## Breadcrumb

-  Science 
-  Science Explorer 
-  Planetary Science 

# Planetary Science 101

Planetary science is the study of planets, moons, and other small bodies in our solar system. Planetary scientists work across a wide range of fields to learn about everything from planetary atmospheres to interiors. Learn more about planetary science at the USGS below!

                  -              Overview           
                  -              Science           
                  -              News           

### What is planetary science?

Planetary science is the study of planetary processes across the solar system. Planetary scientists come from many different fields, including geology, physics, chemistry, biology, and computer science. Even though these scientists come from different backgrounds, they all use their expertise to better understand the history of our Solar System and how physical processes work on other planets, moons, and small bodies like asteroids and comets. Planetary scientists study all parts of a planetary body (the atmosphere, surface, and interior), the interactions between them, and their potential habitability.

View Media Details

### Our Solar System

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Our solar system is made up of many different planetary bodies – from solid, rocky planets like Earth and Mars, to gas giants like Jupiter, rocky or icy asteroids like Ceres, and icy moons like Enceladus – one of Saturn’s many moons. What planetary bodies are made of (their composition) depends mostly on how far away from the sun they were when they formed. Bodies that are closer to the sun – Mercury, Venus, Earth, and Mars – are solid, rocky bodies. Further away from the sun, it is much colder, and water-ice and other materials like methane are stable at the pressures and temperatures that exist on the surface of the outer satellites. These differences in composition, combined with the different geologic processes that are active on a planetary body create the wide variety of planetary surfaces we see across our solar system today.

### How are other planets and moons in our solar system similar to Earth?  

Many planetary bodies in our solar system have rocky surfaces that have evolved over time just like the surface of Earth. Planets with atmospheres are more likely to have surface processes similar to Earth because those atmospheres protect against space weathering effects like micrometeorites and radiation from the sun and outer space. All solid bodies in the solar system are affected by the same basic processes: impacts, weathering (either by wind, water, or space), and volcanism, but they look different depending on what the planetary body is made of, how big it is, and if it has an atmosphere.

Volcanoes

## Volcanoes

Weathering

## Weathering

Impacts

## Impacts

#### How are other planetary bodies different from Earth? 

Because all the bodies in the solar system are different distances from the sun, they experience very different temperature conditions. Those different temperatures, combined with the different materials that each planetary body is made of, makes some places in our solar system very different from Earth. Here on Earth, we have a water cycle that plays a major role in shaping the surface of our planet. Saturn’s moon Titan has a cycle like Earth’s water cycle, but instead of water, it’s methane and ethane that shape Titan’s surface. This means Titan has rain and lakes, but they’re made of methane instead of water. Other moons of the outer solar system have liquid water and ice, but it’s so cold that they have something Earth doesn’t - cryovolcanism. Cryovolcanism is water-ice volcanism, and is like volcanism on Earth, but the rocks are made of ice and the lava is liquid water! Check out the articles below to learn more about water across our fascinating solar system!

                                -  - linkOctober 14, 2021                Tour of Water in the Solar System              
Happy Earth Week! This year, the theme for Earth Week is Water. Let’s take a tour of the solar system and see where else water exists, and why it’s so unique that water exists in the forms that it does here on Earth! 

 
ByAstrogeology Science Center, Planetary Geologic Mapping 
- linkApril 7, 2023                USGS Scientists Follow the Water!              
The Earth has a lot of water, but that’s not the only place Astrogeology is going in search of this precious resource! Whether it’s finding water on a far-away planet, investigating ways that water can be used as a potential resource for space travel, or sharing about where water can be found in the solar system, Astrogeology scientists are heavily invested in the study of this valuable resource.
ByAstrogeology Science Center 
- linkMay 6, 2020                ‘Cereously’: An Ice Shell of Ceres keeps fiery debates burning              
In March 2015, researchers were excited as they waited for details about the dwarf planet Ceres from NASA’s Dawn mission. Further knowledge of the structure, surface, and history of Ceres were long-awaited and in acquisition. Dawn's revelation of the composition of Ceres’ 40-km-thick crust is debated among researchers despite the wealth of data collected. 
ByAstrogeology Science Center 
 

#### How do USGS scientists study the solar system? 

USGS scientists study the solar system in several different ways. Many scientists use data collected by spacecraft (remote sensing) like orbiters and rovers to observe features on different planetary bodies – but that’s just one way to study space. Sometimes they study locations here on Earth (terrestrial analogs) to better understand what similar processes could look like on other bodies. Planetary scientists also create maps of other planetary bodies to help understand their geologic history, processes, and how the different rocks relate to each other in space and time. They also simulate and test geologic processes through lab experiments and computer models. Learn more about each of these below!

