Shoot for the sun!

[KnightWhoSaisNi]

Concluding, btw, that the sun seams to be a single-point gravity source rather than a real celestial body.

[CarolRawley]

[snip]

CarolRawley (missing, presumed lost, on account of having no engines)

[/snip]

Hadn\'t looked at the MIA roster for a while... Yay!

I have an announcement to make....

This one managed to get into a low Solar Orbit.

It had a Pe of about 12,250m

[screenshot missing. Blame space dragons.]

Back into Intercept Orbit for return journey.

Waited for about 700 days for the Intercept orbit to sync with Kerbin.

Nothing happened.

Just after the time log started displaying randomly, the craft crashed into the Mun. The impact was enough to deorbit it.

...

...

Ah, well. Better luck next time, I suppose.

[Ydoow]

LOL

You deserve a medal for deorbiting the Mun

[boolybooly]

Well both KnightWhoSaisNi and Ignite A Light deserve a mention in the roll call of honourable failures. It has become a lot harder with the new orbital dynamics. Getting that close to Kerbol Ni is a feat in itself and deorbiting the moon Ignite is, well... awesome!

I have not tried exploring outside Kerbin - Mun since early v12 because there was a jinx on the spaceship, some kind of bug where the center of gravity was off when it went into solar orbit but I have built a new ship for v13 and will try again another day.

I will have to think up new conditions for the skill titles to suit the new physics.

[Guest ThatCrazyPilot]

I WIN

[Guest Flixxbeatz]

minutes later...

[boolybooly]

Thanks for the screeny which confused me there for a moment Wernher Von Braun aka Buzz Aldrin fka ThatCrazyPilot, not hard to do, but because you are going so fast away from Kerbin there is little doubt your ship got lost in space. Duely noted. Let us know if you make it back to base.

Flixxbeatz, that is an interesting looking station/ship and a good spot for some rays. Logged. I am guessing you didnt get home?

Also special mention for sneakeypete who also goes on the v12+ lost in space roll, not sure why I missed him before, maybe I was ninja\'d.

btw, I have now modified the OP, which was all out of date. The new challenge is to ...

Make one full orbit of the sun Kerbol, outside Kerbin+Mun, with a PE of half the altitude of Kerbin or less, then land on Kerbin. Aim for the launch pad as best you can.

OK to check this is even possible I have done the mission with a stock parts ship. Ran into a bit of a terrain bug on my return to Kerbin though and had a big problem controlling the craft in deep space, seems to be some kind of bug affecting attitude control for multistack ships outside Kerbin + Mun orbit, but wow, what a ride!

[zarakon]

Yesterday, someone posted a ship in a challenge thread that was able to reach ~9600m/s straight up from Kerbin with stock parts (here). I realized that was perfect for decaying my orbit around the sun to fall right in.

I hadn\'t read anything yet about what happens at the sun, so this was all new to me..

In the attached images 1-11:

1. Orbital velocity eliminated. Starting to fall toward the sun.

2. Getting close to the sun, speed at 30km/s

3. Map view showing straight-line trajectory. It doesn\'t display perihelion..

4. Only 64km altitude! 188km/s

5. Strange, altitude is going back up, but so is my speed. 200km/s

6. Map view reveals that the altitude reading has gone negative, and I\'ve still got a ways to go.

7. 59Mm into the sun, speed is up to 627km/s. G Force meter is maxed out

8. Never quite reached 60Mm, that must be the radius of the sun. When I approached the very center, the physics simulation broke down and I got flung out at 54,462km/s!

9. The forces in that slingshot apparently broke my ship in half, and the two pieces are slowly separating.

10. My craft was sent out of the system, almost straight down from the plane. I only lost a few hundred m/s of velocity while escaping the sun.

Not pictured because a screenshot wouldn\'t show anything, but the navball was flickering back and forth between two different headings, and trying to view the solar system in map view started to produce similar glitchy behavior.

11. I let it run at 10000x speed for about an hour, and approached the 999999Gm mark. At 999000 I started slowing down speed so that I could get a screenshot at 999999, but when it reached about 9991500, everything broke, as you can see in the screenshot.

It was a fun trip!

[Raxael]

Funny story about this ship. It was intended to drop off a satellite into orbit, but as i was increasing my orbit, my insane solar skills kicked in and brought me into orbit with the sun. I didn\'t get close enough to complete the challenge, but I thought it was worth posting my trusty ship of discovery, as well as its orbit.

Now that I realize it, I probably could have landed at Kerbin, as I intercept its orbit twice. It would take many orbits, though...

