The mysteries of outer space have mesmerized Earth-bound humans for centuries. Even before Galileo first observed sunspots and supernovas, people were fascinated with the bright objects they saw in the night sky. In an attempt to satisfy that curiosity, scientists and engineers have continuously improved on the telescope, a technological marvel of the early 1600s.

Since then, a dozen astronauts walked on the moon. Seven spacecrafts landed on Mars. Pluto got demoted. And satellites captured images of astronomical objects more than 13 billion light years away.

But there’s still endless more to explore.

To prepare the next generation of space researchers, UT Arlington recently partnered with the NASA Johnson Space Center to provide unsurpassed training opportunities for its students. They will be guided by UTA professors who are tackling the wonders of the universe from a variety of angles, as they work to better understand and predict dangerous geomagnetic storms, investigate overlooked stars that may have the potential to host life, and discover whether extrasolar moons exist.

Even if the mysteries of the cosmos can never truly be solved, physicists at UT Arlington are providing a model of relentless investigation that should help inspire future space explorers to take up the quest.

Space Weather Forecast

Though she won’t show up on your local news, Yue Deng is a meteorologist of sorts.

The physics associate professor studies space weather events—activities caused by the sun that affect the near-Earth environment. Solar flares, coronal mass ejections, geomagnetic storms caused by solar wind, and other such phenomena have the potential to wreak havoc on our planet, damaging satellites, power grids, and GPS systems.

Much like weather predictions can cause us to change our travel plans, predictions of dangerous space weather events give scientists the chance to enact protective measures for the near-Earth environment. Dr. Deng’s current project, which is funded by a four-year NASA grant, focuses on how things like solar flares drive vertical winds to affect electrodynamics in the Earth’s upper atmosphere.

Yue Deng's research will make it easier to predict space weather events like solar flares.

“Almost all the influence of space weather on our society is affected by dynamics in the upper atmosphere,” she explains. “Neutral wind in the upper atmosphere is very difficult to model and measure, but it is still one of the most important parameters to consider.”

Gaining a better understanding of the dynamics of the sun-Earth relationship should allow Deng to more accurately predict the consequences here on land. This is important because during a geomagnetic storm, highly charged particles can damage satellite instruments or cause communications interruptions. Space weather also can inflict billions of dollars in electrical infrastructure damage and disrupt GPS navigation, resulting in location inaccuracies and potential hazards not only for travellers, but also for the military troops that rely on such technology for their missions.

Geomagnetic storms can even change the aurora regions, sometimes expanding them as far south as Texas. While beautiful to watch, auroras emit 10 times the normal amount of atmospheric X-rays. Thus when they expand, it forces air traffic controllers to change flight paths so passengers aren’t exposed to dangerous levels of radiation. Knowing about such storms in advance would allow the companies that operate satellites, aircraft, and power grids to prepare for communications inaccuracies and possible damage to equipment.

To help make the space weather predictions, Deng proposed a new way to study vertical wind using the Global Ionosphere-Thermosphere Model, or GITM, which offers a 3-D perspective of the effects of electrodynamic energy from the sun and solar wind. She is a core developer of the GITM, a model that helps her and her NASA-funded student assistants calculate the velocity, density, and temperature of both charged and neutral particles in the upper atmosphere during a storm.

“Our upper atmosphere is almost the last defense for protecting us from the direct influence of solar and geomagnetic storms,” Deng says. “We must know the status of the atmosphere and how it changes in our solar system.”

As should be obvious, when it comes to safeguarding our infrastructure, every minute counts. While current technology can only forecast such storms a couple of hours in advance, the hope is that researchers soon will be able to provide at least 24 hours’ notice.

Some Like It Hot

While Deng attempts to protect Earth’s inhabitants from the sun, physics Professor Manfred Cuntz is trying to determine whether bigger and hotter stars have hospitable regions that could potentially host extrasolar life.

Scientists know that G-type stars—such as our sun—have habitable zones, which are determined by temperature, UV radiation, luminosity, and other factors. Astrophysicists believe that K- and M-type stars, smaller and cooler than our sun, are also candidates for habitable regions because their relatively long life spans allow enough time for life-forms to originate and flourish.

