The thread for space cadets!

[uppi]

If you asked the question, you already know the answer.

Maybe I will be pleasantly surprised one day?

 

[Imaus]

India conducted a successful anti-satellite test today.

Pakistan does a parade, India shoots down a Sat. Better that than a shooting war, at least

I thought there might be a discussion about sexist space suits going on in here. Alas, no.

There's not much to discuss, suits are hard to manufacture and come by. The fact that they don't have two medium suits on hand while having multiple personnel who can only fit in medium suits is worrying, but NASA is probably betting on the Soyuz escape capsule or shutting off sections of the ISS if anything goes wrong ala MIR, and anything more is a out-of-context problem as far as they're concerned.

Maybe I will be pleasantly surprised one day?

The NSC has no real power, Pence is grandstanding. Even with 21 Bil this year, NASA needs more. While I do think they will rush a few manned projects forward - 2028 IS unacceptable - nothing will come out of that speech alone; it's just part of the 'oh the SLS is outdated already and over schedule and over budget oh gods oh fudge' scramble of late.

 

[hobbsyoyo]

Bridenstine came out and said they won't be launching Orion on a Falcon Heavy after all. He was bluffing. Pence is bluffing. Neither of them have the backing of Congress to increase funding to levels required to get this job done nor reign in Boeing on the SLS. The only way they can advance the schedule is if they can convince Boeing to spend their own money to speed things up and by taking potential dangerous shortcuts in the qualification of the rocket for flight. They are floating the idea of doing a full-duration hotfire of the rocket to save a few months of schedule but that will put either the rocket, the launchpad or both at risk.

 

[Berzerker]

https://phys.org/news/2019-03-million-year-old-deathbed-linked-dinosaur-killing-meteor.html

On a branch of an inland sea in North America - N Dakota to be specific - a rather unique situation gave us the best find to date showing how animals died when a 6-mile wide chunk of rock from space killed off 75% of life on the planet 66 million years ago.

The impact on the northern Yucatan peninsula generated massive quakes that sent shock waves around the world possibly magnifying or resuming eruptions of lava in India's Deccan Traps region and tsunamis even on bodies of water far from the ocean.

In North Dakota a large inland sea began sloshing back and forth dumping fish and marine life up onto the shore at about the same time rock melted by the impact was falling from the sky. These little bullets - tektites, spherules - rained down igniting fires and becoming embedded in animals and trees at speeds of 100-200 mph.

Some of these missiles hit trees and became surrounded by amber, they're the best unaltered samples of material from the impact found so far. Some fish lived long enough for these melted pieces of debris to lodge in their gills and feeding mechanisms only to be buried minutes later by another tsunami's sediments and gravel.

 

[hobbsyoyo]

Thanks for sharing that, it's awesome!

 

[Berzerker]

yw

this one aint that interesting but it raises questions that are:

https://phys.org/news/2019-03-sun-magnetic-field-ten-stronger.html

Okay, how in the hell can we be sure about most of the stuff we think we know if we were off by a factor of 10 about our own sun's magnetic field?

 

[uppi]

Okay, how in the hell can we be sure about most of the stuff we think we know if we were off by a factor of 10 about our own sun's magnetic field?

It is not like there is an easy way to measure the magnetic field in the corona of the sun. Most likely the scientists in the field knew that the old number was highly questionable.

It is a long-running joke that in astrophysics the error bars are on the orders of magnitude. In such cases, being only off by a factor of 10 is actually an accomplishment

 

[Kaitzilla]

https://phys.org/news/2019-03-million-year-old-deathbed-linked-dinosaur-killing-meteor.html

On a branch of an inland sea in North America - N Dakota to be specific - a rather unique situation gave us the best find to date showing how animals died when a 6-mile wide chunk of rock from space killed off 75% of life on the planet 66 million years ago.

The impact on the northern Yucatan peninsula generated massive quakes that sent shock waves around the world possibly magnifying or resuming eruptions of lava in India's Deccan Traps region and tsunamis even on bodies of water far from the ocean.

In North Dakota a large inland sea began sloshing back and forth dumping fish and marine life up onto the shore at about the same time rock melted by the impact was falling from the sky. These little bullets - tektites, spherules - rained down igniting fires and becoming embedded in animals and trees at speeds of 100-200 mph.

Some of these missiles hit trees and became surrounded by amber, they're the best unaltered samples of material from the impact found so far. Some fish lived long enough for these melted pieces of debris to lodge in their gills and feeding mechanisms only to be buried minutes later by another tsunami's sediments and gravel.

Wow, 6 miles wide and 45,000 mph.
The asteroid that killed the dinosaurs boggles the mind.
Have we named it yet?

