Updates on NASA’s Dawn Probe orbiting around the dwarf planet Ceres

NASA’s Dawn Probe is orbiting around the dwarf planet Ceres. The exciting part is that it is about to get closer to the planet than ever before. In the early part of the next month, Dawn will finally enter its final orbit. After entering the elliptical path, it will be ten times closer to Ceres than it has ever been in its history.

This feat will also bring an end to the Dawn mission which has been running successfully since over a decade now. After its launch, Dawn traveled years to enter the asteroid belt between Mars and Jupiter. The first coverage was on an asteroid named Vesta in 2011. It stayed in the orbit of Vesta for a year. Subsequently, it entered the orbit of the dwarf planet. Dawn’s premiere entry in the orbit of Ceres took place in March 2015. It has more than a year since Dawn is studying this object. This spacecraft mission was supposed to end in June 2016 officially. However, keeping in mind the remarkable success of the same, the mission team sought to extend it and further send it to Adeona. However, NASA recognised studying Ceres in further details to be more important than spreading the coverage of the mission. Thus, the location of Dawn remained unchanged.

NASA diagram shows the initial orbit of the Dawn spacecraft around Ceres
NASA diagram shows the initial orbit of the Dawn spacecraft around Ceres (outer green ellipse) and its near-final orbit (center green ellipse), with the blue lines indicating the probe’s path in between. Image Credit: NASA/JPL-Caltech

Entering the closest orbit is the last phase of the discussed mission. In this phase, the spacecraft will come up to 35 km close to the dwarf planet at times. This close distance will allow Dawn to capture the surface of Ceres in high resolution. This step will further help in analyzing what exactly Ceres is made up of. The spacecraft even has an instrument employed which closely detects neutrons and gamma rays radiating from the surface of Ceres. These particles can tell a lot about the material that forms Ceres. Information about the same can be gathered in a much better manner when the spacecraft is so close to the surface of the subject. This information can even help in drawing a chronology and studying how Ceres has evolved.

Figuring out the way to make into such a tight and elliptical orbit was undoubtedly a Herculean task for the mission team. It was challenging because Dawn has only moved in circular paths around Ceres before this. Also, it is tough to stay in a stable orbit when you are so close to a dwarf planet. This difficulty is because though a dwarf planet is big enough to have a gravitational pull of its own, the drag is quite less, and outside forces can still influence the spacecraft. Take, for instance, the highly energetic particles of the Sun which can quickly push and pull Dawn and thus knock it off its path.

The probe can remain in this orbit for up to 50 years. The only drawback here is that the spacecraft will not be able to stay in contact with Earth for a substantial duration now. The vehicle will soon run out of power when it exhausts its fuel.

What will happen to Dawn after 50 years? This question is still unanswered, and the analysis regarding that has not been made by experts yet. There are speculations that the spacecraft may stick around Ceres as a permanent satellite. It might keep circling without many changes. There is also a lingering hope that sometime in future when such an expedition is underway again, the experts will still be able to observe Dawn circling Ceres.