Glossary term: कक्षा

Description: कक्षा किसी प्रणाली में किसी वस्तु के द्रव्यमान के केंद्र के चारों ओर घूमने का पथ है, जो प्रणाली में वस्तुओं के बीच पारस्परिक गुरुत्वाकर्षण बल के कारण होता है। सौर मंडल जैसी प्रणालियों के लिए, जहां केंद्रीय भाग अन्य पिंडों की तुलना में बहुत बड़ा है, द्रव्यमान का यह केंद्र सबसे बड़ी वस्तु के अंदर या उसके निकट है (सौर मंडल, सूर्य के मामले में)। एक द्विआधारी तारा प्रणाली में, तारे की कक्षा के द्रव्यमान का केंद्र अक्सर दो तारों के बीच होता है।

कक्षाएँ आम तौर पर अण्डाकार होती हैं, और सिस्टम के द्रव्यमान का केंद्र दीर्घवृत्त के केंद्रों में से एक पर स्थित होता है। कक्षा का आयतन और आकार अर्धप्रमुख अक्ष और दीर्घवृत्त की विलक्षणता द्वारा परिभाषित किया गया है। अधिक विलक्षण कक्षाओं में बहुत अधिक अण्डाकार विलक्षणताएँ होती हैं। सौर मंडल के अधिकांश ग्रहों की कक्षीय विलक्षणताएं शून्य के बहुत करीब हैं, उदाहरण के लिए, शुक्र (0.007), पृथ्वी (0.017), बुध (0.206) और बौना ग्रह प्लूटो (0.244)।

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Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".

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