原田英語の時事英語ジュニア｜英語ニュース ワークシート（高校生レベル）
Class ____ No. ____ Name ____________________
白色矮星とは？約8分ごとに電波を出す「死んだ星」、太陽に似た星とペアとみられる
A Dead Star and a Sun-Like Partner May Be Behind an Eight-Minute Radio Signal
1Astronomers say they have traced a radio signal that repeats about every eight minutes to an unusual pair of stars. The pair sits more than 5,000 light-years from Earth. One of the stars is a white dwarf, the small, dense core that remains after a star has died. Its partner is a G-type star, the same type as our Sun.
2The flashes arrive about every 7.9 minutes. Signals that repeat this slowly are known as long-period transients. Only about 12 are known so far, and astronomers have been working to explain them for several years. Several earlier signals came from a white dwarf paired with a red dwarf. A red dwarf is a star that is smaller and cooler than the Sun.
3The team is not yet sure exactly where the radio waves start. The researchers said the flashes come from an area near the white dwarf. The source might even be the white dwarf. Astronomers still do not fully understand what causes long-period transients.
4A team led by Curtin University in Australia described the system in the journal Nature Astronomy on November 12. The study's lead author is Sam McSweeney. The Murchison Widefield Array, a radio telescope in Western Australia, first detected the flashes in late 2024. The MeerKAT telescope in South Africa then narrowed down their position in the sky. The Keck Observatory in Hawaii studied the light of the Sun-like star.
Words 単語
| tracedB1 | 動 | （出どころを）たどってつきとめたfound where something came from |
| unusualA2 | 形 | めずらしい、ふつうでないdifferent from what you often see |
| remainsB2 | 動 | 残るstays after other parts are gone |
| detectedB2 | 動 | 見つけた、感知したnoticed something that is hard to see or hear |
| coreB2 | 名 | 芯、中心部分the middle part of something |
| journalB1 | 名 | 学術誌a magazine where scientists share their studies |
| authorA2 | 名 | 著者、書いた人the person who writes a book or paper |
| narrowed downB1 | 動 | しぼりこんだmade a list of choices smaller |
| observatory外 | 名 | 天文台a building with big tools for watching the sky |
| fullyA2 | 副 | 完全に、すっかりcompletely, with nothing missing |
単語のレベル：CEFR-J（『CEFR-J Wordlist Version 1.6』 東京外国語大学投野由紀夫研究室. （URL: https://www.cefr-j.org/download.html より 2026年8月ダウンロード））
1. Reading Quiz 本文の内容に合うものを選ぼう
About how often does the radio signal repeat?
A. About every 7.9 secondsB. About every 79 secondsC. About every 7.9 minutesD. About every 7.9 hours
What kind of star is the white dwarf's partner?
A. A red dwarfB. A G-type star like the SunC. Another white dwarfD. A giant star that is dying
Which telescope first detected the flashes?
A. The Keck ObservatoryB. The MeerKAT telescopeC. A telescope in spaceD. The Murchison Widefield Array
What did the MeerKAT telescope do?
A. It narrowed down the position of the flashes in the sky.B. It studied the light of the Sun-like star.C. It first detected the flashes in late 2024.D. It found the first long-period transient in 2022.
Which sentence about earlier long-period transients is true?
A. All of them came from Sun-like stars.B. Several came from a white dwarf paired with a red dwarf.C. Hundreds of them have been found.D. Astronomers fully understand what causes them.
2. True or False 正しければ T、違っていれば F
( ) The pair of stars is less than 5,000 light-years from Earth.
( ) Astronomers are sure that the flashes come from the white dwarf itself.
( ) Only about 12 long-period transients are known so far.
( ) The study appeared in the journal Nature Astronomy.
3. Fill in the Blanks 下の語から選んで空らんをうめよう（形を変えずに）
detectedremainsauthorjournalObservatorytraced
A team led by Curtin University in Australia described the system in the _____ Nature Astronomy on November 12.
The Keck _____ in Hawaii studied the light of the Sun-like star.
One of the stars is a white dwarf, the small, dense core that _____ after a star has died.
Astronomers say they have _____ a radio signal that repeats about every eight minutes to an unusual pair of stars.
The Murchison Widefield Array, a radio telescope in Western Australia, first _____ the flashes in late 2024.
The study's lead _____ is Sam McSweeney.
4. Word Order 語を並べかえて正しい文にしよう
( Earth / than / sits / light-years / more / The / 5,000 / pair / from ) .
( Sam / is / The / study's / lead / McSweeney / author ) .
( even / white / source / might / be / the / dwarf / The ) .
5. Think and Write 英語で答えてみよう
Should countries spend a lot of money on huge radio telescopes? Why or why not?（国は大きな電波望遠鏡にたくさんのお金を使うべきだと思いますか？それはなぜ？）
Scientists sometimes wait years for an answer. Would you enjoy that kind of work?（科学者は答えが出るまで何年も待つことがあります。あなたはそういう仕事を楽しめると思いますか？）
Answers 解答
1. (1) C (2) B (3) D (4) A (5) B
2. (1) F (2) F (3) T (4) T
3. (1) journal (2) Observatory (3) remains (4) traced (5) detected (6) author
4.
- The pair sits more than 5,000 light-years from Earth.
- The study's lead author is Sam McSweeney.
- The source might even be the white dwarf.
全文訳
1約8分ごとにくり返す電波の信号は、めずらしい星のペアから来ていると、天文学者たちが発表しました。そのペアは、地球から5000光年以上はなれたところにあります。星の1つは白色矮星で、星が一生を終えたあとに残る、小さくてぎゅっとつまった芯です。その相手は、太陽と同じ種類の「G型星」です。
2電波は約7.9分ごとに届きます。このくらいゆっくりくり返す信号は「長い周期の電波トランジェント」と呼ばれています。見つかっているのはまだ約12個だけで、天文学者たちは何年も前からその正体を説明しようとしてきました。以前に見つかった信号のいくつかは、白色矮星と赤色矮星のペアから来ていました。赤色矮星とは、太陽より小さくて温度の低い星です。
3研究チームは、電波が正確にどこから出ているのか、まだはっきりわかっていません。研究者たちは、電波は白色矮星の近くから出ていると話しています。電波を出しているのは、白色矮星そのものかもしれません。長い周期の電波トランジェントが何によって起きるのか、天文学者たちはまだ完全にはわかっていません。
4オーストラリアのカーティン大学を中心とするチームが、11月12日に学術誌『ネイチャー・アストロノミー』でこの星のペアについて発表しました。論文の筆頭著者はサム・マクスウィーニーさんです。西オーストラリア州にある電波望遠鏡「マーチソン広視野電波干渉計（MWA）」が、2024年の終わりごろに初めてこの電波を見つけました。そのあと、南アフリカの望遠鏡ミーアキャットが、電波が来る空の位置をしぼりこみました。ハワイのケック天文台は、太陽に似た星の光を調べました。
文法ポイント：関係代名詞 that（主格）
that のあとに動詞が続き、前の名詞を説明する。本文の a radio signal that repeats about every eight minutes（約8分ごとにくり返す電波の信号）や a star that is smaller and cooler than the Sun（太陽より小さくて温度の低い星）がその例。
出典：The Conversation、Phys.org (ICRAR)、Gizmodo ほか（記事は原田英語の時事英語ジュニアのオリジナル）｜https://www.haradaeigo.com/jijieigo-junior/news/2026-11-14-radio-signal-every-8-minutes/