Mars exploration
화성 탐사
Sending probes and rovers to Mars to study it, and someday sending people.
Overview
The Earth and Mars come close to each other about every 2 years and 2 months. You save fuel by leaving at those times, so launches to Mars bunch up then. The trip alone takes about seven to nine months. So far, orbiters circling the planet and rovers driving over its surface have studied the soil, the rocks and traces of water that flowed long ago.
Sending people is much harder. The round trip alone takes over a year, the crew must withstand space radiation the whole time, and if something goes wrong they cannot just come back. A signal can take over 20 minutes to arrive, so no one on Earth can help right away either. That is why people want to practice on the Moon first.
An everyday example
If the Moon is a nearby island you can reach in a few days, Mars is a far-off continent that takes months to sail to, with a ship leaving only once every two years or so.
Why it matters
Mars is the final goal of the companies that build very large rockets. Once you know that the chance to leave comes only about every two years, and that missing it pushes the whole schedule back, Mars plan news becomes easier to read.