Matt Williams is a space journalist and science communicator for Universe Today and Interesting Engineering. He's also a science fiction author, podcaster (Stories from Space), and Taekwon-Do instructor who lives on Vancouver Island with his wife and family.
There’s no way to sugarcoat it: Mars has a “dust problem.” The surface of the Red Planet is covered in particulate matter consisting of tiny bits of silica and oxidized minerals. During a Martian summer in the southern hemisphere, the planet experiences dust storms that can grow to encompass the entire planet. At other times of the year, dust devils and dusty skies are a persistent problem. This hazard has claimed robotic explorers that rely on solar panels to charge their batteries, like NASA’s Opportunityrover and the InSightlander, which ended their missions in 2018 and 2022, respectively.
Martian dust has also been a persistent challenge for the Ingenuity helicopter, the rotorcraft that has been exploring Mars alongside NASA’s Perseverance rover since February 2021. Luckily, the way it has kicked up dust has provided vital data that could prove invaluable for rotorcraft sent to explore other extraterrestrial environments in the future. Using this data, a team of researchers (with support from NASA) has completed the first real-world study of Martian dust dynamics, which will support missions to Mars and Titan (Saturn’s largest moon) in this and the next decade.
For space agencies and the commercial space industry, the priorities of the next two decades are clear. First, astronauts will be sent to the Moon for the first time since the Apollo Era, followed by the creation of permanent infrastructure that will allow them to say there for extended periods. Then, the first crewed missions will be sent to Mars, with follow-up missions every 26 months, culminating in the creation of surface habitats (and maybe a permanent base). To meet these objectives, space agencies are investigating next-generation propulsion, power, and life support systems.
This includes solar-electric propulsion (SEP), where solar energy is used to power extremely fuel-efficient Hall-Effect thrusters. Similarly, they are looking into nuclear thermal propulsion (NTP) and compact nuclear reactors, allowing for shorter transit times and providing a steady power supply for Lunar and Martian habitats. Beyond NASA, the UK Space Agency (UKSA) has partnered with Rolls-Royce to develop nuclear systems for space exploration. In a recent tweet, the international auto and aerospace giant provided a teaser of what their “micro-reactor” will look like.
The frontiers of astronomy are being pushed regularly these days thanks to next-generation telescopes and scientific collaborations. Even so, astronomers are still waiting to peel back the veil of the cosmic “Dark Ages,” which lasted from roughly 370,000 to 1 billion years after the Big Bang, where the Universe was shrouded with light-obscuring neutral hydrogen. The first stars and galaxies formed during this same period (ca. 100 to 500 million years), slowly dispelling the “darkness.” This period is known as the Epoch of Reionization, or as many astronomers call it: Cosmic Dawn.
By probing this period with advanced radio telescopes, astronomers will gain valuable insights into how the first galaxies formed and evolved. This is the purpose of the Hydrogen Epoch of Reionization Array (HERA), a radio telescope dedicated to observing the large-scale structure of the cosmos during and before the Epoch of Reionization located in the Karoo desert in South Africa. In a recent paper, the HERA Collaboration reports how it doubled the array’s sensitivity and how their observations will lead to the first 3D map of Cosmic Dawn.
It is an exciting time for astronomers and cosmologists. Since the James Webb Space Telescope (JWST), astronomers have been treated to the most vivid and detailed images of the Universe ever taken. Webb‘s powerful infrared imagers, spectrometers, and coronographs will allow for even more in the near future, including everything from surveys of the early Universe to direct imaging studies of exoplanets. Moreover, several next-generation telescopes will become operational in the coming years with 30-meter (~98.5 feet) primary mirrors, adaptive optics, spectrometers, and coronographs.
Even with these impressive instruments, astronomers and cosmologists look forward to an era when even more sophisticated and powerful telescopes are available. For example, Zachary Cordero of the Massachusetts Institute of Technology (MIT) recently proposed a telescope with a 100-meter (328-foot) primary mirror that would be autonomously constructed in space and bent into shape by electrostatic actuators. His proposal was one of several concepts selected this year by the NASA Innovative Advanced Concepts (NIAC) program for Phase I development.
Like Gravitational Waves (GWs) and Gamma-Ray Bursts (GRBs), Fast Radio Bursts (FRBs) are one of the most powerful and mysterious astronomical phenomena today. These transient events consist of bursts that put out more energy in a millisecond than the Sun does in three days. While most bursts last mere milliseconds, there have been rare cases where FRBs were found repeating. While astronomers are still unsure what causes them and opinions vary, dedicated observatories and international collaborations have dramatically increased the number of events available for study.
