NASA's Dawn spacecraft took this image of dwarf planet Ceres on February 19, 2015 from a distance of nearly 29,000 miles (46,000 kilometers). A bright spot with a dimmer companion spot can be seen. They appear to be in the same basin. Dawn will be captured into orbit around Ceres on March 6.
NASA/JPL
NASA's Dawn spacecraft took this image of dwarf planet Ceres on February 19, 2015 from a distance of nearly 29,000 miles (46,000 kilometers). A bright spot with a dimmer companion spot can be seen. They appear to be in the same basin. Dawn will be captured into orbit around Ceres on March 6.
Now playing
01:53
Mysterious Ceres images perplex NASA
NASA releases first ever ISS video shot at 8K
NASA
NASA releases first ever ISS video shot at 8K
Now playing
01:16
NASA shoots first 8K video of Earth
NASA
Now playing
00:59
Why did NASA launch 450,000 gallons of water?
In this photo released by NASA, the Northrop Grumman Antares rocket, with Cygnus resupply spacecraft onboard, launches from Pad-0A, Saturday, Nov. 17, 2018 at NASA's Wallops Flight Facility in Va. (Joel Kowsky/NASA via AP)
Joel Kowsky/NASA/AP
In this photo released by NASA, the Northrop Grumman Antares rocket, with Cygnus resupply spacecraft onboard, launches from Pad-0A, Saturday, Nov. 17, 2018 at NASA's Wallops Flight Facility in Va. (Joel Kowsky/NASA via AP)
Now playing
00:34
Watch NASA launch cargo ship into space
SANTA BARBARA, CA - OCTOBER 07: The SpaceX Falcon 9 rocket (R) separates from the space craft (L) behind the rocket trail after launching from Vandenberg Air Force Base carrying the SAOCOM 1A and ITASAT 1 satellites, as seen on October 7, 2018 near Santa Barbara, California. After launching the satellites, the Falcon 9 rocket successfully returned to land on solid ground near the launch site rather than at sea. The satellites will become part of a six-satellite constellation that will work in tandem with an Italian constellation known as COSMO-SkyMed.    (Photo by David McNew/Getty Images)
David McNew/Getty Images
SANTA BARBARA, CA - OCTOBER 07: The SpaceX Falcon 9 rocket (R) separates from the space craft (L) behind the rocket trail after launching from Vandenberg Air Force Base carrying the SAOCOM 1A and ITASAT 1 satellites, as seen on October 7, 2018 near Santa Barbara, California. After launching the satellites, the Falcon 9 rocket successfully returned to land on solid ground near the launch site rather than at sea. The satellites will become part of a six-satellite constellation that will work in tandem with an Italian constellation known as COSMO-SkyMed. (Photo by David McNew/Getty Images)
Now playing
01:09
SpaceX rocket launch lights up evening sky
JAXA astroid ryugu images
Twitter / @haya2e_jaxa
JAXA astroid ryugu images
Now playing
00:33
Robot sends new images from asteroid's surface
Massive structure on Saturn
NASA
Massive structure on Saturn
Now playing
01:05
New vortex discovered above Saturn
The SpaceX launch of a Falcon 9 rocket marks another milestone for Kennedy Space Center's Launch Complex 39-A.
NASA
The SpaceX launch of a Falcon 9 rocket marks another milestone for Kennedy Space Center's Launch Complex 39-A.
Now playing
02:00
60 years of NASA's history in 120 seconds
NASA TV
Now playing
01:39
Watch NASA launch probe that will explore sun
nasa lagoon nebula new images lon orig_00000000.jpg
NASA
nasa lagoon nebula new images lon orig_00000000.jpg
Now playing
01:19
Stunning virtual tour of the Lagoon Nebula
Artist's concept of the Solar Probe Plus spacecraft approaching the sun. In order to unlock the mysteries of the corona, but also to protect a society that is increasingly dependent on technology from the threats of space weather, we will send Solar Probe Plus to touch the sun.
Johns Hopkins University Applied Physics Laboratory/NASA
Artist's concept of the Solar Probe Plus spacecraft approaching the sun. In order to unlock the mysteries of the corona, but also to protect a society that is increasingly dependent on technology from the threats of space weather, we will send Solar Probe Plus to touch the sun.
Now playing
00:59
Listen: The sun is not silent
NASA's Goddard Space Flight Center/David Ladd
Now playing
01:26
Breathtaking virtual tour of the Moon in 4K
This composite image, derived from data collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard NASA's Juno mission to Jupiter, shows the central cyclone at the planet's north pole and the eight cyclones that encircle it.
NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM
This composite image, derived from data collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard NASA's Juno mission to Jupiter, shows the central cyclone at the planet's north pole and the eight cyclones that encircle it.
Now playing
01:02
NASA mission discovers Jupiter's inner secrets
N.R.Fuller, National Science Foundation
Now playing
00:46
'Fingerprint' of earliest light in universe detected
Now playing
00:46
'Super blue blood moon' lights up the skies
what is a black moon orig jpm_00000000.jpg
NASA
what is a black moon orig jpm_00000000.jpg
Now playing
01:04
What's in a moon's name?

