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Using a new process in planetary formation modeling, where planets grow from tiny bodies called "pebbles," Southwest Research Institute scientists can explain why Mars is so much smaller than Earth. This same process also explains the rapid formation of the gas giants Jupiter and Saturn, as reported earlier this year. "This numerical simulation actually reproduces the structure of the inner solar system, with Earth, Venus, and a smaller Mars," said Hal Levison, an Institute scientist at the SwRI Planetary Science Directorate. He is the first author of a new paper published in the Proceedings of the National Academy of Sciences...

NASA’s New Horizons spacecraft has sent incredible images of Pluto’s largest moon Charon back to Earth. The latest images reveal the moon’s complex and violent history, according to NASA. “Many New Horizons scientists expected Charon to be a monotonous, crater-battered world; instead, they’re finding a landscape covered with mountains, canyons, landslides, surface-color variations and more,” explained the space agency, in a statement. The high-resolution images, which were taken on July 14 and transmitted to Earth on Sept. 21, reveal a belt of fractures and canyons just north of the moon’s equator. Four times as long as the Grand Canyon, and...

The paper ... noted that a number of large, very remote objects share a similar orbital angle. That's suspicious if you're an astronomer expecting to see a random distribution of objects. The key orbital feature is known, rather obtusely, as the “argument of perihelion.” We're not shy of complicated orbital concepts (we try to toss around the phrase "obliquity of the ecliptic" whenever possible), but this one is not very easy to explain. "The argument of perihelion is the angle at which an object comes to perihelion with respect to the ecliptic plane," Sheppard said in an e-mail. Mike Brown,...

Suddenly, space is getting interesting again. After decades of going boldly nowhere in low Earth orbit, Man, or rather his robotic emissaries, have made some startling discoveries in our Solar System. Cold, distant Pluto is – who would have thought it? – turning out to be one of the most interesting planets (yes, it is a planet) in the Solar System. Before the New Horizons probe turned up earlier this month, astronomers assumed it would be a dull, grey cratered rock. [SNIP] If we find life of any kind out there – whether it be Martian microbes (we have several...

What's the spot on World Ceres? Can you guess what's creating those unusual bright spots on Ceres? On March 6, NASA's Dawn spacecraft began orbiting Ceres, the largest body in the main asteroid belt between Mars and Jupiter. Even before the spacecraft arrived at the dwarf planet, images revealed mysterious bright spots that captivated scientists and observers alike. Until Dawn gets a closer look over the next few months, it's anyone's guess what those spots could be. So, go ahead! Cast your vote below. - See more at: http://www.jpl.nasa.gov/dawn/world_ceres/#sthash.bwDwq56N.dpuf

Humanity has looked up to the "Man in the Moon" for millennia, but this could be one of our first views of the "Person in Pluto." The views are getting better and better as NASA's New Horizons spacecraft approaches Pluto for its July 14 flyby — and the pictures have begun revealing surface details. Ian Regan, an image-processing enthusiast from Plymouth, England, combined four images from New Horizons' Long Range Reconnaissance Imager with color data from the probe's Multispectral Visible Imaging Camera to produce an eerie colorized view of Pluto and its biggest moon, Charon.

This is a waaaaaaaaaaaaay cool scale model of the Solar System that shows just how freakin' HUGE our own "little" neck of the woods really is. Scroll to the right... If the Moon Were Only 1 Pixel

Just saw these cool pics of opposite views of the same thing...sort of:

Larger than the planet Mercury, Ganymede is one of four moons discovered by Galileo in 1610, easily visible in small telescope and large binoculars. The subsurface ocean confirmed by Hubble is believed to be at least 60 miles thick, containing more water than all of Earth's ocean's combined. As such, Ganymede joins a growing list of planets and moons in Earth's solar system, including Jupiter's moon Europa and Saturn's moon Enceladus, that are known to harbor vast reservoirs of liquid water. The latest findings using the Hubble Space Telescope build on earlier observations by NASA's Galileo spacecraft that showed Ganymede...

Explanation: On another Valentine's Day 25 years ago, cruising four billion miles from the Sun, the Voyager 1 spacecraft looked back one last time to make this first ever Solar System family portrait. The complete portrait is a 60 frame mosaic made from a vantage point 32 degrees above the ecliptic plane. In it, Voyager's wide angle camera frames sweep through the inner Solar System at the left, linking up with gas giant Neptune, the Solar System's outermost planet, at the far right. Positions for Venus, Earth, Jupiter, Saturn, Uranus, and Neptune are indicated by letters, while the Sun is...

