Scholars have wondered how mammals emerged as the dominant class of animals following the cataclysmic impact of an asteroid on Earth that wiped out the dinosaurs.
Previous theories suggested that the animals lived in the shadows of the giant lizards until the asteroid hit the planet around 66 million years ago.
But a new study has found that mammals were constantly evolving and adapting before the impact which allowed them to weather the mass extinction event, New Scientist reported.
Researcher Jorge García-Girón and his team studied more than 1,600 fossils of different North American fauna, including dinosaurs, fish, reptiles, amphibians and mammals. They created an estimation of the niches each extinct species occupied and entered the data into a computational model developed to track how food webs change over time.
Their findings showed that dinosaurs living 66 million years ago in North America closely resembled their ancestors 18 million years earlier, which represented a form of ecological stability.
But the mammals were playing the evolution card: Despite living among larger dinosaurs, they continuously adapted and evolved into a vast array of creatures able to climb, glide, and swim among other features during this period.
“It not only amazed me how mammals managed to thrive in the highly complex, and probably dangerous, dinosaur-dominated ecosystems,” said García-Girón, but also how rapidly our ancestors moved into vacant niches after the asteroid hit, he added.
Contrary to past studies, the researchers also found dinosaur numbers were not declining prior to the impact.
Maybe our mammal ancestors were just waiting for the right time to rule the planet.
Best of the season and for the New Year. Thanks for the card. I was struck by it saying humans on Mars. Right now we can’t even get humans from one city to the next in these storms. Welcome to Global Warming. Yes seems strange but not really. Cold air normally trapped in the North because of warming now escapes and goes south and lambasts us in huge snow storms and bizarre temperature changes including freezing weather.
David
Jack Waldbewohner <ohomen171@gmail.com>
4:28 PM (3 minutes ago)
to David, bcc: Elena, bcc: Artemis, bcc: Barbara, bcc: Marianna, bcc: Chris
Dear David:
It is ironic. Some of these jurisdictions hit -39F with wind chill (Des Moines). That kind of wild cold plays hell with power grids. Texas is worst of all. The Republican fascists took control of the power grid and did disastrous deregulation. In a big storm a couple of years ago hundreds of people died in Texas. The Republican fascists swore that they improved the grid. Already some outer fringes are failing in this cold. My smart Texas friends have done what I did here in Pacifica. They have bought natural gas-powered Generac generators that kick in when the grid fails. Natural gas keeps going when the power grid goes down. You have your experiences with cold in Canada. Before the money got bad, I hung out a lot in Bariloche in Patagonia. In the dead of winter temperatures can drop to -25 F. Locals tell me that natural gas never fails.
Darwin is misquoted as saying it is “The survival of the fittest.” I think that he meant that is: “The survival of the most adaptable.”
Do not worry about rockets to Mars. They have launch sites not getting hit by frigid temperatures that often.
ExploreMars.Org Committed to Human Exploration of Mars by the 2030s
IMAGE CREDIT: SpaceX
Dr. Sian “Leo” Proctor to serve as ExploreMars.Org Astronaut Ambassador
Explore Mars, Inc is pleased to announce that Dr. Sian Proctor will now serve as the Explore Mars Astronaut Ambassador. According to Dr. Proctor, “ I look forward to taking on the new role of the Explore Mars Astronaut Ambassador. This new role will enable me to carry out my mission of using space to inspire while also championing the Explore Mars mission. Together, we aim to create a future space that is accessible, just, equitable, diverse, and inclusive for all of humanity, both on Earth and beyond.”
Dr. Sian “Leo” Proctor, SpaceX’s Inspiration4 pilot unfurls the ExploreMars.Org flag she flew to space on the Inspiration 4 mission, the first civilian flight into space
Last week, NASA announced that astronomers, using spectroscopic data from the James Webb Space Telescope, had confirmed that some early galaxies the telescope had detected dated back to just 350 million years after the Big Bang. That makes the galaxies the oldest detected to date as astronomers seek to push back the curtain shrouding the early universe.
While the discovery—still going through the peer-review process, NASA advised—is a major step in astronomy, it still offers few insights about the Big Bang itself. That includes what happened in the earliest instants after the Big Bang, critical to the later formation of stars, galaxies, and broader structure in the universe, but also why the universe itself exists in the first place, and why it seems, to some, to be particularly “fine-tuned” for life.
“The spontaneous formation of a brain in empty space stands a much better chance (statistically) of occurring than the creation of our universe through cosmic inflation,” she writes.
Those are questions that Laura Mersini-Houghton, a theoretical physicist and cosmologist at the University of North Carolina, has been studying throughout her career. In Before The Big Bang, she discusses one potential solution to those questions, a topic she pioneered and is now gaining traction in the broader physics field: that out universe is part of a much larger multiverse.
Mersini-Houghton was motivated to pursue this topic because of a sticking point in the widely accepted model of cosmic inflation. While inflation explains the initial expansion of the universe after the Big Bang, “the infant universe must have been a remarkably unusual state of exceptional order” for it to turn out in this way, she writes. How unusual? “The spontaneous formation of a brain in empty space stands a much better chance (statistically) of occurring than the creation of our universe through cosmic inflation.”
