BLOGS

The sample return capsule from NASA's OSIRIS-REx mission is seen shortly after touching down in the desert at the Department of Defense's Utah Test and Training Range. Keegan Barber/NASA

Topics: Asteroids, Astrobiology, Astrophysics, NASA, Space Exploration

Scientists are exulting over the safe arrival of a canister containing about a cup's worth of asteroid rocks, collected 200 million miles away, that landed in a Utah desert after a 7-year NASA mission sent to retrieve them.

The black pebbles and dirt are older than Earth and are undisturbed remnants of the solar system's early days of planet formation. As part of an asteroid named Bennu, these rocks traveled unsullied through space for eons.

While bits of asteroids regularly fall to our planet as meteorites, scientists want to study pristine asteroid material, stuff that's uncontaminated by our planet, to understand the early chemistry that might have contributed to the emergence of life.

NASA asteroid sample lands safely in Utah before being whisked away by helicopter, Nell Greenfieldboyce, NPR

Artist's conception of the dwarf planet Sedna in the outer edges of the known solar system. (Image credit: NASA/JPL-Caltech/R. Hurt (SSC))

Topics: Astronomy, Astrophysics, Exoplanets, NASA, Space Exploration

Astronomers are racing to explain the peculiar orbits of faraway objects at the edge of our solar system.

Among the many mysteries that make the furthest reaches of our solar system, well, mysterious, is the exceptionally egg-shaped path of a dwarf planet called 90377 Sedna.

Its 11,400-year orbit, one of the longest of any resident of the solar system, ushers the dwarf planet to seven billion miles (11.3 billion km) from the sun, then escorts it out of the solar system and way past the Kuiper Belt to 87 billion miles (140 billion km), and finally takes it within a loose shell of icy objects known as the Oort cloud. Since Sedna's discovery in 2003, astronomers have struggled to explain how such a world could have formed in a seemingly empty region of space, where it is too far to be influenced by giant planets of the solar system and even the Milky Way galaxy itself.

Now, a new study suggests that a thus far undetected Earth-like planet hovering in that region could be deviating orbits of Sedna and a handful of similar trans-Neptunian objects (TNOs), which are the countless icy bodies orbiting the sun at gigantic distances. Many TNOs have oddly inclined and egg-shaped orbits, possibly due to being tugged at by a hidden planet, astronomers say.

Could an 'Earth-like' planet be hiding in our solar system's outer reaches? Sharmila Kuthunur, Space.com

Valentina Tereshkova. Credit: ESA

Topics: Astronautics, ESA, History, NASA, Space Exploration, Spaceflight, Women in Science

The first female cosmonaut flew years before NASA put a man on the Moon and decades before any other country would send a woman into orbit.

On a drab Sunday in Moscow in November 1963, a dark-suited man stood beside his veiled bride, whose bashful smile betrayed the merest hint of nerves. Despite the extraordinarily lavish surroundings of the capital’s Wedding Palace, it might have been any normal wedding, but for one thing: Both groom and bride were cosmonauts, members of Russia’s elite spacefaring fraternity.

Two years earlier, that bride, Valentina Tereshkova, had been a factory seamstress and amateur parachutist with more than 100 jumps to her name when she’d volunteered for the cosmonaut program. Now, the 26-year-old, whom TIME magazine dubbed “a tough-looking Ingrid Bergman,” was among the most famous women in the world, an accolade she had earned just months ago by becoming the first female to leave the planet.

Sixty years on from her pioneering Vostok 6 mission, more than 70 women from around the globe have followed in Tereshkova’s footsteps, crossing that ethereal boundary between ground and space. Some have commanded space missions, helmed space stations, made spacewalks, spent more than a cumulative year of their lives in orbit, and even flown with a prosthesis. And women from Britain, Iran, and South Korea have become their countries’ first national astronauts, ahead of their male counterparts.

