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When it comes to transforming obstacles into opportunities, it’s all about a “grow where you’re planted” mentality, says Shawnta Ball, a program support specialist in Goddard’s education office.

Name: Shawnta Ball

Title: Program Support Specialist

Formal Job Classification: Administrative Support Assistant

Organization: Office of STEM Engagement (OSTEM, Code 160)

“Rather than succumbing to challenges or setbacks, I viewed them as opportunities to learn and adapt,” says Shawnta Ball, program support specialist in the Office of STEM Engagement at NASA’s Goddard Space Flight Center in Greenbelt, Md.Red Cox Photography; courtesy Shawnta Ball

How would you describe your job at Goddard?

I contribute to the vitality of our office by providing crucial support to various programs. I joined Goddard in March 2020 and witnessed the organization undergo significant changes. Currently, we are in a phase of revitalization following the challenges posed by the pandemic. We now have a team working enthusiastically to revive some of the older programs.

Among our initiatives is the resurgence of K-12 programs, where we engage with schools in our region. My focus primarily involves collaborating with high schools and middle schools, reaching out to instill the NASA way of thinking and inspiring students to see the impact of a STEM education. We are dedicated to fostering a mindset that emphasizes working at NASA in science, technology, engineering, and math roles beyond being an astronaut.

Additionally, I serve as the liaison for diversity, equity, inclusion, and accessibility between NASA’s Office of Diversity and Equal Opportunity and OSTEM. Our goal is to ensure that our processes embrace everyone, irrespective of their background or identity. I act as the bridge, pulling together diverse perspectives and information to create a more inclusive work environment.

I’m also actively involved in two solicitations — one for Minority University Research and Education Project (MUREP) OCEAN related projects, and another focused on Data Science Equity, Access and Priority (DEAP). We collaborate with faculty to award research grants, reaching out to individuals who might not typically hear about these opportunities but possess the skills and potential to excel.

What path led you to this role?

My journey with NASA started in 2002, and I arrived at Goddard in 2020 after being part of the Office of STEM Engagement at headquarters in Washington. Embarking on my career in the government at the age of 16, I faced a unique and early entry into the professional world. Despite my youth, I embraced the opportunities presented to me and took on a series of diverse assignments within the government sector. This journey was marked by a steadfast commitment to the philosophy of “growing where I was planted.”

In practical terms, this philosophy implies a dedication to making the most of the current circumstances and roles, regardless of their initial nature or perceived limitations. Instead of constantly seeking new environments, I focused on developing my skills, gaining valuable experiences, and contributing meaningfully to each position I held. This approach allowed me to extract valuable lessons and skills from every assignment, fostering personal and professional growth in unexpected ways.

The belief in “growing where I was planted” also speaks to resilience and adaptability. Rather than succumbing to challenges or setbacks, I viewed them as opportunities to learn and adapt. This mindset not only helped me navigate the complexities of working in the government but also positioned me to thrive in a variety of roles over the years.

As a result of this philosophy, I built a foundation of skills, knowledge, and adaptability that eventually led me to my current role at Goddard. Each assignment, whether seemingly small or significant, played a crucial role in shaping my career trajectory and preparing me for the challenges and responsibilities I now undertake in supporting programs and initiatives at Goddard.

What’s the most exciting or interesting part of working at NASA?

Being in a position that involves interactions with celebrities has been one of the most enjoyable aspects of my work. It provides a unique glimpse into the individuals who contribute to TV programs, movies, and media that showcase NASA’s endeavors towards our society’s forward progression. During my early days, I had the fascinating role of booking meetings that involved notable figures, and although the interaction was swift, the experience of seeing them in person was truly thrilling.

While working in the administrator’s office at headquarters, I had the privilege of witnessing the arrival of news reporters, city mayors, congressmen and women, and astronauts who came to meet with the administrator. Sitting in anticipation, I played a behind-the-scenes role, having foreknowledge of their visits and assisting in the planning process. Although my involvement was indirect, the opportunity to be in proximity to these space explorers and others and to play a part in coordinating their interactions was both rewarding and awe-inspiring.

