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JAXA (& other Japanese) Launch and Discussion Thread


tater

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11 hours ago, JoeSchmuckatelli said:

I know this is a side issue - and one affecting other advanced economies like SK, etc., but I wonder if it will be as problematic as predicted.  Certainly the world has never experienced a net reduction in population (as some predict peak human population @ 2080). But I wonder if this fear is based on the 'traditional way of doing things'.

Given that necessity is the mother of invention, a country like Japan is highly likely to figure out a solution.  One that may rely on good relationships with other countries - something Japan enjoys. 

Having said that - I agree that so long as purchasing seats is viable for human launch, that makes economic sense - I still would hate to see a nation with the technical and manufacturing skill of Japan get out of space entirely.  

It’s not so much the declining population alone, it’s the combination of young people heading to the cities and depopulation of the countryside- and thus loss of the agricultural workforce- that is a huge red flag.

This happened to the USSR starting in the 1960s, and is the reason why they had to keep importing more and more food and eventually had the disastrous shortages of the 80s.

Japan’s food self-sufficiency is already low, and loss of domestic production would be a major problem, to say the least.

I don’t think “Japan” should abandon space, I just don’t think it should be the government paying for it. I also think Japan would highly benefit from a focus on robotic exploration. iSpace, the company that attempted to land the Hakuto-R lander (launched by Falcon 9) is where the future of Japan’s presence in space after the ISS lies. I could see them building a laboratory module for the future Artemis lunar base. Of course, Toyota will be building the big pressurized rover for Artemis.

I think the country’s strengths lie in habitats (orbital or surface) and robotic exploration. So long as Japanese society continues to head the direction it does, it makes more sense to do those instead of duplicating Crew Dragon.

6 hours ago, Exoscientist said:

 By “next” manned launcher,  I mean the next space agency in the world to achieve manned spaceflight after the Russians, Americans, and Chinese.

 By the way, I looked up the Apollo Command capsule and found that the capsule itself without the service module only weighed 5,800 kg. The Apollo service module provided the propulsion for entering and exiting from lunar orbit and wouldn’t be needed for missions just to LEO:

COMMAND MODULE 
Crew size: 3 
Length: 3.5 m 
Maximum diameter: 3.9 m 
Habitable volume: 6.17 m3 
Total mass: about 5,806 kg 
(structure 1,567 kg; heat shield 848 kg; reaction control system 400 kg; recovery equipment 245 kg; navigation equipment 505 kg; telemetry equipment 200 kg; electrical equipment 700 kg; communications systems 100 kg; crew seats & provisions 550 kg; crew mass 216 kg; misc contingency 200 kg; environmental control system 200 kg; propellant 75 kg) 
Reaction control system 
    thrusters: 12 x 410 N 
    propellant: NTO/MMH 
    specific impulse: 290 s 
    total impulse: 257 kNs 
L/D hypersonic: 0.3 
Power: Ag-Zn batteries; 3 × 40 Ah each, 28 V DC; 3.4 kWh; inverters produced 115 V AC 
Environment: pure oxygen at 340 mbar 
http://www.braeunig.us/space/specs/apollo.htm

 Also, surprising is how little mass is required for the environmental control system, at only 200 kg out of the 5,800 kg.

   Bob Clark

Continuing from my last paragraph in reply to Joe, I would say that even if Japan had a semi-reusable capsule like Crew Dragon, it would not be competitive because of the expendable launcher. A triple core H3 would also cost way to much money to launch on a regular basis.

Japan’s efforts are much better spent building space station and lunar base modules, and large pressurized rovers.

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The European rover for the MMX mission to Phobos has arrived in Japan.

I wonder what it was like filling out the customs paperwork, hehe.

MMX (Martian Moons eXploration) will launch in 2026 on an H3 rocket, and aim to return a sample to Earth from Phobos in 2031. The spacecraft will also conduct flyby observations of Deimos.

Surprisingly, a Phobos sample return has actually been attempted in the past. Fobos-Grunt infamously became stranded in Earth orbit in 2011, falling back to Earth and taking China's first Mars orbit attempt with it.

I think this mission is pretty cool. I think that's what ESA and JAXA should strive for, trying to perform niche missions that don't get attention from the holders of the purse in the US, who might be more interested in flashy Mars and Jupiter missions. JAXA and ESA have already gone to Venus and Mercury, respectively, whereas NASA has not, and should continue to do so, allowing NASA to focus more on preparations for a crewed Mars expedition and Outer Planet exploration.

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1 hour ago, SunlitZelkova said:

JAXA and ESA have already gone to Venus and Mercury, respectively, whereas NASA has not

?

