Солнечная система для детей: планеты, спутники, звезды, системы

В этой небольшой заметке представлен материал на тему: солнечная система для детей. Простым и понятным языком мы описали о солнечной системе, планетах, которые в ней находятся и многих других интересных вещах.

Во Вселенной существует множество объектов, в числе которых планеты и спутники, звезды и систем, а также галактики. Солнечная система, в которых находится и наша планета Земля также полна как планетами, спутниками, так и астероидами, кометами, и многих других интересных объектов. На сегодняшний день ученые предполагают, что наша Солнечная система была образована из гигантского облака газа и пыли. В ней 8 планет, которые делятся на 2-е группы – внутренние планеты (они же планеты земной группы) . В эту группу входит Меркурий, Венера, Земля (третья планета от Солнца) и Марс. И внешние планеты или газовые гиганты: Юпитер, Сатурн, Уран и Нептун.

Между этими двумя группами находится пояс астероидов. А за газовыми гигантами располагаются транснептуновые объекты. Самый крупный из которых Плутон. Раньше Плутон считался обычной планетой, но сейчас он причисляется к карликовым планетам и в то же время самым крупным объектом в поясе Койпера.

Пояс Койпера – похож на пояс астероидов, но отличается тем, что он в 20 раз шире его, а также своим составам.

Солнечная система

Как запомнить планеты и их порядок?

Короткие мнемонические фразы они же мнемоники облегчают запоминание разной информации путем образования искусственных ассоциаций.

На этой страничке мы собрали запоминалки планет Солнечной системы для детей, которые облегчат эту, порой, не простую задачу. Единственный нюанс, что когда они придумывались Плутон – относили к планетам, и, поэтому он присутствует почти во всех запоминалках. А как мы знаем — с 2006 года Плутон стал считаться карликовой планетой, и сейчас при заучивании – его можно опускать.

Запоминалки планет Солнечной системы

Запомнить порядок планет Солнечной системы (Меркурий, Венера, Земля, Марс, Юпитер, Сатурн, Уран, Нептун, Плутон) можно по первым буквам слов М-Меркурий В-Венера З-Земля М-Марс Ю-Юпитер С-Сатурн У-Уран Н-Нептун П-Плутон во фразах:

• Мы Ведь Знаем — Мама Юли Села Утром На Пилюли!
• Медвежонок Ветчину Закусил Малиной, Юркий Суслик Утащил Ножик Перочинный.
• Морозным Вечером Залез на Мачту Юнга Стремясь Увидеть Незнакомый Порт.
• Мама Всегда Запрещала Мне Юному Следопыту Узнать Названия Планет.
• Морской Волк Замучил Молодуго Юнгу, Совершенно Утомив Несчастного Парня.
• Мы Встретимся Завтра, Мой Юный Спутник, У Новой Планеты.
• Мудрая Волшебница Златоглавая Модница Южных Стран Увлекается Новейшей Поэзией.
• Мы Все Знаем: Многие Юные Сурки Учат Названия Планет.
• Можно Вылететь За Марс, Ювелирно Свернув У Нашей Планеты.
• Мама Варит Земляничный Морс, а Юный Сын Уже Не Плачет.
• Мерял Веня Землю Марусиной Юбкой, Сатиновой да Урановой, Непутёвый он Плут.
• Мрачное Венерическое Заболевание Может Юрко Сразить Усталую Нимфоманку.
• Меньше Всего Замечает Мария Южного Солнца Улыбку На Пляже.
• Медленно Везёт Землю Маленький Питер; Сад Украшен Небьющимися Плафонами (мнемоника планет Алексея Головнина).
• Мечтая Выйти Замуж, Мало Юбку Снять — Улыбнуться Надо и Поцеловать.

Запоминание порядка планет с поясом астероидов

Маша Веником Землю Мела, А Юра Сидел У Норы Паука.
То есть в этой фразе добавилось буква «А» — пояс Астероидов.

Запоминалка планет от самой дальней планеты (Плутона) до самой ближней (Меркурия) до Солнца

Планеты Нетрудно Упомнить Самому Юному Малышу, Зная Венеру, Меркурий.

Стихи для запоминания планет

Между волками зайчишка метался,
юркнул, споткнулся, упал —
не поднялся.