Shawnta Ball poses with a “Hidden Figures Way” street sign at NASA Headquarters in Washington.Shawnta Ball

I’ve had the privilege to meet and greet famous people and directly supported three astronaut-turned-supervisors. However, one standout memory involves meeting Nichelle Nichols, who played Uhura on “Star Trek,”  at the final space shuttle launch. STS-135, the last flight of the orbiter Atlantis, lifted off from Launch Pad 39A at NASA’s Kennedy Space Center in Florida on July 8, 2011. I will always be grateful to Ms. Nichols for the real-life role she played at NASA, which was to recruit minority and female astronauts and personnel for the agency’s Space Shuttle Program.

The sheer thought of being in the company of someone of her stature and witnessing firsthand the intersection of entertainment and NASA’s mission left a lasting impression. These encounters not only added a layer of excitement to my role but also reinforced the significance of the work we do at NASA, captivating the attention of influential figures who contribute to sharing our stories with the world.

By Marta Hill
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Conversations With Goddard is a collection of Q&A profiles highlighting the breadth and depth of NASA’s Goddard Space Flight Center’s talented and diverse workforce. The Conversations have been published twice a month on average since May 2011. Read past editions on Goddard’s “Our People” webpage.

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Details Last Updated Apr 11, 2024 EditorRob GarnerContactRob Garnerrob.garner@nasa.govLocationGoddard Space Flight Center Related Terms

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We explore seven of the best solar eclipses to look out for over the next 10 years.

Changes in the

New research suggests Exoplanet K2-18b may actually be a gas-rich planet with no habitable surface instead of a habitable water world.

The post The Planet K2-18b May Not Be Habitable After All appeared first on Sky & Telescope.

Image: Blowtorch effect of satellite reentry

A small early-stage trial of the approach, which involves testing dozens of drug combinations on thousands of dishes of cells, may help people with cancer live for longer

A small early-stage trial of the approach, which involves testing dozens of drug combinations on thousands of dishes of cells, may help people with cancer live for longer

The first non-American to walk on the moon will be a Japanese astronaut. Two JAXA astronauts will fly on future Artemis landing missions in return for Japan providing a pressurized moon rover.

Ground-level ozone, a product of pollution from cars, degrades insect pheromones, and this can result in mismatched mating and sterile offspring

Ground-level ozone, a product of pollution from cars, degrades insect pheromones, and this can result in mismatched mating and sterile offspring

We don’t know what alien life might look like, but if other civilisations can colonise multiple worlds, we might see planets that look unusually similar

We don’t know what alien life might look like, but if other civilisations can colonise multiple worlds, we might see planets that look unusually similar

The crime issue, a focus of the 2024 presidential election, is sometimes rooted in the misplaced fears of people who live in some of the safest places

How can future lunar exploration communicate from the far side of the Moon despite never being inline with the Earth? This is what a recent study submitted to IEEE Transactions on Aerospace and Electronic Systems hopes to address as a pair of researchers from the Polytechnique Montréal investigated the potential for a wireless power transmission method (WPT) comprised of anywhere from one to three satellites located at Earth-Moon Lagrange Point 2 (EMLP-2) and a solar-powered receiver on the far side of the Moon. This study holds the potential to help scientists and future lunar astronauts maintain constant communication between the Earth and Moon since the lunar far side of the Moon is always facing away from Earth from the Moon’s rotation being almost entirely synced with its orbit around the Earth.

Here, Universe Today discusses this research with Dr. Gunes Karabulut Kurt, who is an associate professor at IEEE Polytechnique Montréal and the study’s co-author, regarding the motivation behind the study, significant results, follow-up research, and implications for WPT. So, what was the motivation behind this study?

“This research is motivated by the objective of overcoming the logistical and technical challenges associated with using traditional cables on the Moon’s surface,” Dr. Kurt tells Universe Today. “Laying cables on the Moon’s rough, dusty surface would lead to ongoing maintenance and wear problems, as lunar dust is highly abrasive. On the other hand, transporting large quantities of cables to the Moon requires a significant amount of fuel, which adds considerably to the mission’s costs.”

