Featured Archives

April 19, 2023April 19, 2023 by Matt Williams

The First Light in the Universe Helps Build a Dark Matter Map

A view of Stephan’s Quintet, a visual grouping of five galaxies from the James Webb Telescope. Credit: NASA/ESA/CSA/STScI

In the 1960s, astronomers began noticing a pervasive microwave background visible in all directions. Thereafter known as the Cosmic Microwave Background (CMB), the existence of this relic radiation confirmed the Big Bang theory, which posits that all matter was condensed onto a single point of infinite density and extreme heat that began expanding ca. 13.8 years ago. By measuring the CMB for redshift and comparing these to local distance measurements (using variable stars and supernovae), astronomers have sought to measure the rate at which the Universe is expanding.

Around the same time, scientists observed that the rotational curves of galaxies were much higher than their visible mass suggested. This meant that either Einstein’s Theory of General Relativity was wrong or the Universe was filled with a mysterious, invisible mass. In a new series of papers, members of the Atacama Cosmology Telescope (ACT) collaboration have used background light from the CMB to create a new map of Dark Matter distribution that covers a quarter of the sky and extends deep into the cosmos. This map confirms General Relativity and its predictions for how mass alters the curvature of spacetime.

April 18, 2023April 18, 2023 by Matt Williams

The Crab Nebula Looks Completely Different in X-Rays, Revealing its Magnetic Fields

Credits: Magnetic field lines: NASA/Bucciantini et al; X-ray: NASA/CXC/SAO; Optical: NASA/STScI; Infrared: NASA-JPL-Caltech

Located about 6,500 light-years away in the constellation Taurus resides one of the best-studied cosmological objects known as the Crab Nebula (aka. Messier 1). Originally discovered in the 18th century by English astronomer John Bevis in 1731, the Crab Nebula became the first object included by astronomer Charles Messier in his catalog of Deep Sky Objects. Because of its extreme nature, scientists have been studying the Crab Nebula for decades to learn more about its magnetic field, its high-energy emissions (x-rays), and how these accelerate particles to close to the speed of light.

Astronomers have been particularly interested in studying the polarization of the x-rays produced by the pulsar and what that can tell us about the nebula’s magnetic field. When studies were first conducted in the 1970s, astronomers had to rely on a sounding rocket to get above Earth’s atmosphere and measure the polarization using special sensors. Recently, an international team of astronomers used data obtained by NASA’s Imaging X-ray Polarimetry Explorer (IXPE) to create a detailed map of the Crab Nebula’s magnetic field that has resolved many long-standing mysteries about the object.

April 17, 2023April 17, 2023 by Matt Williams

How Many Intergalactic Radio Stations Are Out There?

The Stephans Quintet captured by the James Webb Space Telescope (JWST). Credit: NASA/ESA/CSA

It has been over sixty years since Dr. Frank Drake (father of the Drake Equation) and his colleagues mounted the first Search for Extraterrestrial Intelligence (SETI) survey. This was known as Project Ozma, which relied on the “Big Ear” radio telescope at the National Radio Astronomy Observatory (NRAO) in Greenbank, West Virginia, to look for signs of radio transmissions in Tau Ceti and Epsilon Eridani. Despite the many surveys conducted since then, no definitive evidence of technological activity (i.e., “technosignatures”) has been found.

This naturally raises the all-important question: are we going about the business of SETI wrong? Instead of looking for technosignatures within our galaxy, as all previous SETI surveys have done, should we look for activity beyond our galaxy (from possible Type II and Type III civilizations)? This premise was explored in a recent paper led by researchers from the National Chung Hsing University in Taiwan. Using data from the largest SETI project to date, Breakthrough Listen, the team looked for potential radio technosignatures from extragalactic sources.

April 14, 2023April 14, 2023 by Matt Williams

Twinkling Stars Supply the Dust That Leads to Life

Artist’s impression of the star in its multi-million year long and previously unobservable phase as a large, red supergiant. Credit: CAASTRO / Mats Björklund (Magipics)

When low to medium-mass stars exhaust their supply of hydrogen, they exit their main sequence phase and expand to become red giants – what is known as the Asymptotic Giant Branch (AGB) phase. Stars in this phase of their evolution become variable (experiences changes in brightness) to shed their outer lays, spreading dust throughout the interstellar medium (ISM) that is crucial to the development of planetary nebulas and protoplanetary systems. For decades, astronomers have sought to better understand the role Red Giant stars play.

Studying interstellar and protoplanetary dust is difficult because it is so faint in visible light. Luckily, this dust absorbs light and radiates brightly in the infrared (IR), making it visible to IR telescopes. Using archival data from now-retired Akari and Wide-field Infrared Survey Explorer (WISE) missions, a team of Japanese astronomers conducted the first long-period survey of dusty AGBs and observed that the variable intensity of these stars coincides with the amount of dust they produce. Since this dust plays an important role in the formation of planets, this study could shed light on the origins of life.

April 13, 2023April 13, 2023 by Matt Williams

What Can Be Done to Help Astronaut Vision in Space?

Astronauts Kate Rubins (left) and Jeff Williams (right) looking out of the ISS' cupola at a SpaceX Dragon supply spacecraft. Until recently, the effects of long-duration missions on eyesight was something of a mystery. Credit: NASA

Spaceflight takes a serious toll on the human body. As NASA’s Twin Study demonstrates, long-duration stays in space lead to muscle and bone density loss. There are also notable effects on the cardiovascular, central nervous, and endocrine systems, as well as changes in gene expression and cognitive function. There’s also visual impairment, known as Spaceflight-Associated Neuro-ocular Syndrome (SANS), which many astronauts reported after spending two months aboard the International Space Station (ISS). This results from increased intracranial pressure that places stress on the optic nerve and leads to temporary blindness.