60 years ago today, Valentina Tereshkova launched into space, Ben Evans, Astronomy

The galaxy observed by Webb shows an Einstein ring caused by a phenomenon known as gravitational lensing.  Credit: S. Doyle / J. Spilker

Topics: Astrobiology, Biology, James Webb Space Telescope, Space Exploration

Researchers have detected complex organic molecules in a galaxy more than 12 billion light-years away from Earth—the most distant galaxy in which these molecules are now known to exist. Thanks to the capabilities of the recently launched James Webb Space Telescope and careful analyses from the research team, a new study lends critical insight into the complex chemical interactions that occurred in the first galaxies in the early universe.

University of Illinois Urbana-Champaign astronomy and physics professor Joaquin Vieira and graduate student Kedar Phadke collaborated with researchers at Texas A&M University and an international team of scientists to differentiate between infrared signals generated by some of the more massive and larger dust grains in the galaxy and those of the newly observed hydrocarbon molecules.

The study findings are published in the journal Nature.

"This project started when I was in graduate school studying hard-to-detect, very distant galaxies obscured by dust," Vieira said. "Dust grains absorb and re-emit about half of the stellar radiation produced in the universe, making infrared light from distant objects extremely faint or undetectable through ground-based telescopes."

In the new study, the JWST received a boost from what the researchers call "nature's magnifying glass"—a phenomenon called gravitational lensing. "This magnification happens when two galaxies are almost perfectly aligned from the Earth's point of view, and light from the background galaxy is warped and magnified by the foreground galaxy into a ring-like shape, known as an Einstein ring," Vieira said.

Webb Space Telescope detects the universe's most distant complex organic molecules, Lois Yoksoulian, University of Illinois at Urbana-Champaign.

The Artemis 2 crew, from left to right: Jeremy Hansen, Reid Wiseman, Victor Glover, and Christina Koch. (NASA TV)

Topics: Astronautics, Astrophysics, International Space Station, NASA, Space Exploration

NASA has selected the four astronauts that will travel to the Moon during the upcoming Artemis 2 mission, which will be humanity’s first crewed return to the Moon in more than 50 years.

The four astronauts are Reid Wiseman, Victor Glover, and Christina Koch of NASA, and Jeremy Hansen of the Canadian Space Agency.

“The Artemis 2 crew represents thousands of people working tirelessly to bring us to the stars,” said NASA Administrator Bill Nelson before announcing the crew during a live event broadcast on NASA TV. “This is their crew. This is our crew. This is humanity’s crew.”

Meet the Four Astronauts Who Will Soon Take a Trip to the Moon, Jake Parks, Discovery Magazine

Related: NC astronaut Christina Koch will be part of NASA Artemis II moon mission, Korie Dean, The Charlotte Observer

Topics: Astronomy, Astrophysics, Exoplanets, Space Exploration

In 2008, HR8799 was the first extrasolar planetary system ever directly imaged. Now, the famed system stars in its very own video.

Using observations collected over the past 12 years, Northwestern University astrophysicist Jason Wang has assembled a stunning time-lapse video of the family of four planets — each more massive than Jupiter — orbiting their star. The video gives viewers an unprecedented glimpse into planetary motion.

“It’s usually difficult to see planets in orbit,” Wang said. “For example, it isn’t apparent that Jupiter or Mars orbit our sun because we live in the same system and don’t have a top-down view. Astronomical events happen too quickly or slowly to capture in a movie. But this video shows planets moving on a human time scale. I hope it enables people to enjoy something wondrous.”

An expert in exoplanet imaging, Wang is an assistant professor of physics and astronomy at Northwestern’s Weinberg College of Arts and Sciences and a member of the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA).

Watch distant worlds dance around their sun, Amanda Morris, Northwestern University.

Life on other planets might not look like any beings we’re used to on Earth. It may even be unrecognizable at first to scientists searching for it. Credit: William Hand

Topics: Astrobiology, Astronomy, Astrophysics, Planetary Science, SETI, Space Exploration

Sarah Stewart Johnson was a college sophomore when she first stood atop Hawaii’s Mauna Kea volcano. Its dried lava surface differed from the eroded, tree-draped mountains of her home state of Kentucky. Johnson wandered away from the other young researchers she was with and toward a distant ridge of the 13,800-foot summit. Looking down, she turned over a rock with the toe of her boot. To her surprise, a tiny fern lived underneath it, sprouting from ash and cinder cones. “It felt like it stood for all of us, huddled under that rock, existing against the odds,” Johnson says.

