Matt Williams, Author at Universe Today

September 14, 2023September 17, 2023 by Matt Williams

Some Lunar Regolith is Better for Living Off the Land on the Moon

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

Between now and the mid-2030s, multiple space agencies hope to send crewed missions to the Moon. of These plans all involve establishing bases around the Moon’s southern polar region, including the Artemis Base Camp and the International Lunar Research Station (ILRS). These facilities will enable a “sustained program of lunar exploration and development,” according to the NASA Artemis Program mission statement. In all cases, plans for building facilities on the surface call for a process known as In-Situ Resource Utilization (ISRU), where local resources are used as building materials.

This presents a bit of a problem since not all lunar soil (regolith) is well-suited for construction. Much like engineering and construction projects here on Earth, builders need to know what type of soil they are building on and if it can be used to make concrete. In a recent study, planetary scientist Kevin M. Cannon proposed a lunar soil classification scheme for space resource utilization. This could have significant implications for future missions to the Moon, where it would help inform the construction of bases, habitats, and other facilities based on soil type and location.

September 13, 2023September 13, 2023 by Matt Williams

Whether Saturn's Rings are Young or Old, its Moons are as Ancient as the Planet Itself

The moons of Saturn, from left to right: Mimas, Enceladus, Tethys, Dione, Rhea; Titan in the background; Iapetus (top) and irregularly shaped Hyperion (bottom). Some small moons are also shown. All to scale. Credit: NASA/JPL/Space Science Institute

Saturn is best known for two things: its iconic ring structures and its large system of natural satellites. Currently, 146 moons and moonlets have been discovered orbiting the ringed giant, 24 of which are regular satellites. These include the seven largest moons, Titan, Rhea, Iapetus, Dione, Tethys, Enceladus, and Mimas, which are icy bodies believed to have interior oceans. In addition, there are unresolved questions about the age of these satellites, with some suspecting that they formed more recently (like Saturn’s rings, which are a few hundred million years old).

To address these questions, an international team of astronomers created a series of high-resolution simulations coupled with improved estimates of Trans-Neptunian Object (TNO) populations. This allowed them to construct a chronology of impacts for Saturn’s most heavily cratered regular satellites – Mimas, Enceladus, Tethys, Dione, and Rhea. This established age limits of 4.1 and 4.4 billion years for all five, with the two innermost moons appearing more youthful than the outer three. These results could have significant implications for our understanding of the formation and tidal evolution of moons in the outer Solar System.

September 10, 2023September 10, 2023 by Matt Williams

Polaris is the Closest, Brightest Cepheid Variable. Very Recently, Something Changed.

View from within the Polaris triple star system; artist's rendering. The North Star is labeled Polaris A. Credit: NASA/ESA/HST, G. Bacon (STScI)

When you look up in the night sky and find your way to the North Star, you are looking at Polaris. Not only is it the brightest star in the Ursa Minor constellation (the Little Dipper), but its position relative to the north celestial pole (less than 1° away) makes it useful for orienteering and navigation. Since the age of modern astronomy, scientists have understood that the star is a binary system consisting of an F-type yellow supergiant (Polaris Aa) and a smaller main-sequence yellow dwarf (Polaris B). Further observations revealed that Polaris Aa is a classic Cepheid variable, a stellar class that pulses regularly.

For most of the 20th century, records indicate that the pulsation period has been increasing while the pulsation amplitude has been declining. But recently, this changed as the pulsation period started getting shorter while the amplitude of the velocity variations stopped increasing. According to a new study by Guillermo Torres, an astronomer with the Harvard & Smithsonian Center for Astrophysics (CfA), these behaviors could be attributed to long-term changes related to the binary nature of the system, where the two stars get closer to each other, and the secondary perturbs the atmosphere of the primary.

September 9, 2023September 9, 2023 by Matt Williams

Every Night and Every Morning, the Moon Rumbles With Tiny Quakes

Artist's impression of astronauts on the lunar surface, as part of the Artemis Program. How will they store power on the Moon? 3D printed batteries could help. Credit: NASA

The Moon was geologically active between 3.7 and 2.5 billion years ago, experiencing quakes, volcanic eruptions, and outgassing. Thanks to the Moon being an airless body, evidence of this past has been carefully preserved in the form of extinct volcanoes, lava tubes, and other features. While the Moon has been geologically inert for billions of years, it still experiences small seismic events due to tidal flexing (because of Earth’s gravitational pull) and temperature variations. These latter events happen regularly and are known as “moonquakes.”

