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Earth from Space: The Amazon plume
29/03/2024

The Copernicus Sentinel-3 mission takes us over northern Brazil, where the Amazon River meets the Atlantic Ocean.

Originating in the Andes, the Amazon River flows east, traversing six South American countries before reaching the northeast coast of Brazil, where it empties into the Atlantic. The sediment-laden river appears brown as it flows to the open ocean in the upper centre of the image.

The coast is surrounded by a muddy-brownish plume of suspended sediment, carried from upstream to the maze of channels constituting the 270-km-wide mouth of the Amazon. Discharge from the Amazon River, the Amazon plume, accounts for around 20% of the global input of freshwater into the ocean from Earth's land surfaces.

The Amazon has over 1000 tributaries, some of which are visible as thin, winding lines entering the river from the south, including the Tapajos River to the west and, further downstream, the Xingu River. The dark colour of these sediment-poor tributaries contrasts with the brownish sediment-rich Amazon waters.

The Tapajós-Xingu area is an important moist forest ecoregion. However, the Transamazon Highway, discernible as a brown line traversing this area, has spurred urbanisation.

The colour of the land varies, ranging from the deep green of dense, untouched vegetation to various tones of brown, highlighting the contrast between the rainforest and sprawling cultivation  ̶  the fishbone-like patterns particularly visible along the highway.

Light green hues across the image denote agricultural areas, which were once covered by rainforest. The somewhat geometric shapes, which appear dark green and brown, result from forest clear-cutting.

Rainforests worldwide are disappearing at an alarming rate, a matter of great concern owing to their pivotal role in the global climate, and their status as habitats for a wide range of plants, animals and insects.
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Yaogan 30 is probably finished.
A new series may begin.
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Spaceflight Entertainment and Hobbies / Re: Space Stamps
« Last post by salyut on Today at 08:42 am »
November, 1966, Qatar.
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Advanced Concepts / Re: General Hypersonic Flight Related Topics
« Last post by Star One on Today at 08:39 am »
Quote
HUNTSVILLE, Ala. — The U.S. Navy is heading into a major test of a hypersonic weapon that will help determine the way ahead for a joint development program with the U.S. Army, according to the Army’s Rapid Capabilities and Critical Technologies Office director.
“The Navy is moving forward on their test, which isn’t a launch out of ground support equipment, but just off a stool launch, so we get another look at the missile,” Lt. Gen. Robert Rasch told Defense News in a March 27 interview here at the Association of the U.S. Army’s Global Force Symposium.



Quote
The test in the spring is focused solely on missile performance and is conducted using a test stand that eliminates ground support equipment, canister and launcher.
“It’s more of a command to the missile to ignite and watch the missile go through stage one, stage two, payload adapter, hypersonic glide body separating and do its thing,” Rasch said.
The test is to ensure the services understand the missile performs as intended, he said.

https://www.defensenews.com/digital-show-dailies/global-force-symposium/2024/03/28/us-navy-preps-hypersonic-weapon-test-this-spring-with-army-watching/?utm_source=sailthru&utm_medium=email&utm_campaign=dfn-dnr
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There are several of us, convinced by the math, that "no part" isn't going to work for RCS.

We saw indications of gaseous RCS system circa Jun-2021. Their removal appears to have been a tactical step.
(Edit: Both for SS and SH. Whether the current design is similar is anyone's guess.)
See discussion:
https://twitter.com/elonmusk/status/1407969457411067905

So the hot-gas thrusters have been:
- Added for Starship flip
- Removed for Starship flip (Raptors only)
- Re-added for Starship in-orbit ops (and possibly Lunar Starship)
- Added to Super Heavy
- Removed from Super Heavy
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General Discussion / Re: Flight crew assignments
« Last post by marcdrnl on Today at 07:35 am »
The page is up to date, Peskov is part of increment 73.
If a Roscosmos/NASA agreement is found, Peskov will simply fly on Dragon, otherwise he will fly on Soyuz.

Pettit isn't mentioned on Soyuz MS-26 as TC, O'Hara and Rubio were. Gorbunov isn't said to fly on Crew-9 as Borisov and Grebyonkin were
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The number might be Y50.
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General Discussion / Re: Flight crew assignments
« Last post by vp. on Today at 07:22 am »
The page is up to date, Peskov is part of increment 73.
If a Roscosmos/NASA agreement is found, Peskov will simply fly on Dragon, otherwise he will fly on Soyuz.
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Space Science Coverage / Re: ESA - Voyage 2050
« Last post by Hobbes-22 on Today at 07:10 am »
I had this discussion with my congressman at the time Jim Sensenbrenner (former chair of the House Science Committee).  We were discussing the ITER nuclear fusion project.  He thought, and I agreed, that committing to a design thirty years to complete was completely ridiculous and a big waste of money because it ignores potential breakthroughs along the way.  I think it is reasonable to come up with general goals for twenty years out, but not specific designs to accomplish them.

We're at a point where projects as complicated as ITER take 20 years to build. The start of that build is when you should freeze the design, otherwise you'll be restarting construction and adding years to the build over and over again.

Before that, there's going to be years of designing, and before that, there's going to be years of R&D before you can settle on a design. We could speed that up by increasing funding, but as we've seen with ITER, that's not happening. So we end up with having to freeze the design 30 years before the reactor becomes operational.
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