Earth & Space Science · free reference

Part 6: Exploring Space

Telescopes, Space missions, astronauts and the space station, Rockets and satellites and Careers in Earth and space science. Every fact lists its source, and you can share a link to any topic.

#telescopes

In short: Telescopes gather light so we can see faraway things. Big ones use mirrors, and space telescopes such as Hubble and Webb observe the universe from space.[1][2][3]

Facts

  • Astronomers use telescopes to see objects that are very far away.[1]
  • Most telescopes, including every big one, collect and focus light with curved mirrors.[1]
  • A telescope that uses lenses is a refracting telescope.[1]

More facts

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  • A telescope that uses mirrors is a reflecting telescope.[1]
  • A huge, nearly perfect mirror is much easier to build than a huge, nearly perfect lens.[1]
  • Mirrors are lighter than lenses, so they are easier to send into space.[1]
  • The Hubble Space Telescope launched in 1990 and has changed how we understand the universe.[2]
  • Hubble travels around Earth in low Earth orbit.[2]
  • The James Webb Space Telescope launched on December 25, 2021.[3]
  • Webb is a team project of NASA and the European and Canadian space agencies.[3]
  • Webb circles the Sun about 1.5 million kilometers (1 million miles) from Earth, at a spot called L2.[3]

Key words in three languages

(6)
EnglishSpanishPortuguese
Telescope[4]Telescopio[5]Telescópio[6]
Refracting Telescope[4]Telescopio refractor[5]Telescópio Refrator[6]
Reflecting Telescope[4]Telescopio reflector[5]Telescópio Refletor[6]
Space Telescope[4]Telescopio espacial[5]Telescópio Espacial[6]
Lens[4]Lente[5]Lente[6]
Mirror[4]Espejo[5]Espelho[6]

Each word cites a page that uses it.

Practice this

We do not have a lesson on this yet. The facts above are the teaching here.

Sources (6)
  1. NASA Space Place · How Do Telescopes Work? · spaceplace.nasa.gov/telescopes/en (page updated Apr 13, 2026; checked Oct 26, 2026)
  2. NASA Science · Hubble Space Telescope · science.nasa.gov/mission/hubble (page updated Oct 22, 2026; checked Oct 26, 2026)
  3. NASA Science · James Webb Space Telescope · science.nasa.gov/mission/webb (page updated Oct 8, 2026; checked Oct 26, 2026)
  4. IAU Office of Astronomy for Education (OAE) · Astronomy Translation Network glossary: English term list · astro4edu.org/resources/glossary/search (checked Oct 26, 2026)
  5. IAU Office of Astronomy for Education (OAE) · Glosario: lista de términos en español · astro4edu.org/es/resources/glossary/search (checked Oct 26, 2026)
  6. IAU Office of Astronomy for Education (OAE) · Glossário: lista de termos em português do Brasil · astro4edu.org/pt-br/resources/glossary/search (checked Oct 26, 2026)

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#missions-astronauts-space-station

In short: People have explored space in person, from the Apollo 11 Moon landing to crews living on the International Space Station every day since 2000.[1][2]

Facts

  • People have lived on the International Space Station without a break since November 2000.[2]
  • The station zooms at about five miles per second and circles Earth about every 90 minutes.[2]
  • In one day the crew sees 16 sunrises and 16 sunsets, because the station goes around Earth 16 times.[2]

More facts

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  • The station is 356 feet (109 meters) long, almost as long as an American football field with its end zones.[2]
  • Five space agencies from 15 countries run the station together.[2]
  • Usually about seven astronauts from different countries live on board at a time.[3]
  • When NASA last asked for astronaut applications, in 2024, more than 8,000 people applied.[3]
  • Apollo 11 landed on the Moon on July 20, 1969.[1]
  • The Apollo 11 crew was Neil Armstrong, Buzz Aldrin and Michael Collins.[1]
  • Neil Armstrong was the first person to step onto the Moon.[1]
  • The New Horizons mission flew past Pluto in 2015.[4]

Key words in three languages

(5)
EnglishSpanishPortuguese
Astronaut[5]Astronauta[6]Astronauta[7]
Space Station[5]Estación espacial[6]Estação Espacial[7]
Spacecraft[5]Nave espacial[6]Espaçonave[7]
Rover[5]Rover[6]Veículo Explorador (Rover)[7]
Apollo[5]Apolo[6]Apollo[7]

Each word cites a page that uses it.

Practice this

We do not have a lesson on this yet. The facts above are the teaching here.