Her true epiphany, though, wasn’t about the hardiness of life on Earth or the hardships of being human: It was about aliens. Even if a landscape seemed strange and harsh from a human perspective, other kinds of life might find it quite comfortable. The thought opened up the cosmic real estate and the variety of life she imagined might be beyond Earth’s atmosphere. “It was on that trip that the idea of looking for life in the universe began to make sense to me,” Johnson says.

Later, Johnson became a professional at looking. As an astronomy postdoc at Harvard University in the late 2000s and early 2010s, she investigated how astronomers might use genetic sequencing—detecting and identifying DNA and RNA—to find evidence of aliens. Johnson found the work exciting (the future alien genome project!), but it also made her wonder: What if extraterrestrial life didn’t have DNA, RNA, or other nucleic acids? What if their cells got instructions in some other biochemical way?

As an outlet for heretical thoughts like this, Johnson started writing in style too lyrical and philosophical for scientific journals. Her typed musings would later turn into the 2020 popular science book The Sirens of Mars. Inside its pages, she probed the idea that other planets were truly other. So their inhabitants might be very different, at a fundamental and chemical level, from anything in this world. “Even places that seem familiar—like Mars, a place that we think we know intimately—can completely throw us for a loop,” she says. “What if that’s the life case?”

The Search for Extraterrestrial Life as We Don’t Know It, Sarah Scoles, Scientific American

An Orbitrap cell. Credit: Ricardo Arevalo

Topics: Astrobiology, Astronautics, Biology, Laser, NASA, Planetary Science, Space Exploration

As space missions delve deeper into the outer solar system, the need for more compact, resource-conserving, and accurate analytical tools have become increasingly critical—especially as the hunt for extraterrestrial life and habitable planets or moons continues.

A University of Maryland–led team developed a new instrument specifically tailored to the needs of NASA space missions. Their mini laser-sourced analyzer is significantly smaller and more resource efficient than its predecessors—all without compromising the quality of its ability to analyze planetary material samples and potential biological activity onsite. The team's paper on this new device was published in the journal Nature Astronomy on January 16, 2023.

Weighing only about 17 pounds, the instrument is a physically scaled-down combination of two important tools for detecting signs of life and identifying compositions of materials: a pulsed ultraviolet laser that removes small amounts of material from a planetary sample and an Orbitrap analyzer that delivers high-resolution data about the chemistry of the examined materials.

"The Orbitrap was originally built for commercial use," explained Ricardo Arevalo, lead author of the paper and an associate professor of geology at UMD. "You can find them in the labs of pharmaceutical, medical and proteomic industries. The one in my own lab is just under 400 pounds, so they're quite large, and it took us eight years to make a prototype that could be used efficiently in space—significantly smaller and less resource-intensive but still capable of cutting-edge science."

The team's new gadget shrinks down the original Orbitrap while pairing it with laser desorption mass spectrometry (LDMS)—techniques that have yet to be applied in an extraterrestrial planetary environment. The new device boasts the same benefits as its larger predecessors but is streamlined for space exploration and onsite planetary material analysis, according to Arevalo.

Small laser device can help detect signs of life on other planets, University of Maryland, Phys.org.

