Juventae Chasma is an enormous box canyon

Box canyon

Box Canyon is a Box canyon in Ouray County, Colorado, United States. It was originally founded as a mining camp and helped the city of Ouray establish itself as a permanent community. Box Canyon is home to Box Canyon Falls, a 285-foot waterfall, with quartzite walls that extend almost one hundred...

 (250 km × 100 km) on Mars

Mars

Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...

 which opens to the north and forms the outflow channel Maja Valles

Maja Valles

Maja Valles is a large, ancient outflow channel in the Lunae Palus quadrangle on Mars. Its location is 12.6° north latitude and 58.3° west longitude. The name is a Nepali word for "Mars". Maja Valles begins at Juventae Chasma. Parts of the system have been partially buried by thin volcanic debris...

.

Juventae Chasma is located north of Valles Marineris

Valles Marineris

Valles Marineris is a system of canyons that runs along the Martian surface east of the Tharsis region...

 and cuts more than 5 km into the plains of Lunae Planum. The floor of Juventae Chasma is partly covered by sand dunes. There is also a 2.5 km high mountain inside Juventae, 59 km long and 23 km wide, that was confirmed by Mars Express

Mars Express

Mars Express is a space exploration mission being conducted by the European Space Agency . The Mars Express mission is exploring the planet Mars, and is the first planetary mission attempted by the agency. "Express" originally referred to the speed and efficiency with which the spacecraft was...

 to be composed of sulfate

Sulfate

In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...

 deposits. MRO

MRO

-Operations:* maintenance, repair, and operations -Companies:...

discovered sulfates, hydrated sulfates, and iron oxides in Juventae Chasma.