We Have Now Reached The Limits Of The Hubble Space Telescope
“Finally, there are the wavelength limits as well. Stars emits a wide variety of light, from the ultraviolet through the optical and into the infrared. It’s no coincidence that this is what Hubble was designed for: to look for light that’s of the same variety and wavelengths that we know stars emit.
But this, too, is fundamentally limiting. You see, as light travels through the Universe, the fabric of space itself is expanding. This causes the light, even if it’s emitted with intrinsically short wavelengths, to have its wavelength stretched by the expansion of space. By the time it arrives at our eyes, it’s redshifted by a particular factor that’s determined by the expansion rate of the Universe and the object’s distance from us.
Hubble’s wavelength range sets a fundamental limit to how far back we can see: to when the Universe is around 400 million years old, but no earlier.”
The Hubble Space Telescope, currently entering its 30th year of service, has literally revolutionized our view of the Universe. It’s shown us our faintest and most distant stars, galaxies, and galaxy clusters of all. But as far back as it’s taken us, and as spectacular as what it’s revealed, there is much, much more Universe out there, and Hubble is at its limit.
Here’s how far we’ve come, with a look to how much farther we could yet go. It’s up to us to build the tools to take us there.
What Was It Like When Mammals Evolved And Rose To Prominence?
“65 million years ago, 99.5% of the Universe’s history had already unfolded, and yet the ancestors of modern humans were no better developed than a modern-day lemur. Complex, differentiated animals had already existed for half-a-billion years, but it seems to be mere chance that led to the rise of an intelligent, technologically-advanced species like us. We do not yet know what secrets other planets hold as far as life goes, but here on Earth, the most remarkable story of all was just getting truly interesting.”
It was some 550-600 million years ago that life’s complexity exploded, at least in the fossil record, at the start of the Cambrian period. While that epoch marks
the first complex, differentiated, macroscopic, multicellular, sexually-reproducing animals arising and dominating the oceans, life would go on to develop traits that were absolutely necessary for eventually giving rise to human beings. Animals developed spinal cords, four limbs, moved onto land, became warm-blooded, and more. Most importantly, many such creatures were able to survive enormous extinction events, enabling them to rise to prominence when a previously-occupied niche opened up.
It took half a billion years from the Cambrian explosion for mammals to rise to prominence, but after the big K-T extinction event, we were the most adaptable organism left. Here’s the story of how mammals like us evolved and came to dominate the Earth.
Cosmology’s Only Big Problems Are Manufactured Misunderstandings
“We should always be aware of the limitations of and assumptions inherent to any scientific hypothesis we put forth. Every theory has a range of established validity, and a range where we extend our predictions past the known frontiers. A theory is only as good as the verifiable predictions it can make; pushing to new observational or experimental territory is where we must look if we ever hope to supersede our present understanding.
But we mustn’t forget or throw out the existing successes of General Relativity, the expanding Universe, the Big Bang, dark matter, dark energy, or inflation. Going beyond our current theories includes — as a mandatory requirement — encompassing and reproducing their triumphs. Until a robust alternative can reach that threshold, all pronouncements of “big problems” with the prevailing paradigm should be treated for what they are: ideologically-driven diatribes without the requisite scientific merit to back them up.”
It might seem like no fun to you: to look at all the imaginative alternative explanations to the mainstream scientific thought and declare them all to be insufficient. You might wonder where my imagination is, and what kind of lousy scientist I must be to deride all of these alternative ideas as obviously wrong, and to stick so closely to the prevailing orthodoxy. To an outsider, it might seem like I’m tremendously foolish. But to someone who understands what a scientific theory has to do, you’ll immediately recognize that there are thresholds one needs to surpass to bring about a scientific revolution, If you cannot meet those criteria, you don’t get to play in the same league.
Some people might claim that cosmology has some big problems, but that’s not what you see if you make an honest and accurate assessment. Get the truth, rather than the hype, today.
