Universe Today

February 17, 2024February 17, 2024 by Matt Williams

Can the Gaia Hypothesis Be Tested in the Lab?

A new paper proposes an experimental setup that could test the classic Daisyworld model — a hypothesis of a self-regulating planetary ecosystem — in the lab via two synthetic bacterial strains. Credit: Victor Maull/Image Designer

During the 1970s, inventor/environmentalist James Lovelock and evolutionary biologist Lynn Margulis proposed the Gaia Hypothesis. This theory posits that Earth is a single, self-regulating system where the atmosphere, hydrosphere, all life, and their inorganic surroundings work together to maintain the conditions for life on the planet. This theory was largely inspired by Lovelock’s work with NASA during the 1960s, where the skilled inventor designed instruments for modeling the climate of Mars and other planets in the Solar System.

According to this theory, planets like Earth would slowly grow warmer and their oceans more acidic without a biosphere that regulates temperature and ensures climate stability. While the theory was readily accepted among environmentalists and climatologists, many in the scientific community have remained skeptical since it was proposed. Until now, it has been impossible to test this theory because it involves forces that work on a planetary scale. But in a recent paper, a team of Spanish scientists proposed an experimental system incorporating synthetic biology that could test the theory on a small scale.

February 16, 2024February 16, 2024 by Andy Tomaswick

New NASA Report Suggests We Could See Space-Based Power After 2050

Space-based solar power (SBSP) has been in the news recently, with the successful test of a solar power demonstrator in space taking place last summer. While the concept is fundamentally sound, there are plenty of hurdles to overcome if the technology is to be widely adopted – not the least of which is cost. NASA is no stranger to costly projects, though, and they recently commissioned a study from their internal Office of Technology, Policy, and Strategy that suggests how NASA could continue to support this budding idea. Most interestingly, if the technological cards are played right, SBSP could be the most carbon-efficient, lowest-cost power source for humanity by 2050.

February 16, 2024February 16, 2024 by Evan Gough

NASA is Done Setting Fires Inside its Doomed Cargo Spacecraft

NASA's Saffire program is a series of experiments designed to understand how fire behaves in a spacecraft. In this image, a sample of fabric burns inside an uncrewed Cygnus cargo craft during a previous Spacecraft Fire Safety Experiment investigation, Saffire-IV. Image Credit: NASA

Fire on a spacecraft can be catastrophic. It can spread quickly in a confined space, and for trapped astronauts, there may be no escape. It’s fading in time now, but Apollo 1, which was to be the first crewed Apollo mission, never got off the ground because of a fire that killed the crew. There’ve been other dangerous spacecraft fires too, like the one onboard the Russian Mir space station in 1997.

In an effort to understand how fire behaves in spacecraft, NASA began its Saffire (Spacecraft Fire Safety Experiment) in 2016. Saffire was an eight-year, six-mission effort to study how fire behaves in space. The final Saffire test was completed on January 9th.

February 16, 2024February 17, 2024 by Brian Koberlein

Euclid Begins its 6-Year Survey of the Dark Universe

The areas that the space telescope Euclid will observe. Credit: ESA/Euclid/Euclid Consortium

On July 1, 2023, the Euclid Spacecraft launched with a clear mission: to map the dark and distant Universe. To achieve that goal, over the next 6 years, Euclid will make 40,000 observations of the sky beyond the Milky Way. From this data astronomers will be able to map the positions of billions of galaxies, allowing astronomers to observe the effects of dark matter.

February 15, 2024February 15, 2024 by Evan Gough

OSIRIS-REx’s Final Haul: 121.6 Grams from Asteroid Bennu

These eight sample trays contain the final material from asteroid Bennu. The dust and rocks were poured into the trays from the top plate of the Touch-and-Go Sample Acquisition Mechanism (TAGSAM) head. 51.2 grams were collected from this pour, bringing the final mass of asteroid sample to 121.6 grams. Credit: NASA/Erika Blumenfeld & Joseph Aebersold

After several months of meticulous, careful work, NASA has the final total for their haul of asteroidal material from the OSIRIS-REx mission to Bennu. The highly successful mission successfully collected 121.6 grams, or almost 4.3 ounces, of rock and dust. It won’t be long before scientists get their hands on these samples and start analyzing them.

