Universe Today

September 21, 2024September 21, 2024 by Matt Williams

Advanced Civilizations Will Overheat Their Planets Within 1,000 Years

Global temperature increases over the past thirty years, visualized. Credit: NOAA/NCEI

Earth’s average global temperatures have been steadily increasing since the Industrial Revolution. According to the National Oceanic and Atmospheric Agency (NOAA), Earth has been heating up at a rate of 0.06 °C (0.11 °F) per decade since 1850 – or about 1.11 °C (2 °F) in total. Since 1982, the average annual increase has been 0.20 °C (0.36 °F) per decade, more than three times as fast. What’s more, this trend is projected to increase by between 1.5 and 2 °C (2.7 to 3.6 °F) by mid-century, possibly more! This is a direct consequence of burning fossil fuels, which has increased exponentially since the mid-19th century.

Depending on the extent of temperature increases, the impact on Earth’s habitability could be catastrophic. In a recent study, a team of scientists examined how temperature increases are a long-term issue facing advanced civilizations and not just a matter of fossil fuel consumption. As they argue, rising planetary temperatures could be an inevitable result of the exponential growth of energy consumption. Their findings could have serious implications for astrobiology and the Search for Extraterrestrial Intelligence (SETI).

September 21, 2024September 21, 2024 by Mark Thompson

Astronomers Find the Longest Black Hole Jets Ever Seen

An artist's illustration of the longest black hole jet system ever observed.

Black holes often appear in science fiction movies, largely because elements of their existence are still a mystery. They have fascinating impacts on the surrounding region of space too with distortions in space and time high on the list. A team of astronomers have found a supermassive black hole with twin jets blasting out an incredible 23 million light years, the longest yet. To put this into context, if you lined up 140 Milky Way galaxies side by side, then that’s the length of the jet!

September 20, 2024September 20, 2024 by Mark Thompson

Second Generation Starlinks are 32 Times Brighter in Radio Wavelengths

Illustration Starlink satellites over LOFAR. Credit: Daniëlle Futselaar

Global internet access does seem like a worthy enterprise yet the rise of satellite megaconstellations there is a danger of the night sky becoming ruined. Astronomers the world over are keeping an eye on the impact these satellites are having on the night sky. Until recently the concerns have been relating to the reflection of visible light against the sky hindering night time observations. A recent study shows that the second-generation Starlink satellites leak 32 times the radio signal than the previous models. Are their presence putting at risk the radio sky now too?

September 20, 2024September 20, 2024 by Carolyn Collins Petersen

There’s Water All Over the Moon

Two images of the Moon from the Moon Mineralogy Mapper. The top is a black and white view of the north polar region while the bottom is a spectral map of water and hydroxyls seen in the south polar region. Credit: NASA/ISRO/M3 Team/PSI/R. Clark

When you look at the Moon, you don’t see any water on its surface. That doesn’t mean there isn’t any. In fact, there’s a lot of “wetness” on the Moon, but it’s in places and forms we can’t see. Understanding where all those resources are is the subject of a study based on NASA’s Moon Mineralogy Mapper (M3) data taken from aboard the Chandrayaan-1 spacecraft.

September 20, 2024September 20, 2024 by Evan Gough

Io’s Volcanoes are Windows into its Hot Interior

Juno captured this image of Io during Perijove 57. Data from Juno's JIRAM instrument is helping researchers understand how tidal heating shapes the moon's volcanic activity. Image Credit: NASA / SWRI / MSSS / Jason Perry © cc nc sa

NASA’s Juno spacecraft was sent to Jupiter to study the gas giant. But its mission was extended, giving it an opportunity to study the unique moon Io. Io is the most volcanically active body in the Solar System, with over 400 active volcanoes.

Researchers have taken advantage of Juno’s flybys of Io to study how tidal heating affects the moon.

September 20, 2024September 20, 2024 by Brian Koberlein

Could Stars Hotter Than the Sun Still Support Life?

A comparison of typical sizes of main sequence stellar classes. Credit: NASA’s Goddard Space Flight Center

Although most potentially habitable worlds orbit red dwarf stars, we know larger and brighter stars can harbor life. One yellow dwarf star, for example is known to have a planet teaming with life, perhaps even intelligent life. But how large and bright can a star be and still have an inhabited world? That is the question addressed in a recent article in the Astrophysical Journal.

September 19, 2024September 19, 2024 by Mark Thompson

Slime Mold Can Teach Us About the Cosmic Web

This image from Farhanul Hansan’s paper in the Astrophysical Journal shows the large-scale matter distribution and cosmic “filaments” of the universe are more faithfully captured by the slime mold model than the existing standard framework. (Image courtesy Farhanul Hasan)

Computers truly are wonderful things and powerful but only if they are programmed by a skilful mind. Check this out… there is an algorithm that mimics the growth of slim mold but a team of researchers have adapted it to model the large scale structure of the Universe. Since the Big Bang, the universe has been expanding while gravity concentrates matter into galaxies and clusters of galaxies. Between them are vast swathes of empty space called voids. The structure, often referred to as the cosmic web.

September 19, 2024September 25, 2024 by Evan Gough

Plants Would Still Grow Well Under Alien Skies

This is an artist's illustration of the rocky super Earth HD 219134. It orbits a K-type star, a long-lived stable type of main sequence star. The light from K-type stars is different than the Sun's. Can Earth plants photosynthesize effectively near these stars? Image Credit: By NASA/JPL-Caltech - http://photojournal.jpl.nasa.gov/jpeg/PIA19833.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=41995148

Photosynthesis changed Earth in powerful ways. When photosynthetic organisms appeared, it led to the Great Oxygenation Event. That allowed multicellular life to evolve and resulted in the ozone layer. Life could venture onto land, protected from the Sun’s intense ultraviolet radiation.

But Earth’s photosynthetic organisms evolved under the Sun’s specific illumination. How would plants do under other stars?

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 19, 2024September 19, 2024 by Mark Thompson

Building a Worldwide Map of Light Pollution

As someone that has always lived in the UK countryside I am no stranger to the glory of a dark star-filled sky. Sadly 60% of the world’s population has already lost access to the night sky thanks to light pollution. Across Europe and the US that number climbs to nearer 80%. A team of researchers want to try and track the growth of light pollution and to that end have developed an inexpensive sensor made from “off-the-shelf” parts. Their hope is that people around the world will build and install these sensors to share their data enabling them to track the spread of light pollution. If you’ve got technical skills, this could be a fun project.