An artist’s concept of New Horizons during the spacecraft’s planned encounter with Pluto and its moon Charon. The craft’s miniature cameras, radio science experiments, ultraviolet and infrared spectrometers, and space plasma experiments would characterize the global geology and geomorphology of Pluto and Charon, map their surface compositions and temperatures, and examine Pluto’s atmosphere in detail. Credit: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)

Topics: Astronomy, Astrophysics, NASA, Planetary Science, Space Exploration

Only two spacecraft have ever left our solar system and lived to tell the tale. In 2012 and 2019, NASA’s Voyager 1 and 2 spacecraft respectively broke through the heliopause, the boundary at which our sun’s sphere of influence gives way to the interstellar medium. They have sent back remarkable riches from this distant location, humanity’s first foray into the limitless bounds beyond our solar system’s edge. Hot pursuit is a far more advanced vehicle, sporting improved instruments, updated optics, and even a means to sample the interstellar medium itself. New Horizons was launched from Earth in 2006 on a mission to visit Pluto, arriving in 2015 and revealing incredible details during its all-too-brief flyby. The spacecraft has continued its cruise toward interstellar frontiers ever since. It has now begun its second extended mission. It is soon set to wake up from a deep hibernation, opening a wealth of new scientific opportunities in the outer solar system. “It takes a long time to get to where our spacecraft is,” says Alice Bowman, mission operations manager for New Horizons at the Johns Hopkins University Applied Physics Laboratory (JHUAPL) in Maryland. “When you have a spacecraft that is out in that part of the solar system, it is a huge asset to the scientific community. There are so many unique things that a spacecraft that is out that far can do. We definitely want to take advantage of that.”

For New Horizons, those “unique things” include unprecedented studies of the planets Uranus and Neptune, sampling of the local dust, studies of the background light in the universe, and more. The sum total will be a new phase of the mission that is “really unique and interdisciplinary in nature,” says Alan Stern, the lead on the mission at the Southwest Research Institute (SwRI) in Texas. In October, this two-year second extended mission officially began, but in 2023 it will pick up the pace as the spacecraft exits hibernation and begins its scientific program in earnest. “There were lots of good ideas for how to do things in astrophysics, heliophysics, and planetary science,” Stern says. “We took the very best of those.” There is even the tantalizing possibility of visiting another object in the Kuiper Belt, the region of asteroids and icy objects that lurks beyond Neptune, in which New Horizons has already visited one object—Arrokoth in 2019—after its Pluto encounter. Even without such a possibility, there was more than enough reason for NASA to extend the mission. “New Horizons is at a unique location in the solar system with an amazing suite of functioning instruments on board,” says Becky McCauley Rench, New Horizons program scientist at NASA Headquarters in Washington, D.C. “[It] can provide valuable insights to the heliosphere and the solar wind, astronomical observations of the cosmic background radiation, and valuable data about Uranus and Neptune that can be applied to our knowledge about ice giant planets.”

NASA’s Pluto Spacecraft Begins New Mission at the Solar System’s Edge, Jonathan O'Callaghan, Scientific American

Credit: NASA, ESA, CSA, and Jupiter ERS Team; Image processing by Ricardo Hueso/UPV/EHU and Judy Schmidt

Topics: Astronomy, Astrophysics, Planetary Science, Space Exploration

Jupiter's rings, its moons Amalthea (the bright point at left), Adrastea (the faint dot at the left tip of rings), and even background galaxies are visible in this image from JWST's NIRCam instrument. Whiter areas on the planet represent regions with more cloud cover, which reflects sunlight, especially Jupiter's famous Great Red Spot; darker spots have fewer clouds. Perhaps the most stunning feature is the blue glow of the planet's auroras at the north and south poles. This light shows results when high-energy particles streaming off the sun hit atoms in Jupiter's atmosphere. Auroras are found on any planet with an atmosphere and a magnetic field, which steers the sun's particles to the poles; besides Earth and Jupiter, telescopes have seen auroras on Saturn, Uranus, and Neptune.

The Best of JWST’s Cosmic Portraits, Clara Moskowitz, Scientific American

Topics: Civilization, International Space Station, Politics, Space Exploration

ALMATY, March 30 (Reuters) - A U.S. astronaut and two Russian cosmonauts safely landed in Kazakhstan on Wednesday after leaving the International Space Station aboard the same capsule despite heightened antagonism between Moscow and Washington over the conflict in Ukraine.

The flight -- carrying NASA's Mark Vande Hei and Russians Anton Shkaplerov and Pyotr Dubrov back to Earth -- had been closely watched to determine whether escalating strife had spilled over into longtime cooperation in space between the two former Cold War adversaries.

