Past Supernovae Could be Written Into Tree Rings

A bubble of gas expanding at roughly 11 million miles per hour created by the shockwave from a supernova. Credit: NASA

When stars reach the end of their lifespan, they undergo gravitational collapse at their cores. The type of explosion that results is one of the most awesome astronomical events imaginable and (on rare occasions) can even be seen with the naked eye. The last time this occurred was in 1604 when a Type Ia supernova took place over 20,000 light-years away – commonly-known as Kepler’s Supernova (aka. SN1604)

Given the massive amounts of radiation they release, past supernovae are believed to have played a role in the evolution of our planet and terrestrial life. According to new research by CU Boulder geoscientist Robert Brakenridge, these same supernovae may have left traces in our planet’s biology and geology. These findings could have implications given fears that Betelgeuse might be on the verge of going supernova.

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New Horizons Saw the Universe With Even Less Light Pollution than Hubble’s View

Artist's impression of New Horizons' close encounter with the Pluto–Charon system. Credit: NASA/JHU APL/SwRI/Steve Gribben

In July of 2015, NASA’s New Horizons probe made history when it became the first mission ever to conduct a close flyby of Pluto. This was followed by the spacecraft making the first-ever encounter with a Kuiper Belt Object (KBO) – known as Arrokoth (aka. 2014 MU69) – on Dec.31st, 2018. In addition, its unique position in the outer Solar System has allowed astronomers to conduct rare and lucrative science operations.

This has included parallax measurements of Proxima Centauri and Wolf 359, the two closest stars to the Solar System. In addition, a team of astronomers led by the National Optical Astronomy Observatory (NOAO) and Southwest Research Institute (SwRI) used archival data from the probe’s Long Range Reconnaissance Imager (LORRI) to conduct measurements of the Cosmic Optical Background (COB).

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SpaceX’s Resilience Spacecraft has Lifted Off and is Headed for the ISS!

The crew of the NASA/SpaceX Crew-1 flight. Credit: SpaceX

Earlier this evening (Sunday, November 15th, 2020), NASA and SpaceX achieved another historical milestone. Six months after successfully sending astronauts Robert Behnken and Douglas Hurley to the ISS with the Demo-2 mission, the US demonstrated the restoration of domestic launch capability by sending the fully-crewed Crew Dragon spacecraft (Resilience) on an operational mission to the ISS.

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What Role do Radioactive Elements Play in a Planet’s Habitability?

Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. Scientists could use this one or one like it to measure planetary entropy production as a prelude to exploration. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)
Illustration of Kepler-186f, a recently-discovered, possibly Earthlike exoplanet that could be a host to life. Scientists could use this one or one like it to measure planetary entropy production as a prelude to exploration. (NASA Ames, SETI Institute, JPL-Caltech, T. Pyle)

To date, astronomers have confirmed the existence of 4,301 extrasolar planets in 3,192 star systems, with another 5,650 candidates awaiting confirmation. In the coming years, next-generation telescopes will allow astronomers to directly observe many of these exoplanets and place tighter constraints on their potential habitability. In time, this could lead to the discovery of life beyond our Solar System!

The only problem is, finding evidence of life requires that we know what to look for. According to a new study by an interdisciplinary team of scientists from the University of California Santa Cruz (UCSC), radioactive elements might play a role in planetary habitability. Future studies of rocky exoplanets, they argue, should therefore look for specific isotopes that indicate the presence of long-lived elements like thorium and uranium.

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The Average Temperature of the Universe has Been Getting Hotter and Hotter

An illustration of cosmic expansion. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

For almost a century, astronomers have understood that the Universe is in a state of expansion. Since the 1990s, they have come to understand that as of four billion years ago, the rate of expansion has been speeding up. As this progresses, and the galaxy clusters and filaments of the Universe move farther apart, scientists theorize that the mean temperature of the Universe will gradually decline.

But according to new research led by the Center for Cosmology and AstroParticle Physics (CCAPP) at Ohio State University, it appears that the Universe is actually getting hotter as time goes on. After probing the thermal history of the Universe over the last 10 billion years, the team concluded that the mean temperature of cosmic gas has increased more than 10 times and reached about 2.2 million K (~2.2 °C; 4 million °F) today.

