Telescope can image stars nearly as faint as 30th "
"magnitude, which is one <emphasis>trillion</emphasis> times fainter than "
"Vega!"
msgstr ""

#: index.docbook:70
#, no-c-format
msgid ""
"A final note: the magnitude is usually measured through a color filter of "
"some kind, and these magnitudes are denoted by a subscript describing the "
"filter (&ie;, m_V is the magnitude through a <quote>visual</quote> filter, "
"which is greenish; m_B is the magnitude through a blue filter; m_pg is the "
"photographic plate magnitude, &etc;)."
msgstr ""
