Matt Williams, Author at Universe Today

September 14, 2024September 14, 2024 by Matt Williams

New Video Shows How Tiny Spacecraft Will “Swarm” Proxima Centauri

Screenshot of the animation showing the Swarming Proxima Centauri approaching Proxima b. Credit: i4is/Interstellar Initiatives

Earlier this year, NASA selected a rather interesting proposal for Phase I development as part of their NASA Innovative Advanced Concepts (NIAC) program. It’s known as Swarming Proxima Centauri, a collaborative effort between Space Initiatives Inc. and the Initiative for Interstellar Studies (i4is) led by Space Initiative’s chief scientist, Marshall Eubanks. The concept was recently selected for Phase I development as part of this year’s NASA Innovative Advanced Concepts (NIAC) program.

Similar to other proposals involving gram-scale spacecraft and lightsails, the “swarming” concept involves accelerating tiny spacecraft with a laser array to up to 20% the speed of light. This past week, on the last day of the 2024 NASA Innovative Advanced Concepts (NIAC) Symposium, Eubanks and his colleagues presented an animation illustrating what this mission will look like. The video and their presentation provide tantalizing clues as to what scientists expect to find in the closest star system to our own. This includes Proxima b, the rocky planet that orbits within its parent star’s circumsolar habitable zone (CHZ).

September 13, 2024September 13, 2024 by Matt Williams

More Bodies Discovered in the Outer Solar System

The Subaru Telescope at the Mauna Kea Observatories, Hawaii. Credit: NAOJ

The outer Solar System has been a treasure trove of discoveries in recent decades. Using ground-based telescopes, astronomers have identified eight large bodies since 2002 – Quouar, Sedna, Orcus, Haumea, Salacia, Eris, Makemake, and Gonggang. These discoveries led to the “Great Planet Debate” and the designation “dwarf planet,” an issue that remains contentious today. On December 21st, 2018, the New Horizons mission made history when it became the first spacecraft to rendezvous with a Kuiper Belt Object (KBO) named Arrokoth – the Powhatan/Algonquin word for “sky.”

Since 2006, the Subaru Telescope at the Mauna Kea Observatory in Hawaii has been observing the outer Solar System to search for other KBOs the New Horizons mission could study someday. In that time, these observations have led to the discovery of 263 KBOs within the traditionally accepted boundaries of the Kuiper Belt. However, in a recent study, an international team of astronomers identified 11 new KBOs beyond the edge of what was thought to be the outer boundary of the Kuiper Belt. This discovery has profound implications for our understanding of the structure and evolution of the Solar System.

September 12, 2024September 12, 2024 by Matt Williams

See a First-Person View of the First Private Spacewalk

Spacecraft footage of Jared Isaacman conducting the first commercial EVA in spaceflight history. Credit: SpaceX

On Tuesday, September 10th, at 5:23 a.m. EST (03:23 p.m. PST), the Polaris Dawn mission launched from NASA’s Kennedy Space Center in Florida, carrying a crew of four to Low Earth Orbit (LEO). This mission is the first of three that comprise the Polaris Program, a private spaceflight program organized by entrepreneur and private astronaut Jared Isaacman and financed by SpaceX. Since launching, the Resilience Crew Dragon spacecraft has flown higher than any crewed mission since the Apollo Era and passed through parts of the Van Allen radiation belt.

Earlier today, the crew carried out the first private spacewalk in the history of spaceflight!

September 11, 2024September 11, 2024 by Matt Williams

Projecting what Earth will Look Like 1000 years from now Could Assist in the Search for Advanced Civilizations

Earth’s immature biosphere and mature biosphere stages. The mature biosphere stage was only possible once photosynthetic organisms created feedback with Earth’s non-biological processes, oxygenating the atmosphere and creating an ozone layer. Image Credit: University of Rochester illustration / Michael Osadciw

The Search for Extraterrestrial Intelligence (SETI) is regularly plagued by the fact that humanity has a very limited perspective on civilization and the nature of intelligence itself. When it comes right down to it, the only examples we have to go on are “life as we know it” (aka. Earth organisms) and human civilization. On top of that, given the age of the Universe and the time life has had to evolve on other planets, it is a foregone conclusion that any advanced life in our galaxy would be older than humanity. Luckily, this presents an opportunity to develop and test theoretical frameworks in the field.

To paraphrase Freeman Dyson, if we can conceive of a concept (and the physics are sound), an advanced species will likely have built it already. In this respect, imagining where humanity will be centuries or eons from now could provide potential “technosignatures” to look for. In a recent paper, a team from the Blue Marble Space Institute of Science (BMSIS) and NASA’s Goddard Space Flight Center modeled a series of scenarios that attempt to predict what humanity’s “technosphere” could look like 1,000 years from now. Their research could have implications for future SETI studies.

September 8, 2024September 8, 2024 by Matt Williams

ALMA Detects Hallmark “Wiggle” of Gravitational Instability in Planet-Forming Disk

ALMA images reveal vast spiral arms in the AB Aurigae circumstellar disk (three rightmost panels), and counterparts observed with VLT/SPHERE (leftmost panel). Credit: ALMA (ESO/NAOJ/NSF NRAO), VLT/SPHERE (ESO), Speedie et al.

According to Nebula Theory, stars and their systems of planets form when a massive cloud of gas and dust (a nebula) undergoes gravitational collapse at the center, forming a new star. The remaining material from the nebula then forms a disk around the star from which planets, moons, and other bodies will eventually accrete (a protoplanetary disk). This is how Earth and the many bodies that make up the Solar System came together roughly 4.5 billion years ago, eventually settling into their current orbits (after a few migrations and collisions).

