Matt Williams, Author at Universe Today

June 22, 2020June 22, 2020 by Matt Williams

A New Search for Evidence of Technological Civilizations in the Milky Way

A team of astronomers from UCLA searched for "technosignatures" in the Kepler field data. Credit and Copyright: Danielle Futselaar

To date, astronomers have discovered 4,164 extrasolar planets in 3,085 star systems, with another 5,347 awaiting confirmation. With this many planets available for study, researchers have been able to apply new constraints on how likely habitable planets are. In fact, the latest estimates say there could be 6 billion in the Milky Way alone! Understandably, these discoveries have renewed interest in the Search for Extraterrestrial Intelligence (SETI).

But whereas the search for habitable planets is focused on finding evidence of biological processes (aka. “biosignatures”), SETI has historically been focused on evidence of technological activity – aka. “technosignatures.” With a grant from NASA, researchers from the Harvard-Smithsonian Center for Astrophysics (CfA) and the University of Rochester are gearing up for a new study that will look for different kinds of potential technosignatures.

June 21, 2020June 21, 2020 by Matt Williams

There are Features on Titan That Really Look Like Volcanic Craters

Doom Mons and Sotra Patera, apparent cryovolcanic features on Titan. Credit: NASA/JPL

On Sept. 15th, 2017, NASA’s Cassini Orbiter concluded its mission by diving into Saturn’s atmosphere. Over the course of the 13 years it spent studying the Saturn system, it revealed a great deal about this gas giant and its largest moon, Titan. In the coming years, scientists are eager to send another mission to Titan to follow up on Cassini and get a better look at its surface features, methane lakes, and other curious properties.

These include the morphological features in the northern polar region that are strikingly similar to volcanic features here on Earth. According to a recent study by the Planetary Science Institute (PSI), these features could be evidence of cryovolcanism that continues to this day. These findings are the latest evidence that Titan has an interior ocean and internal heating mechanisms, which could also mean the planet harbors life in his interior.

June 20, 2020June 20, 2020 by Matt Williams

Planets With Large Oceans are Probably Common in the Milky Way

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

Within our Solar Systems, there are several moons where astronomers believe life could be found. This includes Ceres, Callisto, Europa, Ganymede, Enceladus, Titan, and maybe Dione, Mimas, Triton, and the dwarf planet Pluto. These “ocean worlds” are believed to have abundant liquid water in their interiors, as well as organic molecules and tidal heating – the basic ingredients for life.

Which raises the all-important question: are similar moons to be found in other star systems? This is the question NASA planetary scientist Dr. Lynnae C. Quick and her team from NASA’s Goddard Space Flight Center sought to address. In a recent study, Quick and her colleagues examined a sample of exoplanet systems and found that ocean worlds are likely to be very common in our galaxy.

June 18, 2020June 18, 2020 by Matt Williams

ExoMars Sees the Martian Atmosphere Glowing Green

In the course of studying Mars, scientists have come to identify some key similarities to Earth’s own. One notable example is the way our atmospheres interact with sunlight to produce dazzling displays of energy. On Earth, these include not just the aurorae near the polar regions (Aurora Borealis and Australis), but the constant green glow that is the result of oxygen molecules interacting with sunlight (aka. “airglow”).

On Earth, airglow can be seen “edge-on” from space, as exemplified by the many spectacular images that are taken by astronauts aboard the International Space Station (ISS). This phenomenon was recently observed around Mars for the first time by the ESA’s Trace Gas Orbiter (TGO), which arrived at Mars in 2016 a part of the ExoMars program. Like aurorae, this observation is yet another example of how Mars is “Earth’s Twin.”

June 17, 2020June 17, 2020 by Matt Williams

Searching for the End of the Universe’s “Dark Age”

A ‘radio colour’ view of the sky above the Murchison Widefield Array radio telescope, part of the International Centre for Radio Astronomy Research (ICRAC). Credit: Radio image by Natasha Hurley-Walker (ICRAR/Curtin) and the GLEAM Team. MWA tile and landscape Credit: ICRAR/Dr John Goldsmith/Celestial Visions

According to the most widely accepted cosmological theories, the first stars in the Universe formed a few hundred million years after the Big Bang. Unfortunately, astronomers have been unable to “see” them since their emergence coincided during the cosmological period known as the “Dark Ages.” During this period, which ended about 13 billion years ago, clouds of gas filled the Universe that obscured visible and infrared light.

However, astronomers have learned that light from this era can be detected as faint radio signals. It’s for this reason that radio telescopes like the Murchison Widefield Array (MWA) were built. Using data obtained by this array last year, an international team of researchers is scouring the most precise radio data to date from the early Universe in an attempt to see exactly when the cosmic “Dark Ages” ended.

June 17, 2020June 17, 2020 by Matt Williams

What Does it Mean to Be a Space Architect?

