Wolf-Rayet 星 18 號 外圍 無對伨 ê 星雲

探索宇宙¹！逐工會揀一幅無仝款 ê 影像抑是相片，𤆬你熟似咱這个迷人 ê 宇宙，閣有專業天文學者²為你解說³。

• 原始文章：The Asymmetric Nebula Surrounding Wolf-Rayet Star 18
• 影像來源 kah 版權：Alex Woronow
• 台文翻譯：An-Li Tsai (NCU)

[漢羅] Wolf-Rayet 18 號星 外圍 無對伨 ê 星雲

是按怎 WR-18 星 ê 外圍星雲有一爿較光？ 這粒活跳 ê 星 嘛叫做 NGC 3199，伊 kah 伊外圍 ê 星雲攏 tī 南方 ê 航海星座 龍骨座 遐，離咱有 1 萬 2000 光年 遠。 這張深空影像 是經過足濟處理步數，才有法度看著氣泡形星雲內底，發光氣體 ê 雲絲細節。 這个星雲差不多有 75 光年闊。 星雲中心附近是 Wolf-Rayet 星 WR-18，伊是一粒大質量高溫短命 ê 恆星，會產生實密複雜 ê 恆星風。 實際上，因為 Wolf-Rayet 星 有足強 ê 恆星風，會 kā 邊仔 ê 星際物質 吹走，所以 in 會製造 外形看起來足趣味 ê 星雲。 像這个案例，咱本底叫是講，較光彼爿是因為這粒星 tī 齊齊 ê 媒介物內底 hôe–過 ê 時陣，產生 弓形震波，就 kah 一隻船行過 水面 ê 現象仝款。 毋過 最近 ê 測量分析 結果 表示，這粒星 並無 向 較光彼爿高速徙動。 所以這馬 ê 解說 變做 講，這粒星 ê 外圍物質毋是對伨–ê，較光 ê 彼爿較實密，而且是一簇一簇–ê。

[POJ] Wolf-Rayet 18 hō Chhiⁿ gōa-ûi bô tùi-thīn ê Seng-hûn

Sī án-ná WR-18 chhiⁿ ê gōa-ûi seng-hûn ū chi̍t pêng khah kng? Chit lia̍p oa̍h-thiàu ê chhiⁿ mā kiò-chò NGC 3199, i kah i gōa-ûi ê seng-hûn lóng tī lâm-hong ê hāng-hái seng-chō Lêng-kut-chō hiah, lī lán ū 1 bān 2000 kng-nî hn̄g. Chit tiuⁿ chhim-khong iáⁿ-siōng sī keng-kòe chiok chōe chhú-lí pō͘-sò͘, chiah ū hoat-tō͘ khòaⁿ tio̍h khì-phàu hêng seng-hûn lāi-té, hoat-kng khì-thé ê hûn-si sè-chiat. Chit ê seng-hûn chha-put-to ū 75 kng-nî khoah. Seng-hûn tiong-sim hū-kīn sī Wolf-Rayet chhiⁿ WR-18, i sī chi̍t lia̍p tōa-chit-liōng ko-un té-miā ê hêng-chhiⁿ, ē sán-seng cha̍t-ba̍t ho̍k-cha̍p ê hêng-chhiⁿ-hong. Si̍t-chè siōng, in-ūi Wolf-Rayet chhiⁿ ū chiok kiong ê hêng-chhiⁿ-hong, ē kā piⁿ-á ê seng-chè bu̍t-chit chhoe cháu, só͘-í in ē chè-chō gōa-hêng khòaⁿ–khí-lâi chiok chhù-bī ê seng-hûn. Chhiūⁿ chit ê àn-lē, lán pún-té kiò-sī kóng, khah kng hit-pêng sī in-ūi chit lia̍p chhiⁿ tī chiâu-chê ê mûi-kài-bu̍t lāi-té hôe–kòe ê sî-chūn, sán-seng keng-hêng chìn-pho, to̍h kah chi̍t chiah chûn kiâⁿ kòe chúi-bīn ê hiān-siōng kāng-khoán. M̄-koh chòe-kīn ê chhek-liông hun-sek kiat-kò͘ piáu-sī, chit lia̍p chhiⁿ pēng bô hiòng khah kng hit-pêng ko-sok sóa-tāng. Só͘-í chit-má ê kái-soeh piàn-chò kóng, chit lia̍p chhiⁿ ê gōa-ûi bu̍t-chit m̄-sī tùi-thīn–ê, khah kng ê hit-pêng khah cha̍t-ba̍t, jî-chhiáⁿ sī chi̍t-chhok chi̍t-chhok–ê.