Story highlights

NASA spacecraft is closing in on tiny world Ceres

New images show mysterious bright spot has a companion

CNN —  

Way out beyond Mars, but before you get to Jupiter, is a planet.

You read that right. There’s a planet between Mars and Jupiter.

You may not have heard of it, but it was discovered in 1801 – 129 years before Pluto. It originally was called a planet, then later an asteroid and now it’s called a dwarf planet.

Its name is Ceres (pronounced like series) and you’ll likely be hearing a lot more about it in the coming weeks.

Ceres is one of five named dwarf planets recognized by NASA and the International Astronomical Union (IAU). The other four are Eris, Pluto, Makemake and Haumea.

But Ceres is the first of these worlds to get a visitor from Earth: NASA’s Dawn spacecraft is arriving on March 6.

Ceres is a ‘planet’ that you’ve probably never heard of,” said Robert Mase, Dawn project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California.

Ceres may be considered a dwarf planet, but it’s “the giant of the main asteroid belt,” Dr. Marc Rayman, chief engineer and mission director of the Dawn mission, told CNN. “It is not only the largest object between Mars and Jupiter, it is the largest object between the sun and Pluto that a spacecraft has not yet visited.”

01:27 - Source: CNN/NASA
Hundreds more worlds in our solar system?

“We are tremendously excited,” Rayman said. “We have guided this robotic probe for well over seven years on an interplanetary journey of more than 3 billion miles. Along the way we sailed past Mars. We spent 14 months orbiting and scrutinizing the giant protoplanet Vesta. … Now, finally, we are on the verge of conducting the first exploration ever of the first dwarf planet.”

Images taken on February 19 when Dawn was about 29,000 miles (46,000 kilometers) from Ceres show a bright spot on Ceres and a dimmer companion amid the small world’s cratered surface. NASA says both spots appear to be in the same basin. The images are puzzling to scientists and they say they’ll have to wait until Dawn gets even closer to sort out the cause.

“We we will have to wait for better resolution before we can make such geologic interpretations,” said Chris Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles.

Rayman said Ceres’ surface is pretty beaten up and that its craters are “scars from life in the rough and tumble asteroid belt.”

Why study a beaten-up space rock? Rayman said because it’s a survivor – and a mysterious one. Made up of rock and ice, Ceres may even have liquid water deep beneath its surface – “perhaps as ponds or lakes or even oceans,” Rayman said.

Facts about Ceres

  • Discovered in 1801 by Giuseppe PiazziNamed for Roman goddess of agricultureThe word 'cereal' comes from CeresDiameter is about 590 miles (950 km)First object discovered in asteroid belt

He said Ceres “appears to have been in the process of growing to become a full-sized planet when Jupiter terminated its growth nearly 4.6 billion years ago.”

So by studying Ceres, scientists learn more about how the rest of the solar system formed. And he said, we should study Ceres because it’s there – and we need to understand the universe we live in. “We should study it because we hunger for knowledge and understanding. Grand undertakings like this nurture our spirit,” Rayman said.

Rayman said that if you had learned about the solar system 200 years ago, “you would have learned that Ceres was a planet, just as people who learned about the solar system in more recent generations learned that Pluto is.”

Speaking of Pluto, the most famous of the dwarf planets gets its own visitor in July. The New Horizons spacecraft is closing in for a flyby of Pluto and its moons.

This talk of planets and dwarf planets is still a little confusing, so here’s the most recent tally: NASA currently recognizes eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune, and the five named dwarf planets we listed earlier.

But a sixth possible dwarf planet already is on NASA’s watch list.

Called 2012 VP113, it’s believed to be one of the most distant objects in our solar system. On its Solar System Exploration website, NASA says the object was nicknamed “Biden” after Vice President Joseph Biden because of the VP in its initial designation. It will be up to the IAU to decide whether i2012 VP113 is a dwarf planet and whether it gets an official name.

But expect the numbers for planets in our solar system to keep changing. Mike Brown, the CalTech astronomy professor who helped discover dwarf planet Eris and who takes responsibility for killing off Pluto as a full-fledged planet, has his own tally listing more than 360 possible dwarf planets. And NASA has said there may be many more dwarf planets that we haven’t found yet.

So Ceres, and its cousins, may soon outnumber the traditional planets you learned about in grade school.