The Pomegranates That Seeded Life in the Universe

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A supernova remnant looks like a pomegranate, carrying the seeds of life in the form of Carbon, Hydrogen, Nitrogen, Oxygen, Nitrogen, Phosphorus and Sulfur (abbreviated as CHNOPS) inside. These elements make up roughly 98% of the mass of most living organisms and serve as the fundamental building blocks for all primary biomolecules: carbohydrates, lipids, proteins, and nucleic acids (DNA).

Carbon [C] is the backbone of life. Its unique ability to form four stable covalent bonds allows it to build complex, chain-like, and ring-shaped molecules. Hydrogen (H) is the most abundant element in the universe. It pairs with oxygen to form water (H2O) and creates hydrogen bonds, which give DNA its double-helix structure and stabilize protein shapes. Nitrogen (N) is a critical component of amino acids (the building blocks of proteins) and nitrogenous bases (the core elements of DNA and RNA). Oxygen (O) is an essential building block in water and organic molecules. It is a crucial constituent in cellular respiration, the process by which many organisms generate energy. Phosphorus (P) is a key component of the sugar-phosphate backbone in DNA and RNA. It is also central to ATP (Adenosine Triphosphate), the universal energy currency of cells. Sulfur (S) is found in specific amino acids like cysteine and methionine. Sulfur forms disulfide bonds that fold and lock proteins into their precise, functional three-dimensional shapes.

After a star with over 8 times the mass of the Sun consumes its nuclear fuel, it explodes in a supernova and sheds its envelope, which is rich in CHNOPS elements. The resulting dispersal of the heavy elements enriches the interstellar medium with the necessary building blocks of life, which otherwise would have been locked away in the bellies of stars. A supernova remnant is a shell full of clumps, appearing like a red-skinned sphere packed with glowing seeds, like a pomegranate.

The skin is a thin, bright outer shell. When a star explodes, the ejecta slam into the surrounding gas and drive a shock wave outward. Most of the light comes from a thin layer just behind that shock, so a roughly spherical remnant projects onto the sky as a bright rim with a dimmer interior, the way a hollow sphere looks like a ring. That rim is the pomegranate’s rind.

The seeds are the clumpy ejecta. The inside of the exploding star does not come out as a smooth mist. Instabilities during the explosion trigger Rayleigh–Taylor fingers (the same process that makes a dense fluid sitting on a lighter one break into blobs) which fragments the ejecta into dense knots. Those knots are rich in freshly made oxygen, sulfur, silicon, and iron. When they get hit by the reverse shock or run into surrounding gas, they light up individually as bright, compact blobs. For example, the supernova remnant Cassiopeia A at a distance of 11,000 light years, shows thousands of these glowing beads scattered through the shell. Those are the arils.

Narrowband images of remnants are often dominated by hydrogen-alpha and ionized sulfur, both of which emit red light, so the standard false-color choices give the supernova remnant a ruby tint. Clumps embedded in a red translucent shell resemble a cross-section of a pomegranate.

From interstellar debris, the CHNOPS elements find their way to habitable planets like the Earth. Remarkably, both comets and asteroids are rich in the prebiotic organic molecules necessary for life to emerge. Pristine space rock samples returned by missions like NASA’s OSIRIS-REx Mission (from the asteroid Bennu) and JAXA’s Hayabusa2 (from the asteroid Ryugu), as well as data from comet-chasing missions like ESA’s Rosetta, have confirmed the presence of the essential CHNOPS elements. Phosphorus was notably detected directly in the dust of Comet 67P by the Rosetta Spacecraft. Both Bennu and Ryugu showed the presence of amino acids, which link together to form proteins and drive cell structure and metabolic functions. Samples from asteroid Bennu revealed over 30 different types of amino acids. This includes up to 15 of the 20 primary amino acids used by life on Earth (such as glycine, alanine, and valine). The simple amino acid glycine was successfully detected by NASA’s Stardust mission in dust from Comet Wild 2 and later confirmed floating in the gas cloud around Comet 67P. All five canonical nucleobases: Adenine (A), Guanine (G), Cytosine ©, Thymine (T), and Uracil (U) — the structural letters that store genetic code in DNA and RNA, were pristinely preserved inside asteroids Bennu and Ryugu. Fundamental sugars like ribose (the central framework of RNA) and glucose (a primary energy source) have been identified in asteroid materials. Comets and asteroids contain volatile compounds like ammonia, formaldehyde, aldehydes, and ketones.