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Venus Held Onto its Water Surprisingly Well During its History

Artist's impression of Venus with the solar wind flowing around the planet, which has little magnetic protection. Venus Express found that a lot of water has bled into space over the years from the planet, which happens when the sun's ultraviolet radiation breaks oxygen and hydrogen molecules apart and pushes them into space. Credit: ESA - C. Carreau

Named for the ancient goddess of fertility, the planet Venus could not be more hostile to life as we know it. Aside from being the hottest planet in the Solar System, Venus has also an atmosphere that is 92 times denser than Earth’s, and regularly experiences sulfuric acid rain. But as we’ve learned from multiple surveys, Venus was once a much milder climate and even had vast oceans on its surface.

For astronomers and geologists alike, the burning question is, how much of its water did Venus hold onto during this massive transition? According to research presented by Moa Persson of the Swedish Institute of Space Physics (IRF), Venus actually retained most of its water over the past 4 billion years. Contrary to what researchers previously thought, Venus lost only a small amount of its water to a runaway Greenhouse Effect.

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Europa’s Nightside Glows in the Dark

This illustration of Jupiter's moon Europa shows how the icy surface may glow on its nightside, the side facing away from the Sun. Variations in the glow and the color of the glow itself could reveal information about the composition of ice on Europa's surface. Credit: NASA/JPL-Caltech

In a few years, NASA will be sending a spacecraft to explore Jupiter’s icy moon Europa. Known as the Europa Clipper mission, this orbiter will examine the surface more closely to search for plume activity and evidence of biosignatures. Such a find could answer the burning question of whether or not there is life within this moon, which is something scientists have speculated about since the 1970s.

In anticipation of this mission, scientists continue to anticipate what it will find once it gets there. For instance, scientists from NASA’s Jet Propulsion Laboratory recently conducted a study that showed how Europa might glow in the dark. This could be the result of Europa constantly being pummeled with high-energy radiation from Jupiter’s magnetic field, the study of which could tell scientists more about the composition of Europa’s ice.

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The Driest Place on Earth Could Help Predict How Life Might be Surviving on Mars

Future missions could determine the presence of past life on Mars by looking for signs of extreme metal-metabolizing bacteria. Credit: NASA.

In the next few years, Mars will be visited by three new rovers, the Perseverance, Tianwen-1, and Rosalind Franklin missions. Like their predecessors – Pathfinder and Sojourner, Spirit and Opportunity, and Curiosity – these robotic missions will explore the surface, searching for evidence of past and present life. But even after years of exploring, an important question remains: where is the best place to look?

To date, all attempts to find evidence of life on the surface have yielded nothing, owing to the fact that the Martian environment is extremely cold, desiccated, and irradiated. According to a new study by an international team of researchers led by Cornell University and the Centro de Astrobiología in Madrid, the Atacama desert in the mountains of Chile could hold the answer.

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One of the Terms of Service For Starlink is that You “Recognize Mars as a Free Planet”

Artist's illustration of a SpaceX Starship lands on Mars. Credit: SpaceX

In May of 2019, SpaceX began launching its Starlink constellation with the launch of its first 60 satellites. To date, the company has launched over 800 satellites and (as of this summer) is producing them at a rate of about 120 a month. By late 2021 or 2022, Elon Musk hopes to have a constellation of 1,440 satellites providing near-global service and perhaps as many as 42,000 providing internet to the entire planet before the decade is out.

As of November 2020, SpaceX has invited participants to take part in a public beta test called “Better Than Nothing.” The service, aptly named, is providing users with a modest rate of between 50 to 150 megabits per second, a far cry from the gigabit download speeds at low latency they hope to offer. But perhaps more interesting is the small item in the terms of service, where participants must acknowledge that Mars is a “free planet.”

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Lunar Dust is Still One of The Biggest Challenges Facing Moon Exploration

Apollo 17 astronaut Harrison Schmitt collecting a soil sample, his spacesuit coated with dust. Credit: NASA

In the coming years, astronauts will be returning to the Moon for the first time since the closing of the Apollo Era. Beyond that, NASA and other space agencies plan to establish the necessary infrastructure to maintain a human presence there. This will include the Artemis Gateway in orbit (formerly the Lunar Gateway) and bases on the surface, like NASA’s Artemis Base Camp and the ESA’s International Moon Village.

This presents a number of challenges. The Moon is an airless body, it experiences extreme variations in temperature, and its surface is exposed to far more radiation than we experience here on Earth. On top of that, there’s the lunar dust (aka. regolith), a fine powder that sticks to everything. To address this particular problem, a team of ESA-led researchers is developing materials that will provide better protection for lunar explorers.

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