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[00:00.04]Two chemical compounds necessary to living organisms

[00:04.68]have been found in material from the asteroid Ryugu.

[00:09.88]The Japanese spacecraft Hayabusa2

[00:13.80]collected the materials and sent them back to Earth.

[00:19.32]The findings from an international group of scientists

[00:23.36]support the idea that some elements of life

[00:27.36]arrived on Earth from asteroids billions of years ago.

[00:33.24]Scientists said on Tuesday

[00:36.08]they discovered uracil and niacin

[00:39.68]in rocks collected by a Japanese Space Agency aircraft.

[00:45.48]The samples came from two places on Ryugu in 2019.

[00:52.60]Uracil is one of the chemicals present in RNA.

[00:57.16]RNA is a molecule carrying directions

[01:01.60]for building and operating living organisms.

[01:05.92]Niacin, also called Vitamin B3 or nicotinic acid,

[01:11.40]is important for metabolism.

[01:15.68]The Ryugu samples traveled 250 million kilometers back to Earth

[01:21.56]and returned to Earth's surface in a container.

[01:26.16]The container landed in December 2020 in Australia.

[01:32.96]Scientists, for a long time, have aimed to understand

[01:37.72]the conditions necessary for life on Earth

[01:40.72]after it formed about 4.5 billion years ago.

[01:46.16]Bodies like comets, asteroids and meteorites

[01:50.72]struck the Earth at that time.

[01:53.68]The new findings support the theory

[01:56.44]that those bodies provided the planet

[01:59.28]with compounds that helped create the first organisms.

[02:05.36]Scientists had found organic molecules in meteorites found on Earth.

[02:11.84]But it was not clear whether those space rocks

[02:16.24]had been affected by Earth's environment after landing.

[02:21.72]"We suspect (uracil and niacin)

[02:24.96]had a role in...evolution on Earth

[02:27.84]and possibly for the emergence of first life,"

[02:32.08]said astrochemist Yasuhiro Oba of Hokkaido University in Japan.

[02:39.08]An astrochemist studies chemistry in places other than Earth.

[02:45.40]He is lead writer of the research published

[02:49.20]in Nature Communications.

[02:53.04]RNA is short for ribonucleic acid.

[02:57.64]Uracil is necessary to form RNA,

[03:01.56]a group of molecules present in all living cells

[03:05.96]and very important for the activity of genes.

[03:10.32]RNA is similar to DNA, the molecules

[03:15.00]that carry an organism's genetic instructions.

[03:19.40]Niacin is important for metabolism

[03:22.56]and can help produce the "energy"

[03:25.32]that powers living organisms.

[03:28.80]Oba said uracil and niacin

[03:32.44]were found at both landing sites on Ryugu.

[03:36.32]The asteroid is about 900 meters in diameter

[03:41.12]and is considered a near-Earth asteroid.

[03:44.32]The amounts of the compounds

[03:46.92]were higher at one of the places

[03:49.00]than the other on the asteroid.

[03:52.84]Asteroids are rocky space bodies

[03:56.00]that formed in the early period of the solar system.

[04:00.20]The researchers suggest

[04:02.72]that the organic compounds found on Ryugu

[04:06.68]may have been formed with the help of chemical reactions

[04:10.76]caused by starlight in icy materials in space.

[04:15.08]I'm Dan Novak.

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Words in This Story

asteroid — n. a large group of small bodies that orbit the sun

metabolism — n. the process in living cells of producing energy and new substances

role — n. the part that something plays in a process or activity

evolution — n. the theory that changes in plants and animals happen because of natural processes over long periods of time

emergence — n. the act of becoming seen or coming into existence

instructions –n. (often pl.) a set of statements, letters or codes that enable something to be done