Get quick answers to your questions about the article from our AI researcher chatbot
{'id': 'https://openalex.org/W2024785675', 'doi': 'https://doi.org/10.1086/321552', 'title': 'A Pair of Resonant Planets Orbiting GJ 876', 'display_name': 'A Pair of Resonant Planets Orbiting GJ 876', 'publication_year': 2001, 'publication_date': '2001-07-20', 'ids': {'openalex': 'https://openalex.org/W2024785675', 'doi': 'https://doi.org/10.1086/321552', 'mag': '2024785675'}, 'language': 'en', 'primary_location': {'is_oa': True, 'landing_page_url': 'https://doi.org/10.1086/321552', 'pdf_url': 'https://iopscience.iop.org/article/10.1086/321552/pdf', 'source': {'id': 'https://openalex.org/S1980519', 'display_name': 'The Astrophysical Journal', 'issn_l': '0004-637X', 'issn': ['0004-637X', '1538-4357'], 'is_oa': True, 'is_in_doaj': True, 'is_core': True, 'host_organization': 'https://openalex.org/P4310320083', 'host_organization_name': 'IOP Publishing', 'host_organization_lineage': ['https://openalex.org/P4310311669', 'https://openalex.org/P4310320083'], 'host_organization_lineage_names': ['Institute of Physics', 'IOP Publishing'], 'type': 'journal'}, 'license': None, 'license_id': None, 'version': 'publishedVersion', 'is_accepted': True, 'is_published': True}, 'type': 'article', 'type_crossref': 'journal-article', 'indexed_in': ['crossref'], 'open_access': {'is_oa': True, 'oa_status': 'bronze', 'oa_url': 'https://iopscience.iop.org/article/10.1086/321552/pdf', 'any_repository_has_fulltext': False}, 'authorships': [{'author_position': 'first', 'author': {'id': 'https://openalex.org/A5044287511', 'display_name': 'Geoffrey W. Marcy', 'orcid': 'https://orcid.org/0000-0002-2909-0113'}, 'institutions': [{'id': 'https://openalex.org/I95457486', 'display_name': 'University of California, Berkeley', 'ror': 'https://ror.org/01an7q238', 'country_code': 'US', 'type': 'education', 'lineage': ['https://openalex.org/I95457486']}], 'countries': ['US'], 'is_corresponding': False, 'raw_author_name': 'Geoffrey W. Marcy', 'raw_affiliation_strings': ['Department of Astronomy, University of California, Berkeley, CA 94720'], 'affiliations': [{'raw_affiliation_string': 'Department of Astronomy, University of California, Berkeley, CA 94720', 'institution_ids': ['https://openalex.org/I95457486']}]}, {'author_position': 'middle', 'author': {'id': 'https://openalex.org/A5036091587', 'display_name': 'R. Paul Butler', 'orcid': 'https://orcid.org/0000-0003-1305-3761'}, 'institutions': [{'id': 'https://openalex.org/I196817621', 'display_name': 'Carnegie Institution for Science', 'ror': 'https://ror.org/04jr01610', 'country_code': 'US', 'type': 'nonprofit', 'lineage': ['https://openalex.org/I196817621']}, {'id': 'https://openalex.org/I4210124388', 'display_name': 'Carnegie Observatories', 'ror': 'https://ror.org/03h4zjr91', 'country_code': 'US', 'type': 'facility', 'lineage': ['https://openalex.org/I196817621', 'https://openalex.org/I4210124388']}], 'countries': ['US'], 'is_corresponding': False, 'raw_author_name': 'R. Paul Butler', 'raw_affiliation_strings': ['Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC. 20015-1305'], 'affiliations': [{'raw_affiliation_string': 'Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC. 20015-1305', 'institution_ids': ['https://openalex.org/I196817621', 'https://openalex.org/I4210124388']}]}, {'author_position': 'middle', 'author': {'id': 'https://openalex.org/A5016310949', 'display_name': 