“Perhaps,” Harvard astrophysicist Avi Loeb told The Daily Galaxy: “We developed our modern science and technology (including transit astronomy and radio communication capabilities) only over a century out of the 4.5 billion years of the Earth’s lifetime. The window of opportunity for anyone to notice us at a random time in Earth’s history is roughly one part in 45 million (4.5 billion divided by 100 years).
Your free twice-weekly fix of stories of space and science –a random journey from Planet Earth through the Cosmos– that has the capacity to provide clues to our existence and add a much needed cosmic perspective in our Anthropocene epoch.
“The interesting thing is: we have no idea!” says Pieter van Dokkum, Sol Goldman Professor of Astronomy at Yale University, who wrote in an email to The Daily Galaxy about why ultra-diffuse galaxy DF2 contains no dark matter. “The existence of this galaxy shows that there is another pathway to creating galaxies than our standard picture, but what that might be is anyone’s guess.”
“We’ve taken a major step back in time, beyond what we’d ever expected to be able to do with Hubble. We see GN-z11 at a time when the universe was only three percent of its current age,” observed Pascal Oesch at the University of Geneva and head of the Galaxy Build-Up at Cosmic Dawn team about the discovery of a 13.4 billion-years -old galaxy. It’s mind-boggling by comparison to think that Earth is only 4.5 billion years old.
What will we actually see? When it’s completed, the picture of the Milky Way’s supermassive black hole, Sagittarius A* (Sgr A*), is an image sure to equal the famous “Earthrise” photo taken by Apollo 8 astronaut Bill Anders in December 1968. The obvious target for the Event Horizon Telescope (EHT), the team hopes to get imagery of our supermassive black hole soon, said Shep Doeleman, Director, Event Horizon Telescope, following the first ever image of Galaxy M87’s gargantuan black hole (above).
“Reheating was an insane time, when everything went haywire,” says David Kaiser, the Germeshausen Professor of the History of Science and professor of physics at MIT. As the Big Bang theory goes, reports MIT, somewhere around 13.8 billion years ago the universe exploded into being, as an infinitely small, compact fireball of matter that cooled as it expanded, triggering reactions that cooked up the first stars and galaxies, and all the forms of matter that we see (and are) today.