Evan Gough, Author at Universe Today

January 17, 2024January 17, 2024 by Evan Gough

Early Mars Climate was Complex, with Streams Flowing Intermittently for Millions of Years

This figure from new research shows an unnamed river valley network on Mars. By dating the craters in the image, a researcher at the Planetary Science Institute was able to determine when the river channels were formed. Image Credit: MOLA MEGDR, NASA/USGS; THEMIS mosaic, ASU/NASA/USGS; CTX, NASA/MSSS.

There’s overwhelming evidence that Mars was once wet and warm. Rivers flowed across its surface and carved intricate channel systems revealed by our orbiters. Expansive oceans even larger than Earth’s may have covered a third of its surface. Then something happened: Mars lost its atmosphere, cooled down, and surface water disappeared.

January 16, 2024January 16, 2024 by Evan Gough

NASA Confirms that 2023 was the Hottest Year on Record

This map of Earth in 2023 shows global surface temperature anomalies, or how much warmer or cooler each region of the planet was compared to the average from 1951 to 1980. Normal temperatures are shown in white, higher-than-normal temperatures in red and orange, and lower-than-normal temperatures in blue. Image Credit: NASA SVS

After analyzing the temperature data from 2023, NASA has concluded that it was the hottest year on record. This will surprise almost nobody. If you live in one of the regions stricken by drought, forest fires, or unusually powerful weather, you don’t need NASA to confirm that the planet is warming.

January 16, 2024January 16, 2024 by Evan Gough

Is K2-18b Covered in Oceans of Water or Oceans of Lava?

This illustration shows what exoplanet K2-18 b could look like based on science data. NASA’s James Webb Space Telescope examined the exoplanet and revealed the presence of carbon-bearing molecules. The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b. But more extensive observations with the JWST are needed to understand its atmosphere with greater confidence. Image Credit: By Illustration: NASA, ESA, CSA, Joseph Olmsted (STScI)Science: Nikku Madhusudhan (IoA)

In the search for potentially life-supporting exoplanets, liquid water is the key indicator. Life on Earth requires liquid water, and scientists strongly believe the same is true elsewhere. But from a great distance, it’s difficult to tell what worlds have oceans of water. Some of them can have lava oceans instead, and getting the two confused is a barrier to understanding exoplanets, water, and habitability more clearly.

January 15, 2024January 15, 2024 by Evan Gough

A Hot Jupiter With a Comet-Like Tail

The hot jupiter exoplanet WASP-69b orbits its star so closely that its atmosphere is being blown into space. Researchers made detailed observations of the planet, located about 160 light-years from Earth. They found that it has a comet-like tail extending about 560,000 km into space, about seven times the planet's diameter. Image Credit: Adam Makarenko/W. M. Keck Observatory

About 164 light-years away, a Hot Jupiter orbits its star so closely that it takes fewer than four days to complete an orbit. The planet is named WASP-69b, and it’s losing mass into space, stripped away by the star’s powerful energy. The planet’s lost atmosphere forms a trail that extends about 560,000 km (350,000 miles) into space.

January 13, 2024January 13, 2024 by Evan Gough

This Alien Landscape is Actually a Microscopic View of an Atomic Clock

This looks like the landscape feature called penitentes that form in the icy cold on Pluto. But it's actually a glass surface that's part of an atomic clock. Image Credit: Safran/ESA

Navigation satellites couldn’t accomplish anything without extremely accurate clocks. But a regular clock won’t do. Only atomic clocks are accurate enough, and that’s because they tell time with electrons.

Those atomic clocks wear out over time, and that’s what the image shows.

January 12, 2024January 12, 2024 by Evan Gough

Half of this Exoplanet is Covered in Lava

Like Kepler-10 b, illustrated above, the exoplanet HD 63433 d is a small, rocky planet in a tight orbit of its star. HD 63433 d is the smallest confirmed exoplanet younger than 500 million years old. It's also the closest discovered Earth-sized planet this young, at about 400 million years old. NASA/Ames/JPL-Caltech/T. Pyle

Astronomers working with TESS (Transiting Exoplanet Survey Satellite) have discovered a planet that’s been left out in the Sun too long. Or at least half of it has. The newly discovered planet is tidally locked to its star, and one side is completely molten.

January 11, 2024January 11, 2024 by Evan Gough

There are Mysteries at Venus. It’s Time for an Astrobiology Mission

NASA's Magellan spacecraft captured this image of Venusian craters. Image Credit: NASA/JPL

When scientists detected phosphine in Venus’ atmosphere in 2020, it triggered renewed, animated discussions about Venus and its potential habitability. It would be weird if the detection didn’t generate interest since phosphine is a potential biomarker. So people were understandably curious. Unfortunately, further study couldn’t confirm its presence.

But even without phosphine, Venus’ atmosphere is full of chemical intrigue that hints at biological processes. Is it time to send an astrobiology mission to our hellish sister planet?

January 11, 2024January 11, 2024 by Evan Gough

Planetesimals Are Buffeted by Wind in their Nebula, Throwing Debris into Space

This artist's illustration shows planetisimals around a young star. New research shows that planetesimals are blasted by headwind, losing debris into space. Image Credit: NASA/JPL

Before planets form around a young star, the protosolar disk is populated with innumerable planetesimals. Over time, these planetesimals combine to form planets, and the core accretion theory explains how that happens. But before there are planets, the disk full of planetesimals is a messy place.

January 10, 2024January 10, 2024 by Evan Gough

A Giant Star is Fading Away. But First, it Had an Enormous Eruption

Astronomers from Georgia State University’s CHARA Array have captured the first close-up images of a massive star known as RW Cephei that recently experienced a strange fading event. The images are providing new clues about what’s happening around the massive star approximately 16,000 light years from Earth. Image Credit: GSU/CHARA, Anugu et al. 2023

About 16,000 light-years away, a massive star experienced an unusual dimming event. This can happen in binary stars when one star passes in front of the other. It can also be due to intrinsic reasons like innate variability. But this star dimmed by as much as one-third, a huge amount.

What happened?

January 10, 2024January 10, 2024 by Evan Gough

The Youngest Planetary Disks Ever Seen

The evolutionary sequence of protoplanetary disks with substructures, from the ALMA CAMPOS survey. These wide varieties of planetary disk structures are possible formation sites for young protoplanets. Image Credit: Hsieh et al. in prep.

How long does planet formation take? Maybe not as long as we thought, according to new research. Observations with the Atacama Large Millimetre/submillimetre Array (ALMA) show that planet formation around young stars may begin much earlier than scientists thought.