{"id":"https://openalex.org/A5073784409","orcid":null,"observed_orcids":[],"display_name":"D. Hammer","raw_author_names":["D. Hammer","D. M. Hammer"],"full_name":"Hammer, Derek","works_count":95,"cited_by_count":247,"summary_stats":{"2yr_mean_citedness":0.0,"h_index":2,"i10_index":1},"ids":{"openalex":"https://openalex.org/A5073784409","orcid":null,"observed_orcids":[]},"affiliations":[{"institution":{"id":"https://openalex.org/I1306266525","ror":"https://ror.org/0171mag52","display_name":"Goddard Space Flight Center","country_code":"US","type":"facility","lineage":["https://openalex.org/I1306266525","https://openalex.org/I4210124779"]},"years":[2002]}],"last_known_institutions":null,"topics":[{"id":"https://openalex.org/T10325","display_name":"Astro and Planetary Science","count":91,"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/T11701","display_name":"Space Satellite Systems and Control","count":84,"subfield":{"id":"https://openalex.org/subfields/2202","display_name":"Aerospace Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T12836","display_name":"History and Developments in Astronomy","count":64,"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/T10039","display_name":"Stellar, planetary, and galactic studies","count":27,"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/T10251","display_name":"Solar and Space Plasma Dynamics","count":6,"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"}}],"topic_share":[{"id":"https://openalex.org/T11701","display_name":"Space Satellite Systems and Control","value":0.0004395,"subfield":{"id":"https://openalex.org/subfields/2202","display_name":"Aerospace Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T12836","display_name":"History and Developments in Astronomy","value":0.0001642,"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","value":0.0001537,"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/T10039","display_name":"Stellar, planetary, and galactic studies","value":2.55e-05,"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/T10406","display_name":"Planetary Science and Exploration","value":1.19e-05,"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"}}],"x_concepts":[{"id":"121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","score":0.9087874889373779},{"id":"94081185","wikidata":"https://www.wikidata.org/wiki/Q3559","display_name":"Comet","score":0.8560411930084229},{"id":"87355193","wikidata":"https://www.wikidata.org/wiki/Q411","display_name":"Astrobiology","score":0.6195301413536072},{"id":"127313418","wikidata":"https://www.wikidata.org/wiki/Q1069","display_name":"Geology","score":0.424551784992218},{"id":"41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","score":0.395038902759552}],"counts_by_year":[{"year":1997,"works_count":1,"oa_works_count":0,"cited_by_count":0},{"year":1998,"works_count":2,"oa_works_count":0,"cited_by_count":0},{"year":1999,"works_count":2,"oa_works_count":0,"cited_by_count":0},{"year":2000,"works_count":14,"oa_works_count":0,"cited_by_count":0},{"year":2001,"works_count":19,"oa_works_count":0,"cited_by_count":0},{"year":2002,"works_count":37,"oa_works_count":1,"cited_by_count":244},{"year":2003,"works_count":14,"oa_works_count":0,"cited_by_count":0},{"year":2004,"works_count":2,"oa_works_count":0,"cited_by_count":1},{"year":2005,"works_count":2,"oa_works_count":0,"cited_by_count":2},{"year":2013,"works_count":2,"oa_works_count":0,"cited_by_count":0}],"display_name_alternatives":["D. Hammer","D. M. Hammer"],"block_key":"d hammer","works_api_url":"https://api.openalex.org/works?filter=author.id:A5073784409","updated_date":"2026-10-10T12:59:14","created_date":"2020-09-01T00:00:00"}