佇火星 ê 沙條崙

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：Striped Sand Dunes on Mars
• 影像來源：HiRISE, MRO, LPL (U. Arizona), NASA
• 影像處理：Włodek Głażewski
• 文稿：Alex R. Howe (NASA/USRA, Reader's History of SciFi Podcast)
• 台文翻譯：An-Li Tsai (NCU)

[漢羅] 佇火星 ê 沙條崙

火星面頂 ê 沙崙是按怎變做一條一條 ê？無人知影。這張 影像 是 tī 火星 ê Kunowsky 大坑 ê 沙條崙。是最近才用 火星探測軌道衛星 ê HiRISE kha-mé-lah 翕 ê。真濟火星 ê 沙崙去予二酸化炭素霜（to̍h 是 乾冰）崁牢矣！遮一搭遐一搭，才會看起來有的所在光、有的所在暗。二酸化炭素袂溶去，毋閣會 昇華 變做氣體。二酸化炭素是一个 溫室效應物質，就算伊是固體嘛是仝款。伊會 tī 冰 ê 形態 kā 熱量擋咧，才 úi 下面 昇華，造成像 歇陣噴泉彼款 ê 爆發。Tī 火星 ê 春天，這款爆發會造成沙崙 ê 烏斑，就是解凍了後看起來 較烏 ê 沙。這張 影像 是 tī 火星 ê 秋天翕 ê，彼當陣 ê 天氣已經欲變寒矣，這款一條一條 ê 圖樣煞予人捎攏無。一个假設是講，in 是冰 ê pit-sûn。是較弱 ê 爆發抑是日夜變化 ê 熱應力 造成 ê。毋閣這个講法猶袂確定。Tī 火星無仝 ê 季節 看遮 kah 別位 ê 沙崙，會使予咱較濟 ê 線索來拍開這个奧祕。

[POJ] Tī Hóe-chhiⁿ ê soa-tiâu-lûn

Hóe-chhiⁿ bīn-téng ê soa-lûn sī án-ná piàn-chò chi̍t-liâu chi̍t-liâu ê? Bô-lâng chai-iáⁿ. Chi̍t-tiuⁿ iáⁿ-siōng sī tī Hóe-chhiⁿ ê Kunowsky tōa-kheⁿ ê soa-tiâu-lûn. Sī chòe-kūn chiah iōng Hóe-chhiⁿ thàm-chhek-kúi-tō ūi-chhiⁿ ê HiRISE kha-mé-lah hip ê. Chin-chōe Hóe-chhiⁿ ê soa-lûn khì hō͘ jī-sng-hòa-thòaⁿ-sò͘-sng (to̍h sī kan-peng) khàm-tiâu ah! Chiah chi̍t-tah hiah chi̍t-tah, chiah-ē khòaⁿ--khí-lâi ū-ê só͘-chāi kng, ū-ê só͘-chāi àm. Jī-sng-hòa-thòaⁿ-sò͘ bē iûⁿ--khì, m̄-koh ē seng-hôa piàn-chò khì-thé. Jī-sng-hòa-thòaⁿ-sò͘ sī chi̍t-ê Un-sek-hāu-èng bu̍t-chit, tō-sǹg i sī kò͘-thé mā-sī kāng-khoán. I ē tī peng ê hêng-thài kā jia̍t-liōng tòng--ê, chiah úi ē-bīn seng-hôa, chō-sêng chhiūⁿ hioh-chūn phùn-choán hit-khoán ê po̍k-hoat. Tī Hóe-chhiⁿ ê chhun-thiⁿ, chi̍t-kóa po̍k-hoat ē chō-sêng soa-lûn ê o͘-pan, tō-sī kái-tòng liáu-āu khòaⁿ--khí-lâi khah o͘ ê soa. Chit-tiuⁿ iáⁿ-siōng sī tī Hóe-chhiⁿ ê chhiu-thiⁿ hip--ê, hit-tang-chūn ê thiⁿ-khì í-keng piàn-kôaⁿ ah, chi̍t-khoán chi̍t-liâu chi̍t-liâu ê tô͘-iūⁿ soah hō͘-lâng sa-lóng-bô. Chi̍t-ê ká-siat sī-kóng, in sī peng ê pit-sûn. Sī khah-jiok ê po̍k-hoat ia̍h-sī ji̍t-iā-piàn-hòa ê jia̍t-èng-le̍k chō-sêng ê. M̄-koh chit-ê kóng-hoat iáu-bē khak-tēng. Tī Hóe-chhiⁿ bô-kâng ê kùi-cheh khòaⁿ chiah kah pa̍t-ūi ê soa-lûn, ē-sái hō͘-lân khah-chōe ê sòaⁿ-soh lâi phah-khui chit-ê ò-pì.