For the study, the researchers used a myriad of calculations and computer models to ascertain if one, two, or three satellites are sufficient within an EMLP-2 halo orbit to maintain both constant coverage of the lunar far side (LFS) and line of sight with the Earth. For context, EMLP-2 is located on the far side of the Moon with the halo orbit being perpendicular—or sideways—to the Moon’s orbit. The calculations involved in the study included the distances between each satellite, the antenna angles between the satellites and surface receiver, the amount of LFS surface coverage, and the amount of transmitted power between the satellites and LFS surface antennae. So, what were the most significant results from this study?

Dr. Kurt tells Universe Today their models concluded that three satellites in an EMLP-2 halo orbit and operating at equal distances from each other could “achieve continuous power beaming to a receiver optical antenna anywhere on the lunar far side” while maintaining 100 percent LFS coverage and line of sight with the Earth. “Aside triple satellite scheme that provides continuous LFS full coverage, even a two-satellite configuration provides full coverage during 88.60% of a full cycle around the EMLP-2 halo orbit,” Dr. Kurt adds.

Schematic from Figure 1 of the study displaying the wireless power transmission and receiver on the lunar far side with three satellites (SPS-1, SPS-2, and SPS-3) in a halo orbit at the Earth-Moon Lagrange Point 2. (Credit: Donmez & Kurt (2024))

Regarding follow-up research, Dr. Kurt tells Universe Today, “Our future studies will focus on more complex harvesting and transmission models to get closer to reality. On the other hand, an approach that takes into account the irregular nature of lunar dust and the variation in its density due to environmental factors such as subsolar angle and others. In the future, if research in this field continues, explore this experimentally with lunar dust simulants and lasers.”

This study comes as NASA is preparing to send astronauts to the Moon for the first time since 1972 with the Artemis program, whose goal will be to land the first woman and person of color on the lunar surface. With the success of the Artemis 1 mission in November 2022 that consisted of an uncrewed Orion capsule orbiting the Moon, NASA is currently targeting September 2025 for their Artemis 2 mission, which is scheduled to be a 10-day, 4-person crewed mission using the Orion capsule for a lunar flyby, whose goal will be to conduct a full systems checkout of the Orion capsule. Therefore, what implications can this study have for the upcoming Artemis missions, or any future human exploration of the Moon?

“The findings have implications for the design of energy transmission systems on the Moon,” Dr. Kurt tells Universe Today. “A better understanding of the wireless transmission disruptors such as lunar dust can lead to the development of more efficient and reliable systems for powering lunar missions and infrastructure, including those related to the Artemis program and future human exploration efforts.”

If successful, Artemis 2 will be followed by Artemis 3 in September 2026, which will also consist of a 4-person crew with two crew members landing on the lunar surface and an approximate mission duration of 30 days. This will be followed by Artemis 4, Artemis 5, and Artemis 6, which are currently scheduled for September 2028, September 2029, and September 2030, respectively, with each mission increasing in both the number of astronauts landing on the lunar surface along with anticipated deliveries of lunar habitat modules and lunar rovers, as well.

“Moreover, the Artemis mission is targeting the lunar south pole for its landing sites,” Dr. Kurt tells Universe Today. “This region is of particular interest due to the presence of peaks of eternal light (PELs), which receive almost continuous sunlight and permanently shadowed regions (PSRs), which are potential sites for resources such as water ice. These contrasting conditions are ideal for the application of wireless energy transmission (laser power beaming technology), which could provide a continuous power supply in shadowed areas by transmitting energy wirelessly from illuminated regions.”

The reason these PSRs exist is due to the Moon’s low obliquity, or axial tilt, which the study notes is 6.68 degrees. For context, the Earth’s obliquity is 23.44 degrees. This means there are areas, and specifically craters, at both the north and south poles on the Moon that do not receive any sunlight, hence the name “permanently shadowed regions”. As noted by Dr. Kurt, these PSRs could be home to deposits of water ice within these deep, dark craters that astronauts could use for water, fuel, and other needs.

