Featured Archives

December 4, 2023December 4, 2023 by Matt Williams

How Can Astronauts Maintain Their Bodies With Minimal Equipment?

NASA astronauts Bob Hines and Kjell Lindgren work out on the Advanced Resistive Exercise Device (ARED). Credits: NASA

Decades of research aboard the International Space Station (ISS) and other spacecraft in Low Earth Orbit (LEO) have shown that long-duration stays in microgravity will take a toll on human physiology. Among the most notable effects are muscle atrophy and bone density loss and effects on eyesight, blood flow, and cardiovascular health. However, as research like NASA’s Twin Study showed, the effects extend to organ function, psychological effects, and gene expression. Mitigating these effects is vital for future missions to the Moon, Mars, and other deep-space destinations.

To reduce the impact of microgravity, astronauts aboard the ISS rely on a strict regiment of resistance training, proper diet, and cardiovascular exercise to engage their muscles, bones, and other connective tissues that comprise their musculoskeletal systems. Unfortunately, the machines aboard the ISS are too large and heavy to bring aboard spacecraft for long-duration spaceflights, where space and mass requirements are limited. To address this, NASA is investigating whether exercise regimens that rely on minimal or no equipment could provide adequate physical activity.

December 4, 2023December 4, 2023 by Matt Williams

Europa Clipper Could Help Discover if Jupiter's Moon is Habitable

Artist's concept of a Europa Clipper mission. Credit: NASA/JPL

Since 1979, when the Voyager probes flew past Jupiter and its system of moons, scientists have speculated about the possibility of life within Europa. Based on planetary modeling, Europa is believed to be differentiated between a rocky and metallic core, an icy crust and mantle, and a liquid-water ocean that could be 100 to 200 km (62 to 124 mi) deep. Scientists theorize that this ocean is maintained by tidal flexing, where interaction with Jupiter’s powerful gravitational field leads to geological activity in Europa’s core and hydrothermal vents at the core-mantle boundary.

Investigating the potential habitability of Europa is the main purpose of NASA’s Europa Clipper mission, which will launch on October 10th, 2024, and arrive around Jupiter in April 2030. However, this presents a challenge for astrobiologists since the habitability of Europa is dependent on many interrelated parameters that require collaborative investigation. In a recent paper, a team of NASA-led researchers reviewed the objectives of the Europa Clipper mission and anticipated what it could reveal regarding the moon’s interior, composition, and geology.

December 2, 2023December 2, 2023 by Matt Williams

Eris Could be Slushier Than Pluto

Artist’s impression shows the distant dwarf planet Eris. Credit: ESO

In 2005, astronomer Mike Brown and his colleagues Chad Trujillo and David Rabinowitz announced the discovery of a previously unknown planetoid in the Kuiper Belt beyond Neptune’s orbit. The team named this object Eris after the Greek personification of strife and discord, which was assigned by the IAU a year later. Along with Haumea and Makemake, which they similarly observed in 2004 and 2005 (respectively), this object led to the “Great Planet Debate,” which continues to this day. Meanwhile, astronomers have continued to study the Trans-Neptunian region to learn more about these objects.

While subsequent observations have allowed astronomers to get a better idea of Eris’ size and mass, there are many unresolved questions about the structure of this “dwarf planet” and how it compares to Pluto. In a recent study, Mike Brown and University of California Santa Cruz professor Francis Nimmo presented a series of models based on new mass estimates for Eris’ moon Dysnomia. According to their results, Eris is likely differentiated into a convecting icy shell and rocky core, which sets it apart from Pluto’s conductive shell.

November 30, 2023November 30, 2023 by Matt Williams

Fermi has Found More than 300 Gamma-Ray Pulsars

Visualization of a fast-rotating pulsar. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

In June 2008, the Gamma-ray Large Area Space Telescope began surveying the cosmos to study some of the most energetic phenomena in the Universe. Shortly after that, NASA renamed the observatory in the Fermi Gamma-ray Space Telescope in honor of Professor Enrico Fermi (1901-1954), a pioneer in high-energy physics. During its mission, Fermi has addressed questions regarding some of the most mysterious and energetic phenomena in the Universe – like gamma-ray bursts (GRBs), cosmic rays, and extremely dense stellar remnants like pulsars.

Since it began operations, Fermi has discovered more than 300 gamma-ray pulsars, which have provided new insights into the life cycle of stars, our galaxy, and the nature of the Universe. This week, a new catalog compiled by an international team contains the more than 300 pulsars discovered by the Fermi mission – which includes 294 confirmed gamma-ray-emitting pulsars and another 34 candidates awaiting confirmation. This is 27 times the number of pulsars known to astronomers before the Fermi mission launched in 2008.

November 29, 2023November 29, 2023 by Matt Williams

Odyssey Gives Us a Cool New View of Mars

This unusual view of the horizon of Mars was captured by NASA’s Odyssey orbiter using its THEMIS camera, in an operation that took engineers three months to plan. It’s taken from about 250 miles above the Martian surface – about the same altitude at which the International Space Station orbits Earth. NASA/JPL-Caltech/ASU

Chances are that you’ve seen images of Earth from space, thanks to the astronauts aboard the International Space Station (ISS), who regularly share stunning photos of our planet. These images provide us regularly with breathtaking views of cities, oceans, storms, eruptions, clouds, the curvature of the planet, and the way the atmosphere glows against the horizon. Thanks to NASA’s Mars Odyssey Orbiter, which has been in orbit for over 22 years, we now have an equally breathtaking view of Mars from orbit that captured what its curvature and atmosphere look like from space.

