NASA’s discovery mission Dawn has recently found ice craters on a dwarf planet called Ceres. It appears the rocky planet has several shadowed regions in which its craters become ice traps and hold ice water.

Scientists have been alerted of possible ice water deposits on the dwarf planet, by studying its structure thanks to NASA’s Dawn mission. For a long time, researchers have rumored these ice traps in Ceres and this recent discovery might prove it.

Scientists have found craters that are permanently in shadow (marked blue). These are located at the poles of Ceres. Credit: NASA

According to researcher Norbert Schorghofer, the dwarf planet’s conditions are more than capable of holding ice deposits. Also, Ceres mass allows itself to hold water molecules in its structure.

“The conditions on Ceres are right for accumulating deposits of water ice, Ceres has just enough mass to hold on to water molecules, and the permanently shadowed regions were identified as extremely cold,” said investigator Schorghofer in a press release.

Ice traps on the dwarf planet

Giuseppe Piazzi discovered this rocky and icy planet in 1801. At first, it was considered a planet, until it was declared an asteroid in the 1850s. Previous investigations have shown that Ceres has a diameter around 945 kilometers.

Dwarf planet Ceres is considered the largest object in the asteroid belt located between Jupiter and Mars, making it the largest of dwarf planets in the orbit of Neptune. It is also the only known planet, on the belt, to round its own gravity.

The planet has shadowed regions on its poles, meaning the light of the sun doesn’t directly hit them and making it possible for these ice traps to appear. However, researchers said the sunlight can indirectly hit them.

Researchers have known the dwarf planet has severe cold conditions. If a shadow crater remains below -240 degrees Fahrenheit a cold trap appears. This means the planet has been collecting ice for billions of years.

Thanks to NASA’s Dawn mission images, researchers were able to study the dwarf planet’s poles, specifically, the northern hemisphere in which they observed craters, plains, and its structure.

Later on, the team identified the areas of the planet that received direct contact with the sunlight, and study the environmental conditions of Ceres through a year (1,682 days).

The largest shadowed region discovered by the research team was located in a 16 kilometers crater 40 miles from the planet’s north pole. After investigations, researchers determined 1,800 kilometers of the planet belong to shadowed regions.

“On Ceres, these regions act as cold traps down to relatively low latitudes,” said guest investigator Erwan Mazarico, who assures the dwarf planet is colder than Mercury and the Earth’s moon.

Researchers have studied water molecules on Ceres for the last couple of years. On January 2014, investigations showed emissions of water vapor in different regions of the planet, which is a rare event for an asteroid.

The main researcher of Dawn’s mission, Chris Russell, assures the planet might have a greater reservoir of water than the moon and that Mercury, because of its ice structures and locations.

NASA is hoping its high-quality images can help researchers understand more about this dwarf planet, its origins, structure, environment, and functioning.

The study results were published in the journal Geophysical Research Letters.

NASA’s Dawn mission

NASA’s main objective is to study the unknown, that’s why the Dawn mission was created on 2011 when it first explored a protoplanet called Vesta for a year. Currently, it’s exploring around Ceres.

Since its launched from Cape Canaveral in Florida, the Dawn probe is investigating different processes, conditions, environments and behaviors of the dwarf planet. NASA hopes to create a large database of the explored planets.

The Dawn mission discovered several spots on Ceres surface, thanks to its high-quality images. It was then confirmed the planet’s spots were some kind of materials containing salts and possibly water.

On December 2015, researchers informed the spots on the dwarf planet belonged to a type of salt form of brine, which contained magnesium sulfate and was associated with a rock called ammonia-rich clays.

The mission became the first spacecraft to surround and enter the orbit of a dwarf planet on March 2015. Since its launch, the spacecraft has traveled over 3.5 billion miles, orbiting 2,450 times around protoplanets Vesta and Ceres and capturing over 69,000 images.

NASA’s spacecraft was made with an ion propulsion system to allow a perfect travel. Since 2007, it has recorded over 48,000 hours of outer space environments and structures, such as Ceres and protoplanets.

The asteroid belt is now being investigated, thanks to NASA’s images collected by the Dawn spacecraft. Protoplanet Vesta was known to be a dry body after researchers studied the data collected by the machine and Cere 25 percent, water mass was determined for the same reasons.

Source: NASA