Artist conception of a Hi-SEAS habitation dome. Credit: Blue Planet Research/Bryan Christie Design

Here on Earth, the concept of architecture (and those who specialize in it), is pretty clear and straightforward. But in space, human beings have comparatively little experience living and working in habitats. For the past sixty years, multiple space stations have been sent to Low Earth Orbit (LEO), which include the now-defunct Salyut stations, Skylab, and Mir, as well as the present-day International Space Station (ISS).

But in the near the future, we hope to build stations and commercial habitats in LEO, on the surface of the Moon, and Mars. In addition to needing a steady supply of food, water, and other necessities, measures will need to be taken to ensure the psychological well-being of their crews. In a recent article, Stellar Amenities founder and CEO (a space architect herself!) Anastasia Prosina explored how space architecture can meet these needs.

June 16, 2020June 16, 2020 by Matt Williams

Pulsars Confirm One of Einstein’s Best Ideas, That Freefall Really Feels Like You’re Experiencing a Lack of Gravity

This artist’s impression shows the exotic double object that consists of a tiny, but very heavy neutron star that spins 25 times each second, orbited every two and a half hours by a white dwarf star. The neutron star is a pulsar named PSR J0348+0432 that is giving off radio waves that can be picked up on Earth by radio telescopes. Although this unusual pair is very interesting in its own right it is also a unique laboratory for testing the limits of physical theories. This system is radiating gravitational radiation, ripples in spacetime. Although these waves cannot be yet detected directly by astronomers on Earth they can be detected indirectly by measuring the change in the orbit of the system as it loses energy. As the pulsar is so small the relative sizes of the two objects are not drawn to scale.

Six and a half decades after he passed away, famed theoretical physicist Albert Einstein is still being proven right! In addition to General Relativity (GR) being tested under the most extreme conditions, lesser-known aspects of his theories are still being validated as well. For example, GR predicts that gravity and inertia are often indistinguishable, in what is known as the gravitational Strong Equivalence Principle (SEP).

Thanks to an international team of researchers, it has been proven under the strongest conditions to date. By precisely tracking the motion of a pulsar, the team demonstrated that gravity causes neutron stars and white dwarf stars to fall with equal accelerations. This confirms Einstein’s prediction that freefall accurately simulates zero-gravity conditions in all inertial reference frames.

June 16, 2020June 16, 2020 by Matt Williams

Tiny Cubesat Detects an Exoplanet

In the past decade and a half, a total of 4,164 thousand planets have been discovered beyond our Solar System, while another 5220 await confirmation. The majority of these were detected by the venerable Kepler Space Telescope, while the remainder have been observed by the Transitting Exoplanet Survey Satellite (TESS) and a combination of other satellites and ground-based telescopes.

But in what is a new record, a known super-Earth was recently observed by the Arcsecond Space Telescope Enabling Research in Astrophysics (ASTERIA) small satellite – making it the smallest observatory to spot an exoplanet. Led by a team from the Massachusetts Institute of Technology (MIT), this mission has demonstrated that small satellites can perform complex tasks in space normally carried out by large observatories.

June 14, 2020November 11, 2020 by Matt Williams

New Horizons is so Far From Earth That the Positions of the Stars Look a Little Different From its Perspective

In July of 2015, the New Horizons spacecraft made history when it became the first robotic explorer to conduct a flyby of Pluto. This was followed by another first, when the NASA mission conducted the first flyby of a Kuiper Belt Object (KBO) on December 31st, 2018 – which has since been named Arrokoth. Now, on the edge of the Solar System, New Horizons is still yielding some groundbreaking views of the cosmos.

For example, we here on Earth are used to thinking that the positions of the stars are “fixed”. In a sense, they are, since their positions and motions are relatively uniform when seen from our perspective. But a recent experiment conducted by the New Horizons team shows how familiar stars like Proxima Centauri and Wolf 359 (two of the closest stars in our neighbors) look different when viewed from the edge of the Solar System.

June 12, 2020June 12, 2020 by Matt Williams

How SpaceX is Changing Starship to be Able to Land on the Moon

Artist concept of the SpaceX Starship on the surface of the Moon. Credits: SpaceX

In May of last year, NASA announced that it had selected 11 aerospace companies to study and produce prototypes for a Human Landing System (HLS). This decision was made as part of Project Artemis and NASA’s commitment to return humans to the Moon by 2024. A year later, the administration shared that they had narrowed the field down to three companies – SpaceX, Blue Origin, and relative newcomer Dynetics.

For their part, SpaceX is working on a modified version of the Starship, the commercial vehicle SpaceX is currently testing at Boca Chica. As an HLS, this spacecraft would be a fully reusable system, and also capable of integrating with the Orion spacecraft and the Lunar Gateway. According to recent statements Musk made on Twitter, the HLS version of the Starship will also have some interesting design features.