Sources (7)
  1. NASA · Apollo 11 · nasa.gov/mission/apollo-11 (page updated Mar 18, 2026; checked Oct 26, 2026)
  2. NASA · International Space Station Facts and Figures · nasa.gov/international-space-station/space-station-facts-and-figures (page updated Jul 16, 2024; checked Oct 26, 2026)
  3. NASA · Astronauts · nasa.gov/humans-in-space/astronauts (page updated Oct 7, 2026; checked Oct 26, 2026)
  4. NASA Science · Pluto: Facts · science.nasa.gov/dwarf-planets/pluto/facts (page updated Apr 22, 2025; checked Oct 26, 2026)
  5. IAU Office of Astronomy for Education (OAE) · Astronomy Translation Network glossary: English term list · astro4edu.org/resources/glossary/search (checked Oct 26, 2026)
  6. IAU Office of Astronomy for Education (OAE) · Glosario: lista de términos en español · astro4edu.org/es/resources/glossary/search (checked Oct 26, 2026)
  7. IAU Office of Astronomy for Education (OAE) · Glossário: lista de termos em português do Brasil · astro4edu.org/pt-br/resources/glossary/search (checked Oct 26, 2026)

See something we should correct about “Space missions, astronauts and the space station”? Tell us.

#rockets-and-satellites

In short: Rockets fly by pushing gas out one way so they move the other way. Satellites, natural or built by people, circle planets and help us with weather and communication.[1][2]

Facts

  • Rockets work because of a rule of motion: every push creates an equal push in the opposite direction.[1]
  • A rocket shoots gas out of its engine one way, and the rocket moves the other way.[1]
  • The rocket pushes the gas, and the gas pushes back on the rocket.[1]

Practice this

More facts

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  • A rocket can only leave the launch pad by blasting gas out of its engine.[1]
  • A satellite is anything that travels around a planet or a star.[2]
  • Thousands of human-made satellites circle Earth.[2]
  • Some satellites take pictures of Earth that help forecasters predict weather and follow hurricanes.[2]
  • Others send TV signals and phone calls all over the world.[2]
  • A satellite can be natural, like our Moon, or built by people.[3]
  • The first human-made satellite, Sputnik, was about as big as a beach ball. The Soviet Union launched it on October 4, 1957.[4]

Key words in three languages

(5)
EnglishSpanishPortuguese
Orbit[5]Órbita[6]Órbita[7]
Spacecraft[5]Nave espacial[6]Espaçonave[7]
Rocket[5]Cohete[6]Foguete[7]
Satellite[5]Satélite[6]Satélite[7]
Artificial Satellite[5]Satélite Artificial[6]Satélite artificial[7]

Each word cites a page that uses it.

More practice

(3)

Members-only items are marked. The science game and the worksheets by grade are free.

Sources (7)
  1. NASA Glenn Research Center · Rocket Principles · grc.nasa.gov/www/k-12/rocket/TRCRocket/rocket_principles.html (page updated May 13, 2021; checked Oct 26, 2026)
  2. NASA Space Place · What Is a Satellite? · spaceplace.nasa.gov/satellite/en (page updated Jul 31, 2026; checked Oct 26, 2026)
  3. NASA Science · Basics of Spaceflight: Glossary · science.nasa.gov/learn/basics-of-space-flight/glossary (page updated Jan 31, 2025; checked Oct 26, 2026)
  4. NASA · Oct. 4, 1957 – Sputnik, the Dawn of the Space Age · nasa.gov/image-article/oct-4-1957-sputnik-dawn-of-space-age (page updated Oct 4, 2017; checked Oct 26, 2026)
  5. IAU Office of Astronomy for Education (OAE) · Astronomy Translation Network glossary: English term list · astro4edu.org/resources/glossary/search (checked Oct 26, 2026)
  6. IAU Office of Astronomy for Education (OAE) · Glosario: lista de términos en español · astro4edu.org/es/resources/glossary/search (checked Oct 26, 2026)
  7. IAU Office of Astronomy for Education (OAE) · Glossário: lista de termos em português do Brasil · astro4edu.org/pt-br/resources/glossary/search (checked Oct 26, 2026)

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#careers

In short: Geoscientists, meteorologists, hydrologists, astronomers, aerospace engineers and astronauts all work in Earth and space science, usually after studying science in college.[1][2][3][4][5][6]

Facts

  • Geoscientists study the physical parts of Earth, such as rocks, land and water.[1]
  • Most geoscientists start with a bachelor's (college) degree.[1]
  • Atmospheric scientists, including meteorologists, study weather and climate and make forecasts.[2]