Russian space agency Roscosmos broadcast footage of the landing from the Kazakh steppe and said a group of technical and medical specialists had been dispatched to help the astronauts out of the capsule.

"The crew is feeling good after landing, according to rescuers," Roscosmos chief Dmitry Rogozin wrote on Telegram messenger.

Vande Hei, who had completed his second ISS mission, logged a U.S. space-endurance record of 355 consecutive days in orbit, surpassing the previous 340-day record set by astronaut Scott Kelly in 2016, according to NASA.

U.S. astronaut, two Russian cosmonauts return home from ISS, Olzhas Auyezov and Steve Gorman, Reuters

An artist’s impression of the newly discovered planet orbiting Proxima Centauri.Credit: ESO/L. Calçada

Topics: Astronomy, Astrophysics, Exoplanets, Space Exploration, Spaceflight

Astronomers have discovered a third planet orbiting Proxima Centauri, the star closest to the Sun. Called Proxima Centauri d, the newly spotted world is probably smaller than Earth and could have oceans of liquid water.

“It’s showing that the nearest star probably has a very rich planetary system,” says Guillem Anglada-Escudé, an astronomer at the Institute of Space Sciences in Barcelona, Spain, who led the team that, in 2016, discovered the first planet to be seen orbiting Proxima Centauri.

Astronomer João Faria and his collaborators detected Proxima Centauri d by measuring tiny shifts in the spectrum of light from the star as the planet’s gravity pulled at it during orbit. The team used a state-of-the-art instrument called the Echelle Spectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO) at the Very Large Telescope, a system of four 8.2-meter telescopes at the European Southern Observatory in Cerro Paranal, Chile. The results were published on 10 February in Astronomy & Astrophysics.

Earth-like planet spotted orbiting Sun’s closest star, Davide Castelvecchi, Nature

Artist's rendition of a future colony on Mars., e71lena via Shutterstock

Topics: Applied Physics, Energy, Mars, Space Exploration

(Inside Science) -- Mars is known for its dust storms, which can cause problems for lander equipment and block out the sun that fuels solar panels. These punishing storms, which can last for weeks, have already caused damage to equipment and even killed NASA’s Opportunity rover. But they could also be dangerous to astronauts on the ground, who would rely on solar power for oxygen, heat, and water cleansing during future missions.

Vera Schorbach, a professor of wind energy at the Hamburg University of Applied Sciences in Germany, was curious to see whether wind turbines could harness the power of these storms, filling in for solar panels on the Red Planet during times of need.

"I asked myself, 'Why don't they have a wind turbine if they have dust storms,'" said Schorbach, the lead author of a study about the potential for wind power on Mars published recently in the journal Acta Astronautica.

Could martian dust storms help astronauts keep the lights on? Joshua Rapp Leam, Astronomy/Inside Science

FIG. 1. Temporal evolution of chamber pressure assuming nominal operation for 30 s followed by a 40 s interval with flow rate reduced 100×. The colors correspond to 1 kW, 10 kW, 100 kW, and 1 MW power levels. The process is then repeated.

Topics: Applied Physics, Computer Modeling, NASA, Space Exploration, Spaceflight

Abstract

Hall effect thrusters operating at power levels in excess of several hundreds of kilowatts have been identified as enabling technologies for applications such as lunar tugs, large satellite orbital transfer vehicles, and solar system exploration. These large thrusters introduce significant testing challenges due to the propellant flow rate exceeding the pumping speed available in most laboratories. Even with proposed upgrades in mind, the likelihood that multiple vacuum facilities will exist in the near future to allow long-duration testing of high-power Hall thrusters operating at power levels in excess of 100 kW remains extremely low. In this article, we numerically explore the feasibility of testing Hall thrusters in a quasi-steady mode defined by pulsing the mass flow rate between a nominal and a low value. Our simulations indicate that sub-second durations available before the chamber reaches critical pressure are sufficiently long to achieve the steady-state current and flow field distributions, allowing us to characterize thruster performance and the near plume region.

