Artist’s impression of the Mars Base Camp in orbit around Mars. When missions to Mars begin, one of the greatest risks will be that posed by space radiation. Credit: Lockheed Martin
In 1972, the space race officially ended as NASA sent one last crew of astronauts to the surface of the moon (Apollo 17). This was the brass ring that both the US and the Soviets were reaching for, the “moonshot” that would determine who had supremacy in space. In the current age of renewed space exploration, the next great leap will clearly involve sending astronauts to Mars.
This will present many challenges that will need to be addressed in advance, many of which have to do with simply getting the astronauts there in one piece! These challenges were the subject of a presentation made by two Indian researchers at the SciTech Forum 2020, an annual event hosted by the International Academy of Astronautics (IAA), RUDN University, and the American Astronomical Society (AAS).
The study that describes their research findings recently appeared online and has been accepted for publication by Advances in Aeronautical Sciences (publication date pending). Both it and the presentation made at the SciTech Forum 2020 were conducted by Malaya Kumar Biswal and Ramesh Naidu Annavarapua—a graduate researcher and Associate Professor of Physics from Pondicherry University, India (respectively).
Their research was also the subject of a presentation made during the seventh session of the Space Biology Virtual Workshop hosted by the Lunar Planetary Institute (LPI) – which took place between Jan. 20th and 21st. As Biswal and Annavarapua indicated in their study and presentations, Mars occupies a special place in the hearts and minds of scientists and astrobiological researchers.
Next to Earth, Mars is the most habitable location in the solar system (by terrestrial standards). Multiple lines of evidence accumulated over the course of decades have also shown that it may have supported life at one time. Unfortunately, sending astronauts to Mars will inevitably entail a number of distinct challenges, which arise from logistics and technology to human factors and the distances involved.
Addressing these issues in advance is paramount if NASA and other space agencies hope to conduct the first crewed missions to Mars in the next decade and after. Based on their analysis, Biswal and Annavarapu identified 14 distinct challenges, which include (but are not limited to):
The flight trajectory for Mars and corrective maneuvers
Spacecraft and fuel management
Radiation, microgravity, and astronaut health
Isolation and psychological issues
Communications (in transit and on Mars)
The Mars approach and orbital insertion
All of these challenges experience some degree of overlap with one or more of the others listed. For instance, an obvious issue when it comes to planning missions to Mars is the sheer distance involved. Because of this, launch windows between Earth and Mars only occur every two years when our planets are at the closest in their orbits to each other (i.e., when Mars is in “opposition” relative to the sun).
During these windows, a spacecraft can make the journey from Earth to Mars in 150 to 300 days (about five to ten months). This makes resupply missions impractical since astronauts cannot wait that long to receive much-needed shipments of fuel, food, and other supplied. As Biswal told Universe Today via email, the distances involved also creates problems where astronaut safety and are power-generation are concerned:
“In case of any emergency situation, we cannot bring back astronauts from Mars [as we could] in the case of LEO or Lunar Missions… Similarly, distance reduces the solar flux from Earth orbit to Mars orbit resulting in the deficit power production which is very significant to power vehicle and maintain thermal stability (As again the far distance may lead to low environment temperature causing hypothermia and frost formation (especially in mouth).”
In other words, simply getting to Mars presents multiple specific challenges that Biswal and Annavarapu included in their analysis. When talking about astronaut healthy and safety, there are several specific challenges that come into play here as well. For instance, the fact that astronauts will be spending an several months in deep-space creates all kinds of risks for their physical and mental health.
For starters, there’s the psychological toll of being confined to a spacecraft cabin with other astronauts. There’s also the physical toll of long-term exposure to a microgravity environment. As research aboard the International Space Station (ISS) has shown—particularly, NASA’s Twin Study—spending up to a year in space takes a considerable toll on the human body.
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Credit: Universe Today
Beyond muscle and bone density loss, astronauts who’s spent long periods aboard the ISS also experienced a loss in eyesight, genetic changes, and long-term issues with their cardiovascular and circulation systems. There have also been instances of psychological effects, where astronauts experienced high levels of anxiety, insomnia, and depression.
But as Biswal indicated, the single-greatest and most obvious challenge is all the radiation (solar and cosmic) that the astronauts will be exposed to over the course of the entire mission:
“[The] greatest dangers include the risk of prolonged cancer and its effects due to exposure to both interplanetary radiation (during Mars transit) and surface radiation (during extended surface stay). Then, the effect of radiation cause improper brain coordination function and other brain-related diseases; then the psychological effect of the crew during complete isolation. Since the crewed mission relies on the performance of astronaut, the astronaut experience more health-related issues.”
