I hope you will enjoy this Halloween special. Today, we are trying something a little bit different by exploring the evolution of a particular animal : Bats.
While their evolutionary history is shrouded in mystery, they allow us, nonetheless, to explore 2 interesting ideas :
1- Convergent evolution : How organisms tend to evolve similar (albeit not identical) body plans as solutions to similar problems (flight in birds, bats and pterosaurs)
2- Prediction : Like any theory, evolution is not only descriptive, but also predictive. Thanks to its models and principles, it allows us to make predictions to complement our gap in observational data.
Happy Halloween!
P.S. : The blog in the third picture is neither scientific nor peer-reviewed. But it is a nice illustration of how the common ancestor of bats MIGHT have looked like, and how using basic principles from evolution, phylogeny, and comparative anatomy, we can visualize how some animals have come to be what they are.
NASA astronauts Shannon Walker, Victor Glover, and Mike Hopkins, and JAXA (Japan Aerospace Exploration Agency) astronaut Soichi Noguchi embark on a historic mission on November 14, 2020 aboard the Crew Dragon. NASA’s Crew-1 mission marks the first certified crew rotation flight to the International Space Station. During their 6-month stay on orbit, these crew members will don their science caps and complete experiments in microgravity. Check out five out of this world experiments you can expect to see these space scientists working on during Expedition 64.
The Crew-1 astronauts will become space farmers with the responsibility of tending to the rad(ish) garden located in a facility known as the Advanced Plant Habitat (APH). Researchers are investigating radishes in the Plant Habitat-02 experiment as a candidate crop for spaceflight applications to supplement food sources for astronauts. Radishes have the benefits of high nutritional content and quick growth rates, making these veggies an intriguing option for future space farmers on longer missions to the Moon or Mars.
Microbes can seemingly do it all, including digging up the dirt (so to speak). The BioAsteroid investigation looks at the ability of bacteria to break down rock. Future space explorers could use this process for extracting elements from planetary surfaces and refining regolith, the type of soil found on the moon, into usable compounds. To sum it up, these microbial miners rock.
The iconic spacesuits used to walk on the moon and perform spacewalks on orbit are getting an upgrade. The next generation spacesuit, the Exploration Extravehicular Mobility Unit (xEMU), will be even cooler than before, both in looks and in terms of ability to regulate astronaut body temperature. The Spacesuit Evaporation Rejection Flight Experiment (SERFE) experiment is a technology demonstration being performed on station to look at the efficiency of multiple components in the xEMU responsible for thermal regulation, evaporation processes, and preventing corrosion of the spacesuits.
Crew-1 can expect to get a delivery of many types of chips during their mission. We aren’t referring to the chips you would find in your pantry. Rather, Tissue Chips in Space is an initiative sponsored by the National Institutes of Health to study 3D organ-like constructs on a small, compact devices in microgravity. Organ on a chip technology allows for the study of disease processes and potential therapeutics in a rapid manner. During Expedition 64, investigations utilizing organ on a chip technology will include studies on muscle loss, lung function, and the blood brain barrier – all on devices the size of a USB flashdrive.
Circadian rhythm, otherwise known as our “internal clock,” dictates our sleep-wake cycles and influences cognition. Fruit flies are hitching a ride to the space station as the subjects of the Genes in Space-7 experiment, created by a team of high school students. These flies, more formally known as the Drosophila melanogaster, are a model organism, meaning that they are common subjects of scientific study. Understanding changes in the genetic material that influences circadian rhythm in microgravity can shed light on processes relevant to an astronaut’s brain function.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
For updates on other platforms, follow @ISS_Research, Space Station Research and Technology News, or our Facebook to keep up with the science happening aboard your orbiting laboratory, and step outside to see the space station passing over your town using Spot the Station.
Women who had ADHD (24%) [were more likely to have attempted suicide] compared to women who had not (3%).
Men with ADHD were also more likely to have attempted suicide compared to men without ADHD (9% vs. 2%).
Adults with ADHD were much more likely to have attempted suicide than those without (14.0% vs. 2.7%).
(Study in full)
On June 24, 2020, NASA announced the agency’s headquarters building in Washington, D.C., was to be named after Mary W. Jackson, the first African American female engineer at NASA.
Jackson’s story — along with those of her colleagues Katherine Johnson, Dorothy Vaughan, and Christine Darden — was popularized with the release of the “Hidden Figures” movie, based on Margot Lee Shetterly’s book by the same name.
Today, as the accomplishments of these women are brought to light, we celebrate them as Modern Figures — hidden no longer. Despite their recent recognition, we cannot forget the challenges that women and BIPOC faced and continue to face in the STEM fields.
Jackson showed talent for math and science at an early age. She was born in 1921 in Hampton, Virginia, and attended the all-Black George P. Phenix Training School where she graduated with honors. She graduated from Hampton Institute (now Hampton University) in 1942 with a bachelor of science degree in both mathematics and physical sciences.