По порядку все планеты
Назовет любой из нас.
Раз Меркурий, два Венера,
три Земля, четыре Марс.
Пять Юпитер, шесть Сатурн,
Семь Уран, за ним Нептун.
Он восьмым идет по счету,
и совсем уже потом
и девятая планета под названием Плутон

На Луне жил звездочёт
Он планетам вёл учёт:
МЕРКУРИЙ — раз,
ВЕНЕРА — два-с,
Три — ЗЕМЛЯ,
Четыре — МАРС,
Пять — ЮПИТЕР,
Шесть — САТУРН,
Семь — УРАН,
Восемь — НЕПТУН,
Девять — дальше всех ПЛУТОН,
Кто не видит — выйди вон!

Стих для запоминания 8 планет без Плутона

Меркурий — раз, Венера — два-с,
Три — Земля, четыре — Марс,
Пять — Юпитер, шесть — Сатурн,
Семь — Уран, восьмой — Нептун

Белый стих для запоминания порядка планет

Мерить век земной мало
юность сада убога
нет плодов

Другие способы запоминания порядка планет солнечной системы для детей и взрослых

Еще один способ запоминания порядка планет – это сравнение с другими, но похожими словами и составление предложения с их использованием.
К примеру: Меркнет (Меркурий) моя подруга Венера (Венера) на Земле (Земля). Потому что съела Марс (Марс), лежавший на пюпитре (Юпитер), а обёртку бросила в полную, то есть сытую урну (Сатурн), крикнув после этого «Ура» (Уран). И не ПТУ (Нептун), а институт окончила, сбежав потом с каким-то плутом (Плутон).

Между двумя богами на букву М: Меркурием и Марсом стоят 2 женщины: Венера и Земля. За богом Марсом стоит его папа — Юпитер. За верховным богом Юпитером — уникальная своими кольцами планета — Сатурн. В названии Сатурн зашифрован как Сатурн (САТ), так и последующие планеты: Уран (УР) и Нептун (Н). Следующий за ними Плутон планетой не является, но выглядит как пёсик Плуто с недоумением смотрящий на пантеон греческих богов перед ним.

Акронимы для запоминания планет

Еще один способ выучить порядок планет – использования акронима – то есть аббревиатуры, которая образуется первыми звуками слов во фразе. То есть это слово, которое можно произнести слитно, при этом оно является сокращением. Для заучивания планет можно запомнить акроним: МеВеЗеМа ЮСУНП.

Вы тоже знаете какие-нибудь интересные запоминалки или оригинальные способы заучивания планет Солнечной системы? Пишите их в комментариях.

