A new impact basin
will replace the existing headwall for the principal spillway outlet for erosion control.
One of the larger population of Martian sand dunes exists in the planet's southern hemisphere, near the Hellas impact basin
- one of Mars' largest and most recognizable impact basin
Many suspect it's an ancient impact basin
that, over time, has been partly filled by a thick layer of frozen nitrogen, methane, and carbon monoxide.
Scientists made the discovery as they were trying to figure out why a 1,000km wide impact basin
known as Sputnik Planitia, which contains the curious heart-shaped region, was located in its present position near Pluto's equator.
In the foreground is a region of rough, heavily cratered terrain with a large, ancient two-ring impact basin
at the bottom center of the image.
One hypothesis suggested that it was formed by a massive impact, in which case it would have been the largest impact basin
on the moon.
Ten months ago the rover landed inside a giant impact basin
near the planet's equator, a site selected because of the 3-mile-high (5-km-high) mound of layered rock rising from the crater floor.
The rover's precise location had yet to be determined, but NASA said it came to rest in its planned landing zone near the foot of a tall mountain rising from the floor of a vast impact basin
called Gale Crater, in Mars' southern hemisphere.
The Hydro Impact Basin
is 115 feet long, 90 feet wide and 20 feet deep (35 x 27 x 6 meters).
Crater floors are tilted in some areas, and the floor of the Caloris impact basin
rises above the rim in some places.
The mascon gravity anomaly in Figure 6 consists of the well-defined relatively positive 26 mGal anomaly overlying the inferred impact basin
While Mars Express fires its main engine to go into Martian orbit, Beagle 2 will head for a landing site within a large impact basin
near the planet's equator.