[KIP] Wolf-Rayet 18 hō Tshinn guā-uî bô tuì-thīn ê Sing-hûn

Sī án-ná WR-18 tshinn ê guā-uî sing-hûn ū tsi̍t pîng khah kng? Tsit lia̍p ua̍h-thiàu ê tshinn mā kiò-tsò NGC 3199, i kah i guā-uî ê sing-hûn lóng tī lâm-hong ê hāng-hái sing-tsō Lîng-kut-tsō hiah, lī lán ū 1 bān 2000 kng-nî hn̄g. Tsit tiunn tshim-khong iánn-siōng sī king-kuè tsiok tsuē tshú-lí pōo-sòo, tsiah ū huat-tōo khuànn tio̍h khì-phàu hîng sing-hûn lāi-té, huat-kng khì-thé ê hûn-si sè-tsiat. Tsit ê sing-hûn tsha-put-to ū 75 kng-nî khuah. Sing-hûn tiong-sim hū-kīn sī Wolf-Rayet tshinn WR-18, i sī tsi̍t lia̍p tuā-tsit-liōng ko-un té-miā ê hîng-tshinn, ē sán-sing tsa̍t-ba̍t ho̍k-tsa̍p ê hîng-tshinn-hong. Si̍t-tsè siōng, in-uī Wolf-Rayet tshinn ū tsiok kiong ê hîng-tshinn-hong, ē kā pinn-á ê sing-tsè bu̍t-tsit tshue tsáu, sóo-í in ē tsè-tsō guā-hîng khuànn–khí-lâi tsiok tshù-bī ê sing-hûn. Tshiūnn tsit ê àn-lē, lán pún-té kiò-sī kóng, khah kng hit-pîng sī in-uī tsit lia̍p tshinn tī tsiâu-tsê ê muî-kài-bu̍t lāi-té huê–kuè ê sî-tsūn, sán-sing king-hîng tsìn-pho, to̍h kah tsi̍t tsiah tsûn kiânn kuè tsuí-bīn ê hiān-siōng kāng-khuán. M̄-koh tsuè-kīn ê tshik-liông hun-sik kiat-kòo piáu-sī, tsit lia̍p tshinn pīng bô hiòng khah kng hit-pîng ko-sok suá-tāng. Sóo-í tsit-má ê kái-sueh piàn-tsò kóng, tsit lia̍p tshinn ê guā-uî bu̍t-tsit m̄-sī tuì-thīn–ê, khah kng ê hit-pîng khah tsa̍t-ba̍t, jî-tshiánn sī tsi̍t-tshok tsi̍t-tshok–ê.

[English] The Asymmetric Nebula Surrounding Wolf-Rayet Star 18

Why does the nebula around the star WR-18 shine brighter on one side? Also known as NGC 3199, this active star and its surrounding nebula lie about 12,000 light-years away toward the nautical southern constellation of Carina. The featured deep image has been highly processed to bring out filamentary details of the glowing gas in the bubble-shaped nebula. The nebula is about 75 light-years across. Near the nebula’s center is a Wolf-Rayet star, WR-18, which is a massive, hot, short-lived star that generates an intense and complex stellar wind. In fact, Wolf-Rayet stars are known to create nebulas with interesting shapes as their powerful winds sweep up surrounding interstellar material. In this case, the bright right edge was initially thought to indicate that a bow shock was being produced as the star plowed through a uniform medium, like a boat through water. Recent measurements and analyses, however, have shown the star is not moving quickly toward the bright edge. A more likely explanation has emerged that the material surrounding the star is not uniform, but clumped and denser near the bright edge.

詞彙學習（漢羅/POJ/KIP/華語/English）

• 【Wolf-Rayet 星】Wolf-Rayet chhiⁿ/Wolf-Rayet tshinn/沃爾夫-拉葉星/Wolf-Rayet star
• 【WR-18】WR cha̍p-peh/WR tsa̍p-peh/WR-18/WR-18
• 【NGC 3199】NGC sam-it-kiú-kiú/NGC sam-it-kiú-kiú/NGC 3199/NGC 3199
• 【龍骨座】Lêng-kut-chō/Lîng-kut-tsō/船底座/Carina
• 【船底座】Chûn-té-chō/Tsûn-té-tsō/船底座/Carina
• 【雲絲】hûn-si/hûn-si/絲狀物/filament
• 【星雲】seng-hûn/sing-hûn/星雲/nebula
• 【恆星風】hêng-chhiⁿ-hong/hîng-tshinn-hong/恆星風/stellar wind
• 【媒介物】mûi-kài-bu̍t/king-hîng tsìn-pho/介質/medium
• 【弓形震波】keng-hêng chìn-pho/king-hîng tsìn-pho/弓形震波/bow shock
• 【對伨】tùi-thīn/tuì-thīn/對稱/uniform
• 【無對伨】bô tùi-thīn/bô tuì-thīn/不對稱/asymmetric