Jackson worked several jobs before arriving at the National Advisory Committee on Aeronautics (NACA), the precursor organization to NASA. She was a teacher, a receptionist, and a bookkeeper — in addition to becoming a mother — before accepting a position with the NACA Langley Aeronautical Laboratory’s segregated West Area Computers in 1951, where her supervisor was Dorothy Vaughan.
After two years in West Computing, Jackson was offered a computing position to work in the 4-foot by 4-foot Supersonic Pressure Tunnel. She was also encouraged to enter a training program that would put her on track to become an engineer — however, she needed special permission from the City of Hampton to take classes in math and physics at then-segregated Hampton High School.
She completed the courses, earned the promotion, and in 1958 became NASA’s first African-American female engineer. That same year, she co-authored her first report, “Effects of Nose Angle and Mach Number on Transition on Cones at Supersonic Speeds.” By 1975, she had authored or co-authored 12 NACA and NASA technical publications — most focused on the behavior of the boundary layer of air around an airplane.
Jackson eventually became frustrated with the lack of management opportunities for women in her field. In 1979, she left engineering to become NASA Langley’s Federal Women’s Program Manager to increase the hiring and promotion of NASA’s female mathematicians, engineers, and scientists.
Not only was she devoted to her career, Jackson was also committed to the advancement of her community. In the 1970s, she helped the students in the Hampton King Street Community Center build their own wind tunnel and run experiments. She and her husband Levi took in young professionals in need of guidance. She was also a Girl Scout troop leader for more than three decades.
Jackson retired from Langley in 1985. Never accepting the status quo, she dedicated her life to breaking barriers for minorities in her field. Her legacy reminds us that inclusion and diversity are needed to live up to NASA’s core values of teamwork and excellence.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
"I do not know how I may appear to the world, but to myself I seem to have been only like a boy, playing on the sea-shore, and diverting myself, in now and then finding a smoother pebble or prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me."
-Isaac Newton-
Who among us doesn’t covertly read tabloid headlines when we pass them by? But if you’re really looking for a dramatic story, you might want to redirect your attention from Hollywood’s stars to the real thing. From birth to death, these burning spheres of gas experience some of the most extreme conditions our cosmos has to offer.
All stars are born in clouds of dust and gas like the Pillars of Creation in the Eagle Nebula pictured below. In these stellar nurseries, clumps of gas form, pulling in more and more mass as time passes. As they grow, these clumps start to spin and heat up. Once they get heavy and hot enough (like, 27 million degrees Fahrenheit or 15 million degrees Celsius), nuclear fusion starts in their cores. This process occurs when protons, the nuclei of hydrogen atoms, squish together to form helium nuclei. This releases a lot of energy, which heats the star and pushes against the force of its gravity. A star is born.
Credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA)
From then on, stars’ life cycles depend on how much mass they have. Scientists typically divide them into two broad categories: low-mass and high-mass stars. (Technically, there’s an intermediate-mass category, but we’ll stick with these two to keep it straightforward!)
A low-mass star has a mass eight times the Sun’s or less and can burn steadily for billions of years. As it reaches the end of its life, its core runs out of hydrogen to convert into helium. Because the energy produced by fusion is the only force fighting gravity’s tendency to pull matter together, the core starts to collapse. But squeezing the core also increases its temperature and pressure, so much so that its helium starts to fuse into carbon, which also releases energy. The core rebounds a little, but the star’s atmosphere expands a lot, eventually turning into a red giant star and destroying any nearby planets. (Don’t worry, though, this is several billion years away for our Sun!)
Red giants become unstable and begin pulsating, periodically inflating and ejecting some of their atmospheres. Eventually, all of the star’s outer layers blow away, creating an expanding cloud of dust and gas misleadingly called a planetary nebula. (There are no planets involved.)
Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
All that’s left of the star is its core, now called a white dwarf, a roughly Earth-sized stellar cinder that gradually cools over billions of years. If you could scoop up a teaspoon of its material, it would weigh more than a pickup truck. (Scientists recently found a potential planet closely orbiting a white dwarf. It somehow managed to survive the star’s chaotic, destructive history!)
A high-mass star has a mass eight times the Sun’s or more and may only live for millions of years. (Rigel, a blue supergiant in the constellation Orion, pictured below, is 18 times the Sun’s mass.)
Credit: Rogelio Bernal Andreo
A high-mass star starts out doing the same things as a low-mass star, but it doesn’t stop at fusing helium into carbon. When the core runs out of helium, it shrinks, heats up, and starts converting its carbon into neon, which releases energy. Later, the core fuses the neon it produced into oxygen. Then, as the neon runs out, the core converts oxygen into silicon. Finally, this silicon fuses into iron. These processes produce energy that keeps the core from collapsing, but each new fuel buys it less and less time. By the point silicon fuses into iron, the star runs out of fuel in a matter of days. The next step would be fusing iron into some heavier element, but doing requires energy instead of releasing it.