More facts

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  • They usually need a college degree in meteorology or a similar subject.[2]
  • Astronomers study planets, stars and other objects in space.[4]
  • Astronomers who do research or teach at universities usually need a Ph.D.[4]
  • Hydrologists study water and how it moves over and under the ground.[3]
  • They usually start with a college degree in geology, hydrology or a related science.[3]
  • Aerospace engineers design, build and test airplanes, spacecraft and satellites.[5]
  • Most start with a bachelor's (college) degree in aerospace engineering or a similar subject.[5]
  • Becoming an astronaut is very competitive: more than 8,000 people applied in NASA's 2024 call.[6]

Key words in three languages

(6)
EnglishSpanishPortuguese
paleontologist[16]paleontólogo[7]paleontólogo[8]
Astronaut[9]Astronauta[10]Astronauta[11]
Astronomer[9]Astrónomo[10]Astrônomo[11]
geoscientist[1]geocientífico[17]geocientista[18]
meteorologist[2]meteorólogo[12]meteorologista[13]
hydrologist[3]hidrólogo[14]hidrólogo[15]

Each word cites a page that uses it.

Practice this

We do not have a lesson on this yet. The facts above are the teaching here.

Sources (18)
  1. U.S. Bureau of Labor Statistics, Occupational Outlook Handbook · Geoscientists · bls.gov/ooh/life-physical-and-social-science/geoscientists.htm (page updated Aug 27, 2026; checked Oct 26, 2026)
  2. U.S. Bureau of Labor Statistics, Occupational Outlook Handbook · Atmospheric Scientists, Including Meteorologists · bls.gov/ooh/life-physical-and-social-science/atmospheric-scientists-including-meteorologists.htm (page updated Aug 27, 2026; checked Oct 26, 2026)
  3. U.S. Bureau of Labor Statistics, Occupational Outlook Handbook · Hydrologists · bls.gov/ooh/life-physical-and-social-science/hydrologists.htm (page updated Aug 27, 2026; checked Oct 26, 2026)
  4. U.S. Bureau of Labor Statistics, Occupational Outlook Handbook · Physicists and Astronomers · bls.gov/ooh/life-physical-and-social-science/physicists-and-astronomers.htm (page updated Aug 27, 2026; checked Oct 26, 2026)
  5. U.S. Bureau of Labor Statistics, Occupational Outlook Handbook · Aerospace Engineers · bls.gov/ooh/architecture-and-engineering/aerospace-engineers.htm (page updated Aug 27, 2026; checked Oct 26, 2026)
  6. NASA · Astronauts · nasa.gov/humans-in-space/astronauts (page updated Oct 7, 2026; checked Oct 26, 2026)
  7. RAE-ASALE, Diccionario de la lengua española · paleontólogo · dle.rae.es/paleont%C3%B3logo (checked Oct 26, 2026)
  8. Dicionário Priberam da Língua Portuguesa · paleontólogo · dicionario.priberam.org/paleont%C3%B3logo (checked Oct 26, 2026)
  9. IAU Office of Astronomy for Education (OAE) · Astronomy Translation Network glossary: English term list · astro4edu.org/resources/glossary/search (checked Oct 26, 2026)
  10. IAU Office of Astronomy for Education (OAE) · Glosario: lista de términos en español · astro4edu.org/es/resources/glossary/search (checked Oct 26, 2026)
  11. IAU Office of Astronomy for Education (OAE) · Glossário: lista de termos em português do Brasil · astro4edu.org/pt-br/resources/glossary/search (checked Oct 26, 2026)
  12. RAE-ASALE, Diccionario de la lengua española · meteorólogo · dle.rae.es/meteor%C3%B3logo (checked Oct 26, 2026)
  13. Dicionário Priberam da Língua Portuguesa · meteorologista · dicionario.priberam.org/meteorologista (checked Oct 26, 2026)
  14. RAE-ASALE, Diccionario de la lengua española · hidrólogo · dle.rae.es/hidr%C3%B3logo (checked Oct 26, 2026)
  15. Dicionário Priberam da Língua Portuguesa · hidrólogo · dicionario.priberam.org/hidr%C3%B3logo (checked Oct 26, 2026)
  16. National Park Service, National Fossil Day · Frequently Asked Questions · nps.gov/subjects/fossilday/faq.htm (checked Oct 30, 2026)
  17. Servicio Geológico Colombiano · Vidas de ciencia (geocientíficos destacados) · www2.sgc.gov.co/geocientificos-destacados/Paginas/vidas-de-ciencia.aspx (checked Oct 30, 2026)
  18. Dicionário Priberam da Língua Portuguesa · geocientista · dicionario.priberam.org/geocientista (checked Oct 30, 2026)

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