Glossary term: ग्रह

Description: इंटरनॅशनल ऍस्ट्रॉनॉमिकल युनियन नुसार ग्रह म्हणजे ताऱ्याभोवती किव्वा तार्याच्या अवशेषाभोवती कक्षेत फिरणारी खगोलीय वस्तू, जी स्वतःच्या गुरुत्वाकर्षण शक्तीने जवळजवळ गोलाकार होईल इतकी मोठी असू शकते, पण थर्मोन्यूक्लियर फ्यूजन होईल एवढी मोठी नाही. या खगोलीय वस्तूच्या गुरुत्वाकर्षणाने ऱ्यांच्या स्वतःच्या कक्षेत असणाऱ्या इतर खगोलीय वस्तू कक्षेतून निघाल्या पाहिजेत. या वस्तू जवळच्या सूर्याच्या प्रकाशाने चमकतात. त्यांना स्वतःचा प्रकाश नसतो, पण त्या इन्फ्रारेड तरंगलांबीमध्ये प्रकाश उत्सर्जित करतात. आपल्या सूर्यमालेत आठ ग्रह सूर्याभोवती फिरतात. ग्रह हे मुळात खडकाळ वस्तू असू शकतात, जसे की आतील ग्रह - बुध, शुक्र, पृथ्वी आणि मंगळ - किंवा मुख्यतः द्रव आणि वायू बाहेरील ग्रहांप्रमाणे लहान घन गाभा - गुरू, शनि, युरेनस आणि नेपच्यून. सूर्यमालेच्या बाहेरील ग्रहांना एक्स्ट्रासोलर ग्रह किंवा थोडक्यात एक्सोप्लॅनेट म्हणतात.

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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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