Juno extended mission

Juno at Jupiter: Extended Mission Flybys of Galilean Moons
by PAUL GILSTER on JANUARY 11, 2021, Centauri Dreams

The proposed Juno extended mission (EM) would take advantage of the natural northward progression of the periapsis of the spacecraft’s orbit and the consequent lowering of spacecraft altitudes over Jupiter’s high northern latitudes. The EM would run until the end of the mission, with an expected duration of approximately four years. Under the High and Medium Scenarios, propulsive maneuvers would be utilized not only to target Jupiter-crossing longitude and perijove altitude, as during the prime mission, but also to target close flybys of Ganymede, Europa, and Io. The flyby maneuvers would act to shorten the spacecraft orbital period, yielding more close passes of Jupiter within a given time interval, and increase the rate of northward movement of spacecraft perijove. Under the Low scenario for EM operation, the satellite gravity assists and close satellite flybys would not be attempted.

from the Senior Review

Exciting new data from Jupiter inbound over the next 5 years. Just in time for this….

SpaceX starship at Jupiter (early concept)

Point to point sub orbital

Preparing for “Earth to Earth” space travel and a competition with supersonic airliners From NASASpaceFlight.Com an important and fun source on space activity all around the world not just NASA/US

So this seems crazy but in all honesty it has actually been a thing for a long time. It is mentioned in a lot of sixties/seventies SF not focused on space flight. It was seriously studied several times as a sort of replacement for parachute insertion of military force. And like most of those sorts of efforts there was a commercial concept to support the technology since the folks in the defense industry understood that military programs cannot support a robust industry on its own.

Just look at nuclear power, there was a reason that nuclear power stations evolved as the Navy came to realize they wanted nuclear ships. And there is a reason that small aircraft carriers and non nuclear submarines are anathema to certain parts of the Naval establishment. They know that if non nuclear CVs and SSs became common the industry required to support the nuclear fleet would become unaffordable.

https://thehighfrontier.blog/2016/03/20/straight-back-down-to-earth-a-history-of-the-vertical-takeoffvertical-landing-rocket-part-1/

People have already talked about the DoD buying Starships and using them as bombers / hypersonic weapons platforms. This is just turning the model above around.

Back in medieval times freighters and warships were the same thing, they just tacked on some fighting platforms and went at it with bows, crossbows, catapults, swords, etc. Even the Vikings probably started out as traders though always ready to ‘raise the black flag and slit a few throats’ if that looked like the right business strategy.

Anyway…sorry for the side commentary, it’s evening and I had a good dinner so I’m wandering a bit.

So, again anyway…if you look at it, a craft like the Starship, which has the performance as a single stage vehicle to haul 100 tons 10,000 miles in less than an hour has some attraction on its face….but in reality?

  • To my mind the most value dense time sensitive cargo is people but that’s years out at the least.
  • In the meantime are there cargos that are so time sensitive that something like a starship might make sense?
    • Couriered documents. Maybe
    • Mail. Does not seem like it.
    • Medical supplies only if the ship could land almost anywhere and take off again.
    • High value tech like chips? Maybe but 100 tons is overkill.
    • In fact most of the above are not 100 ton class cargos and frequency and flexibility of landing seem critical.

So dead on arrival? No there are customers who might pay for a a limited 100 ton capability. I think it would need to be anywhere in the world which is more than 10,000 miles but is probably within the capability of a modified Starship with more fuel and less cargo…or maybe an extended tank Starship could do 100 tons out to 18,000 miles (my wag of anywhere in the world from anywhere in the world.)

A somewhat smaller starship could do 10 tons 18,000 miles and probably land at just about any port or airfield as long as you can supply LOx and LNG, which is not that uncommon.

Go back to the start. If you burn a couple of hundred tons of LOx/LNG what is the cost? Does it make economic sense? Is it safe, is it going to be acceptable?

  • Economics:
    • LOx/LNG are in the same $/ton range as Jet fuel, you are burning a couple of times the fuel since you have to haul up the oxidizer with you and pay for that as well so say 4x the fuel bill.
    • The hull is in line with a modern airline.
    • If you can do a trip a day or so with support costs in the same range as a jet, it would appear to me that for the right cargo you could make it work.
  • Is it safe?
    • Well not right now but once the tech is wrung out ?? I think so.
    • the big difference is much higher energies than a jet.
    • But…your exposure time is a fraction of that of a jet over the same range. Accidents in mid flight are rare but generally lead to complete loss. Exposure time is probably the most important difference…advantage Point to Point
    • Ok so the major threat time is when you are near the ground around take off and landing, Those are shorter for the Point to Pointer.
    • And to me the difference in energy involved is immaterial…dead is dead and most of the time accidents of any magnitude in those phases are not survivable.
    • Accidents on the runway often have survivors but that is eliminated in the Point to Point case…up and down…no in between…
  • Acceptable?
    • Only time will tell, my guess is YES.
    • It will be a bit like the glamor days of the early airliners I would expect point to point for certain segments to be a real elite punch card
    • Especially as near earth space becomes an exotic but achievable location.

