Earth Archives

November 13, 2024November 13, 2024 by Matt Williams

New Study Examines How Extraterrestrial Civilizations Could Become “Stellarvores.”

Artist's impression of accretion in a binary system. Credit: ESO/L. Calçada

One of the most challenging aspects of astrobiology and the Search for Extraterrestrial Intelligence (SETI) is anticipating what life and extraterrestrial civilizations will look like. Invariably, we have only one example of a planet that supports life (Earth) and one example of a technologically advanced civilization (humanity) upon which to base our theories. As for more advanced civilizations, which statistically seems more likely, scientists are limited to projections of our own development. However, these same projections offer constraints on what SETI researchers should search for and provide hints about our future development.

In a series of papers led by the Blue Marble Space Institute of Science (BMSIS), a team of researchers examines what Earth’s level of technological development (aka. “technosphere”) will look like in the future. In the most recent installment, they offer a reinterpretation of the Kardashev Scale, which suggests that civilizations expand to harness greater levels of energy (planet, host star, and galaxy). Instead, they suggest that the Kardashev Scale establishes upper limits on the amount of stellar energy a civilization can harness (a “luminosity limit”) and that civilizations might circumvent this by harnessing stellar mass directly.

November 11, 2024November 12, 2024 by Matt Williams

Project Hyperion is Seeking Ideas for Building Humanity’s First Generation Ship

Project Hyperion is the first design competition for a generation ship. Credit: Maciej Rebisz/Michel Lamontagne

The dream of traversing the depths of space and planting the seed of human civilization on another planet has existed for generations. For long as we’ve known that most stars in the Universe are likely to have their own system of planets, there have been those who advocated that we explore them (and even settle on them). With the dawn of the Space Age, this idea was no longer just the stuff of science fiction and became a matter of scientific study. Unfortunately, the challenges of venturing beyond Earth and reaching another star system are myriad.

When it comes down to it, there are only two ways to send crewed missions to exoplanets. The first is to develop advanced propulsion systems that can achieve relativistic speeds (a fraction of the speed of light). The second involves building spacecraft that can sustain crews for generations – aka. a Generation Ship (or Worldship). On November 1st, 2024, Project Hyperion launched a design competition for crewed interstellar travel via generation ships that would rely on current and near-future technologies. The competition is open to the public and will award a total of $10,000 (USD) for innovative concepts.

November 3, 2024November 3, 2024 by Matt Williams

Plastic Waste on our Beaches Now Visible from Space, Says New Study

Yellow spot indicating plastic on the blue satellite image of an otherwise pristine beach. Credit: RMIT

According to the United Nations, the world produces about 430 million metric tons (267 U.S. tons) of plastic annually, two-thirds of which are only used for a short time and quickly become garbage. What’s more, plastics are the most harmful and persistent fraction of marine litter, accounting for at least 85% of total marine waste. This problem is easily recognizable due to the Great Pacific Garbage Patch and the amount of plastic waste that washes up on beaches and shores every year. Unless measures are taken to address this problem, the annual flow of plastic into the ocean could triple by 2040.

One way to address this problem is to improve the global tracking of plastic waste using Earth observation satellites. In a recent study, a team of Australian researchers developed a new method for spotting plastic rubbish on our beaches, which they successfully field-tested on a remote stretch of coastline. This satellite imagery tool distinguishes between sand, water, and plastics based on how they reflect light differently. It can detect plastics on shorelines from an altitude of more than 600 km (~375 mi) – higher than the International Space Station‘s (ISS) orbit.

October 28, 2024October 28, 2024 by Mark Thompson

Astronauts Could Take an Asteroid Ferry from Earth to Mars

This idea really is quite a fascinating one. Currently a trip to Mars would require large amounts of air, water and other resources to sustain human life but would also expose travellers to harmful levels of radiation. A wonderful solution has been proposed in a new paper recently published by researchers from Ukraine. They propose that asteroids which already travel relatively close by Earth, Mars and even Venus already could be used to hop between the planets. They are already making the journey anyway and so perhaps the cosmos already provides the solution to interplanetary travel.

October 17, 2024October 19, 2024 by Matt Williams

Establishing a New Habitability Metric for Future Astrobiology Surveys

An illustration of the variations among the more than 5,000 known exoplanets discovered since the 1990s. Could their stars' metallicity play a role in making them habitable to life? Credit: NASA/JPL-Caltech

The search for exoplanets has grown immensely in recent decades thanks to next-generation observatories and instruments. The current census is 5,766 confirmed exoplanets in 4,310 systems, with thousands more awaiting confirmation. With so many planets available for study, exoplanet studies and astrobiology are transitioning from the discovery process to characterization. Essentially, this means that astronomers are reaching the point where they can directly image exoplanets and determine the chemical composition of their atmospheres.

As always, the ultimate goal is to find terrestrial (rocky) exoplanets that are “habitable,” meaning they could support life. However, our notions of habitability have been primarily focused on comparisons to modern-day Earth (i.e., “Earth-like“), which has come to be challenged in recent years. In a recent study, a team of astrobiologists considered how Earth has changed over time, giving rise to different biosignatures. Their findings could inform future exoplanet searches using next-generation telescopes like the Habitable Worlds Observatory (HWO), destined for space by the 2040s.

