Day: April 25, 2023

Mars is Earth’s next-door neighbor in the solar system — two rocky worlds with differences down to their very core, literally.

A new study based on seismic data obtained by NASA’s robotic InSight lander is offering a fuller understanding of the Martian deep interior and fresh details about dissimilarities between Earth, the third planet from the sun, and Mars, the fourth.

The research, informed by the first detection of seismic waves traveling through the core of a planet other than Earth, showed that the innermost layer of Mars is slightly smaller and denser than previously known. It also provided the best assessment to date of the composition of the Martian core.

Both planets possess cores comprised primarily of liquid iron. But about 20% of the Martian core is made up of elements lighter than iron — mostly sulfur, but also oxygen, carbon and a dash of hydrogen, the study found. That is about double the percentage of such elements in Earth’s core, meaning the Martian core is considerably less dense than our planet’s core — though more dense than a 2021 estimate based on a different type of data from the now-retired InSight.

“The deepest regions of Earth and Mars have different compositions —  likely a product both of the conditions and processes at work when the planets formed and of the material they are made from,” said seismologist Jessica Irving of the University of Bristol in England, lead author of the study published this week in the journal Proceedings of the National Academy of Sciences.

The study also refined the size of the Martian core, finding it has a diameter of about 2,212-2,249 miles (3,560-3,620 km), approximately 12-31 miles (20-50 km) smaller than previously estimated. The Martian core makes up a slightly smaller percentage of the planet’s diameter than does Earth’s core.

The nature of the core can play a role in governing whether a rocky planet or moon could harbor life. The core, for instance, is instrumental in generating Earth’s magnetic field that shields the planet from harmful solar and cosmic particle radiation.

“On planets and moons like Earth, there are silicate — rocky — outer layers and an iron-dominated metallic core. One of the most important ways a core can impact habitability is to generate a planetary dynamo,” Irving said.

“Earth’s core does this but Mars’ core does not — though it used to, billions of years ago. Mars’ core likely no longer has the energetic, turbulent motion which is needed to generate such a field,” Irving added.

Mars has a diameter of about 4,212 miles (6,779 km), compared to Earth’s diameter of about 7,918 miles (12,742 km), and Earth is almost seven times larger in total volume.

The behavior of seismic waves traveling through a planet can reveal details about its interior structure. The new findings stem from two seismic events that occurred on the opposite side of Mars from where the InSight lander — and specifically its seismometer device — sat on the planet’s surface.

The first was an August 2021 marsquake centered close to Valles Marineris, the solar system’s largest canyon. The second was a September 2021 meteorite impact that left a crater of about 425 feet (130 meters).

The U.S. space agency formally retired InSight in December after four years of operations, with an accumulation of dust preventing its solar-powered batteries from recharging.

“The InSight mission has been fantastically successful in helping us decipher the structure and conditions of the planet’s interior,” University of Maryland geophysicist and study co-author Vedran Lekic said. “Deploying a network of seismometers on Mars would lead to even more discoveries and help us understand the planet as a system, which we cannot do by just looking at its surface from orbit.”
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A Japanese company tried to land its own spacecraft on the moon early Wednesday, but its fate was unknown as flight controllers lost contact with it moments before the planned touchdown. 

Flight controllers peered at their screens in Tokyo, expressionless, as the minutes went by with still no word from the lander. 

A webcast commentator urged everyone to be patient, as the controllers investigated what might have happened. 

“Everyone, please give us a few minutes to confirm,” he urged. 

If successful, the company ispace would be the first private business to pull off a lunar landing. 

Only three governments have successfully landed on the moon: Russia, the United States and China. The spacecraft carried a mini lunar rover for the United Arab Emirates and a toylike robot from Japan designed to roll around in the moon dust. There were also items from private customers on board. 
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A Japanese space start-up will attempt Tuesday to become the first private company to put a lander on the Moon.   

If all goes to plan, ispace’s Hakuto-R Mission 1 lander will start its descent towards the lunar surface at around 15:40 GMT.   

It will slow its orbit some 100 kilometers above the Moon, then adjust its speed and altitude to make a “soft landing” around an hour later.   

Success is far from guaranteed. In April 2019, Israeli organization SpaceIL watched their lander crash into the Moon’s surface.   

ispace has announced three alternative landing sites and could shift the lunar descent date to April 26, May 1 or May 3, depending on conditions.   

“What we have accomplished so far is already a great achievement, and we are already applying lessons learned from this flight to our future missions,” ispace founder and CEO Takeshi Hakamada said earlier this month.   

“The stage is set. I am looking forward to witnessing this historic day, marking the beginning of a new era of commercial lunar missions.”   

The lander, standing just over two meters tall and weighing 340 kilograms, has been in lunar orbit since last month.   

It was launched from Earth in December on one of SpaceX’s Falcon 9 rockets after several delays.   

So far only the United States, Russia and China have managed to put a robot on the lunar surface, all through government-sponsored programs.   

However, Japan and the United States announced last year that they would cooperate on a plan to put a Japanese astronaut on the Moon by the end of the decade.   

SEE ALSO: A related video by VOA’s Alexander Kruglyakov

The lander is carrying several lunar rovers, including a miniature Japanese model of just eight centimeters that was jointly developed by Japan’s space agency with toy manufacturer Takara Tomy.   

The mission is also being closely watched by the United Arab Emirates, whose Rashid rover is aboard the lander as part of the nation’s expanding space program.   

The Gulf country is a newcomer to the space race but sent a probe into Mars’ orbit in 2021. If its rover successfully lands, it will be the Arab world’s first Moon mission.   