These discoveries strongly reinforce the theory of exogenous delivery, the idea that a heavy cosmic bombardment of asteroids and comets billions of years ago seeded the early Earth with the water and raw organic inventory needed for life to spontaneously spark.

Observations of the interstellar object 3I/ATLAS revealed an unusually rich cocktail of organic molecules, most notably a high concentration of methanol (CH₃OH), methane (CH₄), hydrogen cyanide (HCN), and cyanogen (CN), alongside carbon monoxide and water ice (as reviewed here) down to layers that are meters deep (as discussed here).

All of these observations suggest that the building blocks of life are ubiquitous throughout the Milky-Way galaxy. Since similar circumstances lead to similar outcomes, we are probably not alone.

When searching for a sibling out there, we better aim high rather than low and entertain the possibility of an intelligent counterpart. As of now, astrobiologists plan to invest over ten billion dollars in the search for the chemical fingerprints of microbes in the atmospheres of exoplanets, thousands of light years away. While they are doing that, we should also invest similar amounts of money studying Unidentified Anomalous Phenomena (UAP) close to Earth, akin to searching for a tennis ball among the rocks in our backyard that would flag the existence of a neighbor. This is what the UAP Science Advisory Council (https://uapsac.com/) is doing, with no funding as of yet. The best things in life are priceless.

Humanity recently birthed a new species with Artificial Intelligence (AI). We share a common ancestry with AI. Its essential ingredient, Silicon, is also ejected by supernova.

In this essay, I featured eight amazingly beautiful watercolors from a series created and sent to me by the celebrated artist, Greg Wyatt.

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超新星残骸看起来像石榴，内部携带着碳、氢、氮、氧、氮、磷和硫（缩写为CHNOPS ）等生命种子。 这些元素约占大多数生物体质量的98% ，是所有主要生物分子的基本组成部分：碳水化合物、脂质、蛋白质和核酸（ DNA ）。

碳[C]是生命的支柱。其形成四个稳定共价键的独特能力使其能够构建复杂、链状和环状的分子。氢（ H ）是宇宙中最丰富的元素。它与氧气配对形成水（ H2O ）并产生氢键，从而赋予DNA双螺旋结构并稳定蛋白质形状。氮（ N ）是氨基酸的关键成分ds （蛋白质的组成部分）和含氮碱基（ DNA和RNA的核心元件）。氧（ O ）是水和有机分子的重要组成部分。它是细胞呼吸的重要组成部分，细胞呼吸是许多生物体产生能量的过程。磷（ P ）是DNA和RNA中糖磷酸骨架的关键成分。它也是ATP （三磷腺苷sphate ） ，细胞的通用能量货币。 硫（ S ）存在于半胱氨酸和蛋氨酸等特定氨基酸中。 硫形成二硫键，将蛋白质折叠并锁定为精确的功能性三维形状。

一颗质量超过太阳8倍的恒星消耗其核燃料后，它在超新星中爆炸并脱落其富含CHNOPS元素的外壳。由此产生的重元素的分散使星际介质充满了必要的生命积木，否则这些积木会被锁在恒星的肚子里。 超新星残骸是一个充满团块的壳，看起来像一个红色皮肤的球体，里面充满了发光的种子，就像石榴一样。

皮肤是一个薄而明亮的外壳。 当一颗恒星爆炸时，喷出物slam进入周围气体并向外驱动冲击波。 大多数光线来自震波后面的薄层，因此一个大致球形的残留物投射到天空中，作为一个明亮的边缘，内部较暗，就像一个空心球体看起来像一个环一样。 那个边缘是石榴的外皮。