The star’s iron core collapses until forces between the nuclei push the brakes, and then it rebounds back to its original size. This change creates a shock wave that travels through the star’s outer layers. The result is a huge explosion called a supernova.
What’s left behind depends on the star’s initial mass. Remember, a high-mass star is anything with a mass more than eight times the Sun’s — which is a huge range! A star on the lower end of this spectrum leaves behind a city-size, superdense neutron star. (Some of these weird objects can spin faster than blender blades and have powerful magnetic fields. A teaspoon of their material would weigh as much as a mountain.)
At even higher masses, the star’s core turns into a black hole, one of the most bizarre cosmic objects out there. Black holes have such strong gravity that light can’t escape them. If you tried to get a teaspoon of material to weigh, you wouldn’t get it back once it crossed the event horizon — unless it could travel faster than the speed of light, and we don’t know of anything that can! (We’re a long way from visiting a black hole, but if you ever find yourself near one, there are some important safety considerations you should keep in mind.)
The explosion also leaves behind a cloud of debris called a supernova remnant. These and planetary nebulae from low-mass stars are the sources of many of the elements we find on Earth. Their dust and gas will one day become a part of other stars, starting the whole process over again.
That’s a very brief summary of the lives, times, and deaths of stars. (Remember, there’s that whole intermediate-mass category we glossed over!) To keep up with the most recent stellar news, follow NASA Universe on Twitter and Facebook.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
It was previously thought that lightning on Jupiter was similar to Earth, forming only in thunderstorms where water exists in all its phases – ice, liquid, and gas. But flashes observed at altitudes too cold for pure liquid water to exist told a different story. This illustration uses data obtained by the mission to show what these high-altitude electrical storms look like.
Understanding the inner workings of Jupiter allows us to develop theories about atmospheres on other planets and exoplanets!
Illustration Credit: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt/Heidi N. Becker/Koji Kuramura
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
Are we alone? How did we get here? Where are we headed?
At NASA, our mission is to explore. We visit destinations in our solar system and study worlds beyond to better understand these big questions.
We also dream. We dream of traveling to distant worlds, and what that might be like. In the video above you can see fanciful, imagined adventures to real places we’ve studied at NASA.
Check out how we created these otherworldly scenes in the video below. A NASA videographer used green screens to add motion and real people to bring life to our series of solar system and exoplanet travel posters.
Let’s dive into one example from the video. The shot of kayaking on Titan showcases the real rivers and lakes of liquid methane and ethane that slosh and flow on Saturn's largest moon. Titan's mysterious surface was revealed by our Cassini spacecraft, which also deployed the European Space Agency’s Huygens probe to the surface. The atmosphere on Titan is so thick, and the gravity so light, that with each strike of a paddle, you might be lofted above the swift current as you ride the tides through a narrow strait called the Throat of Kraken. NASA scientist Mike Malaska studies Titan and collaborated on the poster featured in the video. His research informed the artwork, and so did a hobby: kayaking. Those ultra-cold chemical seas might be even more of a challenge than shown here. Your boat might crack, or even dissolve, Malaska said.
We’ll learn more about Titan when our Dragonfly mission of dual quadcoptors — rotorcraft with eight blades each — visits the icy moon in 2034.
Our understanding of other worlds is always evolving, and sometimes we learn new details after we illustrate our science. In one of our travel posters, we show a traveler standing on the surface of exoplanet Kepler-16b with two shadows formed by the planet’s two suns. The planet does indeed orbit two stars, but with later size and mass refinements, we now think it would be hard to stand there and enjoy a binary sunset. There isn't a solid surface to stand on a gas planet, and that's what Kepler-16b now appears to be!
In addition to sharing how sublime science can be, these scenes are a reminder that there are lots of careers in the space program, not just scientist, engineer, or astronaut. A creative team at NASA’s Jet Propulsion Laboratory in Southern California produced the travel posters, originally to help share the work of NASA's Exoplanet Exploration Program. They are the result of lots of brainstorming and discussion with real NASA scientists, engineers, and expert communicators. The video versions of these spacey travel scenes were produced by visualization experts at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
All of this work is meant to inspire, and to explore the edge of possibility. It’s also an invitation. With science, we’re stepping into the future. Join us?
Do you believe in magic? ✨ While appearing as a delicate and light veil draped across the sky, this @NASAHubble image reminds us of the power of imagination. What does this look like to you? In reality, it’s a small section of a Cygnus supernova blast wave, located around 2,400 light-years away. The original supernova explosion blasted apart a dying star about 20 times more massive than our Sun between 10,000 and 20,000 years ago. Since then, the remnant has expanded 60 light-years from its center. Credit: @ESA/Hubble & NASA, W. Blair; acknowledgment: Leo Shatz