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Ursa Minor appears as a small ladle with the end of the handle, the location of Polaris, at the north pole

Ursa Minor Constellation Map

صورة

الشرح: The constellation Ursa Minor along with its bright stars and its surrounding constellations. Ursa Minor is surrounded by (going clockwise from the top): Cephus, Camelopardalis and Draco. Ursa Minor is notable as its brightest star, Polaris is the northern pole star. Ursa Minor is visible from the entire northern hemisphere with some parts of the constellation being visible from equatorial regions of the southern hemisphere. It is also circumpolar for temperate and arctic regions of the northern hemisphere. Polaris, lying very close the north celestial pole is circumpolar for the whole of the northern hemisphere. The constellation is most visible in the evenings in the northern hemisphere summer and southern hemisphere winter. This diagram maps an area around the north celestial pole. Here lines of constant right ascension converge. The right ascension values (in hours) of these lines are marked on the x-axis above and below the diagram. Some of the lines of constant declination (in degrees) are marked on the y-axis. The sizes of the stars marked here relate to the star's apparent magnitude, a measure of its apparent brightness. The larger dots represent brighter stars. The Greek letters mark the brightest stars in the constellation. These are ranked by brightness with the brightest star being labeled alpha, the second brightest beta, etc., although this ordering is not always followed exactly. The dotted boundary lines mark the IAU's boundaries of the constellations and the solid green lines mark one of the common forms used to represent the figures of the constellations. Neither the constellation boundaries, nor the lines joining the stars appear on the sky.
المصدر: Adapted by the IAU Office of Astronomy for Education from the original by IAU/Sky & Telescope
رابط المصدر

مصطلحات المعجم: القدرالظاهري , الإحداثيات السماوية , النجوم القطبية , مجموعة نجمية او حشد نجمى , الميل , القطب السماوي الشمالي , النجم القطبي , المطلع المستقيم
فئات: علم الفلك بالعين المجردة

الترخيص: المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات

ملف ( صورة 117.26 kB)
ملف PDF (PDF file 165.62 kB)


A line of stars goes from cool faint stars to hot bright stars. Some stars lie above or below this line

Hertzsprung-Russell diagram

صورة
أُنشئ لصالح OAE

الشرح: This diagram shows the temperature and luminosity of different stars. The size of each point represents the star’s radius and its colour is the colour the human eye would see. The stars range in colour from a washed-out blue to a washed-out reddish-orange. No star has a pure colour like red, green or blue as stars’ spectra include light from lots of different colours. However the reddest stars are commonly referred to as red and the bluest stars as blue. The sample of stars used to make this diagram was chosen to show a wide range of stars of different types so the relative number of each type of star is not representative of how commonly each type is found. From the top left to bottom right there is a long line of stars burning hydrogen in their cores. This is called the main sequence. On this line, one sees the stars Mintaka, Achenar, Sirius A, the Sun and Proxima Centauri. The objects around Proxima Centauri at the lower right end of the main sequence are known as red dwarfs. To the lower right of the red dwarfs are Teide 1 and Kelu-1 A. These two objects are brown dwarfs, objects too low in mass to have cores hot enough to fuse hydrogen for a sustained period of time. As they do not burn hydrogen, brown dwarfs are not considered main sequence stars. The name brown dwarf is unrelated to their colour. Above the main sequence, we find subgiants, giants and supergiants. These are stars that have finished burning hydrogen in their core and have evolved into larger objects. A star’s brightness depends on its temperature and size so giant stars are brighter than stars with a smaller radius but the same temperature. In time these objects will move towards the end of their lives and undergo either a planetary nebula phase or become supernovae. Stars which end their lives with a planetary nebula phase become a type of stellar remnant called a white dwarf. Such objects are much smaller than stars of the same temperature and thus are fainter and are found significantly below the main sequence. Stars which end their lives as supernovae become either black holes or neutron stars. These are not shown on this plot.
المصدر: IAU OAE/Niall Deacon

مصطلحات المعجم: القزم البني , اللون , النجم العملاق , مخطط هرتزبرونغ–راسل , اللمعان , التسلسل الرئيسي , تطور النجوم , نجم فائق الضخامة , الأقزام البيضاء , درجة الحرارة الفعالة , نجم شبه عملاق , فئة اللمعان
فئات: النجوم

الترخيص: المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات

ملف ( صورة 66.05 kB)
ملف PDF (PDF file 67.26 kB)


Phoenix appears as a north-south diamond with a right-angled triangle extending from its western corner

