All of the bases in DNA and RNA have now been found in meteorites
More of the ingredients for life have been found in meteorites.
Space rocks that fell to Earth within the last century contain the five bases that store information in DNA and RNA, scientists report April 26 in Nature Communications.
These "nucleobases" — adenine, guanine, cytosine, thymine and uracil — combine with sugars and phosphates to make up the genetic code of all life on Earth. Whether these basic ingredients for life first came from space or instead formed in a warm soup of earthly chemistry is still not known. But the discovery adds to evidence that suggests life's precursors originally came from space, the researchers say.
Scientists have detected bits of adenine, guanine and other organic compounds in meteorites since the 1960s. Researchers have also seen hints of uracil, but cytosine and thymine remained elusive, until now.
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Uracil found in Ryugu samples:
Researchers have analyzed samples of asteroid Ryugu collected by the Japanese Space Agency's Hayabusa2 spacecraft and found uracil—one of the informational units that make up RNA, the molecules that contain the instructions for how to build and operate living organisms. Nicotinic acid, also known as Vitamin B3 or niacin, which is an important cofactor for metabolism in living organisms, was also detected in the same samples.
This discovery by an international team, led by Associate Professor Yasuhiro Oba at Hokkaido University, adds to the evidence that important building blocks for life are created in space and could have been delivered to Earth by meteorites.
"Scientists have previously found nucleobases and vitamins in certain carbon-rich meteorites, but there was always the question of contamination by exposure to the Earth's environment," Oba explained. "Since the Hayabusa2 spacecraft collected two samples directly from asteroid Ryugu and delivered them to Earth in sealed capsules, contamination can be ruled out."
"We found uracil in the samples in small amounts, in the range of 6–32 parts per billion (ppb), while vitamin B3 was more abundant, in the range of 49–99 ppb," Oba elaborated. "Other biological molecules were found in the sample as well, including a selection of amino acids, amines and carboxylic acids, which are found in proteins and metabolism, respectively." The compounds detected are similar but not identical to those previously discovered in carbon-rich meteorites.
"The discovery of uracil in the samples from Ryugu lends strength to current theories regarding the source of nucleobases in the early Earth," Oba concludes. "The OSIRIS-REx mission by NASA will be returning samples from asteroid Bennu this year, and a comparative study of the composition of these asteroids will provide further data to build on these theories."
Journal Reference:
Oba, Y., Koga, T., Takano, Y. et al. Uracil in the carbonaceous asteroid (162173) Ryugu. Nat Commun 14, 1292 (2023). https://doi.org/10.1038/s41467-023-36904-3
Related:
Building Blocks of Life Found in Meteorite Which Crashed Landed in Gloucestershire
Asteroid Material Returned by Japan Probe is Oldest Material Identified and Contains 23 Amino Acids
All Five DNA and RNA Nucleobases Found in Meteorites
(Score: 2, Interesting) by Anonymous Coward on Thursday April 28 2022, @09:03PM (2 children)
So we are the aliens?
(Score: 0) by Anonymous Coward on Thursday April 28 2022, @10:10PM
Yup. Duh.
(Score: 4, Interesting) by mcgrew on Friday April 29 2022, @01:15PM
As one of my college professors used to say when examining a busy piece of artwork: "There's less here than meets the eye." If all the components of life don't exist in a galaxy, that galaxy will have no life. To NOT find "precursors" (e.g., "crude, primitive chemicals") would be astounding.
mcgrewbooks.com mcgrew.info nooze.org
(Score: 5, Funny) by martyb on Thursday April 28 2022, @09:09PM (5 children)
All your base (pairs) are belong to us!
;)
Wit is intellect, dancing.
(Score: -1, Flamebait) by Anonymous Coward on Thursday April 28 2022, @10:20PM (1 child)
Shut your trap and get back to work, you clown.
I never bought your "medical excuse" nonsense.
(Score: 0) by Anonymous Coward on Thursday April 28 2022, @11:08PM
Spam?! Yeah, fuck me for wanting to have marty be back.
(Score: 5, Interesting) by gznork26 on Friday April 29 2022, @01:01AM (2 children)
I took the idea one step further in a First Contact story I wrote back in 2007, called "Site License". Here's the URL to the tale at my blog:
http://klurgsheld.wordpress.com/2007/06/05/site-license/ [wordpress.com]
I once read it to some fans during a story sharing session at a SF convention, and the din of side discussions suddenly went silent when I reached the end. It took a few seconds before I started to get a reaction. YMMV of course.
Khipu were Turing complete.
(Score: 2) by DannyB on Friday April 29 2022, @02:49PM (1 child)
Interesting story.
But really? Light gray text on white background?
When trying to solve a problem don't ask who suffers from the problem, ask who profits from the problem.
(Score: 2) by gznork26 on Friday April 29 2022, @07:11PM
Thanks.
The font is part of a WordPress theme, and it appears black both when editing and when I use WordPress' preview, but nonetheless it presents in grey on my phone. After selecting black in the editor, rather than the default, which was supposed to have been black as well, I saw no difference when I preview.
I suspect nargles.
Khipu were Turing complete.
(Score: 2) by captain normal on Thursday April 28 2022, @10:00PM (2 children)
https://www.youtube.com/watch?v=cRjQCvfcXn0 [youtube.com]
Everyone is entitled to his own opinion, but not to his own facts"- --Daniel Patrick Moynihan--
(Score: 2) by DannyB on Friday April 29 2022, @02:54PM (1 child)
So, uh, we are made of the waste product excreted or expelled from dying stars?
When trying to solve a problem don't ask who suffers from the problem, ask who profits from the problem.
(Score: 2) by captain normal on Friday April 29 2022, @03:09PM
Makes at least as much sense as some old guy with a white beard saying, "let there be light".
Everyone is entitled to his own opinion, but not to his own facts"- --Daniel Patrick Moynihan--
(Score: 5, Insightful) by Anonymous Coward on Thursday April 28 2022, @10:15PM (10 children)
No, it doesn't, unless you can trace the lineage of existing earthly molecules to ancient meteorites. If you can't, this only adds evidence that life's precursors are not unique to our planet and may in fact exist in abundance in space.
(Score: 0) by Anonymous Coward on Thursday April 28 2022, @10:36PM (7 children)
You're nearly there. What are planetesimals? [oxfordre.com]
(Score: 1) by khallow on Friday April 29 2022, @01:00AM (6 children)
(Score: 0) by Anonymous Coward on Friday April 29 2022, @02:21AM (5 children)
Q: After crystallization of the Earth's mantle did meteors just stop falling?
A: No [wikipedia.org]
(Score: 1, Interesting) by Anonymous Coward on Friday April 29 2022, @02:32AM
My pantry contains all the base-ingredients for making cookies.
All I know is that cookies appeared at my desk one day. It most definitely wasn't my wife. She doesn't exist and anyone who believes she does is a nutjob.
(Score: 1) by khallow on Friday April 29 2022, @02:46AM (3 children)
(Score: 0) by Anonymous Coward on Friday April 29 2022, @03:33AM (2 children)
Are you sure? [scitechdaily.com]
(Score: 2, Interesting) by khallow on Friday April 29 2022, @06:52AM (1 child)
(Score: 0) by Anonymous Coward on Friday April 29 2022, @04:29PM
Yet we do. [wikipedia.org]
(Score: 1, Touché) by Anonymous Coward on Friday April 29 2022, @12:59AM (1 child)
Um, you know, the earth kinda came from space too.
(Score: 2) by EvilSS on Friday April 29 2022, @01:23PM
(Score: 2) by MIRV888 on Friday April 29 2022, @01:11AM
for life.