Because Ceres was fainter than the other known planets, it was evident that it was smaller. Nevertheless, many astronomers considered it to be a planet too. It is worth noting the significance of this. When a new chemical element was found a couple of years later, it was named cerium in tribute to the new planet Ceres. Uranus had been similarly honored with the naming of uranium.
In the six years following the discovery of Ceres, three more bodies were detected orbiting between Mars and Jupiter. So if you had been reading about all this years ago, there would have been at least two important differences from now. One is that your Internet connection would have been considerably slower. The other is that you might have learned in school or elsewhere that Ceres was a planet.
In , a planet was discovered beyond Uranus, and we call it Neptune. Nothing else of comparable size has subsequently been seen in our solar system. With scientific knowledge and technology progressing in the middle of the nineteenth century, new objects were glimpsed between Mars and Jupiter.
As more and more were seen over the years, what we now know as the main asteroid belt was gradually recognized. Terminology changed too. One of the great strengths of science is that it advances, and sometimes we have to modify our vocabulary to reflect the improved, refined view of the universe.
In fact, in , scientists named two more additions to the periodic table of the elements neptunium and plutonium. Ceres was the first body to be discovered that met the criteria established by the IAU, and Pluto was the second. Spacecraft are now on their way to both dwarf planets: Dawn to orbit Ceres years after its discovery and the wonderful New Horizons mission to fly past Pluto 85 years after it was found. We discussed this new nomenclature in some detail shortly after it was adopted.
We understand that the designation then, as now, is controversial among some scientists and the public, and there are strong emotions on this topic. We will not delve into it here nor in the blog comments below , preferring instead to focus on the extraordinary successes of science, the great power of the scientific method and the thrill of bold adventures far from home. One of the advances of science was the recognition that Ceres really is entirely different from typical residents of the main asteroid belt.
It is a colossus! There are millions upon millions of asteroids, and yet Ceres itself contains roughly 30 percent of the mass in that entire vast region of space. With an equatorial diameter of about miles kilometers , a value that Dawn will refine very soon, Ceres is the largest body between the sun and Pluto that a spacecraft has not yet visited. It is occasionally described as being comparable in size to Texas, which is like comparing a basketball to a flat sheet of paper.
Denser materials sink to the core, while less dense materials float above them. Ceres is the one and only object in the asteroid belt that grew large enough to undergo this melting and layering process. Thus, it is the only asteroid to be reclassed as a dwarf planet. As Astronomy magazine notes, not long after this reclassification, NASA launched the Dawn space mission to explore the two largest members of the asteroid belt, Vesta and Ceres.
Results from the mission confirmed that Ceres — but not smaller Vesta — underwent the melting and layering process that marks a dwarf planet.
But the Dawn mission findings have done much more than that. The melting and layering of Ceres was expected. The most conspicuous surface feature on Ceres, imaged by the Dawn probe, is a crater 57 miles across named Occator for a minor Roman harvest god who assisted Ceres. And one of the most distinct things about Occator, per Astronomy, is bright areas on its surface.
These have been identified as salt beds. And like salt beds on Earth, they indicate the former presence of water, even if the water has long since evaporated. But in a new twist, according to Earthsky. Math Review - Intro In mathematics, a proof is a sequence of statements given to explain how a conclusion is derived from premises known or assumed to be true.
Algebra - Example 1 In mathematics, algebra is one of the broad parts of mathematics, together with number theory, geometry and analysis. Recommended Videos Why was Pluto reclassified…. Why were the four giant pl…. Many of the first exoplane…. What are the primary reaso…. Share Question Copy Link.
Need the answer? Create an account to get free access. Sign Up Free. Log in to watch this video But mysteries still abound concerning that theory. For example, Dawn scientists suggested at a March press conference that Occator Crater — where the biggest bright spots are — is apparently too old for the theoryto work.
The thinking is that the salts should have been covered over in the 80 million years since Occator was formed. Dawn investigations continue in an attempt to resolve the findings.
Follow Elizabeth Howell howellspace , or Space. Original article on Space. Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community space. Elizabeth Howell is a contributing writer for Space.
She is the author or co-author of several books on space exploration. Elizabeth holds a Ph. She also holds a bachelor of journalism degree from Carleton University in Canada, where she began her space-writing career in Besides writing, Elizabeth teaches communications at the university and community college level, and for government training schools.
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