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Earth is shielded against stellar explosions, and only a nearby stellar explosion would destroy Earth.
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Astronauts enroute to Mars, with less atmospheric protection would face greater risk.
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A supernova within several hundred light years would greatly damage Earth. How close a stellar event could a Martian trip survive ?
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A supernova so close that it would seriously affect astronauts would have to be extremely close. Gamma Ray bursters occur so rarely that we measure every event in every galaxy for billions of "near by" galaxies. A gamma ray burst is a much more energetic event than a supernova, but even a supernova is extremely rare. A supernova close enough to affect astronauts is so unlikely that it's more likely an asteroid would hit Earth and cause extinction of all life sometime between now and launch of the Mars trip.
If you want to worry about dangers, a real danger would be a solar flair sending a burst of radiation in the direction of a spaceship before it lands. Mars has atmosphere to reduce such radiation, and bags filled with regolith or water on the roof of the habitat would protect against the rest. If the solar radiation hit at night then the bulk of Mars itself would provide complete protection. Interplanetary space would have only the protection of the spacecraft itself.
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That has been my impression also, that a solar flare could wipe out the Mars team, in the spacecraft, before they even reached Mars.
That is why I suggested (in an earlier thread) that we may be able to mitigate the danger with the following idea (as strange as it may sound at first):
Cover the spacecraft in some way with the eventual Mars habitats. The spacecraft would be inside a bubble. The bubble could be filled with a gas or liquid (perhaps water) that would help to protect the occupants.
When the craft arrives on Mars, the protective envelope surrounding the craft is removed and used as habitats etc on the surface, it has served two purposes. I realize that the outside envelope may need repairs by the time they get to Mars, however, that is desirable to the alternate scenerio.
Well, what do you think?
PLIND ???
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Although a solar flare is a nasty thing, its not quite that nasty... a TransHab is the most likly habitation module concept for a Mars mission, and it has a void filled with a light foam between its inner pressure wall and outter impact wall. A layer of water 6-12in thick, possibly backed up by hydrogen or boron doped polymer sheeting, would protect well enough against most radiation, and you could maybe drink this water too.
As for a flare, a fairly thick wall of Aluminum, augmented by more water or more H2-HDPE/B-HDBE, would compose the center of the rigid structure of the TransHab, and would stop a solar flare cold. Another technique to help would be to use a powerful magnet around the inner storm cellar, which would deflect the charged particles that make up solar flares, though this might be hard to work into the design. On a side note, the VASIMR plasma rocket produces such a field inherintly which would envelope the ship.
Ultimatly, radiation isn't such a huge problem IN the hab, provided you can carry enough shielding with you. To further cut the dose when the crew isn't active, they could even sleep in the storm cellar at "night".
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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A supernova within several hundred light years would greatly damage Earth. How close a stellar event could a Martian trip survive ?
*Well, supernovae don't just happen overnight, as you probably already know. Astronomers have already identified and are keeping tabs on stars in a pre-supernova state. Some of these are hundreds of thousands if not millions of light-years away.
Based on my daily reading at various astronomy sites, there are no stars (perhaps with the exception of Eta Carina) within our vicinity "about to blow," which could adversely affect us or Marsian astronauts.
I'll stand corrected on this, of course; I'm not a pro.
I hope this helps.
--Cindy
::EDIT:: Besides solar flares, there will also be coronal mass ejections to deal with (I'd be more concerned about the CME's, as they are much more powerful).
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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Sitting atop an asteroid would provide protection from 2 pi stradians (half the sky). Burrowing would give near complete radiation protection.
Many NEOs are resource rich (water, organic compounds, metals), so NEO mines could help pay the cost of a habitat on an asteroid.
There are 3 possible orbital periods that may be useful for Earth Mars cyclers.
3/2 and 5/4 year orbits are nearly resonant with both Earth and Mars (these orbits are called the Niehoff VISIT 2 and VISIT 1 cycler orbits). Earth rendesvous could be every 3 years or every 5 years. Mars rendesvous could be every 7.5 years or every 3.75 years
2.2 year orbits where the cycler crosses the earth orbit twice approx
2 pi/7 radians apart is the Aldrin cycler. It would rendesvous with earth and Mars every synodic period (about 2 1/7 years)
There are already asteroids that approximate orbits mentioned above.
Here is one: http://clowder.net/hop/2000YJ11.html]ht … 0YJ11.html
Hop's [url=http://www.amazon.com/Conic-Sections-Celestial-Mechanics-Coloring/dp/1936037106]Orbital Mechanics Coloring Book[/url] - For kids from kindergarten to college.
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An astronomer suggested that there are no Aliens visiting us because Gamma Ray Bursts destroyed them.
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During a close stellar explosion event, cave dwellers on Mars would have their own air, while Earth dwellers would have their atmosphere blown away.