I. INTRODUCTION

Hall effect thrusters (HETs) are spacecraft electric propulsion (EP) devices routinely used for orbit raising, repositioning, and solar system exploration applications. To date, the highest power Hall thruster flown is the 4.5 kW BPT-4000 launched in 2010 aboard the Advanced EHF satellite¹ (which the HET helped to deliver to the correct orbit after a failure of the primary chemical booster), although a 13 kW system is being readied for near-term flight operation as part of the Lunar Gateway,² and thrusters at 50^3,4–100 kW^s power levels have been demonstrated in the laboratory. Solar cell advancements and a renewed interest in nuclear power have led the aerospace community to consider the use of Hall thrusters operating at even higher power levels. Multi-hundred kW EP systems would offer an economical solution for LEO to GEO orbit raising or for the deployment of an Earth-to-Moon delivery tug, and power levels in excess of 600 kW could be utilized for crewed transport to Mars.^5–9 While such power levels could be delivered using existing devices, a single large thruster requires less system mass and has a reduced footprint than a cluster of smaller devices.¹⁰

Quasi-steady testing approach for high‐power Hall thrusters, Lubos Brieda, Yevgeny Raitses, Edgar Choueiri, Roger Myers, Michael Keidar, Journal of Applied Physics

The depiction of tentacled extraterrestrials (above) in the recent science-fiction film, "Arrival, "indicates divergence from aliens reported by supposed eyewitness accounts. Paramount. Source: Wrinkles, tentacles and oval eyes: How depictions of aliens have evolved, CNN Style

Topics: Astrobiology, Philosophy, SETI, Space Exploration

In my freshman seminar at Harvard last semester, I mentioned that the nearest star to the sun, Proxima Centauri, emits mostly infrared radiation and has a planet, Proxima b, in the habitable zone around it. As a challenge to the students, I asked: “Suppose there are creatures crawling on the surface of Proxima b? What would their infrared-sensitive eyes look like?” The brightest student in class responded within seconds with an image of the mantis shrimp, which possesses infrared vision. The shrimp’s eyes look like two ping-pong balls connected with cords to its head. “It looks like an alien,” she whispered.

When trying to imagine something we’ve never seen, we often default to something we have seen. For that reason, in our search for extraterrestrial life, we are usually looking for life as we know it. But is there a path for expanding our imagination to life as we don’t know it?

In physics, an analogous path was already established a century ago and turned out to be successful in many contexts. It involves conducting laboratory experiments that reveal the underlying laws of physics, which in turn apply to the entire universe. For example, around the same time when the neutron was discovered in the laboratory of James Chadwick in 1932, Lev Landau suggested that there might be stars made of neutrons. Astronomers realized subsequently that there are, in fact, some 100 million neutron stars in our Milky Way galaxy alone—and a billion times more in the observable universe. Recently, the LIGO experiment detected gravitational wave signals from collisions between neutron stars at cosmological distances. It is now thought that such collisions produce the precious gold that is forged into wedding bands. The moral of this story is that physicists were able to imagine something new in the universe at large and search for it in the sky by following insights gained from laboratory experiments on Earth.

How to Search for Life as We Don't Know It, Avi Loeb, Scientific American

Topics: Diversity in Science, NASA, Space Exploration, Spaceflight, SpaceX, Star Trek

Dr. King revealed to Nichols that TOS was the only show that he and his wife, Coretta, allowed their little children to stay up and watch. Further, he told Nichols what the show meant to him personally and detailed the importance of her having created a character with "dignity and knowledge." Nichols took it all in and finally said, “Thank you so much, Dr. King. I’m really going to miss my co-stars.” Dr. King's smile, Nichols recalled, vanished from his face.

"He said, 'What are you talking about?'" the actress explained. "I told him. He said, 'You cannot,' and so help me, this man practically repeated verbatim what Gene said. He said, 'Don’t you see what this man is doing, who has written this? This is the future. He has established us as we should be seen. Three hundred years from now, we are here. We are marching. And this is the first step. When we see you, we see ourselves, and we see ourselves as intelligent and beautiful and proud.' He goes on and I’m looking at him and my knees are buckling. I said, 'I…, I…' And he said, 'You turn on your television and the news comes on and you see us marching and peaceful, you see the peaceful civil disobedience, and you see the dogs and see the fire hoses, and we all know they cannot destroy us because we are there in the 23rd century.'

