The perihelion of long-period comets places them near the Sun so they may exhibit activity.Before 2013 LU28 reached its perihelion,we performed a continuous observation to detect possible activity.Using the Lijiang 2....The perihelion of long-period comets places them near the Sun so they may exhibit activity.Before 2013 LU28 reached its perihelion,we performed a continuous observation to detect possible activity.Using the Lijiang 2.4 m telescope with a Johnson R filter,we measured the brightness of 2013 LU28 from 2024 January 3 to April 13.The instrumental magnitudes were subsequently transformed into the Pan-STARRS r system.Due to the noticeable descending trend in the absolute magnitude,we verified the cometary activity and constrained some photometric properties of 2013 LU28.Consequently,the increased cross-sectional area had a rate of 42.8 km^(2)day^(−1),and the corresponding mass-loss rate was 2.64 kg s^(−1)with the assumption of a dust-particle size a=10 mm and the densityρ=400 kg m^(−3).We estimated the nucleus radius as 0.11■r_(n)■0.21 km for CO sublimation and 0.20■r_(n)■0.71 km for CO_(2)sublimation and the grain size of 2013 LU28 was ac;117.95μm for CO and ac■7.57μm for CO_(2).The long-term observations provided in this paper will offer significant value for investigating the mechanisms driving the activity of 2013 LU28.展开更多
基金Funding for the telescope has been provided by CAS and the People’s Government of Yunnan Provincefunded by the Civil Aerospace pre-research project D020302+2 种基金National Natural Science Foundation of China (U12150009,12150009)the CAS Light of West China Programthe science research grants from the China Manned Space Project with NO.CMS-CSST-2021-B10
文摘The perihelion of long-period comets places them near the Sun so they may exhibit activity.Before 2013 LU28 reached its perihelion,we performed a continuous observation to detect possible activity.Using the Lijiang 2.4 m telescope with a Johnson R filter,we measured the brightness of 2013 LU28 from 2024 January 3 to April 13.The instrumental magnitudes were subsequently transformed into the Pan-STARRS r system.Due to the noticeable descending trend in the absolute magnitude,we verified the cometary activity and constrained some photometric properties of 2013 LU28.Consequently,the increased cross-sectional area had a rate of 42.8 km^(2)day^(−1),and the corresponding mass-loss rate was 2.64 kg s^(−1)with the assumption of a dust-particle size a=10 mm and the densityρ=400 kg m^(−3).We estimated the nucleus radius as 0.11■r_(n)■0.21 km for CO sublimation and 0.20■r_(n)■0.71 km for CO_(2)sublimation and the grain size of 2013 LU28 was ac;117.95μm for CO and ac■7.57μm for CO_(2).The long-term observations provided in this paper will offer significant value for investigating the mechanisms driving the activity of 2013 LU28.