'Debra A. Fischer', 'orcid': 'https://orcid.org/0000-0003-2221-0861'}, 'institutions': [{'id': 'https://openalex.org/I95457486', 'display_name': 'University of California, Berkeley', 'ror': 'https://ror.org/01an7q238', 'country_code': 'US', 'type': 'education', 'lineage': ['https://openalex.org/I95457486']}], 'countries': ['US'], 'is_corresponding': False, 'raw_author_name': 'Debra Fischer', 'raw_affiliation_strings': ['Department of Astronomy, University of California, Berkeley, CA 94720'], 'affiliations': [{'raw_affiliation_string': 'Department of Astronomy, University of California, Berkeley, CA 94720', 'institution_ids': ['https://openalex.org/I95457486']}]}, {'author_position': 'middle', 'author': {'id': 'https://openalex.org/A5078287056', 'display_name': 'Steven S. Vogt', 'orcid': 'https://orcid.org/0000-0001-7177-7456'}, 'institutions': [{'id': 'https://openalex.org/I185103710', 'display_name': 'University of California, Santa Cruz', 'ror': 'https://ror.org/03s65by71', 'country_code': 'US', 'type': 'education', 'lineage': ['https://openalex.org/I185103710']}, {'id': 'https://openalex.org/I196817621', 'display_name': 'Carnegie Institution for Science', 'ror': 'https://ror.org/04jr01610', 'country_code': 'US', 'type': 'nonprofit', 'lineage': ['https://openalex.org/I196817621']}, {'id': 'https://openalex.org/I4210124388', 'display_name': 'Carnegie Observatories', 'ror': 'https://ror.org/03h4zjr91', 'country_code': 'US', 'type': 'facility', 'lineage': ['https://openalex.org/I196817621', 'https://openalex.org/I4210124388']}], 'countries': ['US'], 'is_corresponding': False, 'raw_author_name': 'Steven S. Vogt', 'raw_affiliation_strings': ['Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington DC 20015-1305', 'UCO/Lick Observatory, University of California at Santa Cruz, Santa Cruz, CA 95064'], 'affiliations': [{'raw_affiliation_string': 'UCO/Lick Observatory, University of California at Santa Cruz, Santa Cruz, CA 95064', 'institution_ids': ['https://openalex.org/I185103710']}, {'raw_affiliation_string': 'Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington DC 20015-1305', 'institution_ids': ['https://openalex.org/I196817621', 'https://openalex.org/I4210124388']}]}, {'author_position': 'middle', 'author': {'id': 'https://openalex.org/A5082738869', 'display_name': 'Jack J. Lissauer', 'orcid': 'https://orcid.org/0000-0001-6513-1659'}, 'institutions': [{'id': 'https://openalex.org/I1280536761', 'display_name': 'Ames Research Center', 'ror': 'https://ror.org/02acart68', 'country_code': 'US', 'type': 'facility', 'lineage': ['https://openalex.org/I1280536761', 'https://openalex.org/I4210124779']}], 'countries': ['US'], 'is_corresponding': False, 'raw_author_name': 'Jack J. Lissauer', 'raw_affiliation_strings': ['NASA Ames Research Center, Space Science Division, MS245-3, Moffett Field, CA 94035-1000'], 'affiliations': [{'raw_affiliation_string': 'NASA Ames Research Center, Space Science Division, MS245-3, Moffett Field, CA 94035-1000', 'institution_ids': ['https://openalex.org/I1280536761']}]}, {'author_position': 'last', 'author': {'id': 'https://openalex.org/A5110289653', 'display_name': 'Eugenio J. Rivera', 'orcid': None}, 'institutions': [{'id': 'https://openalex.org/I59553526', 'display_name': 'Stony Brook University', 'ror': 'https://ror.org/05qghxh33', 'country_code': 'US', 'type': 'education', 'lineage': ['https://openalex.org/I59553526']}, {'id': 'https://openalex.org/I1327163397', 