Thanks to the Apollo missions, scientists have measured this activity using seismometers placed on the surface. In a recent NASA-funded study, a team of researchers from the California Institute of Technology (Caltech) reexamined the seismic data with a machine-learning model. This revealed that moonquakes occur with precise regularity, coinciding with the Sun rising to its peak position in the sky and then slowly setting. In this respect, moonquakes are like a “Lunar Alarm Clock,” which could be useful for future missions and lunar settlers!

September 7, 2023September 7, 2023 by Matt Williams

Another New Way to Measure Distance in the Universe: Baryon Acoustic Oscillations

An artist's concept of the latest, highly accurate measurement of the Universe from BOSS. The spheres show the current size of the "baryon acoustic oscillations" (BAOs) from the early universe, which have helped to set the distribution of galaxies that we see in the universe today. Galaxies have a slight tendency to align along the edges of the spheres — the alignment has been greatly exaggerated in this illustration. BAOs can be used as a "standard ruler" (white line) to measure the distances to all the galaxies in the universe. Credit: Zosia Rostomian, Lawrence Berkeley National Laboratory

Measuring cosmic distances is a major challenge thanks to the fact that we live in a relativistic Universe. When astronomers observe distant objects, they are not just looking through space but also back in time. In addition, the cosmos has been expanding ever since it was born in the Big Bang, and that expansion is accelerating. Astronomers typically rely on one of two methods to measure cosmic distances (known as the Cosmic Distance Ladder). On the one hand, astronomers rely on redshift measurements of the Cosmic Microwave Background (CMB) to determine cosmological distances.

Conversely, they will rely on local observations using parallax measurements, variable stars, and supernovae. Unfortunately, there is a discrepancy between redshift measurements of the CMB and local measurements, leading to what is known as the Hubble Tension. To address this, a team of astronomers from several Chinese universities and the University of Cordoba conducted a two-year statistical analysis of one million galaxies. From this, they’ve developed a new technique that relies on Baryon Acoustic Oscillations (BAO) to determine distances with a greater degree of precision.

September 6, 2023September 6, 2023 by Matt Williams

China Reveals Its Lunar Lander Design

Visualization of the ILRS, from the CNSA Guide to Partnership (June 2021). Credit: CNSA

Last May, as part of the nation’s growing presence in space, the China National Space Agency (CNSA) announced that it had established a Human Lunar Space Program that would send crewed missions to the Moon and culminate in the creation of a lunar base. This came shortly after China and Russia announced that they would be collaborating on future lunar missions, which included the creation of a base around the southern polar region. In June 2022, they announced that this base would be named the International Lunar Research Station (ILRS) and released a guide explaining how international partners could join.

On Thursday, August 31st, the China Manned Space Agency (CMSA) released artists’ renderings of their next-generation spacecraft and lunar lander. The spacecraft will consist of two sections, a reentry capsule, and a service section, while the lunar lander will include a landing section and a propulsion section. According to a statement released by the Agency, these vehicles will deliver crews to Low Earth Orbit (LEO) and allow China to send crewed missions to the lunar surface. The release of these images confirms what has been suspected for some time: that China fully intends to land taikonauts on the Moon before 2030.

September 6, 2023September 6, 2023 by Matt Williams

The Space Station is Getting Gigabit Internet

NASA's ILLUMA-T payload communicating with LCRD over laser signals. Credit: NASA/Dave Ryan

Aboard the International Space Station (ISS), astronauts and cosmonauts from many nations are performing vital research that will allow humans to live and work in space. For more than 20 years, the ISS has been a unique platform for conducting microgravity, biology, agriculture, and communications experiments. This includes the ISS broadband internet service, which transmits information at a rate of 600 megabits per second (Mbps) – ten times the global average for internet speeds!