The Artemis missions plan to deliver not only astronauts to the lunar surface, but a habitat and lunar rovers with the goal of establishing a permanent human presence on the Moon. This will provide opportunities for demonstrating new space technologies that can be used for both lunar exploration and future human missions to Mars, which are a part of NASA’s Moon to Mars Architecture.

“Current missions plan to re-use Earth-proven technology,” Dr. Kurt tells Universe Today. “This mindset may undermine the blue-sky design approach, where researchers are encouraged to think freely, explore creative ideas, and push the boundaries of what’s possible without being confined by constraints such as specific project requirements or backward compatibility. In our work we aim to include multi-functionality aspects, which are not a necessity for terrestrial applications but may turn out to be essential for future space missions.”

How will this wireless power transmission method help improve communication from the far side of the Moon to Earth in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Wireless Power Transmission Could Enable Exploration of the Far Side of the Moon appeared first on Universe Today.

Millions of people took a trip over to the US or Mexico to try and catch a glimpse of the 2024 total solar eclipse. Whether you took the trip or not, if you have since been bitten by the eclipse bug then there are three upcoming eclipses over the next couple of years. August 2026 sees an eclipse passing from Greenland, Iceland and Spain, 2027 sees an eclipse over North Africa and in 2028 Australia all be the place to be. With loads of possibilities for all locations, it’s time to get planning. 

Many people across the World make attempts to witness solar eclipses, often travelling hundreds if not thousands of kilometres. I tried such a journey back in 1999 travelling from my home in Norfolk, UK to Cornwall, a journey of over 600 kilometres. Alas, and like many eclipse chasers before me, cloud thwarted my view. However, the experience of the daylight turning to dusk in a few seconds at the onset of totality, the birds singing as the ‘Sun came out again’, it was all such an incredible amazing experience. 

Since that cloudy experience in Cornwall I committed to one day, actually seeing a total solar eclipse. I have seen partials, and they are wonderful but nothing like the majesty of a total solar eclipse.

What are we talking about? Well, the Moon travels around the Earth and the Earth travels around the Sun. It’s these changing relative positions that lead to the lunar phases. When the Moon is broadly between the Sun and Earth we experience a new moon phase. You might therefore wonder why we don’t experience a total solar eclipse every new moon! The answer lies in the obits; the orbit of the Moon around Earth is tilted by about 5 degrees in reference to the Earth’s orbit around the Sun. During most new moons the Moon is slightly above or below the Sun when viewed from Earth. It’s only when the two orbits intersect at a new moon that we see a total solar eclipse. 

This is exactly what happened on 8 April 2024, a total solar eclipse became visible as the Moon silently passed directly between the Earth and Sun. When we get a perfect alignment of three celestial bodies like this its called a Syzygy, a wonderful word and great for a game of Scrabble. Totality for this eclipse lasted for about 4 minutes depending on the location of the observer. That’s the chief difference between a solar eclipse and a lunar eclipse. Lunar eclipses are visible anywhere on Earth that the Moon is visible but solar eclipses are only visible from very specific locations on Earth. 

Over the next few years there are some great opportunities to see total solar eclipses. Unless you are lucky, you will have to travel but the next opportunity takes place on 12 August 2026. You will need to be travelling to either Greenland, Iceland or Spain to catch this eclipse. Greenland and Iceland are the best option as Spain will only get the eclipse toward the end of the day. Next up is 2027 when an eclipse takes place on the 2 August visible from North Africa. After that, it’s 2028 but for southern hemisphere observers so its a trip to Australia. 

Wherever you venture to observe a total solar eclipse, it is imperative that you be careful when observing it. The ONLY time it is safe to observe a solar eclipse directly is during the moments of totality. As soon as the bright parts of the solar photosphere are visible, then direct observing is dangerous and will lead to damage to your eyes. If you are planning a trip to observe a total solar eclipse, be sure you are prepared and know exactly when and how you can observe it to ensure your eyesight remains safe. 

