From Instituto de Astrofísica de Andalucía, IAA-CSIC via Manu Garcia of IAC: “The complex dynamics of the ring systems miniature solar system”

From Instituto de Astrofísica de Andalucía, IAA-CSIC

11/21/18
Manu Garcia

From Manu Garcia, a friend from IAC.

The universe around us.
Astronomy, everything you wanted to know about our local universe and never dared to ask.

Ring systems around small celestial bodies.

Result of a numerical integration showing the development of seven hundred particles orbiting an elongated body size and shape similar to Chariclo (an ellipsoid with the major axes of 314 x 278 x 172 kilometers). The particles are subject to a radial dissipative force that simulates the effect of collisions. After three months (upper panel), most of the particles within the corotación (190 kilometers from the center of Chariclo) fell on the body. After a year (central panel), it has been emptied the internal area, and after a year (lower panel) particles continue their migration to the outer areas.

The discovery of rings around the Solar System bodies that are not planets, like the dwarf planet Haumea or centaur Chariclo, showed that it is most common structures than previously thought. Work in the Institute of Astrophysics of Andalusia (IAA-CSIC) participates, analyzes the complex dynamics of these rings in miniature.

Until five years ago it was thought that the rings were unique features of large gaseous planets, like Saturn or Uranus, but the discovery of rings around no planetary bodies in the solar system forced to review these structures, apparently more common than is I thought. Now, a job in which the Institute of Astrophysics of Andalusia (IAA-CSIC) participates has analyzed the dynamics of these ring systems in miniature, more complex in some cases than the giant planets because of the terrain or elongated shape of these bodies.

In 2013 and 2017, respectively, two bodies of the solar system entered the small group of objects ring: Chariclo, the largest of a population of objects known as centaur, which are among Jupiter and Neptune and share features with both comets as asteroids; and Haumea, a dwarf planet beyond Neptune with ellipsoidal shape and size, most side, similar to Pluto.

The complex dynamics of the ring systems miniature solar system. Image author transneptunian object Haumea.

Both have narrow and confined rings, suggesting the existence of “satellites shepherds” that contribute to the rings remain confined as those seen around Saturn and Uranus. However, there is an important difference between giant planets and no planetary bodies, since the latter can show very irregular shapes: may have reliefs such as craters or mountains, nonexistent in the gaseous planets, or show an elongated shape (Haumea, for example, it has a flattened shape as a rugby ball).

“In this study we showed that these deformations or irregularities create gravitational resonances between the body and the ring particles that cause synchronous orbit (or corotation), wherein the particles have an orbital period equal to the rotation of the central body, is empty: the particles of the disc that are within the corotation fall toward the central object and, conversely, that are outside are pushed outward beyond the 1: 2 resonance (in which complete a revolution around the body at the time this tour twice on itself), “said Pablo Santos-Sanz, researcher at the Institute of Astrophysics of Andalusia (IAA-CSIC), which participates in the work.

The time scales associated with the migration of the particles of the disk are small, a few years in the case of elongated bodies, as Haumea. For a spherical body with an equatorial mountain five kilometers, the area co-rotation can be emptied in less than a million years, a period of very short time compared to the age of the Solar System.

These findings are confirmed in the known objects: rings Chariclo and Haumea are four hundred and two thousand two hundred and ninety kilometers outside its resonances 1: 2, which occur three hundred and fifty kilometers respectively seven hundred thou.

Another prediction paper presented affects the rotation of the body, to be rotated very quickly on itself so that the particles at that distance are kept forming a stable ring or, otherwise, would vent further, to finish perhaps forming satellites . For frozen bodies as Chariclo and Haumea rotation period must be less than seven hours, which is also true, and rotating on themselves seven and four hours, respectively.

“This is a field still new study because five years ago we did not know that these objects could present rings. These mechanisms could also explain the formation of satellites around certain bodies through the migration of a disk initially more next to the object, “says Pablo Santos-Sanz (IAA-CSIC).

Science paper:
Ring around non-axisymmetric dynamics with application to Chariklo bodies and Haumea
Nature Astronomy

See the full article here.

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Welcome to the Instituto de Astrofísica de Andalucía (IAA). The IAA is an institute of Consejo Superior de Investigaciones Científicas (CSIC) in Granada – Andalucía. The activities of the IAA (CSIC) are related to research in the field of Astrophysics and the development of instruments for telescopes and space vehicles.

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Introduction

The IAA has as its general scientific objective to help increase the bulk of knowledge about our universe, from the closest at hand, our solar system, to an overall scale of the entire universe, improving descriptions and analysing the physical processes that take place there. The nature of this aim demands a multi-disciplinary approach, requiring a combination of theory, observation and technology in different areas of physics and engineering. Although the IAA is a centre for pursuing basic science, we are aware of the role that astrophysics plays as a user and producer of new technologies.

To achieve our overarching objective, different scientific programmes are being undertaken with specific aims and timetables, encompassing four large areas of astrophysics: the solar system; star formation, structure and evolution; galaxy structure and evolution; and cosmology. Basic science has been and continues to be the motor for training scientific and technical staff, as well as for stimulating the development of other disciplines. The history of the IAA clearly depicts the observational function of the centre.

The telescopes installed in the Observatorio de Sierra Nevada (OSN), reflect a scientific policy with the clear objective of ensuring continued access to observational means to undertake far-reaching scientific projects. This fact adds singularity to the centre and at the same time offers the challenge and incentive for research at the IAA. The design and construction of instruments for the OSN, as well as others to be carried in special space vehicles, not only serve as support for basic research by the different teams of the IAA, but also represent activity of prime importance for the appropriate combination of research and development.

The Institute of Astrophysics of Andalusia (Spanish: Instituto de Astrofísica de Andalucía, IAA-CSIC) is a research institute funded by the High Council of Scientific Research of the Spanish government Consejo Superior de Investigaciones Científicas (CSIC), and is located in Granada, Andalusia, Spain. IAA activities are related to research in the field of astrophysics, and instrument development both for ground-based telescopes and for space missions. Scientific research at the Institute covers the solar system, star formation, stellar structure and evolution, galaxy formation and evolution and cosmology. The IAA was created as a CSIC research institute in July 1975. Presently, the IAA operates the Sierra Nevada Observatory, and (jointly with the also the Max-Planck Institute of Heidelberg) the Calar Alto Observatory.