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Formy planetarnyh tumannostei
S. B. Popov/GAISh, Moskva, 29 iyunya 2020

Planetarnye tumannosti zachastuyu imeyut prichudlivye formy. V stat'e kratko obsuzhdayutsya osnovnye mehanizmy ih vozniknoveniya.

• >> Formy planetarnyh tumannostei   (S. B. Popov/GAISh, Moskva, 29.06.2020 21:30, 7.5 KBait, otvetov: 5) Planetarnye tumannosti voznikayut na final'nyh stadiyah evolyucii zvezd s massoi menee primerno 10 solnechnyh. Zvezda asimptoticheskoi vetvi gigantov sbrasyvaet obolochku. V centre ostaetsya goryachee yadro, kotoroe svoim ul'trafioletovym izlucheniem podderzhivaet veshestvo tumannosti v ionizovannom sostoyanii. Vposledstvii yadro planetarnoi tumannosti stanet belym karlikom.

  V nashei Galaktike imeetsya do 10 000 planetarnyh tumannostei. Tipichnoe vremya zhizni (ot sbrosa obolochki do sostoyaniya, kogda veshestvo rekombiniruet stanovitsya neitral'nym) poryadka 10 000 let. T.o., v Galaktike obrazuetsya primerno odna planetarnaya tumannost' v god.

  Planetarnye tumannosti imeyut tipichnyi razmer (diametr) nemnogim menee odnogo parseka. Sootvetstvenno, tumannost' imeet uglovoi razmer, ravnyi lunnomu disku, s rasstoyaniya okolo 100 parsek. Massa veshestva tumannosti sostavlyaet primerno neskol'ko desyatyh massy Solnca.

  V pervom priblizhenii mozhno ozhidat', chto planetarnaya tumannost' budet imet' sfericheskuyu (kak u tumannosti Kol'co v sozvezdii Liry, M57 v kataloge Mess'e) ili slegka vytyanutuyu formu. Odnako sushestvuyut processy, kotorye mogut zametno raznoobrazit' formu tumannosti.

  Osnovnye krupnomasshtabnye struktury planetarnyh tumannostei imeyu central'nuyu, osevuyu ili zerkal'nuyu simmetriyu. K osnovnym elementam mozhno otnesti struinye vybrosy (napravlenie kotoryh mozhet menyat'sya, chto v chastnosti, privodit k poyavleniyu spiralevidnyh struktur), diski i kol'ceobraznye struktury v ploskosti orbity dvoinoi sistemy, a takzhe kol'cevye figury bol'shogo masshtaba (sm. ris 1 v etoi stat'e). Raznye figury mogut nakladyvat'sya drug na druga. Ih peresechenie takzhe mozhet soprovozhdat'sya poyavleniem neobychnyh form

  
  Saturn Nebula.

  Vozniknovenie kol'ceobraznyh struktur s razmerom poryadka razmera vsei tumannosti svyazano s izmeneniem tempa istecheniya veshestva ot central'noi zvezdy. Takaya peremennost' mozhet vliyat' i na vid drugih obrazovanii v tumannosti.

  Vazhnym faktorom formirovaniya slozhnoi struktury tumannosti mozhet yavlyat'sya dvoistvennost' zvezdy. Dvizhenie zvezdy, sbrasyvayushei obolochku, vokrug centra mass sistemy mozhet privodit' k vozniknoveniyu bipolyarnyh i spiralevidnyh struktur slozhnoi formy.

  Vzaimodeistvie zvezd v sisteme s obshei obolochkoi mozhet privodit' k formirovaniyu diskoobraznoi (kol'ceobraznoi) struktury vokrug vsei sistemy. Eta struktura, imeyushaya bOl'shuyu plotnost', chem okruzhayushee veshestvo, ne tol'ko mozhet byt' vidna sama po sebe, no takzhe budet vliyat' na formu tumannosti v dal'neishem, poskol'ku veter, istekayushii ot zvezdy, budet s bol'shei legkost'yu prodvigat'sya v napravlenii, perpendikulyarnom disku, a vblizi ploskosti diska dvizhenie budet zatrudneno. Tak mogut formirovat'sya bipolyarnye (v tom chisle konusovidnye) struktury.

  
  Necklace nebula.