However, there is still debate regarding certain details of the planet formation process. On the one hand, there are those who subscribe to the traditional “bottom-up” model, where dust grains gradually collect into larger and larger conglomerations over tens of millions of years. Conversely, you have the “top-down” model, where circumstellar disk material in spiral arms fragments due to gravitational instability. Using the Atacama Large Millimeter/submillimeter Array (ALMA), an international team of astronomers found evidence of the “top-down” model when observing a protoplanetary disk over 500 light-years away.

September 8, 2024September 8, 2024 by Matt Williams

Largest Dark Matter Detector is Narrowing Down Dark Matter Candidate

Technicians scanning for dust on the LUX-ZEPLIN (LZ) Dark Matter Detector. Credit: LZ Experiment

In 2012, two previous dark matter detection experiments—the Large Underground Xenon (LUX) and ZonEd Proportional scintillation in Liquid Noble gases (ZEPLIN)—came together to form the LUX-ZEPLIN (LZ) experiment. Since it commenced operations, this collaboration has conducted the most sensitive search ever mounted for Weakly Interacting Massive Particles (WIMPs) – one of the leading Dark Matter candidates. This collaboration includes around 250 scientists from 39 institutions in the U.S., U.K., Portugal, Switzerland, South Korea, and Australia.

On Monday, August 26th, the latest results from the LUX-ZEPLIN project were shared at two scientific conferences. These results were celebrated by scientists at the University of Albany‘s Department of Physics, including Associate Professors Cecilia Levy and Matthew Szydagis (two members of the experiment). This latest result is nearly five times more sensitive than the previous result and found no evidence of WIMPs above a mass of 9 GeV/c². These are the best-ever limits on WIMPS and a crucial step toward finding the mysterious invisible mass that makes up 85% of the Universe.

September 7, 2024September 7, 2024 by Matt Williams

Could Comets have Delivered the Building Blocks of Life to “Ocean Worlds” like Europa, Enceladus, and Titan too?

The "ocean worlds" of the Solar System. Credit: NASA/JPL

Throughout Earth’s history, the planet’s surface has been regularly impacted by comets, meteors, and the occasional large asteroid. While these events were often destructive, sometimes to the point of triggering a mass extinction, they may have also played an important role in the emergence of life on Earth. This is especially true of the Hadean Era (ca. 4.1 to 3.8 billion years ago) and the Late Heavy Bombardment, when Earth and other planets in the inner Solar System were impacted by a disproportionately high number of asteroids and comets.

These impactors are thought to have been how water was delivered to the inner Solar System and possibly the building blocks of life. But what of the many icy bodies in the outer Solar System, the natural satellites that orbit gas giants and have liquid water oceans in their interiors (i.e., Europa, Enceladus, Titan, and others)? According to a recent study led by researchers from Johns Hopkins University, impact events on these “Ocean Worlds” could have significantly contributed to surface and subsurface chemistry that could have led to the emergence of life.

September 5, 2024September 9, 2024 by Matt Williams

Ouch! A Monster Asteroid Crashed Into Ganymede 4 Billion Years Ago, Rolling it Over

Artist's impression of the large impact that caused Ganymede to reorient itself 4 billion years ago. © HIRATA Naoyuki

Jupiter’s moon, Ganymede, is a fascinating celestial body. Measuring 5,268 km (3,272 mi) in diameter, it is also the largest satellite in the Solar System and even larger than Mercury, which measures 4,880 km (3,032 mi) in diameter. Like Europa, it has an interior ocean and is one of the few bodies in the Solar System (other than the gas giants) with an intrinsic magnetic field. The presence of this field also means Ganymede experiences aurorae circling the regions around its northern and southern poles due to interaction with Jupiter’s magnetic field.

In addition, based on its surface craters, scientists believe that Ganymede experienced a powerful impact with an asteroid about 4 billion years ago. This asteroid was about 20 times larger than the Chicxulub asteroid that caused the extinction of the dinosaurs, or the Cretaceous–Paleogene extinction event (ca. 66 million years ago). According to a recent study by Naoyuki Hirata of Kobe University, this impact occurred almost precisely on the meridian farthest away from Jupiter. This caused a reorientation of Ganymede’s rotational axis and allowed Hirata to determine exactly what type of impact took place.

September 5, 2024September 5, 2024 by Matt Williams

There are Important Differences Between the Ice Caps on Mars

This image shows eroded channels near the Martian poles filled with bright frozen carbon dioxide, in contrast to the muted red of the underlying ground. Credit:NASA/JPL/University of Arizona

In the 17th century, astronomers Giovanni Domenica Cassini and Christian Huygens noted the presence of hazy white caps while studying the Martian polar regions. These findings confirmed that Mars had ice caps in both polar regions, similar to Earth. By the 18th century, astronomers began to notice how the size of these poles varied depending on where Mars was in its orbital cycle. Along with discovering that Mars’ axis was tilted like Earth’s, astronomers realized that Mars’ polar ice caps underwent seasonal changes, much like Earth’s.

While scientists have been aware that Mars’ polar ice caps change with the seasons, it has only been within the last 50 years that they have realized that they are largely composed of frozen carbon dioxide (aka. “dry ice”) that cycles in and out of the atmosphere – and questions as to how this happens remain. In a recent study, a team of researchers led by the Planetary Science Institute (PSI) synthesized decades of research with more recent observations of the poles. From this, they determined how the Martian poles differ in terms of their seasonal accumulation and release of atmospheric carbon dioxide.

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.