That seems like a problem to her, so she studied it for much of her career, even though the issue was at the outskirts of mainstream thought in cosmology and astrophysics. The solution that she and a few colleagues developed involved string theory, specially something called the string-theory landscape. That provides, she writes, “a vast collection of initial energies—of potential Big Bang energies—capable of jump-starting multiple universes.”
That led them down the path of the multiverse concept, including the realization that our particular set of initial conditions is actually favored: “there is absolutely nothing special or exclusive about our beginning.” That model does have some testable hypotheses, such as features in the cosmic microwave background that could be created by entanglement with other universes immediately after the Big Bang. The concept of a multiverse now has much broader acceptance, she notes, something that occurred even during the process of writing the book.
The concepts in Before The Big Bang can be difficult to grasp at times, from quantum entanglement to 11-dimension string theory (that’s true “even for seasoned physicists,” she notes.) She avoids equations and mathematics to make it a little less challenging. She also weaves in anecdotes from her life, particularly growing up in Albania when the country was a repressive, isolated Communist regime, which shaped her career (“in light of my childhood experiences in Albania, the decision to research the creation of the universe didn’t feel like a particularly courageous act,” she writes of her decision to pursue that particular field.) The book is an enlightening read about the formation of our universe and the mysteries that still remain about how we got here.
Jeff Foust (jeff@thespacereview.com) is the editor and publisher of The Space Review, and a senior staff writer with SpaceNews. He also operates the Spacetoday.net web site. Views and opinions expressed in this article are those of the author alone.
The “Blue Marble” image from Apollo 17 is one of the most iconic images in history. (credit: NASA)
The first photograph of the entire globe: 50 years on, Blue Marble still inspires
by Chari Larsson Monday, December 12, 2022
December 7 marked the 50th anniversary of the Blue Marble photograph. The crew of NASA’s Apollo 17 spacecraft—the last human mission to the Moon—took a photograph of Earth and changed the way we visualized our planet forever.
By removing the graticule—the grid of meridians and parallels humans place over the globe—the image represented an Earth freed from mapping practices that had been in place for hundreds of years.
Taken with a Hasselblad film camera, it was the first photograph taken of the whole round Earth and is believed to be the most reproduced image of all time. Up until this point, our view of ourselves had been disconnected and fragmented: there was no way to visualize the planet in its entirety.
The Apollo 17 crew were on their way to the moon when the photograph was captured 29,000 kilometers from the Earth. It quickly became a symbol of harmony and unity.
The previous Apollo missions had taken photographs of the Earth in part shadow. Earthrise shows a partial Earth, rising up from the Moon’s surface.
In Blue Marble, the Earth appears in the center of the frame, floating in space. It is possible to clearly see the African continent, as well as Antarctica’s south polar ice cap.
Photographs like Blue Marble are quite hard to capture. To see the Earth as a full globe floating in space, lighting needs to be calculated carefully. The sun needs to be directly behind you. Astronaut Scott Kelly observes that this can be difficult to plan for when orbiting at high speeds.
Produced against a broader cultural and political context of the “space race” between the United States and the Soviet Union, the photograph revealed an unexpectedly neutral view of Earth with no borders.
Disruption to mapping conventions
According to geographer Denis Cosgrove, the Blue Marble disrupted Western conventions for mapping and cartography. By removing the graticule—the grid of meridians and parallels humans place over the globe—the image represented an Earth freed from mapping practices that had been in place for hundreds of years.
The photograph also gave Africa a central position in the representation of the world, whereas Eurocentric mapping practice had tended to reduce Africa’s scale.
The image quickly became a symbol of harmony and unity. Instead of offering proof of America’s supremacy, the photograph fostered a sense of global interconnectedness.
Since the Enlightenment, mapping and map making had emphasized man’s superiority over the Earth. Working against this hierarchy, Blue Marble evoked a sense of humility. Earth appeared extremely fragile and in need of protection. In his book Earthrise, Robert Poole wrote: “Although no one found the words to say so at the time, the ‘Blue marble’ was a photographic manifesto for global justice.”
The “2002 Blue Marble” was a composite based on images from Earth science satellites. (credit: NASA/Robert Simmon and Reto Stöckli)
Blue Marble’s afterlives
It is impossible to examine Blue Marble and separate it from the urgency of today’s climate crisis.
It quickly became a symbol of the early environmental movement, and was adopted by activist groups such as Friends of the Earth and annual events such as Earth Day.The photograph appeared on the cover of James Lovelock’s book Gaia (1979), postage stamps, and an early opening sequence of Al Gore’s An Inconvenient Truth (2006).
Advances in technology might help explain the photograph’s enduring charm from the vantage point of 2022. The first photograph of our planet was remarkably lo-fi.
The ways we have viewed and visualized Earth have changed over the decades. Starting in the 1990s, NASA created digitally manipulated whole-Earth images titled Blue Marble: Next Generation, in honor of the original Apollo 17 mission. These are composite images composed of data stitched together from thousands of images taken at different times by satellites.
