The process of Becoming

Published on by Catherine Toulsaly

Imagination is a Monastery and I am its Monk

John Keats

 

I have found inspiration in myths and folktales. According to a legend, so “many moons ago” Native American tribes lived underground in total darkness. One of their animals, a ground mole, one day crawled through a hole and saw trees and rivers and the sky! The mole crawled back through the hole as fast as it could and told everyone of the wonders it had seen. Sadly, the light had made it blind. And so everyone climbed through that hole into the wonders of the Earth. 

 

Since I wrote about Ultima Thule over a year ago, the Kuiper Belt object was renamed Arrokoth, a term meaning “sky” in the Powhatan/Algonquian language as if we became the explorers who have sailed off across space and reached the last frontier of the Solar system to gaze at the skyline. The snowman-shaped 21-miles long planetesimal is thought to have formed in place and remained largely undisturbed. Once believed to be composed of two distinct spherical objects, it was shown during the New Horizons flyby last year that it is, in fact, a contact binary made of two lobes formed separately in a collapsing pebble cloud of the protosolar nebula at the time of planetesimal formation until the accretion of the two parts took place over 4 billion years ago

 

Arrokoth reminds me of another Native American tale, this one of Elegant who collected all the rags that he could find, and, kneading snow over a framework of animals' bones, molded it into the shape of a man. The formation process of the geometric, co-joined object appears to be common in the Kuiper belt, based on the abundance of binaries detected there in telescopic surveys. I can’t help but wonder whether Arrokoth is on its way to becoming a passing comet.

 

 

A team of researchers has studied three very different objects of the Solar system: Arrokoth, Saturn's captured moon, Phoebe and Pluton in order to uncover any footprints of their interstellar inheritance and shed light on the composition of the early solar nebula. Another planetary nebula, Helix Nebula (NGC 7293), shows the presence, inside its molecular envelope, of microstructures, those dense clumps of gas and dust known as cometary knots which might have happened after photoionization of the nebula.

Helix Nebula (NASA/JPL-Caltech/Univ.of Ariz.)

Helix Nebula (NASA/JPL-Caltech/Univ.of Ariz.)

 

What I see in nebulae is a sense of becoming. In the Ode on the Grecian Urn, the Urn whispered in the poet’s ear that beauty is truth, truth is beauty. Nebulae with gargantuan clouds colliding and burrowing into each other are celestial beauties, striking forms under a veil, entangled gas filaments, ghosts with an ethereal soul. If a collision takes place head-on between two clouds of different sizes, a cavity forms in the larger one through this process, and the larger cloud appears as a ring-like structure on the plane of the sky.

There are many different types of nebulae. We are told that four billion years ago, our place in space resembled the Orion nebula which,  together with its associated Orion Nebula Cluster located within the Orion A molecular cloud, is the closest region of star formation that involves massive stars. The brightest part of the nebula, the Huygens Region, in the northeast corner of the Extended Orion Nebula, comprises the Orion Nebula Cluster and is named after the Dutch astronomer Christiaan Huygens who, in 1659, made a drawing for the first time of the Orion Nebula in his work Systema Saturnium. The densest region in the core of the Orion Nebula Cluster corresponds to the Trapezium cluster, where massive young stars excite and illuminate the nebula

 

Researchers are hoping to figure out at what evolutionary stage nursery stars are. Some are still accreting matter as if they were hiding in a cocoon, larvae in a beehive. For others, the presence of a transitioning disk gives an early clue on the development of future planets. A paper published last month presented an extensive study on protoplanetary Disks in the Orion Nebula Cluster. Another studied the accretion activity in young stellar objects in the Cluster and detected the presence of young transition disks with ages between 1 and 3.5 million years. And yet another paper published in January highlighted the structure of the Orion Nebula and its Interaction with Orion-S.


Interstellar dust plays an essential role within the interstellar medium through a myriad of microphysical processes. In the Horsehead nebula, the dominant process is the exposure of dust grains from the dense molecular cloud to the UV light of the multi-star system Sigma Ori. With dust evolution models, researchers are given the means to study how dust grains fragmentate, coagulate and transform under the thermal processes and UV light of stars depending on the wide range of interstellar medium physical conditions from the formation of icy mantles to the transfer of energy in the form of electromagnetic radiation when heated by photons. 

Carina Nebula (NASA/ESA/STScI)

Carina Nebula (NASA/ESA/STScI)

The Carina Nebula Complex is one of the most active massive-star-forming regions in the Milky Way with approximately 140 massive OB-stars and more than 1400 young stellar objects. In a paper published in March,  it was proposed a scenario wherein the formation of massive stars in the clusters was triggered by a collision between two clouds about one million years ago. Zeta Opiuchi was the subject of another 2020 study aimed at learning more about the nature of dust and magnetic fields in stellar bowshock nebulae, which form at the interface between the interstellar medium and the stellar wind from massive runaway host stars. Another recent paper identified new young stellar objects in the Lagoon Nebula while the Bubble Nebula was reported to be composed of a series of nested shells, some showing blister-like structures.

Lagoon Nebula (NASA, ESA, STScI)

Lagoon Nebula (NASA, ESA, STScI)

The Blue Ring Nebula is a different kind of nebula, the only ultraviolet-emitting nebula discovered to date. A newly released paper explained this relic of an ancient star-companion collision while another reported about the Gum Nebula, home to at least 32 cometary globules, the so-called comet-like clouds. Yet, another kind of nebula is the Pulsar wind nebula with a toroidal magnetic field structure. It is generally believed to be a site generating high energy galactic cosmic rays, like the Crab Nebula.

 

Chandra-crab

The Universe is in a state of becoming. Could an observer, convinced that the “sense” of the Universe must lie beyond, crawl outside and come back with the tale of the zygote constrained within the walls of a transparent membrane? If space-time is the record of physical reality, it is only one aspect of reality in the infinite game of space, time and gravity, in which recurrence of similar events alternate with thresholds of new unknown. There are “no spatial or numerical boundaries to an infinite game”, wrote James P. Carse, “No world is marked with the barriers of infinite play”. 

 

 

Anak Krakatau erupted two days ago like it has been periodically since it emerged above sea level in 1927 near the site of the great eruption of Krakatau in 1883. History, wrote Sydney J. Harris. "repeats itself, but in such cunning disguise that we never detect the resemblance until the damage is done". Another oak tree has died as I seek comfort in the sky. At least the half-feral cat ran away from under our house where Carolina wrens have taken refuge again.

Anak Krakatau (James D. P. Moore/Earth Observatory of Singapore)

Anak Krakatau (James D. P. Moore/Earth Observatory of Singapore)

 

In the Earth’s outer layer, I see carved human-like figures running toward the source of time and dragon-shaped forms emerging from silvery stagnant waters. But the Moon caught me in my sleep. Her brightness woke me up from my slumber. The next morning, I wonder where she has gone, buried in the clouds as she waits for the strong winds of Spring.

Rio Geba in Guinea-Bissau ( pictured from the International Space Station)

Rio Geba in Guinea-Bissau ( pictured from the International Space Station)

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