90000 Planets | Cool Kid Facts 90001 90002 Please support Cool Kid Facts by emailing or sharing! 90003 90004 90005 Email 90006 90005 Pin 90006 90005 Facebook 90006 90011 90002 Let’s learn all about the planets of our solar system! 90003 90002 90003 90002 There are eight planets in our solar system, but did you know there used to be nine of them? 90003 90002 Let’s dive right in and explore the planets. 90003 90002 Our list below also includes the Sun and the Moon! 90003 90002 90003 90002 Earth Facts 90003 90002 90003 90002 Moon Facts 90003 90002 90003 90002 Sun Facts 90003 90002 90003 90002 Jupiter Facts 90003 90002 90003 90002 Mars Facts 90003 90002 90003 90002 Mercury Facts 90003 90002 90003 90002 Neptune Facts 90003 90002 90003 90002 Saturn Facts 90003 90002 90003 90002 Uranus Facts 90003 90002 90003 90002 Venus Facts 90003 90002 How is your planet knowledge? Feel free to let us know.90003 90002 And next, why not explore our world of Earth Science? 90003 90002 90003 90002 Please support Cool Kid Facts by emailing or sharing! 90003 90004 90005 Email 90006 90005 Pin 90006 90005 Facebook 90006 90011.90000 Planet Facts for Kids 90001 90002 A 90003 planet 90004 is a large object such as Jupiter or Earth that orbits a star. It is smaller than a star, and it does not make light. 90005 90002 Planets are shaped like a slightly squashed ball (a spheroid). Objects that orbit planets are called satellites. A star and everything which orbits it are called a star system. 90005 90002 There are eight planets in our Solar System. Pluto used to be called a planet, but in August 2006, the International Astronomical Union decided it was a dwarf planet instead.There are four more known dwarf planets in the Solar System, Ceres, Makemake, Eris and Haumea. 90005 90002 The name «planet» is from the Greek word πλανήτης (90011 planetes 90012), meaning «wanderers», or «things that move». Until the 1990s, people only knew of those in the Solar System. As of June 2011, we know of 563 other planets. All of these newly found planets are orbiting other stars: they are 90011 extrasolar 90012 planets. Sometimes people call them «exoplanets». 90005 90016 In the Solar System 90017 Main page: History of astronomy 90018 90002 The planets in the Solar System have names of Greek or Roman gods, apart from Earth, because people did not think Earth was a planet in old times.However, Earth is occasionally referred by the name of a Roman god: 90011 Terra 90012. Other languages, for example Chinese, use different names. Moons also have names of gods and people from classical mythology, or from the plays written by Shakespeare. 90005 90023 Planets 90024 90002 Here is a list of planets in the Solar System. They are ordered by how close they are to the Sun, nearest first. 90005 90023 Types of planets 90024 90029 90002 Astronomers speak about 90011 major 90012 (or true) planets, and minor planets, which are smaller objects that go around the Sun.Some examples of «minor planets» are asteroids, comets, and trans-Neptunian objects. 90005 90002 Planets in the Solar System are of three sorts: 90005 90036 90037 90011 Terrestrial 90012 or 90011 rocky 90012: Planets that are similar to Earth — in them is mostly rock: Mercury, Venus, Earth, Mars. 90042 90037 90011 Jovian 90012 or 90011 gas giant 90012: These planets are mostly made of gas: Jupiter, Saturn, Uranus, Neptune. Uranian planets are a special sort of gas giants, they have more hydrogen and helium.90042 90037 90011 Icy 90012: Sometimes people also have a third sort, for bodies such as Pluto (though Pluto is no longer called a planet by everyone). These planets are mostly made of ice. 90042 90053 90002 Many objects in the Solar System that are not planets are also «icy». Examples are the icy moons of the outer planets of the Solar System (like Triton). 90005 90016 Related pages 90017 90016 Images for kids 90017 90036 90037 90062 90002 Printed rendition of a geocentric cosmological model from 90011 Cosmographia 90012, Antwerp, тисячі п’ятсот тридцять дев’ять 90005 90042 90037 90069 90002 The Greek gods of Olympus, after whom the Solar System’s Roman names of the planets are derived 90005 90042 90037 90074 90002 An artist’s impression of protoplanetary disk 90005 90042 90037 90079 90002 Asteroid collision — building planets (artist concept).90005 90042 90037 90084 90002 Exoplanets, by year of discovery, through September 2014. 90005 90042 90037 90002 Artist’s impression of a super-Jupiter around the brown dwarf 2M1207. 90005 90042 90037 90093 90002 Earth’s axial tilt is about 23.4 °. It oscillates between 22.1 ° and 24.5 ° on a 41,000-year cycle and is currently decreasing. 