Orbital debris reentry

Not intending to add things for readers to worry about. But it is interesting to note that meteoric infall (rocks) is about 50 tons per day, and infall from increased orbital satellites (mostly aluminum) may increase to 2 tons per day.

Air pollution from reentering megaconstellation satellites could cause ozone hole 2.0 | Space

https://www.nature.com/articles/s41598-021-89909-7?utm_medium=affiliate&utm_source=commission_junction&utm_campaign=3_nsn6445_deeplink_PID100052171&utm_content=deeplink

==
Rocks from out yonder contain not much aluminum, but earth crustal rocks do. This is why we have aerospace and beer cans, following invention of electrical refining. But the 'teach' here is that earth crust has minerals that did not sink to the core, back when that happened. Al minerals are among the floaters.

 

Militarily targeting starlink
Chinese Researchers Publish Strategy to Destroy Elon Musk's Starlink
This sounds most unwise.

 

It's that time again ... The second part of Chinese space station has been launched. The particular rocket used for this is unusual in that its core (first) stage goes into orbit .. and falls back out after weeks or months. That is about 20 tons empty of fuel and without capability for aimed re entry. That is a big thing for uncontrolled re entry nowadays.

It has just now made the watch list:

https://aerospace.org/reentries?field_reentry_type_target_id%5B%5D=33&field_reentry_sighting_value=All&sort_by=field_predicted_reentry_time_value&sort_order=DESC&format_select=tiles&reentry_timezone_selector=UTC

They are currently predicting July 31 re entry but +/- a lot. Typically their re entry predictions tighten up over time. So watch that space.

 

please explain 2.2 tonnes

 

OK thanks. I do not know which rocket bodies have downward thrusters to aim them when de orbiting time comes. CZ-5B does not, and because of media coverage I presume it is the largest thing that does not.

 

This may be the most efficient page to watch:

https://aerospace.org/reentries/cz-5b-rb-id-53240

and links there provide some background info.

For completeness on topic, another launch like this one will happen before end of year. Bringing third and final segment to this station. And resulting in another down goer.

Unmanned launches (only) happen from Wenchang in Hainan. It is uniquely in China the place where civilians (you'll need a visa ) can watch the show. Hotels rooftops and a beach 8 km from the launch site allow viewing.

 

Re entry prediction by Aerospace.org has tightened up to

30 Jul 2022 18:16 UTC ± 5 hours

Ten hrs overall means about 7 orbits which further means there is a lot of area where it cannot come down. Assuming Aerospace.org is correct. Remaining target areas can be seen in link in #32.

 

no one ever double posts intentionally

 

Re entry point has been reported at 119 East, 9.1 North. This is in the South China Sea, on the Philippines side. No report of chunks on land seem to have appeared.

 

Not orbital debris but from much further out there:

An Interstellar Meteor Struck the Earth in 2014, and now Scientists Want to Search for it at the Bottom of the Ocean - Universe Today

This is a very interesting project that will collect a lot of magnetic material from a 1.7 km deep sea bed. The collection may include desired object. I am not much convinced that anything 'interstellar' can be learned after 8 years in seawater.

I do not argue against trying. They will also collect degraded solar system meteors unavoidably, and things could be learned from analyzing them. I see it as a glittery project with possibility of collateral benefits.

 

Another down goer

Retired NASA satellite expected to fall to Earth on Sunday

https://aerospace.org/reentries/erbs-id-15354

Launched 1984 before controlling such trash was considered a thing, and <3 tons so not attaining the level of interest in 22 tons of more recent thoughtless re entries from a large Asian country you have heard about.

But down ERBS will go, and most likely as always into its final ocean home.

 

ERBS splashed in Bering Sea.