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An astronomer suggested that there are no Aliens visiting us because Gamma Ray Bursts destroyed them.
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During a close stellar explosion event, cave dwellers on Mars would have their own air, while Earth dwellers would have their atmosphere blown away.
And gamma ray bursts aren't really two black holes colliding in a far off galaxy, they're the exhaust from an alien interstellar spaceship which only appears to be a burst as its tail pipe points this way. Earth was terraformed and colonized billions of years ago by Martians who escaped their dieing planet. And extinction of the dinosaurs wasn't caused by an asteroid impact off the Yucatán peninsula; it was a world war of the velociraptors.
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I don't think we've ever witnessed a GRB (gamma-ray burst) close enough to be remotely harmful. Correct me if I'm wrong, though.
The only thing we really need to worry about is a nasty solar flare, as was mentioned above.
[url=http://nightskylive.com]Night Sky Live Project[/url]
[url=http://apod.nasa.gov]Astronomy Picture of the Day[/url]
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Only the paranoid will survive.
Gambler's luck did not protect the Aliens who are overdue on their trip to visit us.
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What if a nearby black hole sucks up a failed sun, both undetected until it is too late ?
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Worth looking at an old topic in an older thread
Astronomers observed the brightest flash of light ever seen
2.4 billion light years from Earth Gamma Ray Burst likely triggered by the formation of a black hole
https://www.france24.com/en/live-news/2 … -ever-seen
,
https://phys.org/news/2022-10-record-br … osion.html
,
https://spacepub.org/news/nasas-fermi-a … smic-blast
some other old discussions of Gamma Ray Bursts on newmars forums
Gamma ray bursts point to dark matter source?
https://newmars.com/forums/viewtopic.php?id=5201
,
New Discoveries #5 - Deep space, galactic, solar system, etc. Palomar had many otehr topics dedicated to cosmology
https://newmars.com/forums/viewtopic.php?id=3313
Last edited by Mars_B4_Moon (2022-10-18 06:24:36)
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A supernova warning sign: When massive stars dim
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How Dangerous are Nearby Supernovae to Life on Earth?
https://www.universetoday.com/158316/ho … -on-earth/
Life and supernovae don’t mix.
From a distance, supernovae explosions are fascinating. A star more massive than our Sun runs out of hydrogen and becomes unstable. Eventually, it explodes and releases so much energy it can outshine its host galaxy for months.
But space is vast and largely empty, and supernovae are relatively rare. And most planets don’t support life, so most supernovae probably explode without affecting living things.
But a new study shows how one type of supernova has a more extended reach than thought. And it could have consequences for planets like ours.
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NASA’s Webb Telescope Captures Rarely Seen Prelude to Supernova
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Object mistaken as a galaxy is actually a black hole pointed directly at Earth
https://www.livescience.com/object-mist … y-at-earth
The brightest gamma-ray in human history hit our planet this past Fall
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Brightest Gamma-ray Burst Shines Light on Milky Way Structure
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You Don't Want to Be Within 160 Light-Years of a Supernova
https://www.universetoday.com/161113/yo … supernova/
Supernovae are incredibly common in the universe. Based on observations of isotopes such as aluminum-26, we know that a supernova occurs on average about every fifty years in the Milky Way alone. A supernova can outshine a galaxy, so you wouldn’t want your habitable planet to be a few light years away when it goes off. Fortunately, most supernovae have occurred very far away from Earth, so we haven’t had to concern ourselves with wearing sunscreen at night. But it does raise an interesting question. When it comes to supernovae, how close is too close? As a recent study shows, the answer depends on the type of supernova.
There is geological evidence that supernovae have occurred quite close to Earth in the past. The isotope iron-60 has a half-life of just 2.6 million years, and it has been found in ocean floor sediment laid down about 2 million years ago. It has also been found in Antarctic ice cores and lunar regolith, suggesting a supernova event around that time. Samples of Earth’s crust point to evidence of another supernova event around 8 million years ago. Both of these would likely have occurred within a few hundred light years of Earth, perhaps as close as 65 light years. Neither of these supernovae seems to have triggered a planet-wide mass extinction, so you might think any supernova more distant than 100 light years is harmless.
What to Know About Lunar Gateway, NASA’s Future Moon-Orbiting Space Station
https://news.yahoo.com/know-lunar-gatew … 25614.html
NASA, along with a suite of international and private partners, has big plans to build a small space station. Called Lunar Gateway, the proposed outpost will support missions at and around the Moon
Last edited by Mars_B4_Moon (2023-04-29 02:49:04)
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‘It’s new territory’: why is Betelgeuse glowing so brightly and behaving so strangely?
https://www.theguardian.com/science/202 … -strangely
When Will Betelgeuse Explode?
https://www.discovermagazine.com/the-sc … se-explode
The big, red galactic troublemaker has kept humanity guessing for thousands of years.