Source : Time and Date Eclipse Calendar

The post Here are the Next Three Total Solar Eclipses Coming Up appeared first on Universe Today.

It’s a measure of human ingenuity and curiosity that scientists debate the possibility of life on Venus. They established long ago that Venus’ surface is absolutely hostile to life. But didn’t scientists find a biomarker in the planet’s clouds? Could life exist there, never touching the planet’s sweltering surface?

It seems to depend on who you ask.

We’ll start with phosphine.

Phosphine is a biomarker, and in 2020, researchers reported the detection of phosphine in Venus’ atmosphere. There should be no phosphine because phosphorous should be oxidized in the planet’s atmosphere. According to the paper, no abiotic source could explain the quantity found, about 20 ppb.

Subsequently, the detection was challenged. When others tried to find it, they couldn’t. Also, the original paper’s authors informed everyone of an error in their data processing that could’ve affected the conclusions. Those authors examined the issue again and mostly stood by their original detection.

At this point, the phosphine issue seems unsettled. But if it is present in Venus’ atmosphere and is biological in nature, where could it be coming from? Venus’s surface is out of the question.

That leaves Venus’ cloud-filled atmosphere as the only abode of life. While the idea might seem ridiculous at first glance, researchers have dug into the idea and generated some interesting results.

In a new paper, researchers examine the idea of microscopic life that lives and reproduces in water droplets in Venus’s clouds. The title is “Necessary Conditions for Earthly Life Floating in the Venusian Atmosphere.” The lead author is Jennifer Abreu from the Department of Physics and Astronomy, Lehman College, City University of New York. The paper is currently in pre-print.

Spacecraft have struggled to contend with the harsh conditions on Venus’s surface. The Soviet Venera 13 lander captured this image of the planet’s surface in March of 1982. NASA/courtesy of nasaimages.org

“It has long been known that the surface of Venus is too harsh an environment for life,” the authors write. “Contrariwise, it has long been speculated that the clouds of Venus offer a favourable habitat for life but regulated to be domiciled at an essentially fixed altitude.” So, if life existed in the clouds, it wouldn’t be spread throughout. Only certain altitudes appear to have what’s needed for life to survive.

The type of life the authors envision aligns with other thinking about Venusian atmospheric life. “The archetype living thing <being> the spherical hydrogen gasbag isopycnic organism,” they state. (Isopycnic means constant density; the other terms are self-explanatory.)

Here’s how the authors think it could work.

Venus is shrouded in clouds so thick we can only see the surface with radar. The clouds reach all the way around the globe. The cloud base is about 47 km (29 miles) from the surface, where the temperature is about 100 C (212 F.) At equatorial and mid-latitudes, they extend up to a 74 km (46 miles) altitude, and at the poles, they extend up to about 65 km (40 miles.)

Cloud structure in the Venusian atmosphere in 2016, revealed by observations in two ultraviolet bands by the Japanese spacecraft Akatsuki. Image Credit: Kevin M. Gill

The clouds can be subdivided into three layers based on the size of aerosol particles: the upper layer from
56.5 to 70 km altitude, the middle layer from 50.5 to 56.5 km, and the lower layer from 47.5 to 50.5 km. The smallest droplets can float in all three layers. But the largest droplets, which the authors call type 3 droplets with a radius of 4 µm, are only present in the middle and lower layers.

“It has long been suspected that the cloud decks of Venus offer an aqueous habitat where microorganisms can grow and flourish,” the authors write. Everything life needs is there: “Carbon dioxide, sulfuric acid compounds, and ultraviolet (UV) light could give microbes food and energy.”

Because of temperature, life in Venus’ clouds would be restricted to a specific altitude range. At 50 km, the temperature is between 60 and 90 degrees Celsius (140 and 194 degrees Fahrenheit). The pressure at that altitude is about 1 Earth atmosphere.