  Esli vtorym komponentom dvoinoi yavlyaetsya belyi karlik, to peretekanie veshestva na nego mozhet privodit' k formirovaniyu akkrecionnogo diska. Takaya sistema mozhet privodit' k poyavleniyu struinyh vybrosov (dzhetov), b'yushih v protivopolozhnyh napravleniyah perpendikulyarno ploskosti diska.

  Iz-za precessii napravlenie vybrosov mozhet menyat'sya (sm. video zdes'). Krome togo, mozhet menyat'sya temp peretekaniya veshestva na belyi karlik, chto budet privodit' k vklyucheniyu/vyklyucheniyu moshnyh vybrosov.

  Diski sami mogut yavlyat'sya istochnikom vetra, chto formiruet tumannosti neobychnogo vida (sm. komp'yuternoe modelirovanie na saite). Poskol'ku disk dvumernoe obrazovanie (vozmozhno, slegka izognutoe), to i istechenie ot diska imeet sootvetstvuyushuyu simmetriyu, v otlichie ot istechenii ot central'noi zvezdy.

  Dvizhenie zvezdy, formiruyushei tumannost', otnositel'no mezhzvezdnoi sredy mozhet dopolnitel'no vliyat' na formu za schet vzaimodeistviya so vstrechnym potokom veshestva.

  Planetarnye tumannosti mogut voznikat' v zvezdnyh skopleniyah, v tom chisle dostatochno plotnyh. Izvestny planetarnye tumannosti v sharovyh skopleniyah, gde zvezdy mogut byt' raspolozheny ochen' blizko drug ot druga.

  Formirovanie struktur planetarnyh tumannostei v troinyh sistemah bylo rassmotreno v rabote Soker (2004). V chastnosti, vazhnym faktorom yavlyaetsya akkreciya veshestva i obrazovanie vybrosov tesnoi dvoinoi sistemoi, vrashayusheisya vokrug teryayushego veshestvo giganta. Eto mozhet privodit' k detalyam v tumannosti, ne demonstriruyushim yarko vyrazhennoi simmetrii (NGC 6210, NGC 1514).

  Nablyudaemye v vidimom diapazone cveta tumannostei obychno obuslovleny emissionnymi liniyami opredelennyh himicheskih elementov (vodorod, kislorod, sera, azot, gelii), a takzhe rasseivaniem sveta pyl'yu. Eti veshestva v obilii vstrechayutsya v estestvennyh usloviyah. Tak za ottenki krasnogo obychno otvetstvenen vodorod, za zelenyi kislorod.

  Nekotoraya informaciya o cvetah tumannostei dostupna na saite clarkvision.com.

  Otmetim, chto vid tumannosti razlichen v raznyh oblastyah spektra. V chastnosti, infrakrasnye nablyudeniya pokazyvayut nalichie slozhnym po forme struktur, svyazannyh s nalichiem pyli. Podcherknem, chto yarkii vid nekotoryh tumannostei na snimkah svyazan s dopolnitel'nym usilenie kontrasta pri obrabotke. T.e., glazom byla by vidna bolee bleklaya kartina. Krome togo, chasto mozhno uvidet' kompozitnye izobrazheniya, sobrannye iz snimkov v raznyh uchastkah spektra, na kotoryh nevidimoe glazom izluchenie oboznacheno uslovnymi cvetami.

  Katalogi diffuznyh tumannostei (kuda takzhe popadaet neskol'ko tumannostei drugih tipov, naprimer, ostatkov sverhnovyh) mozhno naiti po etim ssylkam:
  http://galaxymap.org/cat/list/rcw/1,
  http://galaxymap.org/cat/list/gum/1,
  http://galaxymap.org/cat/list/sharpless/1.