Paris (AFP) - The Solar System has at least two more planets waiting to be discovered beyond the orbit of Pluto, Spanish and British astronomers say. The official list of planets in our star system runs to eight, with gas giant Neptune the outermost. Beyond Neptune, Pluto was relegated to the status of "dwarf planet" by the International Astronomical Union in 2006, although it is still championed by some as the most distant planet from the Sun. In a study published in the latest issue of the British journal Monthly Notices of the Royal Astronomical Society, researchers propose that "at...

Presently, our solar system is known to contain 4 fully-fledged rocky worlds: Mercury, Venus, Earth and Mars; 2 ice-giants: Neptune and Uranus; 2 gas-giants, Saturn and Neptune; 5 dwarf-planets, Ceres. Pluto, Eris, MakeMake, Haumea; around 100 moons; and an unknowable number of comets, asteroids and minor planets. Indeed, we’ve only begun to understand the full scope of our local corner of our galaxy, and new information emerges on a monthly-basis, yet there a number of seemingly obvious things that remain unknown. For instance, long before Pluto’s existence was deduced, astronomers scoured the outer solar system in search of another large...

To find out, scientists turned to chemistry. Here on Earth, about one in every 3,000 molecules of water is made with a deuterium atom instead of a hydrogen atom. A deuterium atom is similar to a hydrogen atom except that its nucleus contains a proton and a neutron, instead of a lone proton. (Both atoms also contain a single electron.) That makes deuterium twice as heavy as hydrogen, which is why water molecules made with deuterium atoms (HDO) are known as “heavy water.” At the time that our sun was born, the ratio of deuterium to hydrogen throughout the universe...

3D Solar system Simulator For Fun and Navigational Assistance http://solarsystem.appzend.net/

A strange ribbon of energy and particles at the edge of the solar system first spotted by a NASA spacecraft appears to serve as a sort of "roadmap in the sky" for the interstellar magnetic field, scientists say. By comparing ground-based studies and in-space observations of solar system's mysterious energy ribbon, which was first discovered by NASA's Interstellar Boundary Explorer (IBEX) in 2009, scientists are learning more details about the conditions at the solar system's edge. The study also sheds light into the sun's environment protects the solar system from high-energy cosmic rays. The ribbon is roughly perpendicular to the...

When a person thinks about light, usually the first thing that will come to mind is the sun. We have been taught that the sun is the center of the solar system and thus it is the light of the world. This ball of fire that life on earth depends upon, is so massive in size that it contains 99.85% of all the matter in the Solar System, or 332,800 times that of earth. The distance from earth to the sun is 93,000,000 miles, which would take you 71 years to travel going 150 mph. The sun creates energy...

You can download the icons (zip file).

Our solar system is four and a half billion years old, but its formation may have occurred over a shorter period of time than we previously thought, says an international team of researchers from the Hebrew University of Jerusalem and universities and laboratories in the US and Japan. Establishing chronologies of past events or determining ages of objects require having clocks that tick at different paces, according to how far back one looks. Nuclear clocks, used for dating, are based on the rate of decay of an atomic nucleus expressed by a half-life, the time it takes for half of...

For the first time, scientists have captured images of auroras above the giant ice planet Uranus, finding further evidence of just how peculiar a world that distant planet is. Detected by means of carefully scheduled observations from the Hubble Space Telescope, the newly witnessed Uranian light show consisted of short-lived, faint, glowing dots – a world of difference from the colorful curtains of light that often ring Earth's poles. In the new observations, which are the first to glimpse the Uranian aurora with an Earth-based telescope, the researchers detected the luminous spots twice on the dayside of Uranus – the...

Jupiter might be having a change of heart. Literally. New simulations suggest that Jupiter's rocky core has been liquefying, melting, and mixing with the rest of the planet's innards. With this new data, astronomers hope to better explain a recent puzzling discovery of a strange planet outside of our solar system. "It's a really important piece of the puzzle of trying to figure out what's going on inside giant planets," said Jonathan Fortney, a planetary scientist at the University of California Santa Cruz who was not affiliated with the research. Conventional planetary formation theory has modeled Jupiter as a set...