In developed nations, people on Earth are exposed to an average of about 620 millirem (62 mSv) annually, or 1.7 millirems (0.17 mSv) a day. Meanwhile, NASA has conducted studies that have shown how a mission to Mars would result in a total exposure of about 1,000 mSv over a two and a half year period. This would consist of 600 mSv during a year-long round-trip, plus 400 mSv during an 18-month stay (while the planets realigned).
What that means is that astronauts will be exposed to 1.64 mSv a day while in transit and 0.73 mSv for every day that they are staying on Mars—that’s over 9.5 and 4.3 times the daily average, respectively. The health risks that this entails could mean that astronauts would be suffering from radiation-related health problems before they even arrive on Mars, to say nothing of the surface operations or return trip.
Luckily, there are mitigation strategies for the transit and surface parts of the mission, some of which Biswal and Annavarapua recommend. “We are currently developing a Mars subsurface habitat that could address all the health-related issues on the extended mission or permanent settlement on Mars,” said Biswal. “[T]he crewed mission should include faster production of crew necessities from in-situ resource [utilization] (ISRU).”
An illustration of a moon base that could be built using 3-D printing and ISRU, in-situ resource utilization. Credit: RegoLight, visualisation: Liquifer Systems Group, 2018
This proposal is in keeping with the many mission profiles that NASA and other space agencies are developing for future lunar and Martian exploration. There are already many existing strategies to keep crews protected from radiation while in space, but in extraterrestrial environments, all concepts incorporate the use of local resources (such as regolith or ice) to create natural shielding.
The local availability of ice is also seen as a must for the sake of ensuring a steady water supply for human consumption and irrigation (since astronauts on long-duration missions will need to grow much of their own food). Aside from all that, Biswal and Annavarapu emphasized how maintaining a fast flight and return trajectory will help reduce travel time.
There is also the possibility of leveraging advanced technologies like nuclear-thermal and nuclear-electric propulsion (NTP/NEP). NASA and other space agencies are actively researching nuclear rockets since a spacecraft equipped with NTP or NEP could make the journey to Mars in just 100 days. But as Bisawl and Annavarapu indicated, this raises the challenge of dealing with nuclear systems and more exposure to radiation.
Alas, all of these challenges can be addressed with the right combination of innovation and preparation. And when you consider the payoffs of sending crewed missions to Mars, the challenges seem a lot less daunting. As Biswal offered, these include proximity, the opportunities to study Martian soil samples in an Earth laboratory, the expanding of our horizons, and the ability to answer fundamental questions about life:
“We have always been fascinated to know where we have come from and if there is any life like us in other astronomical bodies? [W]e cannot execute a crewed mission to any other interplanetary destination due to mission risk and management.
“Mars is the only neighboring planet in our solar system we can explore, it [has] a good geologic record to answer all [of] our unsolved questions, and [we can] bring samples [back] to analyze in our terrestrial lab?” And finally, it would be interesting to execute a human mission to Mars in order to demonstrate the extent of current technology and aerospace progression.”
Artist’s concept of a bimodal nuclear rocket making the journey to the moon, Mars, and other destinations in the solar system. Credit: NASA
Since the early 1960s, space agencies have been sending robotic missions to Mars. Since the 1970s, some of those missions have been landers that set down on the surface. With the over forty years of data and expertise that’s resulted, NASA and other space agencies are now looking to apply what they’ve learned so they can send the first astronauts to Mars.
The first attempts may still be over a decade (or more) away, but only if significant preparations take place beforehand. Not only do a lot of mission-related components and infrastructure still need to be developed, but a lot of research still needs to be done. Thankfully, these efforts benefit from the kinds of thorough assessments we see here, where all potential risks and hazards are investigated (and counter-measures proposed).
All of this will hopefully lead to the creation of a sustainable program for Martian exploration. It might even enable the long-term human occupation of Mars and the creation of a permanent colony. Thanks to the efforts of many researchers and scientists, the day may finally come when there is such a thing as “Martians.”
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Every challenge astronauts will face on a flight to Mars (2021, February 5)
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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.
That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.
“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”
The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.
Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.
Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.
Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.
Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.
Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.
“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”
The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.
North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.
Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”
Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.
Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.
For Dello, the “fingerprints of climate change” were clear.
“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”
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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.
On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.
They call it “Big Sam.”
The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.
It didn’t die alone.
“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.
She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”
“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.
The head alone, she said, is about the size of a baby elephant.
The discovery was a long time coming.
The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.
“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.
When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”
“It contains about 100 to 300 bones per square metre,” she said.
Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.
About a year ago, they found the second adult: Big Sam.
Bamforth said both dinosaurs are believed to have been the elders in the herd.
“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.
“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”
The genders of the two adults are unknown.
Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.
The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.
She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.
“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.
“It’s pretty exciting.”
This report by The Canadian Press was first published Sept. 25, 2024.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