Exciting times indeed.

SpaceX and COVID 19 Relief

Sunrise at Boca Chica, SN9 on Launch Mount B being readied for the test campaign. Thanks to Mary and all the gang for keeping me sane.

So one of the things that has kept me a little bit sane this last 9 months is SpaceX, Starship, and 24 Falcon launches… All I have to say is WOW and thank you Elon!

I’m in the periphery of the electric car business and have been for over twenty years now. The only thing that made me a believer was Tesla.

I’ve been watching space since I sat in front of the telly as Armstrong stepped off the lunar lander. The first time I believed that the final frontier finally within grasp was watching SpaceX doggedly pursuing landing Falcon boosters.

I’ve been a big believer in sub surface transportation, in particular for cargo and rapid medium distance, since high school! And the first time I saw it really taken seriously was Elon’s Boring Company.

It is really hard to think of another great innovator who had such a broad impact in the world. Brunel maybe (Victorian England) Edison, Tesla, Marconi, the Wrights, Sikorsky, Johnson…they all did great things only Brunel had as broad as Elon Musk. Maybe some of the other engineer entrepreneurs of the 1850’s to 1950’s working in what would become industrial powerhouses might have been similar but a different time and public culture hid them…maybe it’s just that Elon’s working today and as a geek I gravitate to him and the search engines feed my observer bias.

10 story Grasshopper does a little daring

Slashgear.com : SpaceX Rasshopper aces side tracking reusable rocket test go check out the video at the link way cool as always!20130814-190927.jpgEven more exciting, there’s some more details on the next steps!

Of course, the system will have to go significantly higher if it’s to be of use to NASA. SpaceX plans to introduce a second version of Grasshopper – known as v1.1 – sometime after October 2013, which will stand 160 feet tall and use nine of the engines from the Falcon 9-R rocket, rather than Grasshopper v.1′s single engine.

When testing begins, Grasshopper v1.1 is expected to eventually fly to heights of 300,000 feet, launching from a specially constructed pad at Spaceport America, New Mexico.

SpaceYES!!

SpaceX continues to drive down the barriers like the aggressive but rationale organization they are and the world needs to move us to the next level of Earth to orbit operations. And having a dream and stretch goals are required elements.

From NASA Spaceflight: Dragon Roadmap: From domestic crew independence to humans on Mars
July 5, 2013 by Chris Bergin
20130706-222213.jpg20130706-222206.jpgGrasshopper reaches a thousand feet in new nav test. Read more at: SpaceX shows off new nav gear with latest Grasshopper rocket launch-and-landing (video)
By Timothy J. Seppala posted Jul 6th, 2013 at 3:47 PM
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Merlin 1D engine ready for space

The SpaceX Merlin 1D engine, the more powerful, more robust and less expensive
follow on to the operational 1C, has been certified for flight.

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This is the family, an interesting thing about the Heavy is the plan to have the strap-ons share fuel with the core, consequently when they separate the core is still fully fueled, a big performance increase.

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The engines have been run far harder than standard rating regimes require, 1) to solidify their ‘man rating’ for future crew lofting flights, 2) because SpaceX wants to reuse them, 3) because SpaceX wants top line insurance rates for their customers even while brining new approaches to the party.

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Rocket engines, so ugly you just know they’re powerful!

SpaceX Grasshopper, hops up 820ft

Cool videos at the Verge article.

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Held at height and then landed straight down unaffected by what looks like a reasonable breeze.

Second gen Falcon this year, possibly Falcon Heavy first flight, soft water return for a booster this year and ground return next year! Each demonstrates fundamental capabilities and the power of a committed commercial / civilian play with tech and team unfettered by bull crap FARS oversight dead weight. But each is advancing tech at a rate that seems more reminiscent of the sixties NASA and aviation tech| 2nd gen Falcon: new improved engines, Heavy: buddy tank w/ common boosters engines, any of the above: fly back boosters w/ powered soft landing first at sea then on land. Each step something daring and commercially valuable. I’m not sure how some of the competitors keep from going into terminal depression, if Musk’s SpaceX team nails the string the old guard are toast.