Nichelle Nichols Remembers Dr. King, the StarTrek.com staff

Note: At this posting, she made history yesterday.

Sian Proctor is making history as the first-ever Black female spacecraft pilot. 

Proctor, a geoscientist, artist, and science communicator, has been paving the way in the space sector for decades. Now, years after being a finalist in NASA's astronaut candidate program back in 2009, she is realizing her dream of becoming an astronaut as she launches to orbit with the Inspiration4 mission tonight (Sept. 15).

While the mission itself is making history as the first all-civilian mission to launch to orbit, Proctor is accomplishing a major first herself as the first Black female spacecraft pilot. 

"I'm really grateful to be here and to have this opportunity," Proctor said Sept. 14 during a news conference with reporters. "There have been three Black female astronauts that have made it to space, and knowing that I'm going to be the fourth means that I have this opportunity to not only accomplish my dream but also inspire the next generation of women of color and girls of color and really get them to think about reaching for the stars and what that means."

Sian Proctor makes history with SpaceX's Inspiration4 as first-ever Black female spacecraft pilot, Chelsea Gohd, Space.com

Hot and humid The surface of a Hycean planet as interpreted by an artist. (Courtesy: Amanda Smith, University of Cambridge).

Topics: Astronomy, Astrophysics, Astrobiology, Exoplanets, Space Exploration

Hot, ocean-covered exoplanets with hydrogen-rich atmospheres could harbor life and may be more common than planets that are Earth-like in size, temperature, and atmospheric composition. According to astronomers at the University of Cambridge, UK, this newly defined class of exoplanets could boost the search for life elsewhere in the universe by broadening the search criteria and redefining which biosignatures are important.

Astronomers define the habitable or “Goldilocks” zone as the region where an exoplanet is neither too close nor too far from its host star to have liquid water on its surface – water being the perfect solvent for many forms of life. Previous studies of planetary habitability have focused primarily on searching for Earth-like exoplanets and evidence that they could harbor the kind of chemistry found in life on Earth. However, it has so far proven difficult to detect atmospheric signatures from Earth-like planets orbiting Sun-like stars.

Potentially habitable mini-Neptunes

Larger exoplanets are easier to detect than smaller, Earth-sized ones, and exoplanets around 1.6‒4 times bigger than the Earth, with masses of up to 15 Earth masses and temperatures that in some cases exceed 2000 K, are relatively common. These planets are known as mini-Neptune's as they are similar to the ice giant planets in our solar system.

Previous studies suggested that the high pressures and temperatures beneath these planets’ hydrogen-rich atmospheres were incompatible with life. However, based on their analysis of an exoplanet called K2-18b, exoplanet scientist Nikku Madhusudhan and colleagues at Cambridge say that life could, in fact, exist on a subset of mini-Neptunes that meet specific criteria.

This subset, which the researchers dub “Hycean” (hydrogen + ocean) planets, consists of planets that have radii up to 2.6 times larger than Earth’s and are capable of harboring vast oceans under atmospheres dominated by molecular hydrogen and water vapor. Such oceans could cover the whole planet and reach depths greater than the Earth’s oceans, and the researchers say that the conditions within them could be compatible with some forms of Earth-based microbial life. Hycean planets tidally locked with their host star could also exhibit habitable conditions on their permanent night side.

Astronomers define new class of potentially habitable ocean worlds, Chaneil James, Physics World

Topics: Materials Science, Nanotechnology, Space Exploration, Spaceflight, Star Trek

China is investigating how to build ultra-large spacecraft that are up to 0.6 miles (1 kilometer) long. But how feasible is the idea, and what would be the use of such a massive spacecraft?