'display_name': 'State University of New York', 'ror': 'https://ror.org/01q1z8k08', 'country_code': 'US', 'type': 'education', 'lineage': ['https://openalex.org/I1327163397']}, {'id': 'https://openalex.org/I1280536761', 'display_name': 'Ames Research Center', 'ror': 'https://ror.org/02acart68', 'country_code': 'US', 'type': 'facility', 'lineage': ['https://openalex.org/I1280536761', 'https://openalex.org/I4210124779']}], 'countries': ['US'], 'is_corresponding': False, 'raw_author_name': 'Eugenio J. Rivera', 'raw_affiliation_strings': ['Also at the Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, NY 11794-3800', 'NASA Ames Research Center, Space Science Division, MS245-3, Moffett Field, CA 94035-1000'], 'affiliations': [{'raw_affiliation_string': 'Also at the Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, NY 11794-3800', 'institution_ids': ['https://openalex.org/I59553526', 'https://openalex.org/I1327163397']}, {'raw_affiliation_string': 'NASA Ames Research Center, Space Science Division, MS245-3, Moffett Field, CA 94035-1000', 'institution_ids': ['https://openalex.org/I1280536761']}]}], 'institution_assertions': [], 'countries_distinct_count': 1, 'institutions_distinct_count': 7, 'corresponding_author_ids': [], 'corresponding_institution_ids': [], 'apc_list': {'value': 4499, 'currency': 'USD', 'value_usd': 4499, 'provenance': 'doaj'}, 'apc_paid': None, 'fwci': 14.755, 'has_fulltext': True, 'fulltext_origin': 'ngrams', 'cited_by_count': 376, 'citation_normalized_percentile': {'value': 0.999925, 'is_in_top_1_percent': True, 'is_in_top_10_percent': True}, 'cited_by_percentile_year': {'min': 98, 'max': 99}, 'biblio': {'volume': '556', 'issue': '1', 'first_page': '296', 'last_page': '301'}, 'is_retracted': False, 'is_paratext': False, 'primary_topic': {'id': 'https://openalex.org/T10039', 'display_name': 'Stellar, planetary, and galactic studies', 'score': 0.9999, 'subfield': {'id': 'https://openalex.org/subfields/3103', 'display_name': 'Astronomy and Astrophysics'}, 'field': {'id': 'https://openalex.org/fields/31', 'display_name': 'Physics and Astronomy'}, 'domain': {'id': 'https://openalex.org/domains/3', 'display_name': 'Physical Sciences'}}, 'topics': [{'id': 'https://openalex.org/T10039', 'display_name': 'Stellar, planetary, and galactic studies', 'score': 0.9999, 'subfield': {'id': 'https://openalex.org/subfields/3103', 'display_name': 'Astronomy and Astrophysics'}, 'field': {'id': 'https://openalex.org/fields/31', 'display_name': 'Physics and Astronomy'}, 'domain': {'id': 'https://openalex.org/domains/3', 'display_name': 'Physical Sciences'}}, {'id': 'https://openalex.org/T10325', 'display_name': 'Astro and Planetary Science', 'score': 0.9997, 'subfield': {'id': 'https://openalex.org/subfields/3103', 'display_name': 'Astronomy and Astrophysics'}, 'field': {'id': 'https://openalex.org/fields/31', 'display_name': 'Physics and Astronomy'}, 'domain': {'id': 'https://openalex.org/domains/3', 'display_name': 'Physical Sciences'}}, {'id': 'https://openalex.org/T10477', 'display_name': 'Astrophysics and Star Formation Studies', 'score': 0.9996, 'subfield': {'id': 'https://openalex.org/subfields/3103', 'display_name': 'Astronomy and Astrophysics'}, 'field': {'id': 'https://openalex.org/fields/31', 'display_name': 'Physics and Astronomy'}, 'domain': {'id': 'https://openalex.org/domains/3', 'display_name': 'Physical Sciences'}}], 'keywords': [{'id': 