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Thanks again for your work!

I'm hoping that next year I can get down there to try and watch a launch again.

This is an exciting week. Monday night there is an other Falcon Heavy launch from the cape. It’s the hardest launch they’ve other done due to dropping intolerance payloads into multiple orbits for the Air Force. It also includes lightsail 2.0 from the planetary society.
Thursday morning is an atlas launch for you ULA from the cape. It’s the 551 which is the largest Atlas around. Should make for a very exciting visuals and audio.
Also Thursday early morning is another Electron launch from New Zealand. They are very exciting to see. They use electric (hence the name) pumps instead of having a pre-combustion that burned liquid rocket fuel like most launch providers due. It keeps simplicity at the expensive of battery weight.

If starlink works out, i'm a prime candidate i think. Cell phone internet has gotten pretty passable though.

That launch was amazing. I ended up going home after the 3 hour delay since I didn't think the kids and wife would take well to staying out that late. In hindsight I should have driven back over after dropping them off. Oh well. It's a little bit of a shame that the center core didn't make it. Elon confirmed yesterday that they engines were burning so hot it burned through and broke the gimbaling mechanism on the center engine. Apparently the rocket noticed that and did an 'abort' to bring the whole rocket safely into the water instead of crash-landing on the deck. I haven't heard if there was any damage to OCISLY. Obviously the most important part was the payloads and those all went off without a hitch.

A UFO crash-landed in a backyard in Michigan on Saturday morning:
https://hothardware.com/news/samsung-spaceselfie-crash

If a satellite every lands in my backyard I want it to be named something other than "SpaceSelfie".

Pretty sure it didn’t cross the Karman line and thus not “space”.

Usacomp2k3 wrote:

Pretty sure it didn’t cross the Karman line and thus not “space”.

Yea i was thinking this was more like a high altitude weather balloon than a satellite.

Cutting-edge scientific data from a spacecraft launched more than 40 years ago:
https://www.nationalgeographic.com/scie ... 2-reveals/

JustAnEngineer wrote:

Cutting-edge scientific data from a spacecraft launched more than 40 years ago:
https://www.nationalgeographic.com/scie ... 2-reveals/

RTGs are about to expire though and while we are pushing limits of what DSN can handle.

Krogoth wrote:

RTGs are about to expire though and while we are pushing limits of what DSN can handle.

The RTGs aren't about to expire. Their output, since day 1, has been slowly diminishing (it's called half-life kids, it's not just a game!). This, going back nearly 30 years now, has required turning off more and more functionality and instruments. It's therefore nothing new.

At some point, in the middle of the next decade or so, there won't be enough output left to power any individual instrument.

That is the problem, not the transmission or its reception.

Glorious wrote:

Krogoth wrote:

RTGs are about to expire though and while we are pushing limits of what DSN can handle.

The RTGs aren't about to expire. Their output, since day 1, has been slowly diminishing (it's called half-life kids, it's not just a game!). This, going back nearly 30 years now, has required turning off more and more functionality and instruments. It's therefore nothing new.

At some point, in the middle of the next decade or so, there won't be enough output left to power any individual instrument.

That is the problem, not the transmission or its reception.

A few years of practical use for something that was designed a lifespan of several decades fits within the definition of "about to expire". Transmitter is slowly losing power and it is a question if DSN still can receive from it before it completely shuts down.

Krogoth wrote:

A few years of practical use for something that was designed a lifespan of several decades fits within the definition of "about to expire".

If your purpose is to mislead rather than inform, sure.

But why would you do that?

Krogoth wrote:

Transmitter is slowly losing power and it is a question if DSN still can receive from it before it completely shuts down.

Let's ballpark this: The RTG (plus degrading TCs) is ~50% of what it was after ~50 years.

This is therefore not the problem.

Why, you might ask?

Allow me to explain: Take a calculator, and then divide one by something that is squared.

Even a smaller number, such as two, gets into why this is problem (and it is known as the inverse-square law)

1/(2^2) = .25

As you can see, we're already at 25%!

----

As to reception/transmission: We don't run in practical problems that intercede into the theoretical for decades unto hundreds of years, rather, it starts to be a bit a second, a bit a minute, a bit an hour, etc.... (as it was originally hundreds of thousands, now ~hundred a second...)



EDIT: Rethought snark and removed it (mostly!)

Oops...
https://hothardware.com/news/spacex-starship-explosion

Perhaps they should go with a pressure tank company instead of a water tank company...

In slightly less explosive news :

https://phys.org/news/2019-11-space-gut-leaky.html

Guess artificial gravity is now a requirement for space travel...

The way forward was demonstrated back in 1968 in 2001.

Actually, Wernher von Braun proposed it more than a decade before in 1955 while explaining what the first manned moon mission might look like.

There goes the neighborhood.
https://abcnews.go.com/Technology/massi ... d=67385911

JustAnEngineer wrote:

There goes the neighborhood.
https://abcnews.go.com/Technology/massi ... d=67385911

That's why it's such a long distance between a theory and a law.

There's some question about the distance from Earth, also. The estimate from the Gaia spacecraft doesn't agree with the estimate cited in this study, but as the authors noted that figure may not be accurate if there is in fact a black hole in the mix here.

https://www.sciencenews.org/article/new ... rdly-heavy

It seems there may also be some great health benefits to microgravity :

https://www.universetoday.com/144207/cancer-seems-to-have-trouble-spreading-in-microgravity-1/

I'm don't have much faith in that devices ability to reproduce "microgravity" within a centrifuge. I'd like a closer look at it.

Not to mention that going to space is an odd choice for a cancer treatment because of the increased radiation exposure. I guess if you've already got cancer, then you don't need to worry about that.

Redocbew wrote:

Not to mention that going to space is an odd choice for a cancer treatment because of the increased radiation exposure. I guess if you've already got cancer, then you don't need to worry about that.

If they stay in space and get any additional tumors due to the increased radiation, those will grow slowly due to the microgravity but if they return to land, they might be looking at some pretty aggressive "pissed off" tumors. So I guess they just need to stay in space forever.

Dark humor aside, the point was that you can't really get away from the Earth's gravity while still on Earth. Being stuck in a centrifuge is not the same as being in freefall. It doesn't compare to gravity in the same way. I'm sure the researchers know that, and they're just doing the best they can to approximate an environment of microgravity using the resources at their disposal. And of course we could be looking at correlation here rather than causation.

There's been research on the effects of microgravity on molecular and cellular biology for many years now, so it's not really a new idea.

Highest resolution image of the Sun's surface so far: https://phys.org/news/2020-01-nsf-solar ... s-sun.html

https://www.youtube.com/watch?v=znBesUwVOok

NASA's worm logo will return to space.
https://www.nasa.gov/feature/the-worm-is-back

So much Space stuff has happened

Crewed mission to ISS and safe splashdown. 9 years since last space shuttle mission and 40ish years since splashdown

three Mars missions are on there way mars, including Perseverance Rover.

SpaceX “hopped” a grain silo sized piece of stainless steel 150m in the air with 1 raptor engine at 50 ish percent power

SpaceX also recently pushed a Raptor engine up to a record 330 bar combustion chamber pressure on the test stand.