Too big to cause a mushroom cloud, the debris formed a suborbital rooster tail.
Pieces landed on all the moons in the solar system and Mars too.
https://www.newyorker.com/magazine/2019/04/08/the-day-the-dinosaurs-died

More than 99.9999 per cent of all living organisms on Earth died, and the carbon cycle came to a halt.
Earth itself became toxic.

150 mph molten glass beads falling 1000 miles away.
70% of the world's forests were set on fire eventually.

 

[Berzerker]

the new yorker article says the inland sea was actually a seaway linked to the Gulf which I presume means the Yucatan splashdown had a direct line for tsunamis

 

[Kaitzilla]

the new yorker article says the inland sea was actually a seaway linked to the Gulf which I presume means the Yucatan splashdown had a direct line for tsunamis

I think the inland sea in North Dakota sloshed back and forth from the earthquakes and it was this sediment that caught all the falling stuff from the impact.
The tsunami arrived hours later and added more stuff on top?

Ya, North Dakota was a direct line for the tsunami to reach.

After the G.S.A. talk, DePalma realized that his theory of what had happened at Tanis had a fundamental problem. The KT tsunami, even moving at more than a hundred miles an hour, would have taken many hours to travel the two thousand miles to the site. The rainfall of glass blobs, however, would have hit the area and stopped within about an hour after the impact. And yet the tektites fell into an active flood. The timing was all wrong.

This was not a paleontological question; it was a problem of geophysics and sedimentology. Smit was a sedimentologist, and another researcher whom DePalma shared his data with, Mark Richards, now of the University of Washington, was a geophysicist. At dinner one evening in Nagpur, India, where they were attending a conference, Smit and Richards talked about the problem, looked up a few papers, and later jotted down some rough calculations. It was immediately apparent to them that the KT tsunami would have arrived too late to capture the falling tektites; the wave would also have been too diminished by its long journey to account for the thirty-five-foot rise of water at Tanis. One of them proposed that the wave might have been created by a curious phenomenon known as a seiche. In large earthquakes, the shaking of the ground sometimes causes water in ponds, swimming pools, and bathtubs to slosh back and forth. Richards recalled that the 2011 Japanese earthquake produced bizarre, five-foot seiche waves in an absolutely calm Norwegian fjord thirty minutes after the quake, in a place unreachable by the tsunami.

Richards had previously estimated that the worldwide earthquake generated by the KT impact could have been a thousand times stronger than the biggest earthquake ever experienced in human history. Using that gauge, he calculated that potent seismic waves would have arrived at Tanis six minutes, ten minutes, and thirteen minutes after the impact. (Different types of seismic waves travel at different speeds.) The brutal shaking would have been enough to trigger a large seiche, and the first blobs of glass would have started to rain down seconds or minutes afterward. They would have continued to fall as the seiche waves rolled in and out, depositing layer upon layer of sediment and each time sealing the tektites in place. The Tanis site, in short, did not span the first day of the impact: it probably recorded the first hour or so. This fact, if true, renders the site even more fabulous than previously thought. It is almost beyond credibility that a precise geological transcript of the most important sixty minutes of Earth’s history could still exist millions of years later—a sort of high-speed, high-resolution video of the event recorded in fine layers of stone. DePalma said, “It’s like finding the Holy Grail clutched in the bony fingers of Jimmy Hoffa, sitting on top of the Lost Ark.” If Tanis had been closer to or farther from the impact point, this beautiful coincidence of timing could not have happened. “There’s nothing in the world that’s ever been seen like this,” Richards told me.

Inland sea seen at 1:30
Guess that picture from 66 million years ago explains the fossils in my back yard as a kid.

The yellow numbers are wave height in meters striking land.

 

[Berzerker]

thats true, even at the speed of a jet airliner it would have taken several hours to reach N Dakota but shockwaves would have taken much less time

 

[Kaitzilla]

thats true, even at the speed of a jet airliner it would have taken several hours to reach N Dakota but shockwaves would have taken much less time

It is very interesting reading.
Right before the impact, the atmosphere had 1000ppm of carbon dioxide and the ocean levels were much higher and the world was much warmer.
We are at 400ppm and rising 2ppm per year.

To get back to "where did Florida, the coasts, and the middle of the USA go?" levels, it should take 1000-400 = 600/2 = 300 years.
Thankfully, this will settle the question of whether carbon dioxide really warms the planet decisively.

I hope NASA is watching out for 6 mile wide asteroids as life was still fine, if more crowded, until the rock hit.


Also something to ponder, does 1000ppm of carbon dioxide or higher make people literally dumber?
https://thinkprogress.org/exclusive...gnition-new-harvard-study-shows-2748e7378941/

 

[Berzerker]

I missed the 1,000 ppm in the article, do they have a measure for the layer deposited by impact debris? I imagine there's one helluva spike representing the KT boundary.

We lost a good chunk of Florida about 125-115kya during a warm period as seas were several meters higher back then.