Today Marks The Anniversary Of Neil Armstrong’s Near-Fatal Lunar Landing Vehicle Crash
“Softly landing on the Moon, with no horizontal motion and only slight vertical motions, was a tremendous problem facing NASA. There was no computerized guidance or high-resolution maps of the lunar landing site. The eventual lunar module pilot would have to navigate the touchdown manually. Armstrong was training in Lunar Landing Research Vehicle #1 on May 6, 1968, when something went horribly awry.”
A year prior to the Apollo 11 Moon landing, Neil Armstrong was undergoing his 22nd test flight in the Lunar Landing Research Vehicle, the test vehicle for NASA’s Lunar Module. Designed to simulate lunar gravity here on Earth, with vertical takeoff and landing capabilities, it was the ultimate way to train for one of the most essential parts of the mission: landing on the Moon.
But 51 years ago today, something went horribly wrong. Engineers would later determine that a problem with helium pressure, causing the hydrogen peroxide on board to become depleted and leading to a fuel imbalance and the eventual failure of the reserve attitude thrusters. From a height of approximately 200 feet and with no warning, Armstrong ejected.
Five seconds later, the vehicle was a flaming wreck on the ground. Come get the story behind one of the great escapes in NASA history!
Ask Ethan: How Does The Event Horizon Telescope Act Like One Giant Mirror?
“I’m having difficulty understanding why the EHT array is considered as ONE telescope (which has the diameter of the earth).
When you consider the EHT as ONE radio telescope, I do understand that the angular resolution is very high due to the wavelength of the incoming signal and earth’s diameter. I also understand that time syncing is critical.
But it would help very much to explain why the diameter of the EHT is considered as ONE telescope, considering there are about 10 individual telescopes in the array.”
Humanity has imaged a black hole’s event horizon! It’s been less than a month since the news was announced, and it’s still hard to get over what a phenomenal achievement it was. It’s very difficult to conceive of how, though, we can treat 8 different telescopes and telescope arrays, all stitched together, as acting like a single giant mirror. But that’s exactly what the Event Horizon Telescope did. In fact, that’s what it needed to do, or it would never have been able to achieve the resolutions necessary to construct the first image of a black hole’s event horizon.
But we have it! We achieved it! And here’s the conceptual way you can understand it, even if you barely understand the way a single telescope works.
Starts With A Bang #44 – The Expanding Universe
One of the biggest conundrums in the Universe surrounds the question of how quickly the Universe is expanding. Questions like what is the Universe made of, how old is it, what is it’s ultimate fate, etc., absolutely depend on this. For generations, we argued over the details of this, seeming to have finally reached a consensus in 2001 with the Hubble Key Project’s results: 72 km/s/Mpc, with an uncertainty of about 10%. But the modern results, as of 2019, seem to depend on how you measure it. Some teams are consistently getting 67 km/s/Mpc, while others get 73-74 km/s/Mpc, with uncertainties that don’t overlap.
This may not be a controversy, but rather a clue, and Nobel Prizewinner and co-discoverer of dark energy Adam Riess joins me on this special edition of the Starts With A Bang podcast. Don’t miss it!
(Image credit: NASA / GSFC)
Cosmology’s Biggest Conundrum Is A Clue, Not A Controversy
“This is not some fringe idea, where a few contrarian scientists are overemphasizing a small difference in the data. If both groups are correct — and no one can find a flaw in what either one has done — it might be the first clue we have in taking our next great leap in understanding the Universe. Nobel Laureate Adam Riess, perhaps the most prominent figure presently researching the cosmic distance ladder, was kind enough to record a podcast with me, discussing exactly what all of this might mean for the future of cosmology.
It’s possible that somewhere along the way, we have made a mistake somewhere. It’s possible that when we identify it, everything will fall into place just as it should, and there won’t be a controversy or a conundrum any longer. But it’s also possible that the mistake lies in our assumptions about the simplicity of the Universe, and that this discrepancy will pave the way to a deeper understanding of our fundamental cosmic truths.”
In science, if you want to know some property of the Universe, you need to devise a measurement or set of measurements you can make to reveal the quantitative answer. When it comes to the expanding Universe, we have many different methods of measuring light that fall into two independent classes: using the imprint of an early relic and using the cosmic distance ladder. These two techniques each give solid results that are mutually inconsistent: the distance ladder teams find results that are higher than the early relic teams by about 9%. Since the errors are only about 1-2% on each measurements, this has been dubbed cosmology’s biggest controversy.
