{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/42444"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/42444","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Detecting surface inhomogeneity of asteroids","abstract":"This thesis investigates the detection of surface composition inhomogeneity on asteroids using time-series spectroscopy and photometry. Observations were conducted on three test cases—Pluto, asteroid 2005 EK70, and the weather satellite Meteosat-11 using the Mookodi instrument on the Lesedi telescope. For Pluto, time-resolved spectroscopy revealed methane ice absorption bands, with band depths varying between 3.33% and 4.80%, consistent with previously reported values. Photometric analysis supported these results, showing an r − i colour variation linked to surface inhomogeneity. For asteroid 2005 EK70, no significant spectral variations were detected, suggesting a uniform surface composition. The asteroid's diameter was determined to be 1.25 ± 0.26 km, with a rotation period of 4.34 hours, indicating it is stable. The third test case, Meteosat-11, served as a control to verify Mookodi's ability to track stationary objects. These findings demonstrate the capability of ground-based instruments like Lesedi to detect surface composition inhomogeneity from Earth. Future work could further refine these methods and apply them to a wider range of solar system objects.","abstract_html":"This thesis investigates the detection of surface composition inhomogeneity on asteroids using time-series spectroscopy and photometry. Observations were conducted on three test cases—Pluto, asteroid 2005 EK70, and the weather satellite Meteosat-11 using the Mookodi instrument on the Lesedi telescope. For Pluto, time-resolved spectroscopy revealed methane ice absorption bands, with band depths varying between 3.33% and 4.80%, consistent with previously reported values. Photometric analysis supported these results, showing an r − i colour variation linked to surface inhomogeneity. For asteroid 2005 EK70, no significant spectral variations were detected, suggesting a uniform surface composition. The asteroid's diameter was determined to be 1.25 ± 0.26 km, with a rotation period of 4.34 hours, indicating it is stable. The third test case, Meteosat-11, served as a control to verify Mookodi's ability to track stationary objects. These findings demonstrate the capability of ground-based instruments like Lesedi to detect surface composition inhomogeneity from Earth. Future work could further refine these methods and apply them to a wider range of solar system objects.","abstract_has_math":false,"creators":["Mnisi, Mandlenkosi"],"institution":"Department of Astronomy","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Erasmus, Nicolas","Monageng, Itumeleng"],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025","date_published":"2025","updated_at":"2026-07-22T22:23:31Z","subjects":["astronomy"],"languages":["en"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/42444","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Erasmus, Nicolas","Monageng, Itumeleng"]},{"key":"dc:creator","label":"Author","values":["Mnisi, Mandlenkosi"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2025-12-17T12:41:04Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2025-12-17T12:41:04Z"]},{"key":"dc:date.issued","label":"Date","values":["2025"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Astronomy"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Thesis / Dissertation"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Masters","MSc"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["astronomy"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/42444"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["This thesis investigates the detection of surface composition inhomogeneity on asteroids using time-series spectroscopy and photometry. Observations were conducted on three test cases—Pluto, asteroid 2005 EK70, and the weather satellite Meteosat-11 using the Mookodi instrument on the Lesedi telescope. For Pluto, time-resolved spectroscopy revealed methane ice absorption bands, with band depths varying between 3.33% and 4.80%, consistent with previously reported values. Photometric analysis supported these results, showing an r − i colour variation linked to surface inhomogeneity. For asteroid 2005 EK70, no significant spectral variations were detected, suggesting a uniform surface composition. The asteroid's diameter was determined to be 1.25 ± 0.26 km, with a rotation period of 4.34 hours, indicating it is stable. The third test case, Meteosat-11, served as a control to verify Mookodi's ability to track stationary objects. These findings demonstrate the capability of ground-based instruments like Lesedi to detect surface composition inhomogeneity from Earth. Future work could further refine these methods and apply them to a wider range of solar system objects."]},{"key":"dc:title","label":"Title","values":["Detecting surface inhomogeneity of asteroids"]}]}],"canonical_facts":{"dc:contributor.advisor":["Erasmus, Nicolas","Monageng, Itumeleng"],"dc:creator":["Mnisi, Mandlenkosi"],"dc:date.accessioned":["2025-12-17T12:41:04Z"],"dc:date.available":["2025-12-17T12:41:04Z"],"dc:date.issued":["2025"],"dc:description.abstract":["This thesis investigates the detection of surface composition inhomogeneity on asteroids using time-series spectroscopy and photometry. Observations were conducted on three test cases—Pluto, asteroid 2005 EK70, and the weather satellite Meteosat-11 using the Mookodi instrument on the Lesedi telescope. For Pluto, time-resolved spectroscopy revealed methane ice absorption bands, with band depths varying between 3.33% and 4.80%, consistent with previously reported values. Photometric analysis supported these results, showing an r − i colour variation linked to surface inhomogeneity. For asteroid 2005 EK70, no significant spectral variations were detected, suggesting a uniform surface composition. The asteroid's diameter was determined to be 1.25 ± 0.26 km, with a rotation period of 4.34 hours, indicating it is stable. The third test case, Meteosat-11, served as a control to verify Mookodi's ability to track stationary objects. These findings demonstrate the capability of ground-based instruments like Lesedi to detect surface composition inhomogeneity from Earth. Future work could further refine these methods and apply them to a wider range of solar system objects."],"dc:identifier.uri":["http://hdl.handle.net/11427/42444"],"dc:language.iso":["en"],"dc:publisher.department":["Department of Astronomy"],"dc:publisher.institution":["University of Cape Town"],"dc:subject":["astronomy"],"dc:title":["Detecting surface inhomogeneity of asteroids"],"dc:type":["Thesis / Dissertation"],"dc:type.qualificationlevel":["Masters","MSc"]},"updated_at":"2026-07-22T22:23:31Z"}