 

[Kaitzilla]

I missed the 1,000 ppm in the article, do they have a measure for the layer deposited by impact debris? I imagine there's one helluva spike representing the KT boundary.

We lost a good chunk of Florida about 125-115kya during a warm period as seas were several meters higher back then.

Oops, sorry I looked up the CO2 levels in the late Cretaceous Period (100 million to 66 million years ago)
https://phys.org/news/2013-09-late-cretaceous-period-ice-free.html

"Currently, carbon dioxide levels are just above 400 parts per million (ppm), up approximately 120 ppm in the last 150 years and rising about 2 ppm each year," said Ken MacLeod, a professor of geological sciences at MU. "In our study, we found that during the Late Cretaceous Period, when carbon dioxide levels were around 1,000 ppm, there were no continental ice sheets on earth. So, if carbon dioxide levels continue to rise, the earth will be ice-free once the climate comes into balance with the higher levels."

I'm not sure how much the asteroid spiked the concentration with 1 trillion tons of CO2 and 10 billion tons of methane.
Humans add 30 billion tons of CO2 I think?
So the asteroid is about 33 years of human CO2 emissions.
It also halted the entire carbon cycle by killing everything, so the yearly graph stopped bouncing up and down.

When the asteroid struck, it vaporized layers of limestone, releasing into the atmosphere a trillion tons of carbon dioxide, ten billion tons of methane, and a billion tons of carbon monoxide; all three are powerful greenhouse gases. The impact also vaporized anhydrite rock, which blasted ten trillion tons of sulfur compounds aloft. The sulfur combined with water to form sulfuric acid, which then fell as an acid rain that may have been potent enough to strip the leaves from any surviving plants and to leach the nutrients from the soil.

Today, the layer of debris, ash, and soot deposited by the asteroid strike is preserved in the Earth’s sediment as a stripe of black about the thickness of a notebook. This is called the KT boundary, because it marks the dividing line between the Cretaceous period and the Tertiary period. (The Tertiary has been redefined as the Paleogene, but the term “KT” persists.) Mysteries abound above and below the KT layer. In the late Cretaceous, widespread volcanoes spewed vast quantities of gas and dust into the atmosphere, and the air contained far higher levels of carbon dioxide than the air that we breathe now. The climate was tropical, and the planet was perhaps entirely free of ice. Yet scientists know very little about the animals and plants that were living at the time, and as a result they have been searching for fossil deposits as close to the KT boundary as possible.

Not surprised about Florida.
The entire state is flat and the highest point is some hill 300 feet above sea level.
It is rising sea level bait.

 

[hobbsyoyo]

I don't have high confidence that we would spot a planet-killer before it hit. We've had recent high-profile impacts like Chelyabinsk that came out of nowhere. Even though they were smaller rocks, they were still big enough to take down a city had the impact angles been different. There are lots and lots of 6-mile asteroids out there and while I could go along with the notion that we've spotted most of them, we haven't spotted them all.

We are protected in large part by the extremely low odds of any two objects colliding in space but we're playing a numbers game right now that we will lose given enough time. This is one area I believe a Space Force should play a large role in. NASA is awesome but no one gets funded like the military and this is a big enough threat that it is worth devoting serious resources too.

 

[red_elk]

I doubt we could do anything about it even if we spotted it. Unless it's not too big and we have a couple of decades to prepare.

 

[Cutlass]

I don't have high confidence that we would spot a planet-killer before it hit. We've had recent high-profile impacts like Chelyabinsk that came out of nowhere. Even though they were smaller rocks, they were still big enough to take down a city had the impact angles been different. There are lots and lots of 6-mile asteroids out there and while I could go along with the notion that we've spotted most of them, we haven't spotted them all.

We are protected in large part by the extremely low odds of any two objects colliding in space but we're playing a numbers game right now that we will lose given enough time. This is one area I believe a Space Force should play a large role in. NASA is awesome but no one gets funded like the military and this is a big enough threat that it is worth devoting serious resources too.

Military may have more money. But they are steadily getting worse at using it efficiently.

https://www.rollingstone.com/politics/politics-features/pentagon-budget-mystery-807276/

 

[Imaus]

Sure, we can catalog and even move ECAs into stable orbits for exploitation and safety. It demands, however, at the least: Nuclear Thruster Propulsion, and a lot of it, extensive ISRU, a huge manned presence in space in the dozens at least, swarms of robot re-purposed mosquito ISRU extractors, and decades of work. It could be done; but it will require huge commitment, specie, and will.

As many scifi stories posit, it'll only be undertaken seriously once a city is wiped off the map; or even a country. Most people just don't see a threat. I bet a few are just comparing this to 1908, no one died, we don't have to worry until 210x/211x; yadda yadda.

 

[red_elk]

Rare picture of last year's lunar eclipse. The photographer took a good moment.

Spoiler :

 

[hobbsyoyo]

This meme is very true: