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Japan Launches the World's Smallest Satellite-Carrying Rocket (nasaspaceflight.com)
Japan has launched the world's smallest satellite-carrying rocket. Long-time Slashdot reader hey! writes:
Last week Japan Aerospace Exploration Agency (JAXA) successfully placed a three-kilogram cubesat into an 180 x 1,500 kilometer orbit at 31 degrees inclination to the equator. The payload was launched on a modified sounding rocket, called the SS-520-5. The assembled rocket weighed a mere 2600 kilograms [2.87 tons] on the launchpad, making the SS-520-5 the smallest vehicle ever to put an object into orbit.
Note that the difference in the SS-520's modest orbital capacity of four kilograms and its ability to launch 140 kilograms to 1000 kilometers on a suborbital flight. That shows how much more difficult it is to put an object into orbit than it is to merely send it into space.
Note that the difference in the SS-520's modest orbital capacity of four kilograms and its ability to launch 140 kilograms to 1000 kilometers on a suborbital flight. That shows how much more difficult it is to put an object into orbit than it is to merely send it into space.
... miniaturization.
It little behooves the best of us to comment on the rest of us.
Yeah, buy 140 kg is a suborbital lob, and that's not nearly as insanely small. The Davy Crockett has a mass of around 40 kg https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device). That involved pretty heavy miniaturization, but a warhead with slightly higher yield and slightly less miniaturization and a size of around 140 kg isn't implausible. Detonating a nuke the size of Davy Crockett on New York still does some pretty serious damage http://nuclearsecrecy.com/nukemap/?&kt=0.04&lat=40.72422&lng=-73.9961&airburst=0&hob_ft=0&zm=16 and if one increases the size even a little bit, the damage starts looking pretty extreme. And the US was able to build the DC in the 1950s, so some components even North Korea would be able to automatically get smaller (such as the electronics). And DC was a variable yield weapon, so if one takes out the extra stuff for that, one also gets a little bit more. That said, it does look like as of right now, the smallest nukes that North Korea has are still much too big to fit on this sort of rocket.
Scott Manley is a great youtube commentator on space stuff. Last year he made a video on the smallest orbital rockets.
Since then, Electron and now SS-520 have orbited satellites, so it is a little out of date. He starts with the Electron and talks about the previous SS-520 launch is covered at 4m40s. Numerous other rockets get a mention.
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They've used that for anti-satellite missile tests that were successful before. I'm sure that one or other of the "black ops" outfits has some such capability to quickly put spy sats in orbit.
Why not to design the satellite as some sort of long cilindre and to use a militar converted jet to carry it "near" the atmosphere limit
You've just re-invented the Pegasus. Not to mention Virgin Orbital. And Stratolaunch.
You do need something that carries a heavier payload than a fighter, though--
and just to send it the remaining distance as a missile?
It's not the distance-- it's the velocity. Orbital velocity is about Mach 25; you only get a tiny fraction of that from a jet. But, it does help, some, mostly because getting above much of the atmosphere does help.
http://www.geoffreylandis.com
Probably because it wouldn't make that much difference. Getting to space is the easy part; the lion's share of the energy needed for low earth orbit is accelerating your payload to 7km/s or 15,000 mph.
Using a mothership makes a lot of sense if you're going for a suborbital jaunt, as with SpaceShipOne, which at 3600 kg is comparable in size to this rocket. But the energy savings you'd get is such a tiny fraction of what's needed for orbit it's not worth the engineering and logistical complications.
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I imagine you could land a payload anywhere on earth if you send it up 1000km, like this rocket can do with 140kg payload.
No, not even close as rockets have no air to glide in or wings to glide with. When NK sent their Hwasong-15 missile about 4500km straight up the experts said it could hit a target about 13000km away on a ballistic trajectory. So for a 140kg payload I'd estimate a 3000km range. And this is a considerably more powerful rocket than what NK got, it couldn't put anything in orbit and their test launch probably had essentially no payload. North Korea could almost certainly nuke Japan if they wanted, that's only 1000km away and presumably reachable with a 100+ kg payload. The US? Probably not so much, the rocket could get there but it'd have to be a very light payload. Maybe a kilo of mutated ebola or whatever, if they have that.
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Because 140kg is a nice size for a small nuclear weapon. And 1000km is a nice range for hitting Korea and....
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The SS-520 was first launched in 1998. It is based on the S-520 which was first launched in 1980 (source).
Yes, the SS-520 and S-520 could be used as weapons, but that has been the case for decades. Nothing in this test makes them more weaponizable than they were before the test. There is no reason to think this test had any ulterior military motives.
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JAXA has vehicles capable of putting over sixteen metric tons in orbit.
But if they wanted to nuke North Korea, the easiest way would be to adapt a missile fired from one of their attack submarines or guided missile destroyers.
Really, JAXA has done something cool here, and the only context people can think of it in is nukes?
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