How many planets are in our solar system?
AnswerEight
Pluto was reclassified as a dwarf planet in 2006.
Science · Facts & stats
System facts & stats
7 fact-checked facts about systems in space, the body and everyday life, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
What is the largest planet in the solar system?
AnswerJupiter
Jupiter is more massive than all other planets combined.
Going deeper
In the metric system, what is the base unit of mass?
AnswerKilogram
The kilogram is the SI base unit of mass.
Which digits does the binary number system use?
Answer0 and 1
Binary is base 2, using only 0 and 1.
Which body system uses glands to release hormones?
AnswerEndocrine system
Glands like the thyroid and adrenals are endocrine organs.
Expert level
About what share of the solar system's mass is in the Sun?
AnswerAbout 99.8%
Everything else together is only about 0.2 percent.
What is the organ system made up of skin, hair and nails called?
AnswerIntegumentary system
The integumentary system is the body's outer covering.
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