In 2021, NASA’s Space Communications and Navigation (SCaN) began integrating a technology demonstrator aboard the ISS that will test optical (laser) communications and data transfer. This system currently consists of Laser Communications Relay Demonstration (LCRD) and will soon be upgraded with the addition of the Integrated LCRD Low Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T). Once complete, this system will be the first two-way, end-to-end laser relay system, giving the ISS a gigabit internet connection!

September 2, 2023September 2, 2023 by Matt Williams

Is Humanity Ready to Realize the Dream of Interstellar Travel?

The 8th Interstellar Symposium was held from July 10th to 13th at McGill University. Credit: Interstellar Research Group (IRG)

For generations, humans have dreamed, speculated, and theorized about the possibility of journeying to distant stars, finding habitable planets around them, and settling down. In time, the children of these bold adventurers would create a new civilization and perhaps even meet the children of Earth. People could eventually journey from one world to another, cultures would mix, and trade and exchanges would become a regular feature. The potential for growth that would come from these exchanges – intellectually, socially, politically, technologically, and economically – would be immeasurable.

Expanding humanity’s reach beyond the Solar System is not just the fevered dream of science fiction writers and futurists. It has also been the subject of very serious scientific research, and interest in the subject is again on the rise. Much like sending crewed missions to Mars, establishing permanent outposts on the Moon, and exploring beyond cislunar space with human astronauts instead of robots – there is a growing sense that interstellar travel could be within reach. But just how ready are we for this bold and adventurous prospect? Whether we are talking about probes vs. crews or technological vs. psychological readiness, is interstellar travel something we are ready to take on?

This was a central question raised at a public outreach event aptly named “Interstellar Travel: Are We Ready?” that took place at the 8th Interstellar Symposium: In Light of Other Suns, held from July 10th to 13th at the University of McGill in Montreal, Quebec. The symposium was hosted by the Interstellar Research Group (IRG), the International Academy of Astronautics (IAA), and Breakthrough Initiatives – in coordination with the University of McGill – and featured guest speakers and luminaries from multiple disciplines – ranging from astronomy and astrophysics to astrobiology, geology, and cosmology.

August 29, 2023August 29, 2023 by Matt Williams

JWST Plucks One Single Star out of a Galaxy Seen 12.5 Billion Years Ago

The massive gravity of galaxy cluster MACS0647 acts as a cosmic lens to bend and magnify light from the more distant MACS0647-JD system. Credit: NASA/ESA/CSA/STScI

After years of build-up and anticipation, the James Webb Space Telescope finally launched into orbit on December 25th, 2021 (what a Christmas present, huh?). Since then, the stunning images and data it has returned have proven beyond a doubt that it was the best Christmas present ever! After its first year of operations, the JWST has lived up to one of its primary objectives: to observe the first stars and galaxies that populated the Universe. The next-generation observatory has accomplished that by setting new distance records and revealing galaxies that existed less than 1 billion years after the Big Bang!

These studies are essential to charting the evolution of the cosmos and resolving issues with our cosmological models, like the Hubble Tension and the mysteries of Dark Matter and Dark Energy. Well, hang onto your hats because things have reached a new level of awesome! In a recent study, an international team of scientists isolated a well-magnified star candidate in a galaxy that appears as it was almost 12.5 billion years ago. The detection of a star that existed when the Universe was only ~1.2 billion years old showcases the abilities of the JWST and offers a preview of what’s to come!

August 25, 2023August 25, 2023 by Matt Williams

India's Rover Rolls Out Onto the Lunar Surface

The Indian Space Research Organisation (ISRO) successfully landed its Chandrayaan-3 Lander Module on the surface of the Moon on August 23, 2023. Credit: ISRO

On July 14th, 2023, the Indian Space Research Organization (ISRO) launched the third mission in its Chandrayaan (“Moon vehicle” in Hindi) lunar exploration program. Earlier this week (Wednesday, August 23rd), the Chandrayaan-3 mission’s Vikram lander touched down on the far side of the Moon, making India the fourth nation in the world to send missions to the lunar surface and the first to land one near the Moon’s south pole region. Shortly after that, the ISRO announced that they had deployed Pragyan, the rover element of the mission, to the surface.