'https://openalex.org/keywords/outer-planets', 'display_name': 'Outer planets', 'score': 0.69860524}, {'id': 'https://openalex.org/keywords/eccentricity', 'display_name': 'Eccentricity (behavior)', 'score': 0.66379577}, {'id': 'https://openalex.org/keywords/orbital-elements', 'display_name': 'Orbital elements', 'score': 0.52226454}, {'id': 'https://openalex.org/keywords/orbital-inclination', 'display_name': 'Orbital inclination', 'score': 0.49034286}, {'id': 'https://openalex.org/keywords/celestial-mechanics', 'display_name': 'Celestial mechanics', 'score': 0.48966888}, {'id': 'https://openalex.org/keywords/mean-motion', 'display_name': 'Mean motion', 'score': 0.4717299}, {'id': 'https://openalex.org/keywords/orbital-mechanics', 'display_name': 'Orbital mechanics', 'score': 0.45371896}, {'id': 'https://openalex.org/keywords/elliptic-orbit', 'display_name': 'Elliptic orbit', 'score': 0.42561805}], 'concepts': [{'id': 'https://openalex.org/C121332964', 'wikidata': 'https://www.wikidata.org/wiki/Q413', 'display_name': 'Physics', 'level': 0, 'score': 0.9374803}, {'id': 'https://openalex.org/C51244244', 'wikidata': 'https://www.wikidata.org/wiki/Q634', 'display_name': 'Planet', 'level': 2, 'score': 0.8534107}, {'id': 'https://openalex.org/C2777377174', 'wikidata': 'https://www.wikidata.org/wiki/Q544', 'display_name': 'Outer planets', 'level': 3, 'score': 0.69860524}, {'id': 'https://openalex.org/C190538878', 'wikidata': 'https://www.wikidata.org/wiki/Q50013', 'display_name': 'Eccentricity (behavior)', 'level': 2, 'score': 0.66379577}, {'id': 'https://openalex.org/C58142911', 'wikidata': 'https://www.wikidata.org/wiki/Q3863', 'display_name': 'Asteroid', 'level': 2, 'score': 0.6007953}, {'id': 'https://openalex.org/C125311221', 'wikidata': 'https://www.wikidata.org/wiki/Q208474', 'display_name': 'Orbital eccentricity', 'level': 3, 'score': 0.54850537}, {'id': 'https://openalex.org/C1276947', 'wikidata': 'https://www.wikidata.org/wiki/Q333', 'display_name': 'Astronomy', 'level': 1, 'score': 0.5484635}, {'id': 'https://openalex.org/C44870925', 'wikidata': 'https://www.wikidata.org/wiki/Q37547', 'display_name': 'Astrophysics', 'level': 1, 'score': 0.5312108}, {'id': 'https://openalex.org/C97784730', 'wikidata': 'https://www.wikidata.org/wiki/Q272626', 'display_name': 'Orbital elements', 'level': 2, 'score': 0.52226454}, {'id': 'https://openalex.org/C10632323', 'wikidata': 'https://www.wikidata.org/wiki/Q4112212', 'display_name': 'Orbital inclination', 'level': 3, 'score': 0.49034286}, {'id': 'https://openalex.org/C27638517', 'wikidata': 'https://www.wikidata.org/wiki/Q184274', 'display_name': 'Celestial mechanics', 'level': 2, 'score': 0.48966888}, {'id': 'https://openalex.org/C197464742', 'wikidata': 'https://www.wikidata.org/wiki/Q1720536', 'display_name': 'Mean motion', 'level': 3, 'score': 0.4717299}, {'id': 'https://openalex.org/C6629501', 'wikidata': 'https://www.wikidata.org/wiki/Q842433', 'display_name': 'Orbital mechanics', 'level': 3, 'score': 0.45371896}, {'id': 'https://openalex.org/C100905312', 'wikidata': 'https://www.wikidata.org/wiki/Q206717', 'display_name': 'Planetary system', 'level': 3, 'score': 0.44709557}, {'id': 'https://openalex.org/C139210041', 'wikidata': 'https://www.wikidata.org/wiki/Q2145840', 'display_name': 'Resonance (particle physics)', 'level': 2, 'score': 0.42755312}, {'id': 'https://openalex.org/C173990265', 'wikidata': 'https://www.wikidata.org/wiki/Q2268240', 'display_name': 