Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New moon making waves


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:

More articles from Physics and Astronomy:

nachricht Physicists made crystal lattice from polaritons
20.03.2018 | ITMO University

nachricht Mars' oceans formed early, possibly aided by massive volcanic eruptions
20.03.2018 | University of California - Berkeley

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: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

Physicists made crystal lattice from polaritons

20.03.2018 | Physics and Astronomy

Mars' oceans formed early, possibly aided by massive volcanic eruptions

20.03.2018 | Physics and Astronomy

Thawing permafrost produces more methane than expected

20.03.2018 | Earth Sciences

Science & Research
Overview of more VideoLinks >>>