The coming decades of space exploration will see astronauts return to the Moon, the first crewed missions to Mars, and robotic missions to the outer Solar System (among other things). These missions will leverage innovative technologies that allow faster transits, long-duration stays, and sustainable living far from Earth. To this end, NASA and other space agencies are investigating nuclear applications, especially where energy and propulsion are concerned. Many of these proposals have been on the books since the early space age and have been thoroughly validated.
On Tuesday, January 24th, NASA and the Defense Advanced Research Projects Agency (DARPA) announced they were launching an interagency agreement to develop a nuclear-thermal propulsion (NTP) concept. The proposed nuclear rocket is known as the Demonstration Rocket for Agile Cislunar Operations (DRACO), which would enable fast-transit missions to Mars (weeks instead of months). This three-phase program will culminate with a demonstration of the DRACO in orbit, which is expected to occur by early 2027.
In 2033, NASA and China plan to send the first crewed missions to Mars. These missions will launch every two years when Earth and Mars are at the closest points in their orbits (Mars Opposition). It will take these missions six to nine months to reach the Red Planet using conventional technology. This means that astronauts could spend up to a year and a half in microgravity, followed by months of surface operations in Martian gravity (roughly 40% of Earth gravity). This could have drastic consequences for astronaut health, including muscle atrophy, bone density loss, and psychological effects.
Aboard the International Space Station (ISS), astronauts maintain a strict exercise regimen to mitigate these effects. However, astronauts will not have the same option while in transit to Mars since their vehicles (the Orion spacecraft) have significantly less volume. To address this challenge, Professor Marni Boppart and her colleagues at the Beckman Institute for Advanced Science and Technology are developing a process using regenerative cells. This work could help ensure that astronauts arrive at Mars healthy, hearty, and ready to explore!
In the 1970s, astronomers discovered that the persistent radio source at the center of our galaxy was a supermassive black hole (SMBH). Today, this gravitational behemoth is known as Sagittarius A* and has a mass roughly 4 million times that of the Sun. Since then, surveys have shown that SMBHs reside at the center of most massive galaxies and play a vital role in star formation and galactic evolution. In addition, the way these black holes consume gas and dust causes their respective galaxies to emit a tremendous amount of radiation from their Galactic Centers.
These are what astronomers refer to as Active Galactic Nuclei (AGN), or quasars, which can become so bright that they temporarily outshine all the stars in their disks. In fact, AGNs are the most powerful compact steady sources of energy in the Universe, which is why astronomers are always trying to get a closer look at them. For instance, a new study led by the University of California, Santa Cruz (UCSC) indicates that scientists have substantially underestimated the amount of energy emitted by AGN by not recognizing the extent to which their light is dimmed by dust.
Today, multiple space agencies are investigating cutting-edge propulsion ideas that will allow for rapid transits to other bodies in the Solar System. These include NASA’s Nuclear-Thermal or Nuclear-Electric Propulsion (NTP/NEP) concepts that could enable transit times to Mars in 100 days (or even 45) and a nuclear-powered Chinese spacecraft that could explore Neptune and its largest moon, Triton. While these and other ideas could allow for interplanetary exploration, getting beyond the Solar System presents some major challenges.
As we explored in a previous article, it would take spacecraft using conventional propulsion anywhere from 19,000 to 81,000 years to reach even the nearest star, Proxima Centauri (4.25 light-years from Earth). To this end, engineers have been researching proposals for uncrewed spacecraft that rely on beams of directed energy (lasers) to accelerate light sails to a fraction of the speed of light. A new idea proposed by researchers from UCLA envisions a twist on the beam-sail idea: a pellet-beam concept that could accelerate a 1-ton spacecraft to the edge of the Solar System in less than 20 years.
NASA and the China National Space Agency (CNSA) plan to mount the first crewed missions to Mars in the next decade. These will commence with a crew launching in 2033, with follow-up missions launching every 26 months to coincide with Mars and Earth being at the closest point in their orbits. These missions will culminate with the creation of outposts that future astronauts will use, possibly leading to permanent habitats. In recent decades, NASA has conducted design studies and competitions (like the 3D-Printed Habitat Challenge) to investigate possible designs and construction methods.
For instance, in the Mars Design Reference Architecture 5.0, NASA describes a “commuter” architecture based on a “centrally located, monolithic habitat” of lightweight inflatable habitats. However, a new proposal envisions the creation of a base using organisms that extract metals from sand and rock (a process known as biomineralization). Rather than hauling construction materials or prefabricated modules aboard a spaceship, astronauts bound for Mars could bring synthetic bacteria cultures that would allow them to grow their habitats from the Red Planet itself.