Terrestrial Analogs

## Terrestrial Analogs

Remote Sensing

## Remote Sensing

Lab Analysis

## Lab Analysis

Computer Modeling and Simulations

## Computer Modeling and Simulations

Mapping

## Mapping

Learn more about planetary science at the USGS by visiting the topics on our Science Explorer page!

## News

From Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!

December 22, 2022

####   From Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!

Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!

November 23, 2022

####   Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!

Astrogeology Celebrates 10 Years of Roving with Curiosity on Mars

August 5, 2022

####   Astrogeology Celebrates 10 Years of Roving with Curiosity on Mars

View All

The USGS Astrogeology Science Center

## The USGS Astrogeology Science Center

The USGS Spectroscopy Lab

## The USGS Spectroscopy Lab

Planetary Volcanology

## Planetary Volcanology

Surface-Atmosphere Interactions

## Surface-Atmosphere Interactions

Planetary Volatiles: Snow and Ice

## Planetary Volatiles: Snow and Ice

Caves

## Caves

From Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!

December 22, 2022

####   From Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!

Do you want to know how and why scientists use terrestrial analogs to do research and explore space? Watch this quick video of physical scientist Ryan...

Read Article

Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!

November 23, 2022

####   Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!

With the Thanksgiving holiday approaching, we at Astrogeology are not only thankful for food on our tables, but for the successful launch of NASA’s...

Read Article

Astrogeology Celebrates 10 Years of Roving with Curiosity on Mars

August 5, 2022

####   Astrogeology Celebrates 10 Years of Roving with Curiosity on Mars

It’s hard to believe, but today marks 10 (Earth) years since the Curiosity rover touched down on Mars, and USGS Astrogeology has been involved with...

Read Article

A Virtual Field-trip Guide to S P Mountain Just Released by Astrogeology Science Center!

September 29, 2021

####   A Virtual Field-trip Guide to S P Mountain Just Released by Astrogeology Science Center!

If you are interested in volcanology,  you should check out our newly-released virtual S P Mountain Field Guide. S P Mountain is a textbook example of...

Read Article

Astrogeology has eyes on Mars through Mastcam-Z on Perseverance Rover

September 13, 2021

####   Astrogeology has eyes on Mars through Mastcam-Z on Perseverance Rover

Astrogeology has eyes on Mars through Mastcam-Z on Perseverance Rover. The Mars 2020 Perseverance Rover arrived on Mars' surface in February 2021...

Read Article

Mineral first identified in lunar meteorite named after former USGS Astrogeology Scientist

December 8, 2020

####   Mineral first identified in lunar meteorite named after former USGS Astrogeology Scientist

First identified in a meteorite found in Africa in 2014, the calcium-aluminum silicate mineral has been named in honor of lunar geologist and USGS...

Read Article

Sneak a Peek: What more are researchers looking for in Martian caves?

April 9, 2020

####   Sneak a Peek: What more are researchers looking for in Martian caves?

Bringing mysteries of the Martian Cave to life to aid human exploration.

Read Article

Astrogeology team finalizes work on MER mission

September 6, 2019

####   Astrogeology team finalizes work on MER mission

Spirit and Opportunity will be sorely missed.

Read Article

Next Generation Lunar Rover Visits the Astrogeology Science Center!

September 3, 2019

####   Next Generation Lunar Rover Visits the Astrogeology Science Center!

See the next generation Lunar Rover prototype!

Read Article

The Caves of Mars

July 26, 2019

####   The Caves of Mars

**The USGS Astrogeology Science Center has released locations of more than a thousand cave-entrance candidates on Mars.**

Read Article

Understanding How Jupiter’s Volcanic Moon Creates Mountains

May 19, 2016

####   Understanding How Jupiter’s Volcanic Moon Creates Mountains

Mountains on Io, Jupiter’s volcanic moon, are formed by a unique geologic mechanism not found elsewhere in the solar system, according to a new study...