[KIP] Tī Hué-tshinn ê sua-tiâu-lûn

Hué-tshinn bīn-tíng ê sua-lûn sī án-ná piàn-tsò tsi̍t-liâu tsi̍t-liâu ê? Bô-lâng tsai-iánn. Tsi̍t-tiunn iánn-siōng sī tī Hué-tshinn ê Kunowsky tuā-khenn ê sua-tiâu-lûn. Sī tsuè-kūn tsiah iōng Hué-tshinn thàm-tshik-kuí-tō uī-tshinn ê HiRISE kha-mé-lah hip ê. Tsin-tsuē Hué-tshinn ê sua-lûn khì hōo jī-sng-huà-thuànn-sòo-sng (to̍h sī kan-ping) khàm-tiâu ah! Tsiah tsi̍t-tah hiah tsi̍t-tah, tsiah-ē khuànn--khí-lâi ū-ê sóo-tsāi kng, ū-ê sóo-tsāi àm. Jī-sng-huà-thuànn-sòo bē iûnn--khì, m̄-koh ē sing-huâ piàn-tsò khì-thé. Jī-sng-huà-thuànn-sòo sī tsi̍t-ê Un-sik-hāu-ìng bu̍t-tsit, tō-sǹg i sī kòo-thé mā-sī kāng-khuán. I ē tī ping ê hîng-thài kā jia̍t-liōng tòng--ê, tsiah uí ē-bīn sing-huâ, tsō-sîng tshiūnn hioh-tsūn phùn-tsuán hit-khuán ê po̍k-huat. Tī Hué-tshinn ê tshun-thinn, tsi̍t-kuá po̍k-huat ē tsō-sîng sua-lûn ê oo-pan, tō-sī kái-tòng liáu-āu khuànn--khí-lâi khah oo ê sua. Tsit-tiunn iánn-siōng sī tī Hué-tshinn ê tshiu-thinn hip--ê, hit-tang-tsūn ê thinn-khì í-king piàn-kuânn ah, tsi̍t-khuán tsi̍t-liâu tsi̍t-liâu ê tôo-iūnn suah hōo-lâng sa-lóng-bô. Tsi̍t-ê ká-siat sī-kóng, in sī ping ê pit-sûn. Sī khah-jiok ê po̍k-huat ia̍h-sī ji̍t-iā-piàn-huà ê jia̍t-ìng-li̍k tsō-sîng ê. M̄-koh tsit-ê kóng-huat iáu-bē khak-tīng. Tī Hué-tshinn bô-kâng ê kuì-tseh khuànn tsiah kah pa̍t-uī ê sua-lûn, ē-sái hōo-lân khah-tsuē ê suànn-soh lâi phah-khui tsit-ê ò-pì.

[English] Striped Sand Dunes on Mars 

Why are these sand dunes on Mars striped? No one is sure. The featured image shows striped dunes in Kunowsky Crater on Mars, photographed recently with the Mars Reconnaissance Orbiter’s HiRISE Camera. Many Martian dunes are known to be covered unevenly with carbon dioxide ( dry ice ) frost, creating patterns of light and dark areas. Carbon dioxide doesn’t melt, but sublimates , turning directly into a gas.Carbon dioxide is also a greenhouse material even as a solid, so it can trap heat under the ice and sublimate from the bottom up, causing geyser-like eruptions . During Martian spring, these eruptions can cause a pattern of dark defrosting spots , where the darker sand is exposed. The featured image , though, was taken during Martian autumn, when the weather is getting colder – making these stripes particularly puzzling. One hypothesis is that they are caused by cracks in the ice that form from weaker eruptions or thermal stress as part of the day-night cycle, but research continues. Watching these dunes and others through more Martian seasons may give us more clues to solve this mystery.

詞彙學習