A space probe exploring the outer reaches of the solar system is transmitting telemetry signals back to Earth. As the probe moves directly away from Earth, its signals exhibit red-shift.
Describe how the wavelength and frequency of the radio waves received from the probe change when observed from Earth because of this red-shift.
The average orbital radius of a hypothetical Kuiper Belt object is measured to be approximately 7.3 × 104 gigametres (Gm).
Which of the following is equivalent to this distance in metres (m)?
A team of astronomers publishes a paper claiming to have observed a tenth major planet in our solar system using a novel infrared telescope, but their observations contradict existing sky surveys. Explain why it is important for these new observations to undergo peer review before they are widely accepted.