Mariner 2 and Magellan went to Venus and Mariner 10 and Messenger went to Mercury.  But the former USSR holds the Venus trophy for sure, 

Edit:  Also Pioneer Venus.

Edited by darthgently
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4 hours ago, darthgently said:

?

Mariner 2 and Magellan went to Venus and Mariner 10 and Messenger went to Mercury.  But the former USSR holds the Venus trophy for sure, 

Edit:  Also Pioneer Venus.

Yeah but that was like decades ago. BepiColombo and Akatsuki are now.

Just checked, it's a year shy of a decade since MESSENGER ended. Venus still hasn't been visited for decades (emphasis on the plural).

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3 hours ago, SunlitZelkova said:

Yeah but that was like decades ago. BepiColombo and Akatsuki are now.

Just checked, it's a year shy of a decade since MESSENGER ended. Venus still hasn't been visited for decades (emphasis on the plural).

Magellan radar mapped nearly all of Venus' surface and Messenger imaged all of Mercury's surface, found water ice at the poles and such.  The statement that "NASA hasn't..." seems odd. 

By the "decades ago" logic, humans haven't landed on the Moon several times.  We humans can definitely do better than we are doing now.  Not just at lunar landings, but also at recognizing the shoulders we stand, or at minimum, lean very heavily, upon. 

Maybe I'm a bit sensitive to apparent revisionism in general lately as our cultural fact-based memory is threatened to be replaced with things like Google's AI woeful take on history

Edited by darthgently
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11 hours ago, darthgently said:

Magellan radar mapped nearly all of Venus' surface and Messenger imaged all of Mercury's surface, found water ice at the poles and such.  The statement that "NASA hasn't..." seems odd. 

By the "decades ago" logic, humans haven't landed on the Moon several times.  We humans can definitely do better than we are doing now.  Not just at lunar landings, but also at recognizing the shoulders we stand, or at minimum, lean very heavily, upon. 

Maybe I'm a bit sensitive to apparent revisionism in general lately as our cultural fact-based memory is threatened to be replaced with things like Google's AI woeful take on history

Fair point.

I retract that statement about NASA not having gone. But they aren't there right now, while JAXA and ESA are, and therefore NASA should focus on Mars and Outer Planet exploration.

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  • 2 weeks later...
3 minutes ago, tater said:

Unsure when T=0 is..

Looks unofficial, maybe direct from the news outfit.  Did I see an inflated blimp fin nearby when the camera panned far right?  May be streaming from a blimp.  That has to save the them money over a helo

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Just now, darthgently said:

Looks unofficial, maybe direct from the news outfit.  Did I see an inflated blimp fin nearby when the camera panned far right?  May be streaming from a blimp.  That has to save the them money over a helo

yes, apparently the official coverage dropped, the only one live was a news feed.

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Google Translate says the livestream's title says "Launch scheduled for 11:17 AM, no launch Private launch ticket "Kairo" launch schedule changed"

So apparently it's a scrub?

Translating a few comments in the live chat, some said that the winds above are getting a little high than wanted.

Also people walking around on the pad, so probably a scrub.

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https://news.biglobe.ne.jp/smart/amp/domestic/0309/ym_240309_6002487817.html

A little about it. It’s from a Tokyo based company called Space One. Its planned payload was a “small government satellite.”

The launch site is called Spaceport Kii, located in Wakayama Prefecture. This is interesting as it’s only an hour’s ferry ride from where my grandma lives.

Space One’s website- https://www.space-one.co.jp/

Payload capacity of the vehicle is 150kg to 500x500 SSO @97 degrees, or 250kg to LEO at 500 km altitude @ 33 degrees.

Company mission is the basic spiel. Lower cost access to space and get space economy going.

They want to launch about 20 times a year during the rest of this decade, and the first launch was originally scheduled for summer 2023.

The vehicle is a solid fuel launcher. The route they’re going to lower costs is using cheap materials instead of reusability.

They aim to have a very short time to launch after signing the contract, about one year to be exact and launching within 7 days after taking delivery of each satellite for integration.

This makes me curious what the lead time on a Rocketlab or SpaceX launch usually is.

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I'm reminded of what happens when poorly poured solid fuel has big hidden voids, or develops long vertical cracks as it cures, causing the burn rate to go up dramatically, explosively even, with suddenly increased exposed surface area as those voids are opened during burn.  Not saying this happened, just reminds me of that.

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1 hour ago, darthgently said:

I'm reminded of what happens when poorly poured solid fuel has big hidden voids, or develops long vertical cracks as it cures, causing the burn rate to go up dramatically, explosively even, with suddenly increased exposed surface area as those voids are opened during burn.  Not saying this happened, just reminds me of that.

I’m pretty sure those types of defects are found with xray or ultrasound testing 

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