A strange dark-matter phenomenon is speeding towards the Sun at speeds of 500 kilometers per second according to a 2018 study led by theoretical physicist Ciaran O’Hare from the University of Zaragoza in Spain. Billions of years ago, a dwarf galaxy was shred apart by the extreme tidal forces of our larger Milky Way Galaxy. The remnant galaxy now forms a stream, called S1, that arcs around the halo of our Galaxy. The stream is composed of tens of thousands of visible stars, and also up to a billion solar masses of invisible dark matter.
“I spent an hour just staring at this image,” lead researcher, astronomer Pieter van Dokkum of Yale University says as he recalls first seeing the Hubble image of NGC 1052-DF2, a galaxy completely void of dark matter. “This thing is astonishing, a gigantic blob so sparse that you see the galaxies behind it. It is literally a see-through galaxy. It’s so rare, particularly these days after so many years of Hubble, that you get an image of something and you say, ‘I’ve never seen that before.”
Can all life as we know it be traced back to the interstellar medium (ISM)? This March 2021, Michael McCarthy, an astrochemist and Acting Deputy Director of Harvard Center for Astrophysics (CfA), commented about the discovery of a vast, previously unknown reservoir of carbon as well as new molecules in a cold, dark molecular cloud in the interstellar medium for the first time “It makes you wonder,” he exclaimed, “what else is out there that we just haven’t looked for.”
“Hubble isn’t just a satellite; it’s about humanity’s quest for knowledge,” said astronaut and former NASA Chief Scientist, John M. Grunsfeld about the iconic space telescope. Looking at Hubble’s ground-breaking “Deep Field” images that show the most distant galaxies that can be observed in visible light leaves us feeling like something else is going about its business out there.
In 2019, the Hubble Space Telescope captured an image of one of the brightest known quasars in early universe, a luminous active galactic nucleus (AGN) shining with orders of magnitudes more luminosity than entire galaxies, powered at their hearts by all-consuming black holes shown above as it existed less than a billion years after the Big Bang. Its gargantuan black hole began devouring anything within its gravitational grasp, triggering a burst of star formation –a firestorm of energy equivalent to the light from 600 trillion Suns blazing across the universe.
The beauty and wonders of our planet’s night sky cloaks a violent, ever-changing universe of life, death, and mayhem –“with firestorms of star birth, dying stars rattling the very fabric of space in titanic explosions,” observes Hubble scientists. “Death-star-like beams of energy blasting out of overfed black holes at nearly the speed of light”, they say, “Hubble has seen them all.” A universe of which the Milky Way is one of 150 billion galaxies. A strange universe, hinted Stephen Hawking. “of shadow galaxies, shadow stars, and even shadow people.”
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