'Elliptic orbit', 'level': 2, 'score': 0.42561805}, {'id': 'https://openalex.org/C184779094', 'wikidata': 'https://www.wikidata.org/wiki/Q26383', 'display_name': 'Atomic physics', 'level': 1, 'score': 0.08752826}, {'id': 'https://openalex.org/C19269812', 'wikidata': 'https://www.wikidata.org/wiki/Q26540', 'display_name': 'Satellite', 'level': 2, 'score': 0.0}, {'id': 'https://openalex.org/C94375191', 'wikidata': 'https://www.wikidata.org/wiki/Q11205', 'display_name': 'Arithmetic', 'level': 1, 'score': 0.0}, {'id': 'https://openalex.org/C33923547', 'wikidata': 'https://www.wikidata.org/wiki/Q395', 'display_name': 'Mathematics', 'level': 0, 'score': 0.0}, {'id': 'https://openalex.org/C48372109', 'wikidata': 'https://www.wikidata.org/wiki/Q3913', 'display_name': 'Binary number', 'level': 2, 'score': 0.0}, {'id': 'https://openalex.org/C17744445', 'wikidata': 'https://www.wikidata.org/wiki/Q36442', 'display_name': 'Political science', 'level': 0, 'score': 0.0}, {'id': 'https://openalex.org/C199539241', 'wikidata': 'https://www.wikidata.org/wiki/Q7748', 'display_name': 'Law', 'level': 1, 'score': 0.0}], 'mesh': [], 'locations_count': 1, 'locations': [{'is_oa': True, 'landing_page_url': 'https://doi.org/10.1086/321552', 'pdf_url': 'https://iopscience.iop.org/article/10.1086/321552/pdf', 'source': {'id': 'https://openalex.org/S1980519', 'display_name': 'The Astrophysical Journal', 'issn_l': '0004-637X', 'issn': ['0004-637X', '1538-4357'], 'is_oa': True, 'is_in_doaj': True, 'is_core': True, 'host_organization': 'https://openalex.org/P4310320083', 'host_organization_name': 'IOP Publishing', 'host_organization_lineage': ['https://openalex.org/P4310311669', 'https://openalex.org/P4310320083'], 'host_organization_lineage_names': ['Institute of Physics', 'IOP Publishing'], 'type': 'journal'}, 'license': None, 'license_id': None, 'version': 'publishedVersion', 'is_accepted': True, 'is_published': True}], 'best_oa_location': {'is_oa': True, 'landing_page_url': 'https://doi.org/10.1086/321552', 'pdf_url': 'https://iopscience.iop.org/article/10.1086/321552/pdf', 'source': {'id': 'https://openalex.org/S1980519', 'display_name': 'The Astrophysical Journal', 'issn_l': '0004-637X', 'issn': ['0004-637X', '1538-4357'], 'is_oa': True, 'is_in_doaj': True, 'is_core': True, 'host_organization': 'https://openalex.org/P4310320083', 'host_organization_name': 'IOP Publishing', 'host_organization_lineage': ['https://openalex.org/P4310311669', 'https://openalex.org/P4310320083'], 'host_organization_lineage_names': ['Institute of Physics', 'IOP Publishing'], 'type': 'journal'}, 'license': None, 'license_id': None, 'version': 'publishedVersion', 'is_accepted': True, 'is_published': True}, 'sustainable_development_goals': [], 'grants': [], 'datasets': [], 'versions': [], 'referenced_works_count': 20, 'referenced_works': ['https://openalex.org/W1966564316', 'https://openalex.org/W1985461863', 'https://openalex.org/W1985511242', 'https://openalex.org/W1985601475', 'https://openalex.org/W1989676900', 'https://openalex.org/W2004511524', 'https://openalex.org/W2023690949', 'https://openalex.org/W2042822028', 'https://openalex.org/W2045557221', 'https://openalex.org/W2056077503', 'https://openalex.org/W2079581806', 'https://openalex.org/W2080769070', 'https://openalex.org/W2101024055', 'https://openalex.org/W2109792165', 'https://openalex.org/W2129743734', 'https://openalex.org/W2150395837', 'https://openalex.org/W2155028161', 