بلغات أخرى
- الألمانيّة: Elliptische Galaxie
- الإنجليزيّة: Elliptical Galaxy
- الفرنسيّة: Galaxie elliptique
- الإيطاليّة: Galassia ellittica
- اليابانيّة: 楕円銀河 (رابط خارجي)
- الكوريّة: 타원은하
- الصينيّة المبسطة: 椭圆星系
- الصينيّة التقليدية: 橢圓星系
وسائط ذات صلة
The giant elliptical galaxy ESO 325-G004
الشرح: The giant elliptical galaxy ESO 325-G004 sits in the Abell S0740 galaxy cluster. This huge galaxy has a mass of approximately a hundred billion solar masses. ESO 325-G004 is brightest in its core with its brightness decreasing further from its center. This galaxy has no visible spiral structure or dust lanes. ESO 325-G004 and many of the smaller galaxies around it are members of the galaxy cluster Abell S0740.
المصدر: Cropped from the original by NASA, ESA, and The Hubble Heritage Team (STScI/AURA); J. Blakeslee (Washington State University)
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License: PD الملكية العامة أيقونات
Jet Ejected from the Active Galaxy M87
الشرح: A 3000-light-year-long jet streaming from the core of galaxy M87, as captured by the Hubble Space Telescope. The center of this image shows the core of the elliptical galaxy M87 (in the constellation Virgo) which hosts an active galactic nucleus (AGN).
An AGN is a very luminous region around a supermassive black hole. It is powered by matter falling towards the black hole and forming a hot accretion disk. Many galaxies host a supermassive black hole, but not all of them are accreting enough matter to appear as an AGN.
The strong gravity of the supermassive black hole in the heart of M87 has caused a huge jet of charges particles to be flung out from the accretion disk. This extends far out into the galaxy itself, beyond the core region. Here we see the jet as a whitish-blue line which gets wider the further it goes from the core. The light emission we see here is caused by the energetic electrons in the jet interacting with magnetic fields.
المصدر: NASA, ESA, A. Lessing (Stanford University), E. Baltz (Stanford University), M. Shara (AMNH), J. DePasquale (STScI)
رابط المصدر
License: CC-BY-4.0 المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات
الرسوم التوضيحية المرتبطة
Leo Constellation Map
الشرح: The zodiac constellation Leo and its surrounding constellations. Starting from the top of the diagram and going clockwise, these are Leo Minor, Cancer, Sextans, Hydra, Crater, Virgo and Ursa Major. The brightest star in Leo, Regulus, lies almost exactly on the ecliptic (shown here as a blue line): the path the Sun appears to take across the sky over the course of a year. The Sun spends the period from mid August to mid September in Leo. The other planets in the Solar System can often be found in Leo.
Leo spans the celestial equator and is thus part of it is visible at some time in the year from all of planet Earth with some of the constellation obscured for the most arctic and antarctic regions of the world. Leo is most visible in the evenings in the northern hemisphere spring and southern hemisphere autumn.
Several objects can be seen in Leo, including M65 and M66 – two galaxies in the Leo Triplet, a trio of galaxies including NGC 3628, not listed here. In addition, M96, a spiral galaxy, can be seen as a fuzzy object using a small telescope, and Messier 105, an elliptical galaxy. Each of these objects are labelled on the map as red ellipses.
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 labelled 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 line marking the ecliptic, 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
License: CC-BY-4.0 المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات
Virgo Constellation Map
الشرح: The zodiac constellation Virgo and its surrounding constellations. Starting from the top of the diagram and going clockwise, these are Coma Berenices, Leo, Crater, Corvus, Libra, and Bootes. The brightest star in Virgo, Spica, lies just below the ecliptic (shown here as a blue line) in the middle of the map. One way of locating this star in the night sky is to follow the handle of the Big Dipper to the star Arcturus in Bootes and go along a line straight down to Spica (“arc to Arcturus and spike to Spica”). This star lies just below the ecliptic. The ecliptic is the path the Sun appears to take across the sky over the course of a year. The Sun is in Virgo from mid September to late October. The other planets of the Solar System can often be found in Virgo.
Virgo spans the celestial equator and is thus part of it is visible at some time in the year from all of planet Earth with some of the constellation obscured for the most arctic and antarctic regions of the world. Virgo is most visible in the evenings in the northern hemisphere spring and southern hemisphere autumn.
The constellation Virgo appears as a person lying with their back roughly against the ecliptic, arms outstretched, and feet pointed east. Several deep-sky objects are visible in Virgo, including NGC4697, M49, M87, M86, M84, and M60, all of which are labelled as red ellipses on the map. These are all spiral and elliptical galaxies located several millions of lightyears from Earth. Most notably, M87 is host to the supermassive black hole (Pōwehi) that was imaged by the Event Horizon Telescope in 2019. All of these galaxies are members of the Virgo Cluster, the nearest cluster of galaxies to the Milky Way.
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 labelled 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 line marking the ecliptic, 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
License: CC-BY-4.0 المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات
Coma Berenices Constellation Map
الشرح: The constellation Coma Berenices with its brighter stars and surrounding constellations. Coma Berenices is surrounded by (going clockwise from the top): Canes Venatici, Ursa Major, Leo, Virgo and Boötes. This constellation has relatively few bright stars.
Coma Berenices is a northern constellation close to the celestial equator. As such the whole constellation is visible at some point in the year everywhere on Earth except the most antarctic regions. The constellation is best viewed in the evening in the northern hemisphere late spring and southern hemisphere late autumn.
Coma Berenices is home to a large cluster of galaxies known as the Coma Supercluster. However none of the galaxies in this cluster are marked on this diagram as they are too faint to observe with most amateur telescopes. The elliptical galaxy M85 and the spiral galaxy M100 are members of the nearer Virgo cluster of galaxies. These are marked with red ellipses as are the even nearer M64 and NGC 4565, both of which are spiral galaxies. The globular cluster M53, marked here with a yellow circle with a plus sign superimposed on it, also lies in Coma Berenices.
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. The blue line at the bottom right of the diagram marks the ecliptic. Neither the constellation boundaries, nor the line marking the ecliptic, 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
License: CC-BY-4.0 المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات
