1. 交点：轨道的取向表示为轨道平面相对于参考平面[通常为黄道(ecliptic)]的倾角(inclination)以及升交点(node)经度(从春分点到升交点的角距离. 天体在其轨道上的位置则决定于其偏近点角(anomaly),此位置作为时间的函数是从近重心点行程的时间来计算的.
1. 节;结;瘤
A node is a point, especially in the form of lump or swelling, where one thing joins another.
e.g. Cut them off cleanly through the stem just below the node.
就从茎节下面，沿茎干把它们全砍掉。
e.g. ...nerve nodes.
神经结
noun
1. (computer science) any computer that is hooked up to a computer network
2. any bulge or swelling of an anatomical structure or part
3. the source of lymph and lymphocytes
Synonym: lymph nodelymph gland
4. (astronomy) a point where an orbit crosses a plane
5. (physics) the point of minimum displacement in a periodic system
6. (botany) the small swelling that is the part of a plant stem from which one or more leaves emerge
Synonym: leaf node
7. any thickened enlargement
Synonym: knobthickening
8. a connecting point at which several lines come together