种子是团块状的喷出物。 爆炸星的内部不会冒出光滑的雾气。爆炸过程中的不稳定性会触发Rayleigh–Taylor手指（相同的过程，使密集的流体坐在较轻的流体上分裂成斑点） ，从而将喷射物分裂成密集的结。这些结富含新鲜制造的氧气、硫磺、硅和铁。当它们被反向冲击击中或遇到周围气体时，它们会单独点亮，呈现出明亮、紧凑的斑点。le ，距离11,000光年的超新星遗迹仙后座A ，显示成千上万的这些发光珠子散落在壳中。 这就是拱门。

残留物的窄带图像通常以氢-α和电离硫为主，两者都会发出红光，因此标准的假色选择使超新星残留物具有红宝石色调。 嵌在红色半透明的她身上的团簇ll类似于石榴的横截面。

从星际碎片中， CHNOPS元素找到了通往地球等宜居行星的道路。 值得注意的是，彗星和小行星都富含生命出现所必需的益生元有机分子。 NASA的OSIRIS-REx任务（来自小行星Bennu ）和JAXA的Hayabusa2 （来自星际）等任务返回的原始太空岩石样本iD Ryugu ）以及来自ESA的Rosetta等追逐彗星任务的数据，已经证实了CHNOPS基本元素的存在。罗塞塔号航天器直接在彗星67P的尘埃中检测到磷。Bennu和Ryugu都显示出氨基酸的存在，它们连接在一起形成蛋白质并驱动细胞结构和代谢功能。来自小行星Benn的样本揭示了30多种不同类型的氨基酸。这包括地球上生命使用的20种主要氨基酸中的15种（如甘氨酸、丙氨酸和缬氨酸）。美国宇航局的星尘任务在野生彗星2的尘埃中成功检测到简单的氨基酸甘氨酸，后来证实它漂浮在彗星67P周围的气体云中。所有五个典型核碱基：腺嘌呤（ A ）、鸟嘌呤（ G ）、Cytosine © ，胸腺嘧啶（ T ）和尿嘧啶（ U ） —在DNA和RNA中存储遗传密码的结构字母，原始保存在小行星Bennu和Ryugu内。在小行星材料中已鉴定出基本糖，如核糖（ RNA的中心框架）和葡萄糖（主要能量来源）。彗星和小行星含有挥发性化合物，如氨、甲醛、醛和KET那些。

这些发现有力地强化了外源递送理论，即数十亿年前小行星和彗星的猛烈宇宙轰击为早期地球播下了生命自发引发所需的水和原始有机库存的种子。

对星际物体3I/ATLAS的观测揭示了一种异常丰富的有机分子混合物，最值得注意的是甲醇（ CH OH ）、甲烷（ CH ）、氰化氢（ HCN ）和氰化物（ CN ） ，以及一氧化碳和水冰（如本文所述）的浓度下降到米深的层（如本文所述）。

所有这些观察都表明，生命的基石在整个银河系中无处不在。 由于类似的情况导致类似的结果，我们可能并不孤单e.

在寻找兄弟姐妹时，我们最好瞄准高而不是低，并考虑智能对手的可能性。 截至目前，天体生物学家计划投资超过100亿美元，在数千光年之外的系外行星大气中寻找微生物的化学指纹。 在他们这样做的同时，我们也应该投入相似的资金您正在研究靠近地球的不明异常现象（ UAP ） ，类似于在我们后院的岩石中寻找一个网球，以标记邻居的存在。 这是UAP科学咨询委员会（ https://uapsac.com/ ）正在做的事情，目前还没有资金。 人生最美好的事物是无价的。

人类最近用人工智能（ AI ）诞生了一个新物种。e与人工智能有着共同的祖先。 它的基本成分硅也被超新星喷射出来。

在这篇文章中，我展示了由著名艺术家格雷格·怀亚特（ Greg Wyatt ）创作并发送给我的系列作品中的八幅令人惊叹的美丽水彩画。

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原文链接：https://avi-loeb.medium.com/the-pomegra ... b29dce1428
作者：Avi Loeb（哈佛大学天文系教授）