This ship took alot of tries to make. It relies on spinning to stay stable, but if it spun to fast, it broke apart and asploded, so I take great pride in this. Its not even completed, those are just the first two stages. Next step: ramming into the sun.

Btw, I used the Spheara mod.

[Luigibro606]

Welcome to the forums!

Currently we can\'t crash into the sun as it\'s just a light source, but soon it will become a full celestial body.

[boolybooly]

hi zarakon and Raxael, thanks for describing your adventures with some interesting screenies, I have recorded your flights on the roll call of intrepid pilots who got lost in space while shooting for the sun.

Better luck next time, let us know how it goes.

Solar orbit is a whole different barrel of monkeys to Kerbin orbit and making the intercept to return for landing while doable is especially tricky with the deep space attitude control bug still operating. However the smaller the ship the less of a nuisance it is so if you had the fuel Raxael, you could get back to kerbin from that position by decreasing the apoapsis slightly so that you catch up on the faster periapsis part and dont slow down as much on the apoapsis. Then when flying parallel you can adjust orbit so you intercept Kerbin. Not sure if that will help any, just thought I would mention it

btw zarakon that was one heck of a slingshot by the sound of it, congratulations on breaking Kerbol !

[boolybooly]

Using v13.1 due to the stage bug in v13.2, I built a 67 tank (6x5 + 6x5 + 1x7) stock ship for the mission (screen d) given what we know about the Kraken I figured a long single stack orbiter would be best. I figured RCS would be unecessary as I had a gimballed stock t45 engine in case it got really bad and anyway it shouldnt as the ship was a simple design... in theory. So I did my major escape and deceleration burns inside Munar orbit with a radial multistack and then ditched the outside stacks leaving me with the 7 tank orbiter.

This got me below half the altitude of Kerbin as per the mission and then back up to Kerbin a little ahead. The Kraken attacked and nearly borked the mission but I managed to use the old switch-to-5x-and-back ploy to stop the ship tumbling at a useful attitude. I made a wide orbit within the 82,000,000 meter range of Kerbin SOI ie within 13,616 Mm (ie Kerbin altitude 13,534Mm + 82Mm) and waited for it to catch up which it did. I made some aerobraking passes, noticed a bug with stepwise changes in AP and PE markers when not on rails and got lucky with my final pass as the KSC terrain was on the right side of the planet for me to target so I made a shot for it and hit the mark with a landing on KSC terrain which at this point was the only flat bit of land on Kerbin. I hit it quite fast at 13.6 but got lucky again and didnt blow up.

FIN

[deadshot462]

'You maniacs! You blew it up!'

[witeken]

I Win

From 0.0 speed (3min25sec) to 61.000.000 m/s. Perfect Kerbol dive.

[boolybooly]

Your Kerbal\'s sacrifice is not in vain witekin, they will be remembered in the ticker tape parade.

Clocking 1/5th the speed of light, impressive speed! 8)

[nivvydaskrl]

Ooh, this challenge!

I\'ve done some math, and I think I\'m gonna take another stab at it using the new criteria. I\'ll share my math...so, WARNING, math geekiness ahead:

Kerbin\'s orbital period as listed on the wiki is 2,543 days. Using the equation for orbital period, the maximum time for an orbit with its apoapsis at Kerbin orbit (13,599,842,304 meters) and periapsis at 1/2 Kerbin orbit is 1,657.55 hours. ( Period = 2*pi*sqrt(semimajor-axis^3 / gravitational_constant_of_Kerbol) )

Acheiving an orbital period of 1/2 Kerbin\'s is impossible in unpowered flight -- in order for the semi-major axis of the orbital path to be one half that of Kerbin\'s -- the radius of a circle is its semi-major axis -- the periapsis of the orbit would have to be the center of Kerbol. We have evidence that this causes, uh, catastrophic rocket failure.

So. We want to minimize the number of orbits Kerbin makes before we intercept it. An orbital period of 2/3 would result in a flight where the rocket orbits three times before rendevousing with Kerbin on its second orbit around; however, that leads to an orbit with a period of 1695.33 hours -- slightly too long, which means our periapsis will be slightly too high to qualify for the challenge.

The next best option, then, is three Kerbin orbits. After some number twiddling, an orbital period of 3/5ths of Kerbin\'s fulfills our requirements nicely: our periapsis comes out to 5,656,838,754 meters, and our mission time should 'only' be 317.88 days -- about 46 real life minutes at 10,000x time compression.