Researchers are looking for ways to diagnose and treat these issues to prepare for future missions that will involve long-duration stays beyond Earth and transits in deep space. A cross-disciplinary team of researchers led by the University of Western Australia (UWA) has developed a breakthrough method for measuring brain fluid pressure that could reduce the risk of SANS for astronauts on long-duration spaceflights. This research could have applications for the many efforts to create a human presence on the Moon in this decade and crewed missions to Mars in the next.

April 11, 2023April 11, 2023 by Matt Williams

A New Membrane Could Lead to Space Telescopes with Flexible Mirrors!

Membrane mirrors made using the new technique are flexible enough to be rolled up. This could be helpful for storing the mirrors inside of a launch vehicle. © Sebastian Rabien, MPE

The James Webb Space Telescope (JWST) is the most powerful and sophisticated observatory ever built. It is also the most expensive, owing to the complexity of its design and the rigorous testing this entailed. To ensure the telescope could fit into its payload fairing, NASA engineers designed the JWST to fold up (origami-style) and unfold once it reached space. It is little wonder why astronomers and astrophysicists hope to develop flexible, lightweight materials that can maintain the perfect shape and be folded up to fit compactly inside a launch vehicle.

This has the potential to reduce the size and mass of space telescopes and the complexity of their designs, thus reducing launch costs. During the COVID pandemic, researchers at the Max Planck Institute for Extraterrestrial Physics (MPE) developed a new method for producing and shaping high-quality parabolic membrane mirrors. So far, the MPE team has fabricated prototypes up to 30 cm (12 inches) in diameter that are much thinner and more flexible than conventional mirrors. In the long term, this method could drastically reduce the cost of manufacturing and deploying space telescopes.

April 11, 2023April 11, 2023 by Matt Williams

Perseverance is Turning Into That Friend That's Always Picking Up Rocks

This image shows the rock core from “Berea” inside inside the drill of NASA’s Perseverance Mars rover. Credit: NASA/JPL-Caltech/ASU/MSSS

On Thursday, March 30th, NASA’s Perseverance rover drilled and stored the first rock core sample of its newest science campaign. This is the sixteenth sample the rover has taken as part of the ambitious Mars Sample Return (MSR) mission, a collaborative effort between NASA and the European Space Agency (ESA) to retrieve Perseverance’s samples and bring them back to Earth. Once they arrive (expected to happen by 2033), scientists will analyze them using state-of-the-art machinery too heavy and cumbersome to send to Mars as part of a robotic mission.

April 8, 2023April 8, 2023 by Matt Williams

Will the Starship be Ready for an April Launch?

The SN24 and BN7 fully stacked on the launch test pad at SpaceX's Starbase in Boca Chica, Texas. Credit: NASA

It’s been a long road, but it looks as though SpaceX may finally be ready for an orbital flight test with the Starship and Super Heavy. After months of waiting, static fire tests, stacking, and restacking, Elon Musk announced on March 16th that SpaceX could be ready to go with the SN24 and BN7 prototypes in “a few weeks,” pending approval from the Federal Aviation Administration (FAA). Musk announced via Twitter, saying, “launch timing depends on FAA license approval. Assuming that takes a few weeks, first launch attempt will be near end of third week of April, aka…”

April 5, 2023April 5, 2023 by Matt Williams

China Tests a Stirling Engine in Orbit

The uncapped Stirling thermoelectric converter. Credit: China Manned Space Agency

The China National Space Agency (CNSA) has made considerable progress in recent years with the development of its Long March 5 (CZ-5) rocket and the completion of its Tiangong-3 space station. The agency also turned heads when it announced plans in June 2021 to create an International Lunar Research Station (ILRS) that would rival the Artemis Program. On top of all that, China upped the ante when it announced later that month that it also had plans to send crewed missions to Mars by 2033, concurrent with NASA’s plans.

As part of their growing efforts to become a major power in space, which includes human exploration, China recently announced the completion of the first in-orbit test of a Stirling thermoelectric converter. The Shenzou-15 mission crew performed the test aboard Tiangong-3, and it was the first successful verification of the technology in space. This technology is also being investigated by NASA and is considered a technological solution to the challenges of space exploration, especially where long-duration stays and missions to locations in deep space are concerned.

April 5, 2023April 5, 2023 by Matt Williams

This JWST Image Shows Gravitational Lensing at its Finest

. Credit: ESA/Webb, NASA & CSA, J. Rigby

One of the more intriguing aspects of the cosmos, which the James Webb Space Telescope (JWST) has allowed astronomers to explore, is the phenomenon known as gravitational lenses. As Einstein’s Theory of General Relativity describes, the curvature of spacetime is altered by the presence of massive objects and their gravity. This effect leads to objects in space (like galaxies or galaxy clusters) altering the path light travels from more distant objects (and amplifying it as well). By taking advantage of this with a technique known as Gravitational Lensing, astronomers can study distant objects in greater detail.

Consider the image above, the ESA’s picture of the month acquired by the James Webb Space Telescope (JWST). The image shows a vast gravitational lens caused by SDSS J1226+2149, a galaxy cluster located roughly 6.3 billion light-years from Earth in the constellation Coma Berenices. The lens these galaxies created greatly amplified light from the more distant Cosmic Seahorse galaxy. Combined with Webb‘s incredible sensitivity, this technique allowed astronomers to study the Cosmic Seahorse in the hopes of learning more about star formation in early galaxies.