February 15, 2024February 15, 2024 by Carolyn Collins Petersen

Even Stars Like the Sun Can Unleash Savage Flares in Their Youth

Artist's concept of the flare that burst out from the young nearby star HD 283572. The flare was detected by the Submillimeter Array on Mauna Kea, in Hawai'i. Credit: CfA/Melissa Weiss.

Why would a young Sun-like star suddenly belch out a hugely bright flare? That’s what astronomers at Harvard Smithsonian Astrophysical Observatory want to know after they spotted such an outburst using a sensitive submillimeter-wave telescope. According to Joshua Bennett Lovell, leader of a team that observed the star’s activity, these kinds of flare events are rare in such young stars, particularly at millimeter wavelengths. So, what’s happening there?

February 15, 2024February 15, 2024 by Matt Williams

Ground-Based Lasers Could Accelerate Spacecraft to Other Stars

An artist's illustration of a light-sail powered by a radio beam (red) generated on the surface of a planet. The leakage from such beams as they sweep across the sky would appear as Fast Radio Bursts (FRBs), similar to the new population of sources that was discovered recently at cosmological distances. Credit: M. Weiss/CfA

The future of space exploration includes some rather ambitious plans to send missions farther from Earth than ever before. Beyond the current proposals for building infrastructure in cis-lunar space and sending regular crewed missions to the Moon and Mars, there are also plans to send robotic missions to the outer Solar System, to the focal length of our Sun’s gravitational lens, and even to the nearest stars to explore exoplanets. Accomplishing these goals requires next-generation propulsion that can enable high thrust and consistent acceleration.

Focused arrays of lasers – or directed energy (DE) – and lightsails are a means that is being investigated extensively – such as Breakthrough Starshot and Swarming Proxima Centauri. Beyond these proposals, a team from McGill University in Montreal has proposed a new type of directed energy propulsion system for exploring the Solar System. In a recent paper, the team shared the early results of their Laser-Thermal Propulsion (LTP) thruster facility, which suggests that the technology has the potential to provide both high thrust and specific impulse for interstellar missions.

February 15, 2024February 15, 2024 by Evan Gough

Even if We Can’t See the First Stars, We Could Detect Their Impact on the First Galaxies

Population III stars were the Universe's first stars. They were extremely massive, luminous stars, and many of them exploded as supernovae. How did they shape the early galaxies? Image Credit: DALL-E — Population III stars were the Universe's first stars. They were extremely massive, luminous stars, and many of them exploded as supernovae. Image Credit: DALL-E

For a long time, our understanding of the Universe’s first galaxies leaned heavily on theory. The light from that age only reached us after travelling for billions of years, and on the way, it was obscured and stretched into the infrared. Clues about the first galaxies are hidden in that messy light. Now that we have the James Webb Space Telescope and its powerful infrared capabilities, we’ve seen further into the past—and with more clarity—than ever before.

The JWST has imaged some of the very first galaxies, leading to a flood of new insights and challenging questions. But it can’t see individual stars.

How can astronomers detect their impact on the Universe’s first galaxies?

February 15, 2024February 15, 2024 by Brian Koberlein

Another Clue Into the True Nature of Fast Radio Bursts

Artist's concept of a magnetar. Credit: NASA/JPL-Caltech

Fast radio bursts (FRBs) are strange events. They can last only milliseconds, but during that time can outshine a galaxy. Some FRBs are repeaters, meaning that they can occur more than once from the same location, while others seem to occur just once. We still aren’t entirely sure what causes them, or even if the two types have the same cause. But thanks to a collaboration of observations from ground-based radio telescopes and space-based X-ray observatories, we are starting to figure FRBs out.

February 15, 2024February 15, 2024 by Nancy Atkinson

NASA is Trying to Fix a Problem With one of Perseverance's Instruments

NASA’s Perseverance puts its robotic arm to work around a rocky outcrop called “Skinner Ridge” in a set of images captured in June and July 2022 by the rover’s Mastcam-Z camera system. SHERLOC is mounted on the end of the arm. NASA/JPL-Caltech/ASU/MSSS

There’s a problem with the Perseverance rover. One of its instruments, the laser-shooting SHERLOC, which is mounted on the end of the robotic arm, has a dust cover that is supposed to protect the instrument when it’s not in use. Unfortunately, the cover has been stuck open, and that can allow dust to collect on the sensitive optics. The cover is partially open, so the rover can’t use its laser on rock targets or collect mineral spectroscopy data. NASA engineers are investigating the problem and are hoping to devise a solution.