Sooooo, my intended mission profile is currently: boost to Kerbin orbit, adjust orbit such that its apoapsis is slightly outside of Kerbin\'s sphere of influence (or such that we\'re barely at Kerbin\'s escape velocity). Once that\'s acheived, bring periapsis to as close to 5,656,838,754 meters as possible with fine RCS bursts. Wait until we reach periapsis. Adjust orbit such that apoapsis is as close to 13,499,842,304 meters as possible, to correct for the initial escape burn. Wait another 4.5 orbits.

If everything\'s correct and proper and nothing goes terribly awry, we should pop into Kerbin\'s sphere of influence with a relative velocity of around 2,180 m/s, with Kerbin on a direct collision course with us.

If everything isn\'t correct and proper, we do have some leeway. Kerbin moves through a space equal to its own SOI every 151 minutes, and our velocity relative to Kerbin will extend that window somewhat (though I\'m not sure how much).

As soon as I get home from work, I\'m gonna build a rocket and give these numbers and procedures a test run. I didn\'t use an orbital calculator tool -- I have a page full of scribbled numbers -- so I might be WAY off. Even a near-miss will make me happy about my number crunching, though.

EDIT: The premise could be tested at a smaller scale by doing a Mun->Kerbin orbit transfer, then an attempt to re-intercept the Mun in 3 orbits, as per the above plan. Hmm...

[nivvydaskrl]

First-shot success with stock parts. I had a lot of screens uploaded and a whole thing written out, but the attachment sizes were too large.

But, the relevant ones are below:

1) Vehicle on the pad. Not really all that huge, considering.

2) Rocket at periapsis after correction burn. The engines aren\'t touched again until rendevous (9.5 months later. )

3 & 4) Rocket making rendevous

5) Touchdown on the broken landscape!

6) The Kerbals roll into a rock and commit suicide after a few minutes. Heh!

[ash73]

nivvydaskrl - Thanks SO much for posting those numbers, I\'ve been trying for days to rendezvous with Kerbin after a solar orbit, finally I made it! I used a periapsis of about 5,656,800km and had to make some adjustments on final approach as my orbit wasn\'t very precise, but my ship was recaptured and the Kerbals made a safe splashdown. Total mission duration 325 days.

The controls are very mushy in deep space and lining up the ship is like trying to push two magnets together. The slow warp factor makes solar orbits a chore too.

[bitbucket_]

I\'ve been lurking silently for months, but this challenge was what got me to break the silence. An interplanetary voyage was the one thing I hadn\'t tackled to satisfaction, being there are no other planets, so why not give it some practice?

My computer is terrible, falls somewhat below minimum recommended specs, and thanks to integrated graphics, Kerbin has oceans of pea soup instead of water. Oh well.

Anyway, on to the mission! Enter the Kerbal Escapecraft:

On the lauchpad, awaiting a space voyage of destiny. This ship is some dreadful chimera made from parts originating from several modpacks. What better to contend with the Space Kraken?

The one downside to the engines I used on the outer boosters is that they\'re liquid fueled SRB-style \'once you pop, you can\'t stop\' engines, that deliver a LOT of thrust. (Jeb insisted.) I prefer to have a bit more control over my boosters for more practical applications like just going to the Mun.

Out of the atmosphere in 90 seconds.

By the time the outer boosters are out of fuel, the Escapecraft is well in excess of escape velocity.

Kerbin\'s gravity slows the ship down a bit, but in a mere 40 minutes the Kerman brothers are beyond the Mun\'s orbit.

It occurs to me at this point that I should not have left the mission planning to Jeb. His outline was basically, 'Point rocket at Kerbol, blast off at FULL POWER!' No direction, no control, no plan, max throttle. Oh, you silly, silly Kerbal. Well, gotta try, right?

Five hours after launch, the ship leaves the relative safety of the Kerbin/Mun SOI and enters the Kraken\'s lair, interplanetary space. It\'s a 20-day cruise to a 4.22 million km periapsis around Kerbol, complicated by wrestling the Kraken over control of the ship while not in timewarp. I manage to fend off the unseen assault on the craft\'s orientation controls in fits and starts.

45 days out, the Escapecraft has come full circle on its first orbit, but Kerbin has gone around almost half an orbit. Getting out to deep space is easy. Getting home is hard!

The second time around, Kerbin beats us to the rendezvous.

Accelerating does not give us the desired result. All we did was raise periapsis to around 8.4 million km.

Retreating to periapsis and again doing battle with the Kraken, plan B goes into effect; first I recorrect apoapsis to just beyond Kerbin\'s orbit, using up what\'s left in the large lower fuel tank and jettisoning it. With less ship to grapple, and not being so deep into Kerbol\'s gravity well, the Kraken is kept at bay as long as we stay under 10km/s.

