Scientists Discover Closest Black Hole to Earth
2022-11-14
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1Scientists say they have discovered the closest black hole to Earth.
2Black holes are areas in space where gravity is so strong that nothing - not even light - can escape them.
3They are believed to be formed from collapsed stars.
4An international group of astronomers recently announced the discovery of the black hole, which sits about 1,600 light years from Earth.
5A light year is the distance light travels in one year.
6In space, light moves about 9.4 trillion kilometers each year.
7The researchers named the black hole Gaia BH1.
8They say it sits in the constellation of Ophiuchus.
9A constellation is a grouping of stars.
10The black hole is believed to weigh about 10 times the mass of our sun.
11The team said it is three times closer to Earth than the previous record-holder.
12The newly discovered gravitational mass was identified by observing the motion of its orbiting star.
13The star orbits the black hole at about the same distance as Earth orbits the sun.
14Kareem El-Badry is an astrophysicist with the Harvard-Smithsonian Center for Astrophysics and Germany's Max Planck Institute for Astronomy.
15He was the lead writer of a study describing the discovery in Monthly Notices of the Royal Astronomical Society.
16The black hole was first identified using the European Space Agency's (ESA) Gaia spacecraft.
17Gaia has already discovered more than 800,000 multi-star systems.
18El-Badry and his team then sought to confirm the discovery through numerous additional observations over a period of four months.
19This effort involved six different highly sensitive telescopes across the world.
20One was the 6.5-meter Magellan Baade telescope, based at the Las Campanas Observatory in Chile.
21The team also used an instrument on the Gemini North telescope, which is based in Hawaii.
22The researchers needed such telescopes to effectively observe the orbital motion of the black hole's star.
23The telescope in Chile and the Gemini instrument were able to provide the astronomers with high-resolution images.
24The telescopes also collected sensitive data on ultraviolet and near-infrared wavelengths.
25El-Badry said in a statement the Gemini observations "confirmed beyond a reasonable doubt" that the team had discovered a normal star and at least one black hole.
26El-Badry added that the black hole appears to be dormant, meaning not currently active.
27When active, black holes give off high-energy light. While dormant, they give off nothing and are difficult to identify.
28The scientists said it remains unclear how the black hole formed in our Milky Way galaxy.
29Examinations of data collected on Gaia BH1 suggests "its existence is difficult to explain" using traditional evolutionary modeling methods, said Tineke Roegiers.
30She is a project information specialist with the Gaia spacecraft team.
31The researchers said if the black hole formed the traditional way - from the gravitational collapse of a star - that star would have been at least 20 times the mass of our sun.
32This means the star would have only lived a short time, maybe only a few million years.
33If both stars had formed at the same time, the scientists say, the massive star would have quickly turned into a "supergiant" and swallowed the other star before it had a chance to fully develop.
34These differences, Roegiers said, "may indicate something important is missing from our current knowledge of black hole formation."
35El-Badry said the mystery about Earth's closest black hole presents many questions about how it formed, "as well as how many of these dormant black holes there are out there."
36He added, "I have been searching for a system like Gaia BH1 for the last four years, trying all kinds of methods - but none of them worked.
37It has been elating to see this search finally bear fruit."
38I'm Bryan Lynn.
1Scientists say they have discovered the closest black hole to Earth. 2Black holes are areas in space where gravity is so strong that nothing - not even light - can escape them. They are believed to be formed from collapsed stars. 3An international group of astronomers recently announced the discovery of the black hole, which sits about 1,600 light years from Earth. A light year is the distance light travels in one year. In space, light moves about 9.4 trillion kilometers each year. 4The researchers named the black hole Gaia BH1. They say it sits in the constellation of Ophiuchus. A constellation is a grouping of stars. The black hole is believed to weigh about 10 times the mass of our sun. The team said it is three times closer to Earth than the previous record-holder. 5The newly discovered gravitational mass was identified by observing the motion of its orbiting star. The star orbits the black hole at about the same distance as Earth orbits the sun. 6Kareem El-Badry is an astrophysicist with the Harvard-Smithsonian Center for Astrophysics and Germany's Max Planck Institute for Astronomy. He was the lead writer of a study describing the discovery in Monthly Notices of the Royal Astronomical Society. 7The black hole was first identified using the European Space Agency's (ESA) Gaia spacecraft. Gaia has already discovered more than 800,000 multi-star systems. El-Badry and his team then sought to confirm the discovery through numerous additional observations over a period of four months. This effort involved six different highly sensitive telescopes across the world. 8One was the 6.5-meter Magellan Baade telescope, based at the Las Campanas Observatory in Chile. The team also used an instrument on the Gemini North telescope, which is based in Hawaii. 9The researchers needed such telescopes to effectively observe the orbital motion of the black hole's star. The telescope in Chile and the Gemini instrument were able to provide the astronomers with high-resolution images. The telescopes also collected sensitive data on ultraviolet and near-infrared wavelengths. 10El-Badry said in a statement the Gemini observations "confirmed beyond a reasonable doubt" that the team had discovered a normal star and at least one black hole. El-Badry added that the black hole appears to be dormant, meaning not currently active. 11When active, black holes give off high-energy light. While dormant, they give off nothing and are difficult to identify. 12How did black hole form in our galaxy? 13The scientists said it remains unclear how the black hole formed in our Milky Way galaxy. Examinations of data collected on Gaia BH1 suggests "its existence is difficult to explain" using traditional evolutionary modeling methods, said Tineke Roegiers. She is a project information specialist with the Gaia spacecraft team. 14The researchers said if the black hole formed the traditional way - from the gravitational collapse of a star - that star would have been at least 20 times the mass of our sun. This means the star would have only lived a short time, maybe only a few million years. 15If both stars had formed at the same time, the scientists say, the massive star would have quickly turned into a "supergiant" and swallowed the other star before it had a chance to fully develop. 16These differences, Roegiers said, "may indicate something important is missing from our current knowledge of black hole formation." 17El-Badry said the mystery about Earth's closest black hole presents many questions about how it formed, "as well as how many of these dormant black holes there are out there." 18He added, "I have been searching for a system like Gaia BH1 for the last four years, trying all kinds of methods - but none of them worked. It has been elating to see this search finally bear fruit." 19I'm Bryan Lynn. 20Bryan Lynn wrote this story for VOA Learning English, based on reports from the Center for Astrophysics, The Associated Press, the European Space Agency and the Max Planck Institute for Astronomy. 21______________________________________________________________ 22Words in This Story 23doubt - n. the feeling of being unsure about something 24evolution - n. the way in which living things change and develop over millions of years 25supergiant - n. an extremely large star that is from 10,000 to 100,000 times brighter than the sun 26indicate - v. to suggest something 27elate - adj. extremely happy and excited 28bear fruit - idiom. if something bears fruit, it produces successful results 29_________________________________________________________________ 30What do you think of this story? We want to hear from you. We have a new comment system. Here is how it works: 31Each time you return to comment on the Learning English site, you can use your account and see your comments and replies to them. Our comment policy is here.