Answer:
According to the travellers, Alpha Centauri is <em>c) very slightly less than 4 light-years</em>
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Explanation:
For a stationary observer, Alpha Centauri is 4 light-years away but for an observer who is travelling close to the speed of light, Alpha Centauri is <em>very slightly less than 4 light-years. </em>The following expression explains why:
v = d / t
where
- v is the speed of the spaceship
- d is the distance
- t is the time
Therefore,
d = v × t
d = (0.999 c)(4 light-years)
d = 3.996 light-years
This distance is<em> very slightly less than 4 light-years. </em>
Full moon!
when Earth is exactly between the Moon and Sun, Earth's shadow falls upon the surface of the Moon, dimming it and sometimes turning the surface red over the course of a few hours.
Eris is slightly more massive than Pluto. However, both of them are smaller than Earth's Moon.
This should conclude that Eris is a dwarf planet.