More or less matching orbits to Kerbin. But it still doesn\'t close the distance fast enough and the Kermans can\'t hold out forever in deep space.

Kerbin pursues the Escapecraft for a full orbit without closing much distance. Finally, I push the orbit out even further, hoping this will be adequate.

Yet another orbit passes; by now the poor Kermans are probably insane and claustrophobic from being pent up in a 2-meter cockpit for four years. Finally, the ship draws close enough to slip back into Kerbin\'s sphere of influence! It\'s now or never, so I slam on the brakes.

Back into a closed orbit around Kerbin after being lost in space for 418 days.

Another retro-thrust to drop the ship into low orbit. Hang on, guys, we\'re getting you home!

Lining up for the deorbit. Apparently some disaster had befallen Kerbin while they were away; the land and sea were in flux, the terrain marred by ridges and escarpments, adding to Bill and Bob\'s usual reentry discontent.

I used up most of the fuel I had left shifting the inclination to try and come down at the space center. I\'ve never pulled off a landing at the space center; the closest I ever came was touching down a stone\'s throw outside the perimiter fence on a return from the Mun. For me, on most missions, it\'s good enough to just get back to the planet.

In the end, I wasn\'t going to risk their safe return on showboating, and decoupled the capsule after ensuring a re-entry, leaving the engine to its fate. At least I\'m landing on the right continent!

The capsule comes to rest about 8 km southwest of KSC. Eh, could have been worse.

The final rundown. After 421 days in space and a 350 million km journey, the Kermans are home, though it seems to them to be a very different Kerbin than the one they left.

At the mission debriefing, Bill and Bob ask what happened to the planet while they were gone, but KSP psychologists inform them that everything is in fact normal—their long journey has given them SPACE DEMENTIA!

Jeb just took it in stride.

Mission accomplished?

[nivvydaskrl]

nivvydaskrl - Thanks SO much for posting those numbers, I\'ve been trying for days to rendezvous with Kerbin after a solar orbit, finally I made it! I used a periapsis of about 5,656,800km and had to make some adjustments on final approach as my orbit wasn\'t very precise, but my ship was recaptured and the Kerbals made a safe splashdown. Total mission duration 325 days.

The controls are very mushy in deep space and lining up the ship is like trying to push two magnets together. The slow warp factor makes solar orbits a chore too.

Hah! Thanks, glad I could be of help! I noticed no-one\'d done the calculations (or posted them, at least) yet, and one of the other trips was a 700 day affair. I thought maybe cranking the numbers would help, and it looks like it did.

I\'d LIKE to find an arrangement faster than 3 Kerbin orbits, but my gut instinct says that 2 is impossible without shooting through the sun or having another powered burn. By circulizing your orbit at a lower altitude, then doing a transfer which intersects Kerbin\'s path of flight using a calculator utility and a very good eye for angles, you could probably pull it off a lot more quickly...but so far as injecting yourself into an automatic rendevous orbit with minimal adjustments necessary, I think 5:3 is the best bet.

Note that my apoapsis for Kerbin is actually incorrect by about 50 million meters or so, but since the periapsis is calculated based on Kerbin\'s orbital period, it works out anyway, provided you do the adjustment burn at periapsis -- the only difference is that the timing error on the first half orbit causes some deviation from proper rendezvous. Even accounting for that, I was within 6 million meters of Kerbin at rendevous; with the proper numbers and timing and very, very careful RCS usage, I bet you could nail a direct hit on the planet and do completely unpowered return. :3

I\'d be tempted to try again for a higher class award, but I\'m way better at hitting a pinhead from 17 billion meters away in vacuum than I am at hitting a target through atmosphere from 100 thousand meters. I\'m total crap at re-entering appropriately without control surfaces. Maybe a solar spaceplane is in order. I\'d TOTALLY go non-stock the second time around though, my rocket seems to be tired of working correctly after its maiden voyage. XD

[boolybooly]

That\'s great work nivvydaskrl, very interesting analysis of optimum PE. Well done with completing the mission, you are already one of the few but I have honoured your accomplishment by de-italicising your name and changing the link !!1!1! I hope you can contain your excitement! btw IMHO you landed fair and square and must have reached 0m/s at some point for your parachute to have disappeared in the penultimate screeny.

Also something I would like to know an answer to is how to make a rendezvous with Kerbin by increasing the apoapsis so the ship slows down and gives Kerbin a chance to catch up, if you got it right you could probably do it in just over one year. I also agree the idea of lowering apoapsis and then burning a new one to catch Kerbin is another way to do it. That was how I did my last mission in fact, only I mistimed it and got ahead of Kerbin and had to wait for it to catch up.

