Moon phases and eclipses

Kuma da watã bãbu karkacewa gare shi. Rabinsa yana da haske daga rana; abin da yake canjawa shi ne, ko da yaushe rabin wannan haske yana fuskantar ku. Idan kun ga me ya sa, eclipses daina zama wani sihiri kuma fara da za a iya hasashen.

Kuma da dare, kuma da rana. Waɗannan mataki ne kawai na ra’ayinmu.

Look

Kuma da watã bã ya yin haske a kansa. Yana haske ne dõmin hasken rãnã ya fãɗi a kansa. A cikin wannan yanayi, rana tana da haske a tsakiyar dare kuma ta yi duhu a tsakiyar rana, kamar yadda rana ke da haske a tsakiyar dare.

Kuma idan wata ya yi tafiya a cikin ƙasa, sai mu ga bambancin girman rabinsa mai haske da rãnã:

• Yana da wata: watan yana tsakanin ƙasa da rana. Kuma rãfi mai haske yanã kange daga gare mu, sabõda haka bã mu ganinsa.
• Fifth quarter: muna ganin rabin na’urar da aka kunna.
• Fulawa Mai Ciki: Duniya tana tsakanin rana da wata. Munã ganin rabin haske gaba ɗaya.
• Last quarter: rabin haske a sake, gefen da ke gaba.

A cikin kayan aiki, hoton hagu yana kallo ƙasa a kan ƙasa da wata daga sama, tare da rana a gefen hagu. The right picture shows what you see from Earth. Motsa slider kuma ka duba sauyinsu biyu tare.

A lõkacin da rãnã da ƙasa da watã suke daidaitãwa.

• A solar eclipse happens when the moon’s shadow falls on Earth at new Moon.
• A lunar eclipse yana faruwa lokacin da inuwa ta ƙasa ke kama da wata a lokacin watan cikakke.

Understand

The Moon goes once around Earth, measured against the stars, in 27.3 days (the sidereal month). But the phases repeat every 29.5 days (the synodic month). To, mẽne ne bambanci? While the Moon goes around Earth, Earth moves about 1/12 of the way around the Sun. Kuma da dare, sai ya kasance mai girman gaske.

Cikin kashi na diski wanda yake nuna haske yana dogara da gefen tsakanin rana da wata kamar yadda ake gani daga ƙasa, ana kiransa elongation:

Elongation	Phase	Lit fraction
0°	Dakata	0%
90°	First quarter	50%
180°	Full Moon	100%
270°	Last quarter	50%

Kuma idan wata ya yi tafiya a cikin wani yanki kamar yadda ƙasa take tafiya a cikin wani yanki, to, zã mu sãmi gushewar rãnã a kõwane wata mai zuwa kuma gushewar watã a kõwane watan cikakke. Kuma da watã yanã karkata daga daidaita. 5.1 digiri. Kuma idan haske ya yi tsawo, sai wata ta bayyana a samansa.

An kira wurare biyu inda orbit na wata ke haɗuwa da jirgin orbit na ƙasa nodes. Kuma idan wata rana ta yi tsawo, sai a yi ta yin girgije. Wannan yana faruwa a cikin “musumiyar eclipse” biyu kowace shekara, kusan watanni shida daga juna.

Master

The illuminated fraction k follows from the phase angle i (the Sun-Moon-Earth angle):

k = (1 + cos i) / 2

Kuma idan aka yi la’akari da cewa rana tana kusa da wata sau 390, i ≈ 180° − elongation. Shirin kayan aiki na lissafa i tare da jerin Meeus (Astronomical Algorithms, eq. 48.4), wanda ke gyaran tsawo na tsakiyar gami da muhimman kalmomin lokaci na orbits na watan da rana. Kuma lalle ne, haƙĩƙa, Allah Ya saukar da Littãfi mai bayyanãwa a cikin Alƙur’ani, da hikima.

A watan synodic ya biyo daga biyu angulated gudu: 1/P_syn = 1/P_sid − 1/P_year = 1/27.3217 − 1/365.256, ba da 29.531 kwanaki.

Ko dai wata fashewa ta yiwu tana dogara da argument na latitude F, gefenta daga node mai tashi. Meeus ya ba da wani tsari na sauri: a lokacin wata mai zuwa ko kuma cikakke, idan |sin F| > 0.36 (F fiye da kusan 21° daga wani node), to babu wata eclipse. The tool applies exactly this test. Wannan wani yanayi ne mai muhimmanci, ba wani hasashen irin girgizar kasa ko inda za a iya gani ba: wannan yana bukatar nisan wata, geometry na inuwa ta ƙasa da wurare masu daidaito.

An hana canzawa. Sun yi tafiya a baya-bayan nan a kan ecliptic sau daya kowace 18.6 shekaru, wanda shi ne dalilin da ya sa eclipse lokacin da suka zo game da 19 kwanaki da suka gabata a kowane shekara, kuma wani ɓangare na dalilin da ya sa eclipses sake a cikin shahararren 18-shekara saros tsari.