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- العبور الشمسي هو حركة لأي جسم يمر بين الشمس والأرض. وهذا يشمل أساسا الكواكب عطارد والزهرة. كسف الشمس هو أيضًا عبور شمسي للقمر، ولكنه تقنيًا فقط إذا كان لا يغطي القرص الكامل للشمس (كسوف حلقي)، حيث أن «النقل» لا يعد سوى كائنات أصغر حجمًا مما تمر أمامه.. النقل الشمسي هو واحد من عدة أنواع من العبور الفلكي. يحدث أيضًا نقل الطاقة الشمسية (ويسمى أيضًا انقطاع الطاقة الشمسية، وأحيانًا التلاشي الشمسي، أو انقطاع الشمس، أو تلاشي الشمس) في سواتل الاتصالات التي تمر أمام الشمس لعدة دقائق يوميًا لعدة أيام متواصلة لفترة في الأشهر القريبة الاعتدالات، التواريخ الدقيقة حسب مكان القمر الصناعي في السماء بالنسبة لمحطته الأرضية. لأن الشمس تنتج أيضاً كمية كبيرة من إشعاع الميكروويف بالإضافة إلى أشعة الشمس، فإنها تغمر الإشارات اللاسلكية للميكروويف الصادرة من مرسلات الإرسال عبر الأقمار الصناعية. ويسبب هذا التداخل الكهرومغناطيسي الهائل انقطاعات في خدمات الأقمار الصناعية الثابتة التي تستخدم أطباق استقبال الأقمار الصناعية، بما في ذلك شبكات التلفزيون والشبكات ، فضلاً عن للمحطات الطرفية VSAT (ar)
- In astronomy, a solar transit is a movement of any object passing between the Sun and the Earth. This mainly includes the planets Mercury and Venus. A solar eclipse is also a solar transit of the Moon, but technically only if it does not cover the entire disc of the Sun (an annular eclipse), as "transit" counts only objects that are smaller than what they are passing in front of. Solar transit is only one of several types of astronomical transit. A solar transit (also called a solar outage, sometimes solar fade, sun outage, or sun fade) also occurs to communications satellites, which pass in front of the Sun for several minutes each day for several days straight for a period in the months around the equinoxes, the exact dates depending on where the satellite is in the sky relative to its earth station. Because the Sun also produces a great deal of microwave radiation in addition to sunlight, it overwhelms the microwave radio signals coming from the satellite's transponders. This enormous electromagnetic interference causes interruptions in fixed satellite services that use satellite dishes, including TV networks and radio networks, as well as VSAT and DBS. Only downlinks from the satellite are affected, uplinks from the Earth are normally not, as the planet "shades" the Earth station when viewed from the satellite. Satellites in geosynchronous orbit are irregularly affected based on their inclination. Reception from satellites in other orbits are frequently but only momentarily affected by this, and by their nature the same signal is usually repeated or relayed on another satellite, if a tracking dish is used at all. Satellite radio and other services like GPS are not affected, as they use no receiving dish, and therefore do not concentrate the interference. (GPS and certain satellite radio systems use non-geosynchronous satellites.) Solar transit begins with only a brief degradation in signal quality for a few moments. At the same time each day, for the next several days, it gets longer and gets worse, until finally gradually improving after several more days. For digital satellite services, the cliff effect will eliminate reception entirely at a given threshold. Reception is typically lost for only a few minutes on the worst day, but the beam width of the dish can affect this. Signal strength also affects this, as does the bandwidth of the signal. If the power is concentrated into a narrower band, there is a higher signal-to-noise ratio. If the same signal is spread wider, the receiver also gets a wider swath of noise, degrading reception. The exact days and times of solar transit outages, for each satellite and for each receiving point (Earth station) on the Earth, are available at various websites. For broadcast networks, the must be pre-recorded, replaced with local programming, fed via another satellite in a different orbital position, or fed via another method entirely during these times. In the Northern Hemisphere, solar transit is usually in early March and October. In the Southern Hemisphere, solar transit is usually in early September and April. The time of day varies mainly with the longitude of the satellite and receiving station, while the exact days vary mainly with the station's latitude. Stations along the equator will experience solar transit right at the equinoxes, as that is where geostationary satellites are located directly over. Note that with large dishes, it would be possible for the feedhorn to be damaged, which is prevented by the parabolic dishes having a flat (non-glossy) finish that does not focus light or heat effectively. Non-parabolic dishes are not susceptible as they cannot focus in this manner. (en)
- 太陽面通過（たいようめんつうか）とは、ある天体にいる観測者から見て、見かけ上太陽の表面を別の天体が通過する現象である。日面通過（にちめんつうか）や日面経過（にちめんけいか）、太陽面経過とも呼ばれる。普通、地球から見て内惑星である水星または金星が太陽の表面を通過する現象のことを指す。これは太陽と内惑星と地球が一直線に並んだときに見られるもので、地球では水星と金星でのみみられる天体現象である。水星、金星は太陽に比べ大きさがかなり小さいので小さな黒い点がゆっくり太陽の表面を移動していく形で観測される。 ヨハネス・ケプラーは、1627年に初めて金星の太陽面通過が1631年12月6日に起こると予想した（実際に起きたのは12月7日）。 (ja)
- 凌日（solar transit；solar outage、solar fade、sun outage、sun fade）是一種天文現象，通常指有地內行星（金星或水星）從地球與太陽之間經過，在地球上的觀察者會發現有一個黑點從太陽通過，持續一個多小時，稱為凌日。而在地球之外的其他行星，除了水星之外，同樣也可觀測到其內側行星的凌日。 目前在地球上可觀測到的凌日現象有金星凌日和水星凌日，德國天文學家開普勒在1629年預言：“1631年11月7日將發生水星凌日。”是人類天文史上第一次預言成功的例子。 太陽系外行星也有些是以觀測母恆星光度變化，確認凌日發生，光度降低而被發現。 (zh)
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