# Space & Astronomy Expert

https://hienglishquiz.com/vocabulary/science-technology-c2-space-and-astronomy-vocab

- CEFR: C2 (Proficient)
- Theme: Science & Technology
- Words: 22
- Premium: no
- Locked: no

Space vocabulary such as dark matter, event horizon and redshift, plus barycentre, nucleosynthesis and heliopause. Words for describing cosmology at an expert…

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## Word list

* **celestial** /səˈlɛstʃəl/: Belonging to the sky and to the objects that move across it, seen from the ground. — “Sailors once navigated by **celestial** objects alone, night after night.”
* **uninhabitable** /ˌʌnɪnˈhæbətəbəl/: Impossible for people to live in, because the conditions there are far too harsh. — “Venus is **uninhabitable**: the surface is hot enough to melt lead.”
* **cosmology** /kɔzˈmɔlədʒi/: The scientific study of the origin and overall structure of the universe. — “**Cosmology** tries to explain how the universe began.”
* **dark matter**: An invisible substance in space that cannot be seen directly but is believed to make up most of the universe's mass. — “Scientists still don't fully understand **dark matter**.”
* **event horizon**: The boundary around a black hole beyond which nothing, not even light, can escape. — “Once an object passes the **event horizon**, it can never return.”
* **redshift**: A change in the light from a distant object, showing that it is moving away from us. — “The star's **redshift** proved that the universe is expanding.”
* **luminosity**: The total amount of light and energy given off by a star. — “A star's **luminosity** depends on its size and temperature.”
* **terrestrial** /tərˈɛstriəl/: Relating to the Earth, or describing a planet made of rock, like Earth. — “Mars is a **terrestrial** planet, unlike gas giants such as Jupiter.”
* **interplanetary** /ˌɪntərˈplænəˌtɛri/: Happening or existing between different planets. — “The agency is planning an **interplanetary** mission to Mars.”
* **geocentric** /ˌdʒioʊˈsɛntrɪk/: Describes an old model of the universe in which the Earth was believed to be at the centre. — “Ancient astronomers once believed in a **geocentric** universe.”
* **barycentre**: The common centre of mass that two bodies orbit. — “The **barycentre** of the Earth and Moon sits inside the Earth.”
* **sidereal**: Measured by the stars rather than by the sun. — “A **sidereal** day is about four minutes shorter than a solar one.”
* **magnetosphere**: The region round a planet controlled by its magnetic field. — “The **magnetosphere** is what keeps the atmosphere from being stripped away.”
* **perigee**: The point in an orbit closest to the Earth. — “The moon looks largest at **perigee**, which the papers call a supermoon.”
* **nucleosynthesis**: The forming of new chemical elements inside stars. — “Every atom heavier than helium comes from **nucleosynthesis**.”
* **gravitational lensing**: The bending of light by a massive object. — “**Gravitational lensing** lets astronomers see galaxies hidden behind others.”
* **circumbinary**: Orbiting two stars at once. — “A **circumbinary** planet has two sunsets and no stable seasons.”
* **astrometry**: The precise measurement of the positions of stars. — “Modern **astrometry** works to a millionth of a degree.”
* **panspermia**: The idea that life spreads between planets on rocks or dust. — “**Panspermia** moves the question rather than answering it.”
* **chromosphere**: The layer of the sun's atmosphere just above the surface. — “The **chromosphere** is only visible during a total eclipse.”
* **heliopause**: The boundary where the sun's influence ends and interstellar space begins. — “Two probes have now crossed the **heliopause** and kept transmitting.”
* **libration** /ˌlaɪˈbreɪʃən/: The slight rocking motion that lets us see a little round the moon's edge. — “**Libration** is why we see fifty-nine per cent of the lunar surface.”

## Related

- Vocabulary library: https://hienglishquiz.com/vocabulary
- Section guide: https://hienglishquiz.com/vocabulary/llms.txt