The project is part of a wider call for research proposals from the National Natural Science Foundation of China, a funding agency managed by the country’s Ministry of Science and Technology. A research outline posted on the foundation’s website described such enormous spaceships as “major strategic aerospace equipment for the future use of space resources, exploration of the mysteries of the universe, and long-term living in orbit.”

The foundation wants scientists to conduct research into new, lightweight design methods that could limit the amount of construction material that has to be lofted into orbit, and new techniques for safely assembling such massive structures in space. If funded, the feasibility study would run for five years and have a budget of 15 million yuan ($2.3 million).

The project might sound like science fiction, but former NASA chief technologist Mason Peck said the idea isn’t entirely off the wall, and the challenge is more a question of engineering than fundamental science.

“I think it’s entirely feasible,” Peck, now a professor of aerospace engineering at Cornell University, told Live Science. “I would describe the problems here not as insurmountable impediments, but rather problems of scale.”

By far the biggest challenge would be the price tag, noted Peck, due to the huge cost of launching objects and materials into space. The International Space Station (ISS), which is only 361 feet (110 meters) wide at its widest point according to NASA, cost roughly $100 billion to build, Peck said, so constructing something 10 times larger would strain even the most generous national space budget.

China Wants to Build a Mega Spaceship That’s Nearly a Mile Long, Edd Gent, Scientific American

Image source: The Roddenberry Foundation link below

Topics: Planetary Science, Space Exploration, Spaceflight, Star Trek

NASA is helping the legacy of inspiration, hope, and diversity fostered by the creator of Star Trek to live long and prosper. The agency will observe the late Gene Roddenberry’s 100th birthday with a special program called, Celebrating Gene Roddenberry: Star Trek's Bridge and NASA – a panel discussion airing on NASA Television, the agency’s website, the NASA App, and NASA social media at 2 p.m. EDT Thursday, Aug. 19.

The program includes introductory remarks by NASA Administrator Bill Nelson followed by a panel discussion moderated by Rod Roddenberry, son of Gene Roddenberry. Special guest George Takei, a Star Trek actor, and activist will participate in the question-and-answer session.

Coinciding with the program, NASA will broadcast into space a 1976 recording of Gene Roddenberry's remarks on diversity and inclusion through the agency’s Deep Space Network of radio antennas. NASA also is inviting people on social media to join in celebrating Roddenberry’s 100th birthday on Thursday by posting a Vulcan salute selfie with the hashtag #Roddenberry100.

The Roddenberry Foundation Centennial Celebration

NASA

Image Source: Link below

Topics: Astrophysics, Planetary Science, SETI, Space Exploration

Even as a child, before he devoted his life to the search for extraterrestrial life, Frank Drake wondered whether Earth was alone in its ability to harbor life. He wasn’t the first or the only one to wonder. There’s a reason so many are fascinated by the question: Its answer helps reveal humankind’s place in the cosmos.

Drake’s musings inspired him to pursue astronomy, serving as director of the Arecibo Observatory in Puerto Rico and president of the SETI Institute — which, as the acronym suggests, is devoted to the Search for Extraterrestrial Intelligence, and exploring the possibilities of life elsewhere in the universe. Drake is perhaps most famous for his eponymous equation — an estimate of how many alien civilizations might exist in our galaxy. Presented in 1961, the equation is generally considered as the start of a new era of searches for extraterrestrial intelligence.

But decades after the invention of that famous equation, Drake has conceded that his estimates were overly conservative. Among the too-moderate assumptions was that a potentially inhabited other world must be orbiting a star — overlooking the possibility of life on rogue planets.

Sometimes called “nomads of the galaxy” or “orphan planets,” these cold, dark worlds careen through space with no home, no solar system, no sun to orbit. Long ago, they formed around a star but were flung out, abandoned by their parents. There are billions of rogue planets — astronomers estimate there could be at least one for every star — wandering the galaxy.

It may seem futile to search for life in such cold, desolate environments, but over the last two decades, astronomers have come up with a number of possible scenarios that would make life possible on a planet without a star.

Can Life Exist on a Rogue Planet? Katie McCormick, Discovery Magazine