Phoenix Constellation Map

صورة

الشرح: The constellation Phoenix with its bright stars and surrounding constellations. Phoenix is surrounded by (going clockwise from the top): Sculptor, Grus, Tucana, Hydrus, Eridanus and Fornax. Phoenix is a southern constellation and thus the whole constellation is visible at some point in the year throughout the northern hemisphere. The whole constellation is also visible to equatorial regions of the southern hemisphere with parts of the constellation visible to most temperate northern regions. Phoenix is circumpolar in antarctic and some temperate regions of the southern hemisphere. The constellation is best viewed in the northern hemisphere late autumn and southern hemisphere late spring. The y-axis of this diagram is in degrees of declination with north as up and the x-axis is in hours of right ascension with east to the left. The sizes of the stars marked here relate to the star's apparent magnitude, a measure of its apparent brightness. The larger dots represent brighter stars. The Greek letters mark the brightest stars in the constellation. These are ranked by brightness with the brightest star being labeled alpha, the second brightest beta, etc., although this ordering is not always followed exactly. The dotted boundary lines mark the IAU's boundaries of the constellations and the solid green lines mark one of the common forms used to represent the figures of the constellations. Neither the constellation boundaries, nor the lines joining the stars appear on the sky.
المصدر: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
رابط المصدر

مصطلحات المعجم: القدرالظاهري , الإحداثيات السماوية , مجموعة نجمية او حشد نجمى , الميل , المطلع المستقيم
فئات: علم الفلك بالعين المجردة

الترخيص: المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات

ملف ( صورة 107.68 kB)
ملف PDF (PDF file 176.94 kB)


Reticulum appears as four stars in a kite shape pointing south west

Reticulum Constellation Map

صورة

الشرح: The constellation Reticulum with its bright stars and surrounding constellations. Reticulum is surrounded by (going clockwise from the top): Horologium, Hydrus and Dorado. Reticulum is a southern constellation and thus the whole constellation are visible at some point in the year throughout the southern hemisphere. The whole constellation is also visible to most equatorial regions of the northern hemisphere, with parts of the constellation visible to the remaining equatorial and some temperate northern regions. Reticulum is circumpolar for all antarctic and most temperate regions of the southern hemisphere. The constellation is best viewed in the evening in the northern hemisphere winter and southern hemisphere summer. The y-axis of this diagram is in degrees of declination with north as up and the x-axis is in hours of right ascension with east to the left. The sizes of the stars marked here relate to the star's apparent magnitude, a measure of its apparent brightness. The larger dots represent brighter stars. The Greek letters mark the brightest stars in the constellation. These are ranked by brightness with the brightest star being labeled alpha, the second brightest beta, etc., although this ordering is not always followed exactly. The dotted boundary lines mark the IAU's boundaries of the constellations and the solid green lines mark one of the common forms used to represent the figures of the constellations. Neither the constellation boundaries, nor the lines joining the stars appear on the sky.
المصدر: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
رابط المصدر

مصطلحات المعجم: القدرالظاهري , الإحداثيات السماوية , النجوم القطبية , مجموعة نجمية او حشد نجمى , الميل , المطلع المستقيم
فئات: علم الفلك بالعين المجردة

الترخيص: المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات

ملف ( صورة 91.30 kB)
ملف PDF (PDF file 149.94 kB)


Leo Minor appears as a flattened diamond with a line extending from its west end

Leo Minor Constellation Map

صورة

الشرح: The constellation Leo Minor with its brighter stars and surrounding constellations. Leo Minor is surrounded by (going clockwise from the top): Ursa Major, Lynx, Cancer and Leo. Leo Minor is a small constellation with relatively few bright stars. It is a separate constellation from and should not be confused with its larger neighbour Leo. Leo Minor is a northern constellation and thus the whole constellation is visible at some point in the year throughout the northern hemisphere. The whole constellation is also visible from equatorial and temperate regions of the southern hemisphere. Leo Minor is circumpolar in arctic regions. This constellation is best viewed in the northern hemisphere spring and southern hemisphere autumn. The y-axis of this diagram is in degrees of declination with north as up and the x-axis is in hours of right ascension with east to the left. The sizes of the stars marked here relate to the star's apparent magnitude, a measure of its apparent brightness. The larger dots represent brighter stars. The Greek letters mark the brightest stars in the constellation. These are ranked by brightness with the brightest star being labeled alpha, the second brightest beta, etc., although this ordering is not always followed exactly. The dotted boundary lines mark the IAU's boundaries of the constellations and the solid green lines mark one of the common forms used to represent the figures of the constellations. Neither the constellation boundaries, nor the lines joining the stars appear on the sky. The blue line in the bottom right marks the ecliptic.
المصدر: Adapted by the IAU Office of Astronomy for Education from the original by the IAU and Sky & Telescope
رابط المصدر

مصطلحات المعجم: القدرالظاهري , الإحداثيات السماوية , النجوم القطبية , مجموعة نجمية او حشد نجمى , الميل , مسار البروج , كوكبة الأسد , المطلع المستقيم
فئات: علم الفلك بالعين المجردة

الترخيص: المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات

ملف ( صورة 88.37 kB)
ملف PDF (PDF file 154.05 kB)


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