90005 90042 90037 90098 90002 Illustration of the interior of Jupiter, with a rocky core overlaid by a deep layer of metallic hydrogen 90005 90042 90037 90103 90042 90037 90106 90042 90053.90000 90001 Astronomy for Kids — Free Games, Fun Facts, Cool Projects, Science Online 90002 90003 90004 90005 90003 90007 90008 Explore the universe with astronomy for kids and enjoy our free games, fun facts, cool quizzes, amazing videos, science fair projects and more! 90009 90007 Learn about planets, stars, moons, galaxies, asteroids, comets, telescopes and all kinds of astronomical objects. As well as activities for children, there are also lesson plans and worksheets for teachers, science ideas for parents and a whole host of online teaching resources for anyone interested in stars, planets, and the subject of astronomy.90009 90012 90013 90012 90003 90016 90017 Sponsored Links 90018 90009 90012 90021 90022 90023 90004 90005 90003 90016 Sponsored Links 90009 90012 90013 90031 90012 90021 90022 90004 90005 90003 90007 Challenge your knowledge of space and astronomy by trying one of our fun astronomy quizzes. How much do you know about galaxies, planets, the Sun, the Moon and the Solar System? 90009 90040 90005 90013 90043 90012 90013 90016 Space and Astronomy Quiz 90009 90016 Can you name the planet famous for its big red spot? Enjoy the challenging questions and fun trivia of our space and astronomy quiz.90009 90012 90021 90005 90013 90054 90012 90013 90016 Space Word Scramble 90009 90016 Interested in astronomy? 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Find out the answer to these and more Earth, Sun and Moon questions with this fun astronomy game.90009 90012 90021 90022 90064 90012 90021 90005 90003 90007 Check out these fun astronomy facts for kids and learn more about asteroids, meteoroids, moons, the Solar System and the closest stars to Earth. 90009 90090 90005 90013 90093 90012 90013 90016 Asteroid Facts 90009 90016 Learn about the Solar System’s asteroid belt, potential asteroid collisions with Earth and more. 90009 90012 90021 90005 90013 90104 90012 90013 90016 Meteoroid Facts 90009 90016 Find out how fast meteoroids travel, how often they make it through Earth’s atmosphere and more with our range of meteoroid facts.90009 90012 90021 90005 90013 90115 90012 90013 90016 Closest Stars to Earth 90009 90016 What are the closest stars to Earth? Find out with our top ten list that features binary stars such as Sirius and Alpha Centauri. 90009 90012 90021 90005 90013 90126 90012 90013 90016 Solar System Facts 90009 90016 Learn about the Sun, terrestrial planets, gas giants, moons, asteroid belt and Earth with our list of interesting solar system facts for kids. 90009 90012 90021 90005 90013 90137 90012 90013 90016 Solar System Moons 90009 90016 Learn about a range of the Solar System’s unique moons such as Titan, Charon, Io, Europa, Ganymede, Callisto, Triton, Phobos and Deimos.90009 90012 90021 90022 90064 90012 90003 90012 90003 90007 Take a look at these great astronomy videos. See how the Solar System was born, watch an amazing black hole animation, learn about the Hubble Space Telescope and more. 90009 90154 90005 90013 90012 90013 90012 90021 90005 90013 90012 90013 90016 Black Hole 90009 90016 Check out this cool animation of a black hole destroying a star. 90009 90012 90021 90005 90013 90012 90013 90012 90021 90005 90013 90012 90013 90016 Kepler Mission 90009 90016 This short documentary focuses on NASA’s planet finding Kepler mission.90009 90012 90021 90022 90064 90012 90021 90005 90003 90007 Get some great ideas for a range of fun astronomy science fair projects. Take a look at out suggested topics, find one that interests you and give it a try! 90009 90195 90005 90013 90198 90012 90013 90016 Astronomy Science Fair Project Ideas 90009 90016 Check out all our space and astronomy related science fair project ideas for kids. Choose from a number of questions and topics including: 90009 90205 90206 Why do planets orbit the sun in an elliptical shape? 90207 90206 Make a model mars rover that can navigate rocky terrain.90207 90206 Discuss the possibility of life on another planet. 90207 90206 Study the phases of the moon. 90207 90214 90012 90021 90022 90064 90012 90003 90012 90003 90007 Check out our cool range of free astronomy pictures, photos and diagrams. 90009 90007 Find interesting images of supernovas, nebulas, galaxies, stars, planets, moon phases, Hubble images and more. 90009 90012 90021 90005 90003 90007 Enjoy a range of astronomy lesson plans, teaching resources, classroom ideas and fun worksheets.Find activities and information on topics such living on the Moon, making a spaceship and more. 90009 90040 90005 90013 90236 90012 90013 90016 Make a Comet 90009 90016 Make a comet and follow its path through the Solar System with this fun astronomy lesson plan for kids. 90009 90012 90021 90005 90013 90247 90012 90013 90016 Living on the Moon 90009 90016 Have you ever thought what life would be like if you were living on the Moon or another planet? Design and build a futuristic city with this in mind.90009 90012 90021 90005 90013 90258 90012 90013 90016 Make a Spaceship 90009 90016 Create a spaceship, space station or satellite using recycled objects such as cardboard, newspaper and bottles. 90009 90012 90021 90005 90013 90269 90012 90013 90016 Space Word Search 90009 90016 How quickly can you find words related to space and astronomy? Find out with this printable space word search for kids. 90009 90012 90021 90022 90064 90012 90003 90012 90003 90007 Enjoy our cool planet facts.Learn about terrestrial planets such as Venus and Mars, gas giants like Jupiter and Saturn as well as dwarf planets like Pluto. Find out how far from the Sun they are, what their atmosphere is like and what makes them unique. 