Hakuto means “white rabbit” in Japanese and references Japanese folklore that a white rabbit lives on the Moon.   

The project was one of five finalists in Google’s Lunar X Prize competition to land a rover on the Moon before a 2018 deadline, which passed without a winner.   

With just 200 employees, ispace has said it “aims to extend the sphere of human life into space and create a sustainable world by providing high-frequency, low-cost transportation services to the Moon.”   

Hakamada has touted the mission as laying “the groundwork for unleashing the Moon’s potential and transforming it into a robust and vibrant economic system.”   

The firm believes the Moon will support a population of 1,000 people by 2040, with 10,000 more visiting each year.   

It plans a second mission, tentatively scheduled for next year, involving both a lunar landing and the deployment of its own rover. 
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The U.S. Space Force said on Monday that Elon Musk’s SpaceX was granted approval to lease a second rocket launch complex at a military base in California, setting the space company up for its fifth launch site in the United States. 

Under the lease, SpaceX will launch its workhorse Falcon rockets from Space Launch Complex-6 at Vandenberg Space Force Base, a military launch site north of Los Angeles where the space company operates another launchpad. It has two others in Florida and its private Starbase site in south Texas. 

A Monday night Space Force statement said a letter of support for the decision was signed on Friday by Space Launch Delta 30 commander Col. Rob Long. The statement did not mention a duration for SpaceX’s lease. 

The new launch site, vacated last year by the Boeing-Lockheed joint venture United Launch Alliance, gives SpaceX more room to handle an increasingly busy launch schedule for commercial, government and internal satellite launches. 

Vandenberg Space Force Base allows for launches in a southern trajectory over the Pacific Ocean, which is often used for weather-monitoring, military or spy satellites that commonly rely on polar Earth orbits. 

SpaceX’s grant of Space Launch Complex-6 comes as rocket companies prepare to compete for the Pentagon’s Phase 3 National Security Space Launch program, a watershed military launch procurement effort expected to begin in the next year or so. 
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A spacecraft around Mars has sent back the most detailed photos yet of the red planet’s little moon. 

The United Arab Emirates’ Amal spacecraft flew within 100 kilometers (62 miles) of Deimos last month, and the close-up shots were released Monday. Amal — Arabic for Hope — got a two-for-one when Mars photobombed some of the images. It was the closest a spacecraft has been to Deimos in almost a half-century. 

The spacecraft also observed the little explored far side of the odd-shaped, cratered moon, just 15 kilometers by 12 kilometers by 12 kilometers (9 miles by 7 miles by 7 miles.) 

SEE ALSO: A related video by VOA’s Arash Arabasadi

Mars’ other moon, Phobos, is almost double that size and better understood since it orbits much closer to Mars — just 6,000 kilometers (3,700 miles) away, the closest of any planet’s moon in our solar system. 

Deimos’ orbit around Mars stretches 23,000 kilometers (14,000 miles) out. That’s close to the inner part of the spacecraft’s orbit — “which is what made observing Deimos such a compelling idea,” said the mission’s lead scientist Hessa al-Matroushi. 

“Phobos has got most of the attention up until now — now it’s Deimos’ turn!” she added in an email. 

Al-Matroushi and other scientists with the UAE Space Agency said these new images indicate Deimos is not an asteroid that got captured in Mars’ orbit eons ago, the leading theory until now. Instead, they say the moon appears to be of Martian origin — perhaps from the bigger Martian moon or from Mars itself. 

The findings were presented Monday at the European Geosciences Union’s general assembly in Vienna. 

Amal will continue to sweep past Deimos this year, but not as closely as the March 10 encounter, according to al-Matroushi. 

NASA’s Viking 2 came within 30 kilometers (19 miles) of Deimos in 1977. Since then, other spacecraft have photographed Deimos but from much farther away. 

Amal rocketed to Mars on July 19, 2020, one day shy of the 50th anniversary of humanity’s first moon landing — Earth’s moon, that is — by Apollo 11’s Neil Armstrong and Buzz Aldrin. 
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An intense solar storm has the northern lights gracing the skies farther south than usual. 

A blast of superhot material from the sun late last week hurled scorching gases known as plasma toward Earth at about 3 million kph, the National Oceanic and Atmospheric Administration said Monday. 

Earth felt the brunt of the storm Sunday, according to NOAA, with forecasters warning operators of power plants and spacecraft of the potential for disruption. 

“I don’t want any expectations of these green curtains moving back and forth” so far south, said Bill Murtagh, program coordinator at the NOAA Space Weather Prediction Center in Boulder, Colorado.  

Auroras were reported across parts of Europe and Asia. In the U.S., skygazers took in the sights from northern states such as Wisconsin and Washington, but also states farther south, including Colorado, California, New Mexico and even Arizona — mostly a reddish glow instead of the typical green shimmer. 

Although conditions have eased, auroras might still be visible as far south as South Dakota and Iowa late Monday and early Tuesday if skies are dark. 

The farther north, the better the chance of a show as the energized particles interact with the atmosphere closer to Earth, according to Murtagh. The farther south, the curvature of the Earth cuts off the possibility for the most dazzling scenes as the particles interact higher in the atmosphere. 

Murtagh said light pollution in Boulder prevented him from seeing the auroras Sunday night. But there could be more opportunities as the solar cycle ramps up. 

“Stay tuned, more to come,” he said. 

This was the third severe geomagnetic storm since the current 11-year solar cycle began in 2019, according to NOAA. The agency expects the cycle to peak in 2024. 

For those Down Under, the southern lights should provide equally good shows, Murtagh said. 
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