Exocomets in the β Pictoris system
(2024) ASTK03 20232Astrophysics
Department of Physics
- Abstract
- Comets have been a source of fascination throughout the history of man. In recent years, advances in technology have opened up for the study of extrasolar objects, among them exocomets. The first exocomets were observed in the β Pictoris system almost 50 years ago and the system has been of interest ever since. Still, it is not clearly known where these bodies originate from and how they end up in their star-grazing orbits. In this work, we attempt to answer these questions through N-body simulations of the system. Firstly, the β Pictoris system was simulated with 20 thousand test particles, their position and orbital elements were tracked over an integration length of 20 million years corresponding to the age of the β Pictoris system.... (More)
- Comets have been a source of fascination throughout the history of man. In recent years, advances in technology have opened up for the study of extrasolar objects, among them exocomets. The first exocomets were observed in the β Pictoris system almost 50 years ago and the system has been of interest ever since. Still, it is not clearly known where these bodies originate from and how they end up in their star-grazing orbits. In this work, we attempt to answer these questions through N-body simulations of the system. Firstly, the β Pictoris system was simulated with 20 thousand test particles, their position and orbital elements were tracked over an integration length of 20 million years corresponding to the age of the β Pictoris system. Test particles were tracked and many were found to collide, be ejected, or become star-grazing. The results show that there are two regions where possible planetesimal reservoirs could be sustained over the age of the system. It was seen that star-grazers form from the two stable regions at the time scale of the age of the system, which could be an explanation to where exocomets in β Pictoris come from. The majority of star-grazers were found to approach the star at highly eccentric or hyperbolic orbits. Secondly, the identified star-grazers were subjected to simulations including the non-gravitational outgassing force, similar to the one experienced by comets in our own solar system. The simulations show that the outgassing force circularizes the eccentric orbits of test particles. Finally, the mass loss rate was estimated for particles exposed to the non-gravitational force. Kilometer sized exocomets that plunge in from the outer solar system can evaporate on a timescale of a few days as they approach the star within a distance of 0.3 AU. (Less)
- Popular Abstract (Swedish)
- Kometer har alltid fascinerat människan då de till skillnad från stjärnor och andra objekt på natthimlen rör sig över den. De består av is som frigör gas när kometen kommer tillräckligt nära solen. Gasen ser ut som en svans och ger kometen dess karakteristiska utseende. Förr i tiden saknade människan kunskap om dessa kroppar och de väckte rädsla. Kometer sågs som dåliga omen och tecken på gudarnas ilska. Under 1500-talet började kometer studeras av astronomer. Trots att förståelsen av kometer ökade, avtog inte fascinationen av dem bland såväl allmänhet som forskare, utan håller kvar sig än idag. Kometer tros bära med sig viktig information om begynnelsen av vårt solsystem, som exempelvis ledtrådar om hur livet på jorden kom till.
Detta... (More) - Kometer har alltid fascinerat människan då de till skillnad från stjärnor och andra objekt på natthimlen rör sig över den. De består av is som frigör gas när kometen kommer tillräckligt nära solen. Gasen ser ut som en svans och ger kometen dess karakteristiska utseende. Förr i tiden saknade människan kunskap om dessa kroppar och de väckte rädsla. Kometer sågs som dåliga omen och tecken på gudarnas ilska. Under 1500-talet började kometer studeras av astronomer. Trots att förståelsen av kometer ökade, avtog inte fascinationen av dem bland såväl allmänhet som forskare, utan håller kvar sig än idag. Kometer tros bära med sig viktig information om begynnelsen av vårt solsystem, som exempelvis ledtrådar om hur livet på jorden kom till.
Detta arbete fokuserar på att undersöka kometer i ett annat solsystem, så kallade exokometer. De är svårare att observera på grund av att de befinner sig väldigt långt bort från jorden. Dock är det både viktigt och relevant att studera exokometer, då de kan hjälpa oss förstå hur andra solsystem formas och därigenom bidra till en bättre förståelse av vårt egna solsystem. Systemet som studeras här heter Beta Pictoris och är det första där exokometer kunnat observeras. Det består av en stjärna, två planeter samt en disk av damm som omger hela systemet. Vi hoppas ta reda på var exokometer som observerats i systemet kommer från och hur de hamnar i extrema omloppsbanor runt sin stjärna.
Vi använder oss av simulationer där vi skapar en modell av Beta Pictoris systemet. Genom simulationerna beräknas gravitationskraften mellan stjärnan och planeterna, så att systemets utveckling genom tid kan studeras. Dessutom inkluderas masslösa test-partiklar i simulationerna och deras rörelse i systemet studerades. Genom detta kan vi se vilka test-partiklar som faller in i stjärnan och blir exokometer. På så sätt hoppas vi kunna dra slutsatser om var exokometerna i systemet kommer från. Förutom detta vill vi se om den kraft som uppstår när exokometen utsöndrar gas har en påverkan på formen av dennes omloppsbana. Vårt syfte är att se ifall kraften kan förklara de extrema omloppsbanorna som exokometerna observeras i. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9147482
- author
- Jaworska, Klaudia LU
- supervisor
- organization
- course
- ASTK03 20232
- year
- 2024
- type
- M2 - Bachelor Degree
- subject
- report number
- 2024–EXA218
- language
- English
- id
- 9147482
- date added to LUP
- 2024-01-31 15:51:20
- date last changed
- 2024-01-31 15:51:20
@misc{9147482,
abstract = {{Comets have been a source of fascination throughout the history of man. In recent years, advances in technology have opened up for the study of extrasolar objects, among them exocomets. The first exocomets were observed in the β Pictoris system almost 50 years ago and the system has been of interest ever since. Still, it is not clearly known where these bodies originate from and how they end up in their star-grazing orbits. In this work, we attempt to answer these questions through N-body simulations of the system. Firstly, the β Pictoris system was simulated with 20 thousand test particles, their position and orbital elements were tracked over an integration length of 20 million years corresponding to the age of the β Pictoris system. Test particles were tracked and many were found to collide, be ejected, or become star-grazing. The results show that there are two regions where possible planetesimal reservoirs could be sustained over the age of the system. It was seen that star-grazers form from the two stable regions at the time scale of the age of the system, which could be an explanation to where exocomets in β Pictoris come from. The majority of star-grazers were found to approach the star at highly eccentric or hyperbolic orbits. Secondly, the identified star-grazers were subjected to simulations including the non-gravitational outgassing force, similar to the one experienced by comets in our own solar system. The simulations show that the outgassing force circularizes the eccentric orbits of test particles. Finally, the mass loss rate was estimated for particles exposed to the non-gravitational force. Kilometer sized exocomets that plunge in from the outer solar system can evaporate on a timescale of a few days as they approach the star within a distance of 0.3 AU.}},
author = {{Jaworska, Klaudia}},
language = {{eng}},
note = {{Student Paper}},
title = {{Exocomets in the β Pictoris system}},
year = {{2024}},
}