相信唔少人都聽過水星逆行，簡稱水逆🌊🌊噉其實咩係水逆呢？點解水星轉轉吓會逆行呢？水星逆行又會唔會令大家塞車遲到、有感情問題呢？🧐🧐
其實水星逆行係一種自然嘅天文現象🥸🥸水逆並非水星突然反方向公轉。事實上，地球同水星同樣係圍繞太陽逆時針方向公轉，水星圍繞太陽公轉一圈需要約8️⃣8️⃣地球日，而地球繞日公轉一圈需要約3️⃣6️⃣5️⃣地球日，所以其實水星公轉周期比地球公轉周期短🪁🪁我哋喺地球望上去，就會覺得水星對比起背景恆星（即係嗰啲幾百萬光年之外，望落去好似靜止不動嘅恆星🌌🌌）好似向後退緊，但其實只係因為水星行得快，超前咗地球😉😉
大家向左掃到第2️⃣頁會見到一段模擬動畫⏪⏪如果將企喺地球嘅觀察者同水星連成一線，並延伸至代表背景恆星嘅外圈，我哋可以見到喺外圈上嘅黃色軌跡由於兩者嘅公轉速度不同而出現「返兜」嘅情況🌀🌀依個就係水逆嘅原理，而依個現象每年大概會出現4️⃣次，錯覺每次大概會持續3️⃣星期。
暫時無科學證據證明水星逆行會令大家塞車死火🌝🌝不過住大西北嘅學術就建議無論順行逆行都好，有重要嘢做就早啲出門口🤣🤣希望大家下次聽到有人講水星逆行嘅時候，會記得箇中嘅原理啦🤪🤪
Have you heard of Mercury Retrograde? 🌊🌊 Astrologers believe that it causes you bad luck. You might be stuck in a traffic jam due to that. Is this true? Why would we see Mercury orbit in the opposite direction for a few weeks? 🧐🧐
Well, this is just an apparent retrograde motion observed from Earth.🥸🥸 The Mercury does not actually orbit in the opposite direction. The Mercury and the Earth both rotate anti-clockwise about the Sun with an orbital period of 8️⃣8️⃣ and 3️⃣6️⃣5️⃣ earth days respectively. Due to the difference in the orbital periods, Mercury would seem to be moving backward from Earth’s perspective, when in fact that is whenever Mercury surpasses the Earth.
Swipe left to page 2️⃣ for the virtual animation. ⏪⏪ Imagine if you connect two planets together with a straight line, you would then be able to track the movement of Mercury from the Earth’s perspective. As shown in the animation, the track in yellow shows a retrograde motion which is essentially due to the varying revolution speeds of the planets. Since Mercury orbits quicker🪁🪁, it laps Earth every 4 months, which is when the illusion occurs. 😉😉
There is no scientific evidence showing that the Mercury Retrograde leads you to a traffic jam. 🌝🌝 But it is always a good habit to have your feet on the floor some minutes earlier.🤣🤣 Wish you could recall the theory behind Mercury Retrograde the next time you hear someone says about it! 😉😉