Scott Alan Johnston, Author at Universe Today

September 1, 2024September 1, 2024 by Scott Alan Johnston

Gravitational Wave Observatories Could Detect Primordial Black Holes Speeding Through the Solar System

Artist illustration of primordial black holes. NASA's Goddard Space Flight Center

Cosmologists have long hypothesized that the conditions of the early universe could have caused the formation of black holes not long after the Big Bang. These ‘primordial black holes’ have a much wider mass range than those that formed in the later universe from the death of stars, with some even condensed to the width of a single atom.

July 2, 2024July 2, 2024 by Scott Alan Johnston

Plate Tectonics Might Only Occur on 0.003% of Planets. That Makes Earth Very Special Indeed.

Plate tectonics: Image Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio

Plate tectonics, oceans, and continents might just be the secret ingredients for complex life on Earth. And if these geological features are rare elsewhere in the universe, then perhaps that explains why we haven’t yet discovered intelligent alien life. New research from American and Swiss Earth scientists suggests that these ingredients represent missing variables in the famous Drake equation, devised more than half a century ago to estimate the chances of finding advanced civilizations in our galaxy. Including these new variables could completely rewrite the probability of detecting intelligent life in the Milky Way.

June 14, 2024June 14, 2024 by Scott Alan Johnston

Webb is an Amazing Supernova Hunter

80 objects (circled in green) that changed in brightness over time, as seen by JWST. Most of these are supernovae. NASA, ESA, CSA, STScI, JADES Collaboration

The James Webb Space Telescope (JWST) has just increased the number of known distant supernovae by tenfold. This rapid expansion of astronomers’ catalog of supernovae is extremely valuable, not least because it improves the reliability of measurements for the expansion of the universe.

June 9, 2024June 9, 2024 by Scott Alan Johnston

Carbon is Surprisingly Abundant in an Early Galaxy

Deep field image from JWST Credit: NASA, ESA, CSA, STScI, Brant Robertson (UC Santa Cruz), Ben Johnson (CfA), Sandro Tacchella (Cambridge), Phill Cargile (CfA)

The James Webb Space Telescope (JWST) has once again found evidence that the early universe was a far more complex place than we thought. This time, it has detected the signature of carbon atoms present in a galaxy that formed just 350 million years after the Big Bang – one of the earliest galaxies ever observed.

June 4, 2024June 4, 2024 by Scott Alan Johnston

Hubble Pauses its Science Again

This image of NASA's Hubble Space Telescope was taken on May 19, 2009 after deployment during Servicing Mission 4. NASA

The Hubble Space Telescope has been shut down temporarily after one of its gyroscopes sent faulty telemetry readings back to Earth in late May. The venerable space-based observatory, which has been responsible for some of the most remarkable scientific advances of the last three decades, and stunning astrophotography that became a cultural mainstay, is in its thirty-fourth year of operation.

May 24, 2024May 24, 2024 by Scott Alan Johnston

Fish are Adapting to Weightlessness on the Chinese Space Station

A female specimen of a zebrafish (Danio rerio). Azul, Wikimedia Commons.

Four zebrafish are alive and well after nearly a month in space aboard China’s Tiangong space station. As part of an experiment testing the development of vertebrates in microgravity, the fish live and swim within a small habitat aboard the station.

May 24, 2024May 24, 2024 by Scott Alan Johnston

NASA is Practicing for the Moon With Partial Space Suits

NASA astronauts Kate Rubins and Andre Douglas push a tool cart loaded with lunar tools through the San Francisco Volcanic Field north of Flagstaff, Arizona, as they practice moonwalking operations for Artemis III. NASA/Josh Valcarcel

In just a few short years, NASA hopes to put humans back on the lunar surface. The first moonwalk in more than 50 years is scheduled for no earlier than September 2026 as part of the Artemis III mission. In preparation, astronauts, scientists, and flight controllers are conducting simulated spacewalks here on Earth.

May 12, 2024May 12, 2024 by Scott Alan Johnston

Do Clashing Galaxies Create Odd Radio Circles?

This multiwavelength image of the Cloverleaf ORC (odd radio circle) combines visible light observations from the DESI (Dark Energy Spectroscopic Instrument) Legacy Survey in white and yellow, X-rays from XMM-Newton in blue, and radio from ASKAP (the Australian Square Kilometer Array Pathfinder) in red. X. Zhang and M. Kluge (MPE), B. Koribalski (CSIRO)

Within the last five years, astronomers have discovered a new type of astronomical phenomenon that exists on vast scales – larger than whole galaxies. They’re called ORCs (odd radio circles), and they look like giant rings of radio waves expanding outwards like a shockwave. Until now, ORCs had never been observed in any wavelength other than radio, but according to a new paper released on April 30 2024, astronomers have captured X-rays associated with an ORC for the first time.

April 18, 2024April 18, 2024 by Scott Alan Johnston

The Mystery of Cosmic Rays Deepens

The Fred Lawrence Whipple Observatory’s 48-inch telescope captured this visible-light image of the Pinwheel galaxy (Messier 101) in June 2023. The location of supernova 2023ixf is circled. The observatory, located on Mount Hopkins in Arizona, is operated by the Center for Astrophysics | Harvard & Smithsonian. Hiramatsu et al. 2023/Sebastian Gomez (STScI)

Cosmic rays are high-energy particles accelerated to extreme velocities approaching the speed of light. It takes an extremely powerful event to send these bits of matter blazing through the Universe. Astronomers theorize that cosmic rays are ejected by supernova explosions that mark the death of supergiant stars. But recent data collected by the Fermi Gamma-ray space telescope casts doubt on this production method for cosmic rays, and has astronomers digging for an explanation.

April 4, 2024April 4, 2024 by Scott Alan Johnston

The Moon Will Get its Own Time Zone

Gravitational Wave science holds great potential that scientists are eager to develop. Is a gravitational wave observatory on the Moon the way forward? NASA/Goddard/LRO.

White House officials have directed NASA to begin work on establishing a standard time for the Moon, according to a report from Reuters this week. Coordinated Lunar Time (LTC) is intended to help ensure synchronization between the various lunar activities planned under the Artemis program.