Space-based imaging technology has continued to advance in its capacity to render astonishing detail. Art historians such as Elizabeth A. Kessler have linked these new generation of images picturing the cosmos with the philosophical concept of the sublime.
The photographs create a sense of vastness and awe that can leave the spectator overwhelmed, akin to 19th century Romantic paintings such as Thomas Moran’s The Grand Canyon of the Yellowstone (1872).
These advances in technology might help explain the photograph’s enduring charm from the vantage point of 2022. The first photograph of our planet was remarkably lo-fi. Blue Marble is the last full Earth photograph taken by an actual human using analogue film: developed in a darkroom when the crew returned to Earth.
Launching with cost-plus, landing with fixed-price: the financial underpinnings of a lunar return
by Tarak Makecha Monday, December 12, 2022
NASA’s attempt to return to its ambitious traditions and establish a long-term presence on the Moon kicked off on November 16 with the launch of the Space Launch System (SLS). That launch was the first step in NASA’s Artemis program that should ultimately set the stage for a human mission to Mars. It is not off to a good start.
“We saw that the cost-plus contracts that NASA had been using to develop the combined SLS and Orion system worked to the contractor’s rather than NASA’s advantage.”
It has taken 11 years from the start of the SLS development in 2011 to get the rocket to just lift off, six years behind schedule at an estimated $4.1 billion per launch—more than double its target. Paul Martin, NASA’s inspector general, called that cost “unsustainable.” Part of the blame can be attributed to cost-plus contracts, which NASA administrator Bill Nelson called a “plague” and the biggest threat to NASA’s goal of landing humans on the Moon by 2025.
In a cost-plus contract, the government pays a company the development costs plus a percentage fee, creating a perverse incentive. How? The longer the development, the higher the cost. The higher the cost, the greater the fees the company takes home. Which is why Martin told Congress, “We saw that the cost-plus contracts that NASA had been using to develop the combined SLS and Orion system worked to the contractor’s rather than NASA’s advantage.”
Fortunately, an alternative to cost-plus exists that reduces costs: competitive and milestone based fixed-price contracts. A fixed-price contract sets a price that is not subject to adjustment. This means the company picks up the bill for cost overruns rather than NASA. There is evidence to support its efficacy: according to a study by The Aerospace Corporation, fixed-price contracts experience 16% less cost growth than contracts using cost-plus.
One way fixed-price contracts contain costs is by incentivizing collaboration. If a company identifies requirements that are unnecessary and can convince NASA, they are removed. This saves the company money, and both the company and NASA time. This collaborative incentive does not exist in a cost-plus contract: more requirements leads to more cost which leads to higher fees for the company. As Elon Musk, CEO of SpaceX, notes, “The government will come up with some set of requirements, and 90% of them could make a lot of sense, and 10% are cockamamie that double the price of the project. But those 10% of cockamamie requirements in a cost-plus contract? The contractor will always say yes.”
Fixed-price contracts can also contain costs by being coupled with milestones and multiple vendors. Paying a company when they achieve a milestone, like a flight test, puts the focus on results. And the knowledge that there is another company working towards the same goal creates competition, leading to savings between 15 and 50%.
There is, however, a time and place for cost-plus contracts. A project that requires developing new technology brings less predictability in cost and timeline. This uncertainty means a company is less likely to bid with a fixed price contract. However, SLS is not new technology: it uses components from the Space Shuttle that first flew in 1981. And companies have been developing rockets independent of US government programs, leading the US Air Force to transition from cost-plus to fixed-price contracts for launching satellites. Why then does SLS use cost-plus contracts? Politics.
Despite the cost-plus headwinds, there is reason to be optimistic. SLS is key to the Artemis program, but it isn’t the only show in town.
Despite the cost-plus headwinds, there is reason to be optimistic. SLS is key to the Artemis program, but it isn’t the only show in town. The SLS will transport astronauts from earth to lunar orbit, but the task of taking astronauts from lunar orbit to the moon will be the job of the Human Landing System (HLS). The HLS was awarded to SpaceX using a milestone-based fixed-price contract. And NASA plans to award a second contract to develop another HLS from a company other than SpaceX, creating competition.
If HLS outperforms SLS in cost and schedule, it will add pressure on Congress to shift away from cost-plus and towards fixed-price contracts. A move that will help NASA catch up from Artemis’ poor start.
Tarak Makecha is a former US Army Ranger and current aerospace and defense industry executive with experience spanning large prime contractors, Tesla, and startups. This experience provides him with a unique perspective on the relationship between the government and commercial development of advanced technology. He was born and raised a few minutes away from NASA’s Johnson Space Center and one of his first jobs was at Space Center Houston.
The “Blue Marble” image from Apollo 17 is one of the most iconic images in history. (credit: NASA)
The “2002 Blue Marble” was a composite based on images from Earth science satellites. (credit: NASA/Robert Simmon and Reto Stöckli)
jacksmars 