This figure from the research shows the temperature and pressure throughout Venus’s atmosphere. Image Credit: Image Credit: S. Seager et al. 2021. doi:10.1089/ast.2020.2244

There’s a precedent for life existing in the clouds. It happens here on Earth, where scientists have observed bacteria, pollen, and even algae at altitudes as high as 15 km (9.3 miles.) There’s even evidence of bacteria growing in droplets in a super-cooled cloud high in the Alps. The understanding is that these organisms were carried aloft by wind, evaporation, eruptions, or even meteor impacts. But there’s an important difference between Earth’s and Venus’ clouds.

Earth’s clouds are transient. They form and dissolve constantly. But Venus’ clouds are long-lasting. They’re a stable environment compared to Earth’s clouds. In Earth’s clouds, aerosol particles are sustained for only a few days, while in Venus’ clouds, the particles can be sustained for much longer periods of time.

Add it all up, and you get stable cloud environments where aerosol particles can sustain themselves in an environment where energy and nutrients are available. The researchers say that though eventually aerosol particles and the life within them will fall to the surface, they have time to reproduce before that happens.

This image shows the cycle of Venusian aerial microbial life. Image Credit: S. Seager et al. 2021. doi:10.1089/ast.2020.2244

The idea of a microbial life cycle in Venusian clouds was developed by other researchers in their 2021 paper “The Venusian Lower Atmosphere Haze as a Depot for Desiccated Microbial Life: A Proposed Life Cycle for Persistence of the Venusian Aerial Biosphere.”

There are five steps in Venus’s proposed cloud lifecycle:

1. Dormant desiccated spores (black blobs) partially populate the lower haze layer of the atmosphere.
2. Updrafts transport them up to the habitable layer. The spores could travel up to the clouds via gravity waves.
3. Shortly after reaching the (middle and lower cloud) habitable layer, the spores act as cloud condensation nuclei, and more and more water gathers into a single droplet. Once the spores are surrounded by liquid with the necessary chemicals, they germinate and become metabolically active.
4. Metabolically active microbes (dashed blobs) grow and divide within liquid droplets (shown as solid circles in the figure). The liquid droplets continue to grow by coagulation.
5. Eventually, the droplets are large enough to settle out of the atmosphere gravitationally; higher temperatures and droplet evaporation trigger cell division and sporulation. The spores are smaller than the microbes and resist further downward sedimentation. They remain suspended in the lower haze layer (a depot of hibernating microbial life) to restart the cycle.

In this new work, the researchers focus on time.

“One of the key assumptions of the aerial life cycle put forward in Seager et al. 2021 is the timescale on which droplets would persist in the habitable layer to empower replication,” the authors write. “It is this that we now turn to study.”

This table from the research shows generation times for some common Earth bacteria. Image Credit: Abreu et al. 2024.

The authors used E. Coli generation times under optimal conditions in their work. In aerobic and nutrient-rich conditions, E. Coli can reproduce in 20 minutes. So, the E. Coli population will double three times in one hour. Bacteria must reproduce faster than they fall to the surface to sustain itself. They need to form a colony.

The researchers calculated that to sustain itself, the time it takes for bacteria to fall from the habitable part of the atmosphere to the inhabitable has to be longer than half an Earth day. As droplet size increases, the droplets would begin to sink. “As the droplet size approaches 100 µm, the droplets would start sinking to the lower haze layers,” they explain. However, their detailed calculations show that reproduction outpaces the fallout rate.

According to the team’s work, a population of bacteria could sustain itself in Venus’ clouds.

There are, obviously, still some questions. How certain are we that nutrients are available? Is there enough energy? Are there updrafts that can loft spores into the right layer of the atmosphere?

But the real big question is how was this all set in motion?

“An optimist might even imagine that the microbial life actually arose in a good-natured surface habitat, perhaps in a primitive ocean, before the planet suffered a runaway greenhouse, and the microbes lofted into the clouds,” the authors write. If that’s the case, this unique situation arose billions of years ago. Is there any other possibility? Could life have originated in the clouds?

