Xenon is element number 54, with the symbol Xe. Its name comes from xenos, the Greek word for “stranger.”
Atomic number 54131.3
XeXenonキセノン (kisenon)
Symbol
Xe
Atomic weight
131.3
Place in the table
Period 5 · Group 18
Atomic weight from the Chemical Society of Japan, “Table of Standard Atomic Weights with Four Significant Figures (2026)”.
“The stranger”
Xenon was discovered in 1898. Like neon (“new”) and krypton (“hidden”), found the same year, it is a noble gas in Group 18.
Hayabusa’s engines
The ion engines of the asteroid explorer Hayabusa turn xenon gas into ions and shoot them out at high speed using a strong electric field, pushing the spacecraft forward.
Hayabusa was the first in the world to put this kind of ion engine to practical use.
Think about it
Q1How can a spacecraft move through space just by shooting out gas?
Q2What feelings of the discoverer come through in the name “stranger”?
Q3Can you name the noble gases from the top?
There is no single right answer. Talking it over with someone at home is a good way to learn.
Did you know? — The three noble gases found in 1898 are neon (new), krypton (hidden) and xenon (stranger). All three names are Greek.