But Dr. Cuntz thinks that an overlooked class of stars, F-type, may also be capable of providing the necessary environment to host life. Though the theory isn’t new, Cuntz says his research considers the effect of stellar evolution, which other studies haven’t addressed.

He and his former doctoral student Satoko Sato, along with a team of researchers from the University of Guanajuato in Mexico, have studied sets of F-type star systems to identify environmental conditions—stability, luminosity, temperature, radiation, and more—favorable for hosting life.

Stars don’t last forever. Eventually, their time winds down and they die, usually over the course of billions of years. A star’s main sequence, its slowest phase of evolution, offers the most stable climate conditions for close-by planets and is the most likely time life could develop. F-type stars have a much shorter main-sequence life span (about 2 billion years) compared to our sun (about 10 billion years) and K- and M-type stars (hundreds of billions of years). Despite this, Cuntz believes the period is long enough for life to thrive.

“Also in F-type stars’ favor is their greater luminosity, which offers a wider climatological habitable zone compared with G-, K-, or M-type stars,” he adds.

Working against F-type stars’ chance of hosting life, at least from a statistical point of view, is their relative rarity in the universe. Their greater mass and hotter temperatures also mean they emit more ultraviolet radiation, which is hazardous to carbon-based life-forms. However, for the latter, Cuntz and his colleagues have determined that relatively low estimates of UV radiation at the outer rim of an F-type star’s habitable zone may allow carbon-based life-forms to survive. A protective planetary atmosphere also could improve climate conditions.

“Our focus is to understand and quantify and make predictions,” he says. “We’re not yet in the position to find alien life. However, our research is one piece in the field of astrobiology aimed at searching for life outside our solar system.”

Hunting Elusive Exomoons

Scientists have discovered nearly 2,000 exoplanets—planets that orbit all sizes of stars outside our solar system—since the early 1990s. But no one has found an exomoon orbiting any of them.

The reason is fairly simple: Our current technology is too limited. While NASA’s powerful Kepler space telescope can spot Jupiter-sized exoplanets, it just isn’t sensitive enough to find significantly smaller exomoons, even those as large as Earth.

Professor Manfred Cuntz is searching stars for their life-hosting potential.

But physics Professor Zdzislaw Musielak has come up with an idea to potentially detect such small celestial objects. Instead of trying to observe an exomoon visibly, Dr. Musielak proposes using radio waves to sense the magnetic interaction between the exomoon and the exoplanet it orbits. For example, in our solar system, the radio waves used to detect Jupiter’s moon Io have a specific frequency based on planetary radio emissions. Musielak and two of his doctoral students, Joaquin Noyola and Suman Satyal, set out to determine whether the exomoons would produce similar emissions and, if so, how to extrapolate this method to other solar systems. (Noyola will complete the research for his doctoral dissertation.)

The trio’s research outlines the calculations used to predict the range of radio wave frequencies coming from objects in the universe. These results would then be used to determine which stars and exoplanets would be the best candidates to search for exomoons.

Making the theory even more exciting, Musielak says, is the possibility of discovering an exomoon in a habitable zone, which would increase the potential for finding extraterrestrial life. Scientists already have found Jupiter-sized exoplanets orbiting their stars in habitable zones, and while our own Jupiter could not host life (as it is made up of mostly gas), an exomoon orbiting a similar type of exoplanet does have that potential. The exomoon would have to be big enough to have an atmosphere (i.e., the size of Mars or larger) and warm enough that water remains in a liquid state. These qualities could make the exomoon resemble Earth.

Musielak says astronomers might already be using his method to search the universe for exomoons.

“Who will be the lucky one to point the telescope in the right direction and find the first exomoon?” he asks. “Once the first one is found, we will find more and more. The issue is detecting the first one.”

As Musielak, Cuntz, and Deng comb the skies seeking answers, they are teaching their students to do the same—to think futuristically and ask questions that have the potential to greatly influence and alter the way we understand space.

Top Photograph by Sky Noir Photography by Bill Dickinson