Read Article

                  - Overview  What is planetary science?
Planetary science is the study of planetary processes across the solar system. Planetary scientists come from many different fields, including geology, physics, chemistry, biology, and computer science. Even though these scientists come from different backgrounds, they all use their expertise to better understand the history of our Solar System and how physical processes work on other planets, moons, and small bodies like asteroids and comets. Planetary scientists study all parts of a planetary body (the atmosphere, surface, and interior), the interactions between them, and their potential habitability.
        Sources/Usage: Public Domain. View Media DetailsOur Solar System        Sources/Usage: Public Domain. View Media Details
Our solar system is made up of many different planetary bodies – from solid, rocky planets like Earth and Mars, to gas giants like Jupiter, rocky or icy asteroids like Ceres, and icy moons like Enceladus – one of Saturn’s many moons. What planetary bodies are made of (their composition) depends mostly on how far away from the sun they were when they formed. Bodies that are closer to the sun – Mercury, Venus, Earth, and Mars – are solid, rocky bodies. Further away from the sun, it is much colder, and water-ice and other materials like methane are stable at the pressures and temperatures that exist on the surface of the outer satellites. These differences in composition, combined with the different geologic processes that are active on a planetary body create the wide variety of planetary surfaces we see across our solar system today.
How are other planets and moons in our solar system similar to Earth?  
Many planetary bodies in our solar system have rocky surfaces that have evolved over time just like the surface of Earth. Planets with atmospheres are more likely to have surface processes similar to Earth because those atmospheres protect against space weathering effects like micrometeorites and radiation from the sun and outer space. All solid bodies in the solar system are affected by the same basic processes: impacts, weathering (either by wind, water, or space), and volcanism, but they look different depending on what the planetary body is made of, how big it is, and if it has an atmosphere.
VolcanoesVolcanoesWeatheringWeatheringImpactsImpactsHow are other planetary bodies different from Earth? 
Because all the bodies in the solar system are different distances from the sun, they experience very different temperature conditions. Those different temperatures, combined with the different materials that each planetary body is made of, makes some places in our solar system very different from Earth. Here on Earth, we have a water cycle that plays a major role in shaping the surface of our planet. Saturn’s moon Titan has a cycle like Earth’s water cycle, but instead of water, it’s methane and ethane that shape Titan’s surface. This means Titan has rain and lakes, but they’re made of methane instead of water. Other moons of the outer solar system have liquid water and ice, but it’s so cold that they have something Earth doesn’t - cryovolcanism. Cryovolcanism is water-ice volcanism, and is like volcanism on Earth, but the rocks are made of ice and the lava is liquid water! Check out the articles below to learn more about water across our fascinating solar system!
-  - linkOctober 14, 2021                Tour of Water in the Solar System              
Happy Earth Week! This year, the theme for Earth Week is Water. Let’s take a tour of the solar system and see where else water exists, and why it’s so unique that water exists in the forms that it does here on Earth! 

 
ByAstrogeology Science Center, Planetary Geologic Mapping 
- linkApril 7, 2023                USGS Scientists Follow the Water!              
The Earth has a lot of water, but that’s not the only place Astrogeology is going in search of this precious resource! Whether it’s finding water on a far-away planet, investigating ways that water can be used as a potential resource for space travel, or sharing about where water can be found in the solar system, Astrogeology scientists are heavily invested in the study of this valuable resource.
ByAstrogeology Science Center 
- linkMay 6, 2020                ‘Cereously’: An Ice Shell of Ceres keeps fiery debates burning              
In March 2015, researchers were excited as they waited for details about the dwarf planet Ceres from NASA’s Dawn mission. Further knowledge of the structure, surface, and history of Ceres were long-awaited and in acquisition. Dawn's revelation of the composition of Ceres’ 40-km-thick crust is debated among researchers despite the wealth of data collected. 
ByAstrogeology Science Center 
 