90009 90154 90005 90013 90289 90012 90013 90016 Saturn Facts 90009 90016 Learn more about the planet Saturn and its amazing rings. 90009 90012 90021 90005 90013 90300 90012 90013 90016 Uranus Facts 90009 90016 Did you know that Uranus rolls like a barrel rather than spinning like Earth? 90009 90012 90021 90005 90013 90311 90012 90013 90016 Neptune Facts 90009 90016 Learn about the extreme weather conditions on Neptune with our fun facts for kids.90009 90012 90021 90005 90013 90322 90012 90013 90016 Dwarf Planet Facts 90009 90016 Enjoy a range of interesting facts about Pluto, Eris and other dwarf planets. 90009 90012 90021 90022 90064 90012 90021 90005 90003 90007 Check out our fun facts and information about famous astronomers and scientists who have contributed important theories, ideas and research to the field of astronomy. 90009 90339 90005 90013 90342 90012 90013 90016 Galileo Galilei 90009 90016 Galileo built telescopes and used them to observe the night sky.He discovered Jupiter’s four largest moons and changed the way people thought about the Solar System. 90009 90012 90021 90005 90013 90353 90012 90013 90016 Isaac Newton 90009 90016 Among other things, Isaac Newton was a brilliant astronomer whose law of gravitation marked an important stepping stone in our understanding of the Universe. 90009 90012 90021 90005 90013 90364 90012 90013 90016 Edwin Hubble 90009 90016 Enjoy our interesting facts about Edwin Hubble, an American astronomer famous his work on astrophysics and his subsequent namesake, the Hubble Space Telescope.90009 90012 90021 90022 90012 90003 90012 90003 90012 90021 90022 90012 90022.90000 planet | Definition, Characteristics, & Facts 90001 90002 90003 Planet 90004, (from Greek 90005 planētes 90006, «wanderers»), broadly, any relatively large natural body that revolves in an orbit around the Sun or around some other star and that is not radiating energy from internal nuclear fusion reactions. In addition to the above description, some scientists impose additional constraints regarding characteristics such as size (eg, the object should be more than about 1,000 km [600 miles] across, or a little larger than the largest known asteroid, Ceres), shape ( it should be large enough to have been squeezed by its own gravity into a sphere-i.e., roughly 700 km [435 miles] across, depending on its density), or mass (it must have a mass insufficient for its core to have experienced even temporary nuclear fusion). As the term is applied to bodies in Earth’s solar system, the International Astronomical Union (IAU), which is charged by the scientific community with classifying astronomical objects, lists eight planets orbiting the Sun; in order of increasing distance, they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.Pluto also was listed as a planet until 2006. Until the close of the 20th century, the only planets to be recognized were components of Earth’s solar system. At that time astronomers confirmed that other stars have objects that appear to be planets in orbit around them. 90007 The eight planets of the solar system and Pluto, in a montage of images scaled to show the approximate sizes of the bodies relative to one another. Outward from the Sun, which is represented to scale by the yellow segment at the extreme left, are the four rocky terrestrial planets (Mercury, Venus, Earth, and Mars), the four hydrogen-rich giant planets (Jupiter, Saturn, Uranus, and Neptune), and icy, comparatively tiny Pluto.90008 NASA / Lunar and Planetary Laboratory 90009 90002 Britannica Quiz 90007 90002 Giants of Our Solar System 90007 90002 Uranus was discovered by English astronomer William Herschel. What name did he suggest for his new discovery? 90007 90016 Planets of the solar system 90017 90002 The idea of ​​what exactly constitutes a planet of the solar system has been traditionally the product of historical and cultural consensus.Ancient sky gazers applied the term 90005 planet 90006 to the seven celestial bodies that were observed to move appreciably against the background of the apparently fixed stars. These included the Sun and Earth’s Moon, as well as the five planets in the modern sense-Mercury, Venus, Mars, Jupiter, and Saturn-that were readily visible as celestial wanderers before the invention of the telescope. After the idea of ​​an Earth-centred cosmos was dispelled (90005 see 90006 Copernican system) and more distinctions were made about the nature and movement of objects in the sky, the term 90005 planet 90006 was reserved only for those larger bodies that orbited the Sun .When the giant bodies Uranus and Neptune were discovered in 1781 and 1846 respectively, their obvious kinship with the other known planets left little question regarding their addition to the planetary ranks. So also, at first, appeared to be the case for Pluto when, during a concerted search for a ninth planet, it was observed in 1930 as a seemingly lone object beyond the orbit of Neptune. In later decades, however, Pluto’s planetary status became increasingly questioned by astronomers who noted that its tiny size, unusual orbital characteristics, and composition of ice and rock made it an anomaly among the other recognized planets.After many more Pluto-sized and smaller icy objects were found orbiting beyond Neptune beginning in the 1990s, astronomers recognized that Pluto, far from being unique in its part of the solar system, is almost undoubtedly one of the larger and nearer pieces of this debris , known collectively as the Kuiper belt, that is left over from the formation of the planets. (90005 See also 90006 planetesimal.) 