New View of Venus Reveals Previously Hidden Impact Craters

A synthetic aperture radar image of Haastte-baad Tessera, cut by a set of unique concentric rings that record a newly recognized type of impact crater on Venus, previously only identified on the icy moons of Jupiter. Credit: NASA.

Think of the Moon and most people will imagine a barren world pockmarked with craters. The same is likely true of Mars albeit more red in colour than grey! The Earth too has had its fair share of craters, some of them large but most of the evidence has been eroded by centuries of weathering. Surprisingly perhaps, Venus, the second planet from the Sun does not have the same weathering processes as we have on Earth yet there are signs of impact craters, but no large impact basins! A team of astronomers now think they have secured a new view on the hottest planet in the Solar System and revealed the missing impact sites. 

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Titan May Have a Methane Crust 10 Km Thick

Color-composite image of Titan and Saturn. There are few confirmed craters on Titan, and the ones that have been spotted are much shallower than expected. Image Credit: NASA/JPL/SSI/J. Major

Saturn’s moon, Titan, is an anomaly among moons. No other moons have surface liquids, and aside from Earth, it’s the only other Solar System object with liquids on its surface. However, since Titan is so cold, the liquids are hydrocarbons, not water. Titan’s water is all frozen into a surface layer of ice.

New research suggests that under the surface, Titan is hiding another anomaly: a thick crust of methane.

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A New Rover Design Could Crawl Across the Moon for Decades Harvesting Water

A view of the ice-mining Lunar rover and its main components.

We have known that water ice exists on the Moon since 1998. These large deposits are found in the permanently shadowed craters around the polar region. The challenge is how to get it since shadowed craters are not the best place for solar powered vehicles to operate. A team of engineers have identified a design for an ice-mining vehicle powered by americium-241. With a half-life of 432 years, this element is an ideal power source for a vehicle to operate in the dark for several decades. 

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Ouch! A Monster Asteroid Crashed Into Ganymede 4 Billion Years Ago, Rolling it Over

Artist's impression of the large impact that caused Ganymede to reorient itself 4 billion years ago. © HIRATA Naoyuki

Jupiter’s moon, Ganymede, is a fascinating celestial body. Measuring 5,268 km (3,272 mi) in diameter, it is also the largest satellite in the Solar System and even larger than Mercury, which measures 4,880 km (3,032 mi) in diameter. Like Europa, it has an interior ocean and is one of the few bodies in the Solar System (other than the gas giants) with an intrinsic magnetic field. The presence of this field also means Ganymede experiences aurorae circling the regions around its northern and southern poles due to interaction with Jupiter’s magnetic field.

In addition, based on its surface craters, scientists believe that Ganymede experienced a powerful impact with an asteroid about 4 billion years ago. This asteroid was about 20 times larger than the Chicxulub asteroid that caused the extinction of the dinosaurs, or the Cretaceous–Paleogene extinction event (ca. 66 million years ago). According to a recent study by Naoyuki Hirata of Kobe University, this impact occurred almost precisely on the meridian farthest away from Jupiter. This caused a reorientation of Ganymede’s rotational axis and allowed Hirata to determine exactly what type of impact took place.

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Basketball-Sized Meteorites Strike the Surface of Mars Every Day

This is an image of the first meteoroid impact detected by NASA’s InSight mission; the image was taken by NASA’s Mars Reconnaissance Orbiter using its High-Resolution Imaging Science Experiment (HiRISE) camera. Image Credit: NASA/JPL-Caltech/University of Arizona

NASA’s InSight Mars Lander faced some challenges during its time on the red planet’s surface. Its mole instrument struggled to penetrate the compacted Martian soil, and the mission eventually ended when its solar panels were covered in dust. But some of its instruments performed well, including SEIS, the Seismic Experiment for Interior Structure.

SEIS gathered Mars seismic data for more than four years, and researchers working with all of that data have determined a new meteorite impact rate for Mars.

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Volcanic Plumes Rise Above Lava Lakes on Io in this Juno Image

Juno's JunoCam instrument captured this image of two plumes rising from Io's surface. The image was taken from a distance of 3,800 km away. Image Credit: NASA/JPL-Caltech/SwRI/MSSS Image processing by Andrea Luck (CC BY)

As the most volcanic object in the Solar System, Jupiter’s moon Io attracts a lot of attention. NASA’s Juno spacecraft arrived at the Jovian system in July 2016, and in recent months, it’s been paying closer attention to Io.

Though Io’s internal workings have been mostly inscrutable, images and data from Juno are starting to provide a fuller picture of the strange moon’s volcanic inner life.

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Ice Deposits on Ceres Might Only Be a Few Thousand Years Old

NASA's Dawn spacecraft captured this approximately true-color image of Ceres in 2015 as it approached the dwarf planet. Dawn showed that some polar craters on Ceres hold ancient ice, but new research suggests the ice is much younger. Image Credit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDA / Justin Cowart
NASA's Dawn spacecraft captured this approximately true-color image of Ceres in 2015 as it approached the dwarf planet. Dawn showed that some polar craters on Ceres hold ancient ice, but new research suggests the ice is much younger. Image Credit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDA / Justin Cowart

The dwarf planet Ceres has some permanently dark craters that hold ice. Astronomers thought the ice was ancient when they were discovered, like in the moon’s permanently shadowed regions. But something was puzzling.

Why did some of these shadowed craters hold ice while others did not?

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Early Mars Climate was Complex, with Streams Flowing Intermittently for Millions of Years

This figure from new research shows an unnamed river valley network on Mars. By dating the craters in the image, a researcher at the Planetary Science Institute was able to determine when the river channels were formed. Image Credit: MOLA MEGDR, NASA/USGS; THEMIS mosaic, ASU/NASA/USGS; CTX, NASA/MSSS.

There’s overwhelming evidence that Mars was once wet and warm. Rivers flowed across its surface and carved intricate channel systems revealed by our orbiters. Expansive oceans even larger than Earth’s may have covered a third of its surface. Then something happened: Mars lost its atmosphere, cooled down, and surface water disappeared.

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New Photos Show Collapsed Chains of Craters on a Martian Volcano

This image from ESA’s Mars Express shows the southern flanks of Ascraeus Mons, the second-tallest volcano on Mars. Credit: ESA/DLR/FU Berlin,.

Most everyone is familiar with Olympus Mons, the largest volcano on Mars and also the largest in the Solar System. But there are several other enormous shield volcanoes on Mars. The second largest is Ascraeus Mons, and new images from ESA’s Mars Express spacecraft reveal some interesting features on the side or flank of the mountain.

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There's a Crater on Mars That Looks Like a Bear

A bear on Mars? Credit: NASA/JPL-Caltech/UArizona.

Facial pareidolia is the human tendency or illusion of seeing facial structures in an everyday objects – such as seeing the “man in the Moon,” or the face of Jesus on a piece of toast. But here’s a newly found crater on Mars that might be a case of ‘bear-adoilia.’

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