25.4k views
4 votes
Sunlight takes 8.4 minutes to get from the Sun to Earth. When NASAʹs New Horizons Spacecraft passed Pluto

in 2016, it was 33 AU from Earth. How long did it take for its transmitted images of Pluto to arrive at Earth?

A) 277.3 hours
B) 4.6 hours
C) One Plutonian year
D) They arrived almost instantaneously. The transmitted signals were radio signals and therefore traveled
at the speed of light.

1 Answer

3 votes

Final answer:

The transmission of images from NASA's New Horizons Spacecraft at Pluto to Earth took approximately 4.44 hours. This was calculated using the distance of 32 astronomical units and the speed of light, which is 1.08 × 10⁹ km/hr.

Step-by-step explanation:

The question revolves around the time it takes for a signal to travel from NASA's New Horizons Spacecraft at Pluto to Earth. To find this duration, we will use the fact that light (and radio waves, which are a form of light) travels at a constant speed through the vacuum of space. The speed of light is approximately 1.08 × 10⁹ km/hr (which is about 299,792,458 meters per second).

The distance between Earth and Pluto at the time of the New Horizons flyby in July 2015 was about 32 AU, with one astronomical unit (AU) being the average distance from Earth to the Sun, roughly 150 million km. Thus, we can calculate the distance in kilometers:

Distance = 32 AU × 150 million km/AU = 4.8 billion km

To find the time it takes for light to travel this distance, we need to divide the distance by the speed of light:

Time = Distance / Speed
Time = 4.8 billion km / (1.08 × 10⁹ km/hr)

This results in the time, which, when calculated, gives you a duration of approximately 4.44 hours. Therefore, when the New Horizons transmitted images of Pluto in 2015, it took about 4.44 hours for the images to travel from the spacecraft to Earth.

User Seyed Abbas
by
7.6k points