Much scientific investigation into Venus, phosphine, clouds, and life relies on scant evidence. Few are willing to go out on a limb and proclaim that Venus can and does support life. We need more evidence.

For that, we have to wait for missions like the Venus Life Finder Mission. It’s a private mission being developed by Rocket Lab and a team from MIT. Who knows what VLF and other missions like DAVINCI and VERITAS will find? Stronger evidence of phosphine? Better data on Venus’ atmospheric layers and the conditions in them?

Life itself?

Artist’s impression of the Rocket Lab Mission to Venus. Credit: Rocket Lab

The post Could Life Exist in Water Droplet Worlds in Venus’ Atmosphere? appeared first on Universe Today.

On April 8, 2024, Peter Higgs passed away. Pioneering the discovery of the Higgs boson, the mark the theoretical physicist has left on physics is immense.

Jupiter and a slim crescent moon are the stand-out night sky sight in the evening sky right now.

Pink Floyd was wrong, there is no dark side to the Moon. There is however, a far side. The tidal effects between the Earth and Moon have caused this captured or synchronous rotation. The two sides display very different geographical features; the near side with mare and ancient volcanic flows while the far side displaying craters within craters. New research suggests the Moon has turned itself inside out with heavy elements like titanium returning to the surface. It’s now thought that a giant impact on the far side pushed titanium to the surface, creating a thinner more active near side. 

There have been a number of theories for the formation of the Moon; the capture theory and the accretion theory to name two of them. Perhaps the most accepted theory now is the giant impact theory which suggests Earth was struck by a large object, causing a lot of debris to be ejected into orbit. This material eventually coalesced to form the Moon we know and love today. 

In the decades that followed the Apollo missions, scientists studied the rocks returned by the astronauts. The studies revealed that many of the surface rocks contained unexpectedly high concentrations of titanium. More surprisingly was that satellite observations revealed these titanium rich minerals were far more common on the nearside and absent on the far-side. What is known is that the Moon formed fast and hot and would have been covered for a short period in an ocean of molten magma. The magma cooled and solidified forming the Moon’s crust but trapped below was the more dense material including titanium and iron. 

Sample collection on the surface of the Moon. Apollo 16 astronaut Charles M. Duke Jr. is shown collecting samples with the Lunar Roving Vehicle in the left background. Image: NASA

The dense material should have sunk to greater depths inside the Moon however over the years that followed something strange seems to have happened. The denser material did indeed sink, mixed with mantle but melted and returned to the surface as titanium rich lava flows. Debates have been raging whether this is exactly what happened but a new piece of research by a team at the University of Arizona Lunar and Planetary Laboratory offer more details about the process and how the interior of the Moon evolved.

It has already been suggested that the Moon may have suffered a giant impact on the far side causing the heavier elements to be forced over to the near side but the new study highlighted supporting evidence from gravitational anomalies. The team measured tiny variations in the Moon’s gravitational field from data from the GRAIL mission. GRAIL – or Gravity Recovery and Interior Laboratory – orbited the Moon to create the most accurate gravitational map of the Moon to date. Using GRAIL data the team discovered that titanium-iron oxide minerals had migrated to the near side and sunk to the interior in sheetlike cascades. This was consistent with models suggesting the event occurred more than 4.22 billion years ago. 

Global map of the Moon, as seen from the Clementine mission, showing the differences between the lunar near- and farside. Credit: NASA.

As paper co-author and LPL associate professor Jeff Andrews-Hanna said “The moon is fundamentally lopsided in every respect.” The near side feature known as Oceanus Procellarum is a great example. It is lower in elevation and has a lava flow covered thinner crust with high concentrations of titanium rich elements. This is very different on the far side. The strange and unique structure of the region is thought to be key in understanding the event that happened billions of years ago to shape the Moon we see today.

Source : How the Moon turned itself inside out

The post Finally, an Explanation for the Moon’s Radically Different Hemispheres appeared first on Universe Today.