He̍k-chheⁿ

Tē-kiû sī chi̍t lia̍p he̍k-chheⁿ.

He̍k-chheⁿ, thian-thé chi̍t khoán, in kho͘ chhin-chhiūⁿ Ji̍t-thâu hit khoán hêng-chheⁿ kiâⁿ-sóa, ka-tī bô pàng chhut la̍t-thâu (energy). Kho-ha̍k-kài ū chi̍t kóa koh khah giâm-keh ê tēng-gī, nā chiàu Kok-chè Thian-bûn-ha̍k Liân-ha̍p (International Astronomical Union) koat-tēng ê hun-lūi, chit-liōng ū kàu gia̍h, hêng-thé óa îⁿ kiû khoán, pún-sin koh m̄-sī ōe-chheⁿ, só͘ kiâⁿ ê kúi-tō téng-bīn bô chhun sè-lia̍p mi̍h kap chhùi-iú-á, chiah sī he̍k-chheⁿ.

Chham-chiàu

• "What Is a Planet?". SPACE.com
• "Planet" Encyclopaedia Britannica.