But perhaps it’s not about “who is right,” but rather about “what is the Universe doing?” Perhaps it’s a clue, not a controversy. Come learn about the cutting-edge science behind this fascinating and unexpected result.
This Is Why Every Parent Should Fully Vaccinate Their Children
“It’s one of the most important decisions you’ll ever make in your life: do I vaccinate my child, and do I do it according to the CDC’s recommended timetable? There’s a lot of information out there from groups that both encourage and discourage vaccination. While some of what’s out there is downright false, it truly is a complex issue.
On one hand, vaccines are truly a marvelous defense against a wide variety of infectious diseases. Afflictions that would sicken, injure, blind, paralyze, or even kill millions of children a year worldwide could be — and in some cases, have been — effectively eradicated in humans. On the other hand, no vaccine can be 100% safe or effective, and many parents have nightmare stories about what happened to their child almost immediately after having a vaccine administered. This is what every parent should know.”
There are a lot of voices out there talking about vaccine safety, disease, illness, and injury, and it seems like very few of them are listening to each other. On the one hand, vaccines are literally the greatest public health advance humanity has ever made, saving thousands to millions of lives annually by preventing otherwise lethal diseases. On the other hand, though, there are many stories of parents who vaccinated their children, only to see them experience a series of catastrophic symptoms afterwards.
We all need to express compassion and show empathy towards one another, otherwise understanding will be impossible. Once you know all the facts, I think you’ll agree: vaccination is unequivocally the way to go.
What Was It Like When Life’s Complexity Exploded?
“It is no doubt an oversimplification to state that horizontal gene transfer, the development of eukaryotes, multicellularity, and sexual reproduction are all it takes to go from primitive life to complex, differentiated life dominating a world. We know that this happened here on Earth, but we do not know what its likelihood was, or whether the billions of years it needed on Earth are typical or far more rapid than average.
What we do know is that life existed on Earth for nearly four billion years before the Cambrian explosion, which heralds the rise of complex animals. The story of early life on Earth is the story of most life on Earth, with only the last 550-600 million years showcasing the world as we’re familiar with it. After a 13.2 billion year cosmic journey, we were finally ready to enter the era of complex, differentiated, and possibly intelligent life.”
For the first few billion years of planet Earth, our world indeed had life occupying practically every niche we could imagine, but it was vastly different from the life we recognize today. Rather than complex, differentiated, multicellular organisms, all life in the early stages was single-celled and simple. Seemingly all at once, life’s complexity exploded some 550-600 million years ago during the Cambrian era. But this was no miraculous single event, but rather the culmination of many steps that worked together, in tandem, to make it all possible.
It took 13.2 billion years of cosmic evolution to give rise to the first megaflora and megafauna we find on Earth. Here were the critical steps that got us there.
Fantasy Genetics Is The Most Important, And Worst, Science In Game Of Thrones
“All of this sets up a world where the most genetically pure members of the most powerful race — the Targaryens — have a righteous claim to rule the seven kingdoms. But this is a white supremacist’s ideal view of genetics, not a lesson in how genetics actually works.
In reality, race is not a biologically meaningful category.
In reality, genetic diversity increases biological fitness among humans, rather than diluting it.
In reality, inbreeding poses a dizzying array of potential inherited disorders, including: blindness, hearing loss, schizophrenia, decreased fertility, immune disorders, Grave’s disease (prevalent in Ptolemaic Egypt), and lantern jaw (which disproportionately afflicted the inbreeding-rich Habsburg house in Europe).”
Who is the rightful heir to the iron throne, and who is best suited to take on that role? Perhaps, contrary to what we might think from watching the show, successfully inbreeding your way to hold onto power isn’t a long-term strategy for anything except extinction. Real genetics works very differently from the fantasy genetics of Game of Thrones, and we should all learn why this is the case.
The Lannisters and Targaryens might have issues with inbreeding, but it’s nothing compared to House Frey. Come see the real consequences and get the science behind the genetics of Game of Thrones!