Related papers: Unprecedented Daylight Display of Kreutz Sungrazer…
We present the results of our orbital computations in support of the recently proposed contact-binary model for the Kreutz sungrazer system (Sekanina 2021, 2022). We demonstrate that comet Ikeya-Seki (C/1965 S1) previously passed perihelion…
Extending the investigation of the presumed primordial comet as part of continuing work on a new model of the Kreutz sungrazer system, I confront a previously derived set of orbital elements with Aristotle's remarks in his Meteorologica to…
This paper describes progress achieved in early investigations of the orbital motion and light curve of comet C/2026 A1 (MAPS), the third ground-based discovery of a Kreutz sungrazer in the 21st century. The highly unusual trait of the…
I summarize and streamline the results of recent modeling of the orbital evolution and cascading fragmentation of the Kreutz sungrazers. The model starts with Aristotle's comet -- the progenitor whose nucleus is assumed to be a contact…
New insights into the history of C/1843 D1 and C/1882 R1, the two celebrated Kreutz sungrazers, are provided by assessing evidence on their appearance at the previous perihelion return, known as X/1106 C1 and the Chinese comet of 1138 (Ho's…
Until the second half of the 19th century, two or more brief appearances of bright comets, such as the ones in 1668 and 1702, alike in aspect and motion, seen with a tail near the Sun, were almost universally believed to be periodic returns…
A vast majority of bright comets between the late 2nd century and the early 18th century, moving in potentially Kreutz orbits according to Hasegawa & Nakano (2001), was first sighted between 2 and 16 days after perihelion, thanks to the…
In the context of a recently proposed contact-binary model of the Kreutz system, all its members are products of the process of cascading fragmentation of the two lobes of the parent, Aristotle's comet of 372 BC. This process presumably…
Tidal fragmentation at perihelion and nontidal fragmentation elsewhere cause the orbital distribution of Kreutz sungrazers of all sizes to be extremely complicated and highly nonuniform. Among the features are (largely fortuitous) clusters…
Most Kreutz family sungrazing comets are discovered only days before perihelion, severely limiting observational opportunities to study their physical nature and decay. Kreutz sungrazer C/2024 S1 (ATLAS) was discovered a month before…
The structure of the Kreutz system of sungrazing comets is shown to be much more complex than formerly believed. Marsden's (1989) division into three subgroups (I, II, IIa) is now greatly expanded, as new evidence is being offered on nine…
We present the history of investigation of the dynamical properties of pairs and groups of genetically related long-period comets (other than the Kreutz sungrazing system). Members of a comet pair or group move in nearly identical orbits…
Data on perihelion fragmentation of the Great September Comet of 1882 (C/1882 R1), a prominent member of the Kreutz sungrazer system, are employed to estimate the size of the nucleus along the radius vector at the time of splitting. The…
Comet ATLAS (C/2024 S1) is a bright dwarf sungrazer, the second Kreutz comet discovery from the ground this century, 13 years after comet Lovejoy (C/2011 W3). The Population II membership of comet ATLAS sets it apart from the overwhelming…
The goal of this investigation is to reinterpret and upgrade the astrometric and other data on comet C/1945 X1, the least prominent among the Kreutz system sungrazers discovered from the ground in the 20th century. The central issue is to…
I investigate the nature of the transient nebulous companions to the sungrazing comet C/1882 R1, known as the Great September Comet. The features were located several degrees to the southwest of the comet's head and reported independently…
I present the results of the first comprehensive effort aimed at modeling a major component of the stream of SOHO sungrazers, 5000 of which have been detected by the onboard coronagraphs since 1996. The stream of Population I of the Kreutz…
We investigate the relationships among the angular orbital elements --- the longitude of the ascending node, Omega, the inclination, i, and the argument of perihelion, omega --- of the Kreutz system's faint, dwarf sungrazers observed only…
We examine properties of the population of SOHO/STEREO (dwarf) Kreutz sungrazing comets from 2004 to 2013, including the arrival rates, peculiar gaps, and a potential relationship to the spectacular comet C/2011 W3 (Lovejoy). Selection…
Comet C/2025 K1 (ATLAS) reached perihelion at 0.33 au on 2025 October 8. Daily monitoring by the LCO Outbursting Objects Key Project revealed a major activity increase between November 2 and 4, accompanied by rapid changes in coma…