Will the Universe End? Are There Endless Stars?

Questions with No Easy Answers

This is a question about space science! I haven't studied space science, so I can't answer like an expert. But I tried to learn about it myself.

Experts say that we can see up to 93 billion light-years across the universe! (A light-year is how far light travels in one year. Light zooms really fast, about 300 million meters every second! So, one light-year is a super, super long distance – about 9,460,000,000,000 kilometers!) So, the farthest we can see in space is like multiplying that huge number (9,460,000,000,000 km) by 93 billion!

What I find really interesting is that even scientists sometimes don't know everything. In elementary, middle, and high school, we usually learn things that have clear answers. So, we don't often run into questions that don't have an answer.

But in real life, and even in science, I think there are many more questions that don't have a simple answer. And scientists spend many years looking at clues and doing research to talk about these questions that don't have an answer yet. Isn't it so fun to think about these kinds of questions that don't have easy answers?

Original:

宇宙のおわりはあるのか？星の数はきりがあるのか？

答えがない問い

リさん「これは宇宙物理学という分野の問いだね。私は宇宙物理を勉強したことがないから専門家として答えることができないけれど、いろいろと自分で勉強してみたよ。専門家によると、宇宙は直径930億光年まで観測できる、という説があるそうだ。※1光年は秒速3億mで進む光が1年かかって到達する距離、つまり9兆4600億kmだ。だから観測できる宇宙の限界は「9兆4600億×930億」となるね。私がここで面白いなと思う点は、「科学者にもわからないことがある」ということだ。小中高では答えがはっきりしていることについて勉強するから「答えがない」問いには出会わない。でも、人生でも学問でも、答えがない問いの方が多いと思う。そして科学者は何年もかけて「答えがまだない」問いについて、いろいろな証拠・研究をもとに議論する。これからもっと答えのない問いについていろいろ考えてみよう。」