Bedazzled, congrats in completing the mission, you are now a star pilot dude [sPD] and on the guest list of the ticker tape parade. Screenies are easy to take btw just press F1 and then visit screenshots in the KSP game folder. You can convert to JPG in MS paint simply by resaving if you want to reduce file size and can attach when posting for a direct upload to this BB and no hosting required. FYI

Welcome bitbucket_[SPD] << its official. I like your ship btw, congrats on completing the mission and thanks very much for an entertaining, comprehensive, well illustrated, generally awesome write up. You are duly invited to the ticker tape parade.

[nivvydaskrl]

That\'s great work nivvydaskrl, very interesting analysis of optimum PE. Well done with completing the mission, you are already one of the few but I have honoured your accomplishment by de-italicising your name and changing the link !!1!1! I hope you can contain your excitement! btw IMHO you landed fair and square and must have reached 0m/s at some point for your parachute to have disappeared in the penultimate screeny.

Also something I would like to know an answer to is how to make a rendezvous with Kerbin by increasing the apoapsis so the ship slows down and gives Kerbin a chance to catch up, if you got it right you could probably do it in just over one year. I also agree the idea of lowering apoapsis and then burning a new one to catch Kerbin is another way to do it. That was how I did my last mission in fact, only I mistimed it and got ahead of Kerbin and had to wait for it to catch up.

Heh, thanks!

As for doing a rendevous...I think the best one-year solution would be to do a half-orbit down to your goal PE, then burn to raise your AP such that you swing past Kerbin\'s orbit, dangle outside of it for a while, then rendezvous with Kerbin on the downward plunge. The math for this, however, is a little difficult, since you\'re not actually doing a rendevous at AP, you\'re doing it mid-orbit. The closing velocity will also be much, much higher -- not only are you going faster, but you\'re not travelling in the same direction at Kerbin, which means that much of your extrasolar velocity will be transformed into slamming-your-face-into-Kerbin velocity.

I might doodle around with the math some today.

The other option is the most fuel intensive -- drop to a very near-Kerbol circular orbit, then swing out in a new parabolic. This\'d require only two half-parabolic orbits, plus the partial circular orbit to get the correct angle for the rendevous burn. This is how we I do Mun intercepts now, by the way -- circular to intercept parabolic, very fast. The problem is that all the delta-v required to do these orbit adjustments is almost certainly extreme; at least two times what\'s required to do the easier, but more time-consuming, intercept I did. You\'ll need a calculator utility for this, though, or to crunch the numbers to figure out when you need to burn.

Fuel requirements aren\'t really a huge deal when you\'re working with NovaPunch, of course, but when you\'re doing it stock in the current build, the VAB starts to bog down even on the vehicle I used, and making tweaks becomes absolutely painful. -.-

[ash73]

I thought I\'d take my solar rocket for another spin, and this time I saved some screenshots...

Take off, I\'m using various mods and plenty of rocket-power!

Approaching Kerbin orbit, I\'ve given the crew a science lab with solar panels to make their long journey a bit more comfortable:

Destination Kerbol, boosting the orbit to escape Kerbin\'s gravity:

Retro boost, creating a 5:3 orbit with Kerbol (thanks again nivvydaskrl!), controlling the ship is tricky outside the Kerbin/Mun system:

Return trip, looking good for re-capture as the ship\'s velocity is slower than Kerbin so it should catch us up:

Re-capture, a few small adjustments and Kerbin\'s gravity grabs my plucky Kerbanauts:

Re-entry, greeted by a sun-rise!

Final stats:

I really enjoyed this challenge, and I hope they give us some more planets/moons to explore asap.

[nivvydaskrl]

Ooh, very cool, Bedazzled. It looks like your periapsis was actually really close. :3 Good job!

[DeadlyPear]

I decided to try and attempt this challenge again, but sadly, the space dragon attacked me on my 3rd, and final, orbit around Kerbol \'til I met-up with Kerbin. I was so close D:

And I don\'t even have proof...

P.S. If I complete the challenge and have video proof, do I get a cookie?

EDIT: Working on the video now, I have gotten out of the Kerbin SOI and have orbited once. Just 3 more to go.

Here are my pariapsis and apoapsis

http://imgur.com/NtwN5

EDIT 2: Well, I give up, I have tried this 5 times, and each time, trivial mistakes screw me over. And it\'s not worth the hours or so of my time. I may try again tomorrow, I dunno.