November 29, 2023December 5, 2023 by David Dickinson

The Solar Radius Might Be Slightly Smaller Than We Thought

SDO Sol — NASA SDO's view, of our tempestuous host star. NASA/SDO

A pioneering method suggests that the size of our Sun and the solar radius may be due revision.

Our host star is full of surprises. Studying our Sun is the most essential facet of modern astronomy: not only does Sol provide us with the only example of a star we can study up close, but the energy it provides fuels life on Earth, and the space weather it produces impacts our modern technological civilization.

Now, a new study, titled The Acoustic Size of the Sun suggests that a key parameter in modern astronomy and heliophysics—the diameter of the Sun—may need a slight tweak.

November 28, 2023November 28, 2023 by Matt Williams

Why Don't We See Robotic Civilizations Rapidly Expanding Across the Universe?

The central region of the Milky Way, also known as the Zone of Avoidance. Credit: ESO/S. Brunier

In 1950, while sitting down to lunch with colleagues at the Los Alamos Laboratory, famed physicist and nuclear scientist Enrico Fermi asked his famous question: “Where is Everybody?” In short, Fermi was addressing the all-important question that has plagued human minds since they first realized planet Earth was merely a speck in an infinite Universe. Given the size and age of the Universe and the way the ingredients for life are seemingly everywhere in abundance, why haven’t we found any evidence of intelligent life beyond Earth?

This question has spawned countless proposed resolutions since Fermi’s time, including the infamous Hart-Tipler Conjecture (i.e., they don’t exist). Other interpretations emphasize how space travel is hard and extremely time and energy-consuming, which is why species are likely to settle in clusters (rather than a galactic empire) and how we are more likely to find examples of their technology (probes and AI) rather than a species itself. In a recent study, mathematician Daniel Vallstrom examined how artificial intelligence might be similarly motivated to avoid spreading across the galaxy, thus explaining why we haven’t seen them either!

November 26, 2023November 26, 2023 by Matt Williams

Next Generation Space Telescopes Could Use Deformable Mirrors to Image Earth-Sized Worlds

The Roman Space Telescope Coronagraph during assembly of the static optics at NASA’s Jet Propulsion Laboratory Credits: Dr. Eduardo Bendek

Observing distant objects is no easy task, thanks to our planet’s thick and fluffy atmosphere. As light passes through the upper reaches of our atmosphere, it is refracted and distorted, making it much harder to discern objects at cosmological distances (billions of light years away) and small objects in adjacent star systems like exoplanets. For astronomers, there are only two ways to overcome this problem: send telescopes to space or equip telescopes with mirrors that can adjust to compensate for atmospheric distortion.

Since 1970, NASA and the ESA have launched more than 90 space telescopes into orbit, and 29 of these are still active, so it’s safe to say we’ve got that covered! But in the coming years, a growing number of ground-based telescopes will incorporate adaptive optics (AOs) that will allow them to perform cutting-edge astronomy. This includes the study of exoplanets, which next-generation telescopes will be able to observe directly using coronographs and self-adjusting mirrors. This will allow astronomers to obtain spectra directly from their atmospheres and characterize them to see if they are habitable.

November 25, 2023November 25, 2023 by Matt Williams

Ariane 6 Fires its Engines, Simulating a Flight to Space

The Ariane 6 rocket test firing on its launch pad at the European Spaceport in French Guiana. Credit: ESA

Since 2010, the European aerospace manufacturer ArianeGroup has been developing the Ariane 6 launch vehicle, a next-generation rocket for the European Space Agency (ESA). This vehicle will replace the older Ariane 5 model, offering reduced launch costs while increasing the number of launches per year. In recent years, the ArianeGrouip has been putting the rocket through its paces to prepare it for its first launch, which is currently scheduled for 2024. This past week, on Wednesday, November 23rd, the Ariane 6 underwent its biggest test to date as ground controllers conducted a full-scale dress rehearsal.

November 23, 2023November 23, 2023 by Matt Williams

NASA is Getting the Plutonium it Needs for Future Missions

Close-up of NASA’s Perseverance Mars rover as it looks back at its wheel tracks on March 17, 2022, the 381st Martian day, or sol, of the mission. Credit: NASA

Radioisotope Thermoelectric Generators (RTGs) have a long history of service in space exploration. Since the first was tested in space in 1961, RTGs have gone on to be used by 31 NASA missions, including the Apollo Lunar Surface Experiments Packages (ALSEPs) delivered by the Apollo astronauts to the lunar surface. RTGs have also powered the Viking 1 and 2 missions to Mars, the Ulysses mission to the Sun, Galileo mission to Jupiter, and the Pioneer, Voyager, and New Horizons missions to the outer Solar System – which are currently in (or well on their way to) interstellar space.

In recent years, RTGs have allowed the Curiosity and Perseverance rovers to continue the search for evidence of past (and maybe present) life on Mars. In the coming years, these nuclear batteries will power more astrobiology missions, like the Dragonfly mission that will explore Saturn’s largest moon, Titan. In recent years, there has been concern that NASA was running low on Plutonium-238, the key component for RTGs. Luckily, the U.S. Department of Energy (DOE) recently delivered a large shipment of plutonium oxide, putting it on track to realize its goal of regular production of the radioisotopic material.