Last edited by Mars_B4_Moon (2023-05-26 19:01:54)
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A very far distance, 21 million light-years 6.4 megaparsecs and no danger but Something to see if you have an Amateur Telescope or even good Binoculars.
'How to see the new supernova in the Pinwheel Galaxy'
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Betelgeuse is Almost 50% Brighter Than Normal. What’s Going On?
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Betelgeuse, Alpha Orionis, at the Evolutionary stage of Red supergiant HD 39801, SAO 113271, HIP 27989, acting strange again.
The star Betelgeuse is continuing to behave mysteriously
' has shown some unexpected behavior'
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here's what would happen if it exploded
https://phys.org/news/2023-06-betelgeus … yhere.html
If Betelgeuse does go supernova, what would it look like? The star is around 500 light years away. Following an explosion, we first would detect a rain of massless particles called neutrinos, which would be harmless to us. After that, the star would quickly brighten.
After one or two weeks it would shine with about the same brightness as the full Moon. Betelgeuse would then fade over the next several months but remain visible in the day time for six to 12 months. At night, you should be able to see it with the naked eye for another one or two years. But after that, we would never see it again—Orion would forever lose its red sparkle.
Is there any danger to us? Supernovas produce high energy particles called cosmic rays, which can get past the shield of the Earth's magnetic field. But the amounts would be small compared to other radiation we receive for all but the nearest supernovas.
A supernova explosion would also create radioactive iron. In fact this substance has been found in Earth's seabed and on the Moon, believed to have formed in a supernova explosion between 2 and 3 million years ago. That supernova was perhaps 300 light years from us, closer than Betelgeuse, but far enough to cause no major problems for life on Earth.
A very close supernova, closer than 30 light years, could cause major problems: the cosmic rays could cause ozone destruction and dangerous UV levels on Earth. It could reduce ozone by half over a period lasting hundred to thousands of years: this level is considered capable of causing an extinction event. But such a close supernova would be very rare, and may happen only once per billion years.
Last edited by Mars_B4_Moon (2023-06-17 16:46:24)
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What’s the Link Between Gamma Ray Bursts and Supernovae? It Might Be Binary Stars
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Far, far away, about 55 million light-years
M87's Jet is Triggering Novae
https://www.universetoday.com/163568/m8 … ing-novae/
M87 also features a massive jet of plasma blasting out into deep space from the galactic core. These phenomena: the jet and the novae, are unrelated astronomical occurrences, or so scientists believed. But astronomers recently discovered that the novae in M87 seem to be uncharacteristically aligned along the jet, instead of scattered randomly throughout the galaxy. Is the jet somehow triggering nova explosions?
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How Close is Too Close to a Kilonova?
https://www.universetoday.com/163849/ho … -kilonova/
Cataclysmic events happen in the Universe all the time. Black hole mergers, supernovae, gamma-ray bursts, and a whole host of others. Most of them happen in distant galaxies, so they pose no threat to us. But there are a few that could affect life on Earth, and a couple could even pose an existential threat. One of these threats is known as a kilonova.
There are three main threats from a kilonova explosion. The first is the X-ray emission from the afterglow of the event, which generally emanates from the polar region. Given the decrease in light intensity with distance, the team calculated it would pose a threat to a range of 5 parsecs, or about 16 light-years. The second threat is from the gamma rays produced by the explosion itself. Since gamma rays tend to scatter strongly off interstellar particles, they only pose a threat to 4 parsecs or 13 light-years.
The third threat is more subtle. The first two would reach us at the speed of light, and if we were outside their threat radius we would see them only as an amazing light show. But the shock wave of the kilonova would create an expanding shell of high-energy cosmic rays. These could reach us a thousand years or more after the initial X-rays and gamma-rays. When the team calculated the lethal range of cosmic rays, they found it was nearly 36 light-years. So a nearby cosmic light show from a kilonova could be a warning of our imminent demise.
Last edited by Mars_B4_Moon (2023-10-23 17:29:02)
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A very unlikely event but with Cosmic Rays and Amaterasu particle making the news
There was an event named 'Oh-My-God particle' the particle's energy was unexpected and called into question prevailing theories, 200 times higher than the highest collision energy of the Large Hadron Collider. Scientific studies using the Telescope Array Project have suggested a source of the particles within a 20 degree radius "warm spot" in the direction of the constellation Ursa Major, the Ameratsu particle appears to have emerged from the Local Void, an empty area of space bordering the Milky Way galaxy.
https://web.archive.org/web/20231124093 … g-to-earth
https://web.archive.org/web/20230708064 … -20150514/
https://web.archive.org/web/20220412155 … -particles
https://web.archive.org/web/20231124121 … %20Science.
Last edited by Mars_B4_Moon (2023-11-26 22:23:20)
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