90007 90002 In August 2006, after intense debate over the question of Pluto’s planetary status, the general assembly of the IAU approved a definition for a solar system planet that excluded Pluto.At the same time, it defined a new distinct class of objects called dwarf planets, for which Pluto qualified. Following the IAU proclamations, many scientists protested the definitions, considering them flawed and unscientific and calling for their reconsideration. 90007 90002 According to the 2006 IAU decision, for a celestial body to be a planet of the solar system, it must meet three conditions: it must be in orbit around the Sun, have been molded by its own gravity into a round or nearly round shape , and have «cleared the neighbourhood around its orbit,» meaning that its mass must be large enough for its gravity to have removed rocky and icy debris from its orbital vicinity.Pluto failed on the third requirement because it orbits partially within, and is considered to be part of, the Kuiper belt. 90007 Get exclusive access to content from our тисяча сімсот шістьдесят вісім First Edition with your subscription. Subscribe today 90002 To be a dwarf planet under the IAU definition, the object must meet the first two conditions described above; in addition, it must not have cleared its neighbourhood, and it must not be a moon of another body. Pluto falls into this category, as do the asteroid Ceres and the large Kuiper belt object Eris, which was discovered in 2005 beyond the orbit of Pluto.By contrast, Charon, by virtue of its being a moon of Pluto, is not a dwarf planet, even though its diameter is more than half that of Pluto. The ranks of dwarf planets will likely be expanded as other objects known or yet to be discovered are determined to meet the conditions of the definition. 90007 90002 In June 2008 the IAU created a new category, plutoids, within the dwarf planet category. Plutoids are dwarf planets that are farther from the Sun than Neptune; that is, they are the largest objects in the Kuiper belt.Two of the dwarf planets, Pluto and Eris, are plutoids; Ceres, because of its location in the asteroid belt, is not. 90007 90002 Of the eight currently recognized planets of the solar system, the inner four, from Mercury to Mars, are called terrestrial planets; those from Jupiter to Neptune are called giant planets or Jovian planets. Between these two main groups is a belt of numerous small bodies called asteroids. After Ceres and other larger asteroids were discovered in the early 19th century, the bodies in this class were also referred to as minor planets or planetoids, but the term 90005 asteroid 90006 is now used most widely.90007 90016 Planets of other stars 90017 90002 The planets and other objects that circle the Sun are thought to have formed when part of an interstellar cloud of gas and dust collapsed under its own gravitational attraction and formed a disk-shaped nebula. Further compression of the disk’s central region formed the Sun, while the gas and dust left behind in the midplane of the surrounding disk eventually coalesced to form ever-larger objects and, ultimately, the planets. (90005 See 90006 solar system: Origin of the solar system.) Astronomers have long wondered if this process of planetary formation could have accompanied the birth of stars other than the Sun. In the glare of their parent stars, however, such small, dim objects would not be easy to detect directly in images made with telescopes from Earth’s vicinity. Instead, astronomers concentrated on attempting to observe them indirectly through the gravitational effects they exert on their parent stars. After decades of searching for such extrasolar planets, astronomers in the early 1990s indirectly identified three planets circling a pulsar (i.e., a rapidly spinning neutron star) called PSR B1257 + 12. The first discovery of a planet revolving around a star more like the Sun came in 1995 with the announcement of the existence of a massive planet orbiting the star 51 Pegasi. In the first 15 years after these initial discoveries, about 200 planets around other stars were known, and in 2005 astronomers obtained the first direct infrared images of what were interpreted to be extrasolar planets. In size these objects range from a fraction of the mass of Jupiter to more than a dozen times its mass.Astronomers have yet to develop a rigorous, generally accepted definition of planet that will successfully accommodate extrasolar planets and distinguish them from bodies that are more starlike in character (e.g., brown dwarfs). 90007 The Editors of Encyclopaedia Britannica .