'https://openalex.org/W3048052109', 'https://openalex.org/W3099852627', 'https://openalex.org/W343244306'], 'related_works': ['https://openalex.org/W3101533676', 'https://openalex.org/W2372208077', 'https://openalex.org/W2115423126', 'https://openalex.org/W2079817321', 'https://openalex.org/W2045905908', 'https://openalex.org/W2018145098', 'https://openalex.org/W2009077863', 'https://openalex.org/W2000817388', 'https://openalex.org/W1996405199', 'https://openalex.org/W1044062963'], 'abstract_inverted_index': {'Precise': [0], 'Doppler': [1], 'measurements': [2], 'during': [3], '6': [4], 'yr': [5], 'from': [6], 'the': [7, 67, 84, 87, 104, 122, 129, 137, 151, 155], 'Lick': [8], 'and': [9, 31, 40, 49, 52, 58, 81, 150, 166, 178], 'Keck': [10], 'observatories': [11], 'reveal': [12], 'two': [13], 'planets': [14, 76, 159], 'orbiting': [15], 'GJ': [16], '876': [17], '(M4V).': [18], 'The': [19, 61, 95, 141], 'orbital': [20, 34, 62, 119, 139], 'fit': [21], 'yields': [22], 'companion': [23, 97], 'masses': [24], 'of': [25, 36, 45, 54, 69, 86, 109, 121, 136, 154, 175], 'M': [26], 'sin': [27], 'i': [28], '=': [29, 38, 47, 56], '0.56': [30], '1.89': [32], 'MJ,': [33], 'periods': [35, 63], 'P': [37], '30.1': [39], '61.0': [41], 'days,': [42], 'semimajor': [43], 'axes': [44, 85], 'a': [46, 134, 147], '0.13': [48], '0.21': [50], 'AU,': [51], 'eccentricities': [53], 'e': [55], '0.28': [57], '0.10,': [59], 'respectively.': [60], 'are': [64], 'nearly': [65, 93], 'in': [66, 181], 'ratio': [68, 108], '2': [70, 105], ':': [71, 106], '1,': [72], 'unprecedented': [73], 'among': [74, 79], 'major': [75, 156], 'but': [77], 'common': [78], 'moons': [80], 'asteroids.': [82], 'Moreover,': [83], 'elliptical': [88], 'orbits': [89], 'appear': [90], 'to': [91, 103, 115], 'be': [92, 144], 'aligned.': [94], 'inner': [96], 'was': [98], 'not': [99], 'recognized': [100], 'previously': [101], 'owing': [102], '1': [107], 'periods,': [110], 'which': [111, 169], 'allowed': [112], 'its': [113], 'signature': [114], 'masquerade': [116], 'as': [117], 'added': [118], 'eccentricity': [120], 'outer': [123], 'planet.': [124], 'Dynamical': [125], 'simulations': [126], 'show': [127], 'that': [128], 'system': [130], 'is': [131], 'stable': [132], 'within': [133, 172], 'subset': [135], 'observed': [138], 'parameters.': [140], 'stability': [142], 'may': [143], 'provided': [145], 'by': [146], 'mean-motion': [148], 'resonance': [149], 'apparent': [152], 'alignment': [153], 'axes.': [157], 'These': [158], 'pose': [160], 'unsolved': [161], 'questions': [162], 'about': [163], 'their': [164], 'formation': [165], 'dynamical': [167], 'evolution,': [168], 'brought': [170], 'them': [171, 180], '0.08': [173], 'AU': [174], 'each': [176], 'other': [177], 'locked': [179], 'resonance.': [182]}, 'cited_by_api_url': 'https://api.openalex.org/works?filter=cites:W2024785675', 'counts_by_year': [{'year': 2024, 'cited_by_count': 4}, {'year': 2023, 'cited_by_count': 6}, {'year': 2022, 'cited_by_count': 12}, {'year': 2021, 'cited_by_count': 13}, {'year': 2020, 'cited_by_count': 21}, {'year': 2019, 'cited_by_count': 14}, {'year': 2018, 'cited_by_count': 35}, {'year': 2017, 'cited_by_count': 7}, {'year': 2016, 'cited_by_count': 11}, {'year': 2015, 'cited_by_count': 9}, {'year': 2014, 'cited_by_count': 12}, {'year': 2013, 'cited_by_count': 17}, {'year': 2012, 'cited_by_count': 13}], 'updated_date': '2024-12-08T17:44:41.314721', 'created_date': '2016-06-24'}