How do USGS scientists study the solar system? 
USGS scientists study the solar system in several different ways. Many scientists use data collected by spacecraft (remote sensing) like orbiters and rovers to observe features on different planetary bodies – but that’s just one way to study space. Sometimes they study locations here on Earth (terrestrial analogs) to better understand what similar processes could look like on other bodies. Planetary scientists also create maps of other planetary bodies to help understand their geologic history, processes, and how the different rocks relate to each other in space and time. They also simulate and test geologic processes through lab experiments and computer models. Learn more about each of these below!
Terrestrial AnalogsTerrestrial AnalogsRemote SensingRemote SensingLab AnalysisLab AnalysisComputer Modeling and SimulationsComputer Modeling and SimulationsMappingMapping
Learn more about planetary science at the USGS by visiting the topics on our Science Explorer page!
NewsFrom Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!December 22, 2022  From Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!November 23, 2022  Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!Astrogeology Celebrates 10 Years of Roving with Curiosity on MarsAugust 5, 2022  Astrogeology Celebrates 10 Years of Roving with Curiosity on MarsView All 
                  - Science  The USGS Astrogeology Science CenterThe USGS Astrogeology Science CenterThe USGS Spectroscopy LabThe USGS Spectroscopy LabPlanetary VolcanologyPlanetary VolcanologySurface-Atmosphere InteractionsSurface-Atmosphere InteractionsPlanetary Volatiles: Snow and IcePlanetary Volatiles: Snow and IceCavesCaves 
                  - News  LabelFrom Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!December 22, 2022  From Earth to Space:  Astrogeology team tell Denver7 News how they use Terrestrial Analog sites to study our Solar System!
Do you want to know how and why scientists use terrestrial analogs to do research and explore space? Watch this quick video of physical scientist Ryan...
Read Article**Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!November 23, 2022  Astrogeology Team Reflect on Successful Artemis 1 Mission Launch: A Mission to be Thankful For!
With the Thanksgiving holiday approaching, we at Astrogeology are not only thankful for food on our tables, but for the successful launch of NASA’s...
Read Article**Astrogeology Celebrates 10 Years of Roving with Curiosity on MarsAugust 5, 2022  Astrogeology Celebrates 10 Years of Roving with Curiosity on Mars
It’s hard to believe, but today marks 10 (Earth) years since the Curiosity rover touched down on Mars, and USGS Astrogeology has been involved with...
Read Article**A Virtual Field-trip Guide to S P Mountain Just Released by Astrogeology Science Center!September 29, 2021  A Virtual Field-trip Guide to S P Mountain Just Released by Astrogeology Science Center!
If you are interested in volcanology,  you should check out our newly-released virtual S P Mountain Field Guide. S P Mountain is a textbook example of...
Read Article**Astrogeology has eyes on Mars through Mastcam-Z on Perseverance RoverSeptember 13, 2021  Astrogeology has eyes on Mars through Mastcam-Z on Perseverance Rover
Astrogeology has eyes on Mars through Mastcam-Z on Perseverance Rover. The Mars 2020 Perseverance Rover arrived on Mars' surface in February 2021...
Read Article**Mineral first identified in lunar meteorite named after former USGS Astrogeology ScientistDecember 8, 2020  Mineral first identified in lunar meteorite named after former USGS Astrogeology Scientist
First identified in a meteorite found in Africa in 2014, the calcium-aluminum silicate mineral has been named in honor of lunar geologist and USGS...
Read Article**Sneak a Peek: What more are researchers looking for in Martian caves?April 9, 2020  Sneak a Peek: What more are researchers looking for in Martian caves?
Bringing mysteries of the Martian Cave to life to aid human exploration.
Read Article**Astrogeology team finalizes work on MER missionSeptember 6, 2019  Astrogeology team finalizes work on MER mission
Spirit and Opportunity will be sorely missed.
Read Article**Next Generation Lunar Rover Visits the Astrogeology Science Center!September 3, 2019  Next Generation Lunar Rover Visits the Astrogeology Science Center!
See the next generation Lunar Rover prototype!
Read Article**The Caves of MarsJuly 26, 2019  The Caves of Mars
**The USGS Astrogeology Science Center has released locations of more than a thousand cave-entrance candidates on Mars.**
Read Article**Understanding How Jupiter’s Volcanic Moon Creates MountainsMay 19, 2016  Understanding How Jupiter’s Volcanic Moon Creates Mountains
Mountains on Io, Jupiter’s volcanic moon, are formed by a unique geologic mechanism not found elsewhere in the solar system, according to a new study...
Read Article**