October 15, 2024October 15, 2024 by Matt Williams

China Releases its First Roadmap for Space Science and Exploration Through 2050.

China has released its first national plan for space 2024 and 2050. Credit: CFP

China’s space program has advanced considerably since the turn of the century. In addition to developing heavy-launch vehicles like the Long March 5 and building a modular space station in orbit, China has also embarked on an ambitious program of lunar exploration (Chang’e) – which has launched six robotic missions to explore the Moon’s surface since 2007. These missions are paving the way for crewed missions to the Moon by 2030 and creating a permanent habitat around the Moon’s southern polar region – the International Lunar Research Station (ILRS).

They also plan to send crewed missions to Mars by 2033, which will culminate in the creation of a permanent base there too. Earlier today, the Chinese Academy of Sciences (CAS), the China National Space Administration (CNSA), and the China Manned Space Agency (CMSE) jointly released the country’s first long-term scheme for space science and exploration. Titled “National Medium—and Long-Term Development Plan for Space Science (2024-2050),” this plan elaborated on the basic principles, development goals, and roadmap for the country’s space science and exploration through 2050.

September 19, 2024September 19, 2024 by Matt Williams

The Polaris Dawn Crew is Back on Earth

The Polaris Dawn crew (left to right): Anna Menon, Scott Poteet, Jared Isaacman, and Sarah Gillis. Credit: Polaris Program/John Kraus

On September 15th, 2024, the Polaris Dawn crew returned to Earth after spending five days in orbit. The mission was the first of three planned for the Polaris program, a private space project to advance human spaceflight capabilities and raise funds and awareness for charitable causes. The mission’s Dragon spacecraft safely splashed down off the coast of Florida at 3:36:54 a.m. EDT (12:36:54 p.m. PDT). Once their spacecraft was retrieved, the crew was flown to the Kennedy Space Center to see their families and undergo medical examinations before traveling to Houston to complete more of the mission’s studies.

September 4, 2024September 4, 2024 by Matt Williams

A Review of Humanity’s Planned Expansion Between the Earth and the Moon

Artist's impression of astronauts on the lunar surface, as part of the Artemis Program. Credit: NASA

Between Low Earth Orbit (LEO) and the Moon, there is a region of space measuring 384,400 km (238,855 mi) wide known as Cislunar space. In the coming decades, multiple space agencies will send missions to this region to support the development of infrastructure that will lead to a permanent human presence on the Moon. This includes orbital and surface habitats, landing pads, surface vehicles, technologies for in-situ resource utilization (ISRU), and other elements that will enable the long-term exploration and development of the lunar surface.

For all parties concerned, Cislunar space holds immense potential in terms of scientific, commercial, and military applications. The vastly increased level of activity on and around the Moon makes space domain awareness (SDA) – knowledge of all operations within a region of space – paramount. It is also necessary to ensure the continued success and utilization of the covered region. In a recent paper, a team of aerospace engineers considered the missions planned for the coming decades and evaluated the state and shortcomings of their space domain awareness.

September 3, 2024September 3, 2024 by Matt Williams

There Was a Strange Sound Coming From Starliner. It Was Caused by a Speaker in the Capsule

The Starliner spacecraft is pictured docked with the Harmony module at the International Space Station high above the Mediterranean Sea. Credit: NASA

As part of the Commercial Crew Program (CCP), NASA contracted with commercial space partners to develop crew-capable spacecraft to restore domestic launch capability to U.S. soil. In addition to SpaceX’s Crew Dragon vehicle, which was validated in 2020 and has been transporting crews to the International Space Station (ISS) ever since. Concurrently, Boeing developed the CT-100 Starliner, which has suffered a seemingly endless string of technical issues and delays. After undergoing a long checklist of fixes, the Starliner completed its first orbital flight test (OFT-1) in May 2022.

The Starliner then made its first crewed flight to the ISS on June 5th, 2024, carrying two astronauts – Butch Wilmore and Sunita Williams. Unfortunately, malfunctions with the spacecraft’s RCS thrusters have forced it to remain in orbit until the necessary fixes were made. In addition to its thrusters, astronaut Butch Wilmore identified a strange pulsing sound coming from the Starliner crew capsule. That sound has since been identified as feedback from one of the capsule’s speakers, apparently due to an audio configuration between the ISS and Starliner.

August 13, 2024August 13, 2024 by Matt Williams

NASA’s Says Goodbye to its Asteroid-Hunting NEOWISE Mission

NASA’s Wide-field Infrared Survey Explorer (WISE), launched in 2009, spent the next fourteen and half years studying the Universe in infrared wavelengths. During that time, it discovered thousands of minor planets, star clusters, and the first Brown Dwarf and Earth-Trojan asteroid. By 2013, the mission was reactivated by NASA as the Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE), which was tasked with searching for Potentially Hazardous Asteroids (PHAs). For ten years, the NEOWISE mission faithfully cataloged comets and asteroids that could pose a threat to Earth someday.

Unfortunately, NASA announced on July 1st that it would be decommissioning this planetary defense mission, which is expected to burn up in our atmosphere later this year. On Thursday, August 8th, the mission was decommissioned after the final command was sent from NASA’s Jet Propulsion Laboratory in Southern California and related to the spacecraft by the Tracking and Data Relay Satellite (TDRS) system. However, the scientific data NEOWISE collected during its ten years of operation will continue to inspire new discoveries!