• Re: Formy planetarnyh tumannostei   (Oleg Romanov, 8.09.2020 12:45, 179 Bait, otvetov: 4) Zanimatel'nya astronomiya. Vsegda interesno chitat' vashi stat'i i vyvody.
  zhal' chto seichai astrofizike posvyashayut vse men'she vremeni. Eto ved' ochen' interesnaya nauka dlya vseh
• Re[2]: Formy planetarnyh tumannostei   (Oleg Frolov, 8.09.2020 12:51, 68 Bait, otvetov: 3) Astranomiya seichas horosho razvivaetsya. Ne tak kak hotelos' by konechno
• Re[3]: Formy planetarnyh tumannostei   (Oleg Romanov, 8.09.2020 12:55, 517 Bait) Okolo Moskvy seichas stroyat novyi astronomicheskii centr. Ya tam rabotayu. Rukovoditelem na betonnyh rabotah. Vy zhe navernoe znaete chto kupit' beton v Moskve seichas ne sostavlyaet nikakoi problemy. Cena dovol'no dostupnaya a esli pokupat' beton optom to budet eshe vygodnei. Tak vot, v sleduyushem godu centr nachnet rabotat' uzhe. Tak chto ne stoit rasstraivat'sya, budem izuchat' zvezdy.
  Ya sam astronom lyubitel'. No osnovnaya moya rabota eto konechno zhe stroitel'stvo i zalivka betona
• Silver Bengal Cat   (ths store, 27.01.2023 15:45, 2.3 KBait, otvetov: 1) The Silver Bengal is a breed of domestic cat with a beautiful silvery coat, striking green eyes and distinctive Bengal spots. Known for their playful and energetic personalities, these cats make great companions for anyone looking for a lively, outgoing feline companion. The Silver Bengal is a relatively new breed, developed in the 1980s by crossing Bengal cats with Siamese or Burmese cats. This combination resulted in a cat with distinctive Bengal spots, but with a silvery coat and green eyes.The breed has since been refined, developed, and is now recognized by many cat breeding organizations. The Silver Bengal has a lean, athletic build with a short, shiny coat that is soft to the touch. The coat is usually silver or light gray with dark spots or mottling. The eyes are large and expressive, usually a striking green color. The ears are large and pointed, and the tail is long and thin. Known for their playful and energetic personalities, these cats are perfect for families with children and those who enjoy an active lifestyle. An intelligent and curious cat, she loves to play with ... toys and explore ... surroundings. They are also very affectionate and enjoy spending time with their owners and are known for their sociable and outgoing personalities. It's important to note that the Silver Bengal Cat is a high-energy breed and needs plenty of play and exercise to stay healthy and happy. They also need regular grooming to keep their coat shiny and beautiful. Silver Bengal cats are generally healthy and hardy and live about 15 years. However, like all breeds, they can be prone to certain health problems such as ... dysplasia, heart disease, and kidney disease. Get your Silver Bengal cat from a reputable breeder who screens cats for these health problems. It is important to purchase In summary, the Silver Bengal is a beautiful and unique domestic cat breed known for its striking silver coat, green eyes and Bengal spots. These cats are playful, energetic, and affectionate, making them great companions for families and active individuals. However, they are very energetic cats and need plenty of exercise, play and regular grooming. It is important to buy from a reputable breeder who has screened your cat for health issues. Silver Bengal cat
• Re: Silver Bengal Cat   (ths store, 27.01.2023 15:46, 3.6 KBait)
  The Silver Bengal is a breed of domestic cat with a beautiful silvery coat, striking green eyes and distinctive Bengal spots. Known for their playful and energetic personalities, these cats make great companions for anyone looking for a lively, outgoing feline companion.
  The Silver Bengal cat is a relatively new breed developed in the 1980s by crossing Bengal cats with Siamese or Burmese cats. This combination resulted in a cat with distinctive Bengal spots, but with a silvery coat and green eyes.The breed has since been refined, developed, and is now recognized by many cat breeding organizations. The Silver Bengal has a lean, athletic build with a short, shiny coat that is soft to the touch. The coat is usually silver or light gray with dark spots or mottling. The eyes are large and expressive, usually a striking green color. The ears are large and pointed, and the tail is long and thin.
  Known for their playful and energetic personalities, these cats are perfect for families with children and those who enjoy an active lifestyle. An intelligent and curious cat, she loves to play with ... toys and explore ... surroundings. They are also very affectionate and enjoy spending time with their owners and are known for their sociable and outgoing personalities.
  It's important to note that the Silver Bengal Cat is a high-energy breed and needs plenty of play and exercise to stay healthy and happy. They also need regular grooming to keep their coats shiny and beautiful.
  Silver Bengal cats are generally healthy and hardy and live about 15 years. However, like all breeds, they can be prone to certain health problems such as ... dysplasia, heart disease, and kidney disease. Get your Silver Bengal cat from a reputable breeder who screens cats for these health problems. It is important to purchase
  In summary, the Silver Bengal is a beautiful and unique domestic cat breed known for its striking silver coat, green eyes and Bengal spots. These cats are playful, energetic, and affectionate, making them great companions for families and active individuals. However, they are very energetic cats and need plenty of exercise, play and regular grooming. It is important to buy from a reputable breeder who has screened your cat for health issues.