المستندات والموارد - نتائج البحث
نتائج البحث
Planet formation around the star TW Hydrae
صورة
الشرح: This image shows the disk around the young star TW Hydrae. This star is only about 10 million years old, young enough that planets are still forming in a disk of gas and dust around it. This image was created using an array of submillimetre telescopes, each of which looks like a satellite dish. The signals from these telescopes were combined by a central processing computer to make this image. The lighter and darker patches show areas of the disk where there is more or less dust respectively. The dark rings and bright rings are evidence that the dust in the disk has been shepherded into some orbits and away from others. This is likely because there is one or more planets that are still forming hidden in the disk.
The whole image shows the disk around TW Hydrae out to a distance of about 70 astronomical units frm the central star. The two outer dark rings are separated from the central star by approximately the average distance between the Sun and Uranus and the average distance between the Sun and Pluto. The inner central hole appears to have been carved out by a planet orbiting TW Hydrae at a distance similar to the distance between the Earth and the Sun.
المصدر: S. Andrews (Harvard-Smithsonian CfA); B. Saxton (NRAO/AUI/NSF); ALMA (ESO/NAOJ/NRAO)
رابط المصدر
مصطلحات المعجم:
تكوُّن الكواكب
فئات:
الكواكب الخارجية وعلم الأحياء الفلكية
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
210.48 kB)
Witnessing the birth of a star
صورة
الشرح: A combination of radio and visible light imaged with the Atacama Large Millimeter/submillimeter Array (ALMA) and European Southern Observatory's New Technology Telescope (NTT) revealing birth of a star forming the Herbig-Haro object HH 46/47. ALMA observations shown in orange and green unveil the energetic jet from the central protostar otherwise hidden at visible wavelength due to dust obscuration and dense gas. NTT observations in pink and purple highlight the visible light from the jet emitted towards the observer.
المصدر: ESO/ALMA (ESO/NAOJ/NRAO)/H. Arce. Acknowledgements: Bo Reipurth
رابط المصدر
مصطلحات المعجم:
النجوم البدائية , تشكّل النجوم
فئات:
درب التبانة والوسط بين النجمي
, النجوم
الترخيص: المشاع الإبداعي نَسب المُصنَّف 3.0 غير موطَّنة المشاع الإبداعي نَسب المُصنَّف 3.0 غير موطَّنة أيقونات
ملف
( صورة
1.34 MB)
The giant elliptical galaxy ESO 325-G004
صورة
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)
رابط المصدر
مصطلحات المعجم:
المجرة البيضوية , حشد مجري
فئات:
المجرات
الترخيص: الملكية العامة الملكية العامة أيقونات
ملف
( صورة
108.45 kB)
Neowise's metamorphosis, by Tomáš Slovinský and Petr Horálek, Slovakia
صورة
أُنشئ لصالح OAE
الشرح: First place in the 2021 IAU OAE Astrophotography Contest, category Comets.
This image uses the chronophotography technique to capture the evolution of the comet C/2020 F3 (Neowise) over time, as it became visible in the northern skies in July 2020. Orbits of comets are extremely elliptical, which means that during part of their orbit they get close to the Sun. As a comet approaches the Sun, it gets heated, releases gas and dust creating an envelope or coma around the nucleus. The solar wind and photons (particles of electromagnetic radiation) interact with the coma producing the cometary tail, which can be seen clearly in this image. The tail of a comet always points away from the Sun, and extends as much as tens of millions of kilometres. This tail has two parts: the relatively straight bluish gas (ion or plasma) tail, which is made up of charged particles interacting with the magnetic fields of the solar wind; and the whitish dust tail compose of very small dust particles that are pushed by the radiation pressure from the Sun into a curve due to their slower speeds. Two regions in the Solar System are often associated with being “storehouses” of comets: the Kuiper Belt and the Oort Cloud. Comets with periods up to about two hundred years come from the Kuiper belt, a reservoir of cometary nuclei material with a disk-like shape located beyond Neptune. Longer period comets come from the Oort cloud, another huge reservoir of icy objects, with a spherical shape surrounding the Solar System. The outer limit of the Oort Cloud is not known as yet, but it could be as much as 10 thousand times the Sun-Earth distance, or even more. Due to gravitational disturbances, some of these cometary nuclei might be ejected towards the inner regions of the Solar System, sometimes approaching the Earth, offering some of the most spectacular views of a celestial body. The image also shows some prominent constellations and asterisms like the Big and Little Dippers, and also the North (Pole) Star – Polaris.
المصدر: Tomáš Slovinský and Petr Horálek/IAU OAE
مصطلحات المعجم:
المذنب
فئات:
علم الفلك بالعين المجردة
, النظام الشمسي
الترخيص: المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) المشاع الإبداعي نَسب المُصنَّف 4.0 دولي (CC BY 4.0) أيقونات
هذا الملف على Zenodo ( صورة 19.53 MB)
A visible light image of the Andromeda Galaxy
صورة
الشرح: The Andromeda Galaxy viewed in visible light. Like our Milky Way, Andromeda is a barred spiral galaxy. Here we can see its bright core and spiral disk. The glow from the stars in the disk is interrupted by lanes of dust that form part of its spiral structure.
Andromeda is the largest galaxy in the Local Group of galaxies that includes the Milky Way.
To the left of the core and just above the disk we see the dwarf galaxy M32 and to the right and below the disk we see the dwarf galaxy M110. These are both satellite galaxies of the Andromeda Galaxy.
المصدر: Torben Hansen
رابط المصدر
مصطلحات المعجم:
مجرة المرأة المسلسلة , المجرة القرصية , المجرة القزمة , جرم مسييه , المجرة الحلزونية , الشريط المجري
فئات:
المجرات
الترخيص: المشاع الإبداعي نَسب المُصنَّف 2.0 عام المشاع الإبداعي نَسب المُصنَّف 2.0 عام أيقونات
ملف
( صورة
1.10 MB)
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