Miranda is a small, icy moon of Uranus and one of the most visually striking and enigmatic bodies in the solar system.

Despite its relatively small size, Miranda appears to have experienced an episode of intense resurfacing that resulted in the formation of at least three remarkable and unique surface features -- polygonal-shaped regions called coronae. 

These coronae are visible in Miranda's southern hemisphere, and each one is at least 200 km across. Arden corona, the largest, has ridges and troughs with up to 2 km of relief. Elsinore corona has an outer belt that is approx. 80 km wide, relatively smooth, and elevated above the surrounding terrain by approx. 100 m. Inverness corona has a trapezoidal shape with a large, bright chevron at its center.

An ultracompact dwarf galaxy known as M60-UCD1 harbors a supermassive black hole – the smallest galaxy known to contain such a massive light-sucking object.

The astronomers used the Gemini North 8-meter optical-and-infrared telescope on Hawaii's Mauna Kea and photos taken by the Hubble Space Telescope to discover that M60-UCD1 has a black hole with a mass equal to 21 million suns. Their finding suggests plenty of other ultracompact dwarf galaxies likely also contain supermassive black holes – and those dwarfs may be the stripped remnants of larger galaxies that were torn apart during collisions with yet other galaxies.

“Hot Jupiters” are the term for large, gaseous exoplanets in other solar systems and a new study finds they make their suns wobble as they make their way through their orbit.

Jupiters are a nice designation for a metric because it has a mass 1/1000th of that of the Sun

Researchers planted 4,200 seeds in soils expected to mimic those in potential greenhouses on Mars and on the moon. Courtesy of Wieger Wamelink

By Patricia Waldron, Inside Science

(Inside Science) -- Any explorers visiting Mars and the moon will have to boldly grow where no man has grown before.

Tonight due to powerful X-class solar flares earlier this week we may get to see the Aurora Borealis at latitudes where it usually is not visible.    The Northern Lights are the result of charged particles from the Sun interacting with Earth's magnetic field.  They ride the lines of magnetic force towards the north and south pole and release light as their acceleration changes.   

This is one of the most beautiful sights in nature. A view of the Aurora Australis from the international space station.

Venus is uninhabitable for humans yet from a distance, using statistical wobbles, a Venus-like planet and an Earth-like planet are very similar.

While the Earth has oceans of water and relatively moderate temperatures, Venus has no liquid
water and exists in a runaway greenhouse scenario where the levels of carbon dioxide are so high that the atmosphere traps all the heat. The planet is torrid but it is 95 percent the size of Earth. Right now, size is what astronomers are looking for when searching for exoplanets but size alone is not a distinguishing characteristic when sorting for a habitable one. 

Quasars are supermassive black holes that live at the center of distant galaxies. They are the most luminous beacons in the sky, and shine across the entire electromagnetic spectrum due to rapidly accreting matter in their gravitationally inescapable centers.

Quasars display a broad range of outward appearances when viewed by astronomers, reflecting the diversity in the conditions of the regions close to their centers. But despite this variety, quasars have a surprising amount of regularity in their quantifiable physical properties, which follow well-defined trends (referred to as the "main sequence" of quasars) discovered more than 20 years ago. 

The Milky Way galaxy is orbited by more than 150 globular star clusters - balls of hundreds of thousands of old stars dating back to the formation of the galaxy. In the constellation of Sagittarius (The Archer), the French comet hunter Charles Messier found one such cluster and it was given the designation Messier 54.

For more than two hundred years after its discovery Messier 54, was thought to be similar to the other Milky Way globulars, but in 1994 astronomers determined that it was actually associated with a separate galaxy — the Sagittarius Dwarf Galaxy. It was found to be at a distance of around 90,000 light-years, more than three times as far from Earth as the galactic center.

The minor controversy over whether the 38 foot wide gouge near Managua Nicaragua is a impact crater leads me to the question, how easy is it to tell by sight alone if something is an impact crater or not?  So let's play crater or not crater. 

To find the answer click the pictures and there will be a link to a source which shows that one image is a impact crater or not impact crater.  That is in cases where it's uncontroversially clear. 

The first candidate. 

2. Now the second one.