NASA’s Voyager 2 spacecraft gave humanity its first close-up look at Neptune and its moon Triton in the summer of 1989. Like an old film, Voyager’s historic footage of Triton has been “restored” and used to construct the best-ever global color map of that strange moon. The video may be watched here. The map, produced by Paul Schenk, a scientist at the Lunar and Planetary Institute in Houston, has also been used to make a movie recreating that historic Voyager encounter, which took place 25 years ago, on August 25, 1989.
The new Triton map has a resolution of 1,970 feet (600 meters) per pixel. The colors have been enhanced to bring out contrast but are a close approximation to Triton’s natural colors. Voyager’s “eyes” saw in colors slightly different from human eyes, and this map was produced using orange, green and blue filter images.
Researchers from Northwestern Univ. and the Univ. of New Mexico have reported evidence for potentially oceans worth of water deep beneath the U.S. Though not in the familiar liquid form — the ingredients for water are bound up in rock deep in the Earth’s mantle — the discovery may represent the planet’s largest water reservoir.
The presence of liquid water on the surface is what makes our “blue planet” habitable, and scientists have long been trying to figure out just how much water may be cycling between Earth’s surface and interior reservoirs through plate tectonics.
Earth, Moon are Around 60 M Years Older than Thought
Work presented at the European Association of Geochemistry’s Goldschmidt Geochemistry Conference in Sacramento, California shows that the timing of the giant impact between Earth’s ancestor and a planet-sized body occurred around 40 million years after the start of solar system formation. This means that the final stage of Earth’s formation is around 60 million years older than previously thought.
Climate Change May Explain Lack of Alien Encounters
Enrico Fermi, when asked about intelligent life on other planets, famously replied, “Where are they?” Any civilization advanced enough to undertake interstellar travel would, he argued, in a brief period of cosmic time, populate its entire galaxy. Yet, we haven’t made any contact with such life. This has become the famous “Fermi Paradox.”
So why don’t we see advanced civilizations swarming across the universe? One problem may be climate change. It is not that advanced civilizations always destroy themselves by over-heating their biospheres (although that is a possibility). Instead, because stars become brighter as they age, most planets with an initially life-friendly climate will become uninhabitably hot long before intelligent life emerges.
There are some 100 million other places in the Milky Way galaxy that could support complex life, report a group of university astronomers in the journal Challenges. They have developed a new computation method to examine data from planets orbiting other stars in the universe.
Their study provides the first quantitative estimate of the number of worlds in our galaxy that could harbor life above the microbial level.
Look for Mercury low in the west-northwest sky just after sunset at the beginning of the month. You’ll find it to the lower right of Jupiter. On June 29 and 30 try to spot Jupiter very low on the sunset horizon, below the crescent moon.
It’s easy to spot Saturn and Mars when they pair up with the moon. Mars appears to the left of the moon on June 6, directly above the moon on the 7 and to the right of the moon on the 8. And you’ll find Saturn above the moon on June 10 and 11. From a dark sky, you’ll see the constellation Scorpius rising below the moon and Saturn. At dawn, Venus is the bright object just to the left of the moon. The Pleiades star cluster should be visible just above it.
The slopes of a giant Martian volcano, once covered in glacial ice, may have been home to one of the most recent habitable environments found, so far, on the red planet, according to new research led by Brown Univ. geologists.
Nearly twice as tall as Mount Everest, Arsia Mons is the third tallest volcano on Mars and one of the largest mountains in the solar system. This new analysis of the landforms surrounding Arsia Mons shows that eruptions along the volcano’s northwest flank happened at the same time that a glacier covered the region around 210 million years ago. The heat from those eruptions would have melted massive amounts of ice to form englacial lakes — bodies of water that form within glaciers like liquid bubbles in a half-frozen ice cube.
Some of the wind turbines generating electricity on Earth today grew out of technology developed in the 1990s for settlements on Mars.
Back then at NASA’s Ames Research Center, senior research scientist David Bubenheim and his colleagues worked on designing a complete ecological system to sustain astronauts on Mars. To generate electricity for the future Martians, they developed a hybrid concept combining two renewable sources: wind and sun.
Just like Earth, Saturn has a “tail” — a magnetic one to be precise, formed from a trail of electrified gas from the Sun that flows out in the planet’s wake.
What’s more, scientists have long suspected that this “magnetotail” is responsible for dramatic aurora activity on the ringed planet — in a very similar way to a process that happens here on Earth. Now, Leicester research has produced the strongest evidence to date that backs up this theory.
Jupiter’s trademark Great Red Spot — a swirling storm feature larger than Earth — is shrinking. This downsizing, which is changing the shape of the spot from an oval into a circle, has been known about since the 1930s, but striking new NASA/ESA Hubble Space Telescope images capture the spot at a smaller size than ever before.
Jupiter’s Great Red Spot is a churning anticyclonic storm. It shows up in images of the giant planet as a conspicuous deep red eye embedded in swirling layers of pale yellow, orange and white. Winds inside this Jovian storm rage at immense speeds, reaching several hundreds of kilometers per hour.
Primeval lava flows formed the massive canyons and gorge systems on Mars. Water, by contrast, was far too scarce on the red planet to have cut these gigantic valleys into the landscape. This is the conclusion of several years of study by ETH Zürich geoscientist Giovanni Leone.
An Italian astronomer in the 19th century first described them as canali – on Mars’ equatorial region, a conspicuous net-like system of deep gorges known as the Noctis Labyrinthus is clearly visible. The gorge system, in turn, leads into another massive canyon, the Valles Marineris, which is 4,000 km long, 200 km wide and seven km deep. Both of these together would span the U.S. completely from east to west.
In May, You Won’t Have to Stay up Late to See Planets
This month’s sky will feature great views of Saturn and Mars all night long and a possible new meteor shower.
Mars dims and shrinks in diameter quite a bit this month, but it’s easy to spot high in the Southern sky. Saturn reaches opposition on May 10, rising at sunset and setting just before sunrise. This month the north side of the ring plane is tilted 21.7 degrees, providing a beautiful view of the planet’s north pole. Even through modest telescopes, you can see some detail on the pole.
In the movies, humans often fear invaders from Mars. These days, scientists are more concerned about invaders to Mars, in the form of micro-organisms from Earth. Three recent scientific papers examined the risks of interplanetary exchange of organisms using research from the International Space Station. All three, Survival of Rock-Colonizing Organisms After 1.5 Years in Outer Space, Resistance of Bacterial Endospores to Outer Space for Planetary Protection Purposes and Survival of Bacillus Pumilus Spores for a Prolonged Period of Time in Real Space Conditions, have appeared in Astrobiology Journal.
Organisms hitching a ride on a spacecraft have the potential to contaminate other celestial bodies, making it difficult for scientists to determine whether a life form existed on another planet or was introduced there by explorers. So it’s important to know what types of micro-organisms from Earth can survive on a spacecraft or landing vehicle.