186 lines
5.7 KiB
Plaintext
186 lines
5.7 KiB
Plaintext
#
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# Alexander Potashev <aspotashev@gmail.com>, 2019.
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msgid ""
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msgstr ""
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"Project-Id-Version: \n"
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"Report-Msgid-Bugs-To: https://bugs.kde.org\n"
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"POT-Creation-Date: 2021-03-28 16:23+0000\n"
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"PO-Revision-Date: 2019-02-24 19:08+0300\n"
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"Last-Translator: Alexander Potashev <aspotashev@gmail.com>\n"
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"Language-Team: Russian <kde-russian@lists.kde.ru>\n"
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"Language: ru\n"
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"MIME-Version: 1.0\n"
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"Content-Type: text/plain; charset=UTF-8\n"
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"Content-Transfer-Encoding: 8bit\n"
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"X-Generator: Lokalize 2.0\n"
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"Plural-Forms: nplurals=4; plural=n==1 ? 3 : n%10==1 && n%100!=11 ? 0 : n"
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"%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2;\n"
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#. Tag: author
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#: cosmicdist.docbook:3
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#, no-c-format
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msgid "<firstname>Akarsh</firstname> <surname>Simha</surname>"
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msgstr "<firstname>Akarsh</firstname> <surname>Simha</surname>"
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#. Tag: title
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#: cosmicdist.docbook:8
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#, no-c-format
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msgid "<title>Cosmic Distance Ladder</title>"
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msgstr ""
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#. Tag: primary
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#: cosmicdist.docbook:9
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#, no-c-format
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msgid "<primary>Cosmic Distance Ladder</primary>"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:10
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#, no-c-format
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msgid ""
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"The cosmic distance ladder refers to the succession of different methods "
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"that astronomers use to measure distances to objects in the sky. Some "
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"methods, like <link linkend=\"ai-parallax\">parallax</link>, work well for "
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"only nearby objects. Other methods, like using the <firstterm>cosmological "
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"redshift</firstterm>, work only for very distance galaxies. Thus, there are "
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"several methods, each with its own limited validity, and hence the name."
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msgstr ""
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#. Tag: title
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#: cosmicdist.docbook:20
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#, no-c-format
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msgid "Direct measurements"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:21
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#, no-c-format
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msgid ""
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"The bottom of the ladder consists of objects whose distances can be directly "
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"measured, like the moon (see <ulink url=\"https://en.wikipedia.org/wiki/"
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"Lunar_Laser_Ranging_experiment\">Lunar Laser Ranging</ulink>). The same "
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"technique, using radio waves, is applied to find distances to planets as "
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"well."
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:29
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#, no-c-format
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msgid ""
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"For nearby stars, measuring the <link linkend=\"ai-parallax\">parallax</"
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"link> is possible and yields the distance to the star."
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msgstr ""
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#. Tag: title
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#: cosmicdist.docbook:37
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#, no-c-format
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msgid "Standard candles"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:38
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#, no-c-format
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msgid ""
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"\"Standard candles\" are objects whose intrinsic brightnesses we can know "
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"for sure. The apparent <link linkend=\"ai-magnitude\">magnitude</link>, "
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"which is easy to measure, tells us how bright an object appears, not how "
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"bright it actually is. Distant objects appear less brighter, because their "
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"light gets spread out over a larger area."
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:45
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#, no-c-format
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msgid ""
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"In accordance with the <firstterm>inverse square law</firstterm> for light "
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"intensities, the amount of light we receive from an object drops with the "
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"distance squared. Thus, we may compute the distance to an object if we know "
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"both how bright it actually is (absolute magnitude; 'M') and how bright it "
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"appears to us on earth (apparent magnitude; 'm'). We may define the "
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"<firstterm>distance modulus</firstterm> as follows:"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:52
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#, no-c-format
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msgid "Distance Modulus = M - m = 5 log<subscript>10</subscript> d - 5"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:54
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#, no-c-format
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msgid ""
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"Here 'd' is the distance measured in <link linkend=\"ai-parallax\">parsecs</"
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"link>."
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:58
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#, no-c-format
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msgid ""
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"For these special standard candle objects, we have some other way of knowing "
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"their intrinsic brightness, and thereby can calculate their distance."
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:63
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#, no-c-format
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msgid "Common \"standard candles\" used in astronomy are:"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:68
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#, no-c-format
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msgid ""
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"Cepheid Variables: A kind of periodic variable star, whose variation period "
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"is related to the luminosity"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:71
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#, no-c-format
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msgid ""
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"RR Lyrae Variables: Another such periodic variable star with a well-known "
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"period-luminosity relationship"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:74
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#, no-c-format
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msgid ""
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"Type-Ia supernovae: These supernovae have a very well-defined luminosity as "
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"a result of the physics that governs them and hence serve as standard-candles"
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msgstr ""
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#. Tag: title
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#: cosmicdist.docbook:83
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#, no-c-format
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msgid "Other methods"
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:84
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#, no-c-format
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msgid ""
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"There are many other methods. Some of them rely on the physics of stars, "
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"such as the relationship between luminosity and color for various types of "
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"stars (this is usually represented on a <firstterm>Hertzsprung-Russel "
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"Diagram</firstterm>). Some of them work for star clusters, such as the "
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"<firstterm>Moving cluster method</firstterm> and the <firstterm>main-"
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"sequence fitting method</firstterm>. The <firstterm>Tully-Fisher relation</"
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"firstterm> that relates the brightness of a spiral galaxy to its rotation "
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"can be used to find the distance modulus, since the rotation of a galaxy is "
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"easy to measure using <firstterm>Doppler shift</firstterm>. Distances to "
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"distant galaxies may be found by measuring the <firstterm>Cosmological "
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"redshift</firstterm>, which is the redshift of light from distance galaxies "
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"that results from the expansion of the universe."
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msgstr ""
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#. Tag: para
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#: cosmicdist.docbook:100
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#, no-c-format
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msgid ""
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"For further information, consult <ulink url=\"https://en.wikipedia.org/wiki/"
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"Cosmic_distance_ladder\">Wikipedia on Cosmic Distance Ladder</ulink>"
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msgstr ""
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