legacy page  
     homeaboutessential guidepicture of the daythunderblogsnewsmultimediapredictionsproductsget involvedcontact

picture of the day

chronological archive               subject archive


The rings and moons of Uranus. Credit: NASA, ESA, and A. Field of STScI.


Son of Gaea
Aug 25, 2010

One of the largest planets in the Solar System is also one of the most enigmatic.

Uranus is the coldest planet in the Solar System at -224° Celsius. The refrigerated dwarf Pluto is colder, but by consensus it has been relegated to the planetesimal category and no longer qualifies as a fully fledged planet.

No one knows why Uranus is so cold—colder than its more remote neighbor Neptune at -214° Celsius. Neptune lies at a mean distance from the Sun of 4,504,300,000 kilometers and Uranus at 2,870,990,000 kilometers, so it receives four times less solar radiation. However, astronomers think that the low temperature anomaly on Uranus could be due to its rotational vector.

Uranus is tipped on its side by 97° past vertical, prompting scientists to speculate that the gas giant was involved in a massive collision sometime in its early history. It is also thought that colliding with that other large object might have released much of its heat, although the precise mechanism for how a collision can cool down a planet remains a mystery.

Uranus does not radiate a great deal of energy in the infrared wavelengths, so its interior is much colder than that of Jupiter, for instance. Based on observations by the Keck telescope, Jupiter's infrared signature corresponds to an internal temperature of approximately 29727° Celsius, whereas the internal temperature of Uranus is about 4727° Celsius. If the Sun were to disappear tomorrow, Jupiter would still be visible as a faint, reddish glow, but Uranus would be almost invisible against the black background of space.

Like its other gas giant siblings, Uranus has a complex system of rings in orbit with a bevy of satellites. Currently, there are 27 known moons circling the planet, ranging in size from Miranda (470 kilometers in diameter) to Titania (1578 kilometers in diameter). The most unusual thing about the rings and moons is their placement.

Uranus is revolving around the Sun while lying on its side, and its moons and rings are also orbiting along with it in the same orientation. Instead of circling the planet near the plane of the ecliptic, they are inclined from the vertical by 97°, perpendicular to the rest of the Solar System. However, there are several small moons that orbit in the "correct" angle of inclination, crossing from axial pole to axial pole, as well as moving in a retrograde fashion. Why this is so is not known, although it has been suggested that these moons were "captured" by Uranus and did not evolve with it out of a hypothetical nebular cloud.

The rings of Uranus are similar to those around Saturn and Jupiter. Neptune possesses a system of rings as well, but they are thin and only partial, appearing more like ring segments or arcs than a complete set of bracelets. There are at least 13 rings around Uranus, with the potential for more as the refurbished Hubble Space Telescope turns its new eyes on the planet.

The magnetic field generated by Uranus is probably the most unusual aspect of a planet whose structure is dominated by eccentricities. Unlike Saturn, whose magnetic poles are aligned almost exactly with its axial poles, or Jupiter, whose field is offset from vertical by a mere 10°, the magnetic poles of Uranus are offset at a slant from its rotational axis by 60°. Neptune exhibits a similar field offset, with the majority of the field strength concentrated in one hemisphere—like Uranus.

Why Jupiter and Saturn have intense magnetic fields, while Uranus and Neptune have weak fields is not understood by conventional astronomers or by Electric Universe theorists. In the Electric Universe model, however, there is no dependence on internal composition, such as an iron core acting as a dynamo, or a compressed core of metallic hydrogen creating the field through rapid rotation. What is most likely occurring is that the rapid rotation of charged particles in the plasma making up the giant planets is creating a powerful surge of electromagnetic energy. It is common knowledge that a rotating electrically charged body will produce a magnetic field.

All four gas giant planets spin at enormous velocities for their sizes. Uranus is 51120 kilometers in diameter, yet it completes one rotation in just under 18 hours. Recently, a current sheet was found connecting Uranus with its moon Miranda, feeding current into the auroral field, proving that there is an electric circuit within the Uranian system. In fact, the magnetosphere of Uranus extends out beyond its farthest moon and is wide enough to encompass its entire ring system.

It is to be hoped that outlining the problems and anomalies associated with one of the coldest of the cold places in existence will motivate more interest and more investigation. We have made little attempt to explain what is found on Uranus because explanations have yet to be forthcoming—electrical conditions usually require in situ measurements. So far, only one space probe has visited Uranus, and the Earth-based telescopes on the ground and in orbit have just recently been upgraded to the point where sharper images can be synthesized. We can only wait for more data.

Stephen Smith



"The Cosmic Thunderbolt"

YouTube video, first glimpses of Episode Two in the "Symbols of an Alien Sky" series.


And don't forget: "The Universe Electric"

Three ebooks in the Universe Electric series are now available. Consistently praised for easily understandable text and exquisite graphics.

  This free site search script provided by JavaScript Kit  
  FREE update -

Weekly digest of Picture of the Day, Thunderblog, Forum, Multimedia and more.
*** NEW DVD ***
  Symbols of an Alien Sky
Selections Playlist

An e-book series
for teachers, general readers and specialists alike.
(FREE viewing)
  Thunderbolts of the Gods

  Follow the stunning success of the Electric Universe in predicting the 'surprises' of the space age.  
  Our multimedia page explores many diverse topics, including a few not covered by the Thunderbolts Project.  

Authors David Talbott and Wallace Thornhill introduce the reader to an age of planetary instability and earthshaking electrical events in ancient times. If their hypothesis is correct, it could not fail to alter many paths of scientific investigation.
More info
Professor of engineering Donald Scott systematically unravels the myths of the "Big Bang" cosmology, and he does so without resorting to black holes, dark matter, dark energy, neutron stars, magnetic "reconnection", or any other fictions needed to prop up a failed theory.
More info
In language designed for scientists and non-scientists alike, authors Wallace Thornhill and David Talbott show that even the greatest surprises of the space age are predictable patterns in an electric universe.
More info

The opinions expressed in the Thunderbolts Picture Of the Day are those of the authors of
the material, and do not necessarily reflect the views of the Thunderbolts Project.
The linking to material off-site in no way endorses such material and the Thunderbolts
Project has no control of nor takes any responsibility for any content on linked sites.

EXECUTIVE EDITORS: David Talbott, Wallace Thornhill
CONTRIBUTING EDITORS: Michael Armstrong, Dwardu Cardona,
Ev Cochrane, C.J. Ransom, Don Scott,
Rens van der Sluijs, Ian Tresman,
Tom Wilson
WEBMASTER: Brian Talbott
© Copyright 2010:
top ]

home   •   picture of the day   •   thunderblogs   •   multimedia   •   resources   •   forum   •   updates   •   contact us   •   support us