Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New moon making waves

12.05.2005


The NASA/ESA/ASI Cassini spacecraft has confirmed earlier suspicions of an unseen moon hidden in a gap in Saturn’s outer A ring. A new image shows the new moon and the waves it raises in the surrounding ring material.


New wave-making moon S/2005 S1 - Credit: NASA/JPL/Space Science Institute



The moon, provisionally named S/2005 S1, was first seen in a time-lapse sequence of images taken on 1 May 2005, as Cassini began its climb to higher inclinations in orbit around Saturn. A day later, an even closer view was obtained, which allowed the moon’s size and brightness to be measured.

The images show the tiny object in the centre of the Keeler gap and the wavy patterns in the gap edges that are generated by the moon’s gravitational influence. The Keeler gap is located about 250 kilometres inside the outer edge of the A ring, which is also the outer edge of the bright main rings.


The new object, or ’moonlet’, is about 7 kilometres across and reflects about half the light falling on it - a brightness that is typical of the particles in the nearby rings. It orbits approximately 136 505 kilometres from the centre of Saturn. More Cassini observations will be needed to determine whether the moon’s orbit around Saturn is circular or ’eccentric’(like an oval).

S/2005 S1 is the second known moon to exist within Saturn’s rings. The other is Pan, 25 kilometres across, which orbits in the Encke gap. Atlas and other moons exist outside the main ring system, as do the two F ring ’shepherd’ moons, Prometheus and Pandora.

Imaging scientists had predicted the new moon’s presence and its orbital distance from Saturn after last July’s sighting of a set of peculiar spiky and wispy features in the Keeler gap’s outer edge. The similarities of the Keeler gap features to those noted in Saturn’s F ring and the Encke gap led imaging scientists to conclude that a small body, a few kilometres across, was lurking in the centre of the Keeler gap, awaiting discovery.

"The obvious effect of this moon on the surrounding ring material will allow us to determine its mass and test our understanding of how rings and moons affect one another," said Dr Carl Murray, imaging team member from Queen Mary College, University of London.

An estimate of the moon’s mass, along with a measure of its size, yields information on its physical composition. For instance, the new moonlet might be porous, like an orbiting icy rubble pile. Other moons near the outer edge of Saturn’s rings such as Atlas, Prometheus and Pandora are also porous. Whether a moon is porous or dense says something about how it was formed and its subsequent collision history.

"Some of the most illuminating dynamical systems we might hope to study with Cassini are those involving moons embedded in gaps," said Dr Carolyn Porco, imaging team leader at the Space Science Institute.

"By examining how such a body interacts with its companion ring material, we can learn something about how the planets in our solar system might have formed out of the nebula of material that surrounded the Sun long ago. We anticipate that many of the gaps in Saturn’s rings have embedded moons, and we’ll be in search of them from here on."

The Cassini-Huygens mission is a co-operative project of NASA, ESA and ASI, the Italian space agency.

Monica Talevi | alfa
Further information:
http://www.esa.int/SPECIALS/Cassini-Huygens/SEM1XQ5TI8E_0.html

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>