المستندات والموارد - نتائج البحث
نتائج البحث
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)
The Kingdom of Orion
صورة
أُنشئ لصالح OAE
الشرح: Winner in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.
This image, taken in January 2022, pictures a landscape from Navarra, a province in the north of Spain with ruins from old civilizations in the foreground. Above that, we see a partially cloudy and starry sky with the most prominent stars belonging to the star pattern Orion. Composed of many bright stars with several interesting deep sky objects within its boundaries, Orion is one of the 88 officially recognised IAU constellations. It originates from Greek mythology where the hero Orion is the son of the sea god Poseidon. Orion is characterised as a giant hunter lurking just before he attacks an animal (it is unclear which animal he attacks, but, in the original Babylonian version of the Gilgamesh saga, it is the Bull of Heaven depicted as the constellation Taurus). The modern planetarium interpretation depicts him as a Roman warrior raising up his shield, but the two accompanying dogs, represented by the constellations of Canis Major and Canis Minor, are reminiscent of the Greek hunter.
Located at the celestial equator, the star pattern is visible all over the world and is interpreted differently in various mythologies, for example as three fishermen at a campfire in parts of Australia, as a butterfly in some parts of Africa, and as a stairway for the souls of ancestors in parts of South America. As Spain belonged to the Roman empire, the original constellations from earlier times are not known. There are some cave paintings on the Iberian peninsula that could possibly have astronomical references. However, there is uncertainty as to whether these painted figures on rocks depict star patterns.
Orion is best visible from November to January. Its most recognisable feature is the “belt”, an asterism composed of three bright, aligned stars (Alnitak, Alnilam and Mintaka), also recognised by different cultures. Just below this belt is the Orion Nebula, a famous and widely studied star-forming region located about 1500 light-years from Earth. The constellation's brightest stars are Rigel — a blue supergiant which is one of the brightest stars in the sky — and Betelgeuse — a massive red supergiant. The former serves as the left foot, and the latter as the right shoulder of the hunter. While Rigel is in the middle of its life, Betelgeuse is expected to explode within the next few tens of thousands of years. The Orionids, a meteor shower with typical rates of dozens of meteors per hour, whose parent body is Halley’s Comet, can be seen every year in the area of Orion, next to the border with the constellation of Gemini during the month of October.
المصدر: Carlos Zudaire/IAU OAE
مصطلحات المعجم:
مجموعة نجمية او حشد نجمى , العملاق الفائق الأحمر , الجَبّار
فئات:
علم الفلك بالعين المجردة
, 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
هذا الملف على Zenodo ( صورة 2.07 MB)
