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We have a lot of man made objects flying around the universe. Which one was the first one out of our solar system? How far away from the sun was it when it became "out of the solar system?

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    $\begingroup$ That depends on how you define "out of our solar system". If you want to get real nitpicky, we haven't gotten any objects out of our solar system yet. $\endgroup$ – called2voyage Sep 12 '13 at 21:45
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The rather funny thing about it is, that we don't actually know for sure that any man-made objects have already left the Solar system. There were many speculations on where our Solar system actually ends and the interstellar space begins, free of any influence from the Sun and its orbiting celestials. This is also the reason for this XKCD comic no. 1189 titled Voyager 1:

                                                    XKCD 1189 - Voyager 1

There were many claims before, that the Voyager 1 has already exited the Solar system and entered the interstellar medium, and the latest one from NASA, dating at the time of writing merely a month ago, August 15, 2013, quotes NASA's Voyager project scientist, Ed Stone of the California Institute of Technology in Pasadena, that had this to say:

Details of a new model have just been published that lead the scientists who created the model to argue that NASA's Voyager 1 spacecraft data can be consistent with entering interstellar space in 2012. In describing on a fine scale how magnetic field lines from the sun and magnetic field lines from interstellar space can connect to each other, they conclude Voyager 1 has been detecting the interstellar magnetic field since July 27, 2012. Their model would mean that the interstellar magnetic field direction is the same as that which originates from our sun.

Other models envision the interstellar magnetic field draped around our solar bubble and predict that the direction of the interstellar magnetic field is different from the solar magnetic field inside. By that interpretation, Voyager 1 would still be inside our solar bubble.

The fine-scale magnetic connection model will become part of the discussion among scientists as they try to reconcile what may be happening on a fine scale with what happens on a larger scale.

The Voyager 1 spacecraft is exploring a region no spacecraft has ever been to before. We will continue to look for any further developments over the coming months and years as Voyager explores an uncharted frontier.

enter image description here

This artist's concept shows NASA's Voyager spacecraft against a field of stars in the darkness of space. The two Voyager spacecraft are traveling farther and farther away from Earth, on a journey to interstellar space, and will eventually circle around the center of the Milky Way galaxy. Image credit: NASA/JPL-Caltech

But assuming these latest findings are trustworthy, then it's probably relatively safe to say that Voyager 2 has either already exited the Solar system, or is just about to, too.

NASA has published a convenient web page showing current distance from the Sun, the Earth and a few other details about the two Voyager probes. It has also this to say, indicating there might be a bit of a misnomer saying "out of the Solar system":

Voyager 1 and 2 are currently in the "Heliosheath" -- the outermost layer of the heliosphere where the solar wind is slowed by the pressure of interstellar gas.

Voyager probes on the Interstellar Mission

The image above also gives a bit more perspective on this problem of defining our Solar system boundaries, and @called2voyage is indeed correct in his answer, that this depends on how you define "out of our Solar system". So the proper answer to your question could perhaps be:

Awaiting conclusive readings from the Voyager probes themselves.

As you can probably imagine, the only way to know they have left the area of certain influence of the Solar system is that they are incapable of detecting any change for a longer period of time. So this will be a waiting game, and while some would love to jump the gun with sensational news, the truth is, we simply don't know yet. We do have some indication this might have happened already, but come tomorrow, we might receive changes in readings and will have to consider that they might not have left the Solar system just yet. Again!


This just in: Quick, cue that fanfares: It's Official! Voyager 1 Spacecraft Has Left Solar System

Seems everyone is reporting that as of September 12, 2013 (on the day of writing this answer), it is considered that Voyager 1 has officially been travelling through the interstellar space since the August 2012. For example, Space.com reports:

"Voyager has boldly gone where no probe has gone before, marking one of the most significant technological achievements in the annals of the history of science, and as it enters interstellar space, it adds a new chapter in human scientific dreams and endeavors," NASA science chief John Grunsfeld said in a statement. "Perhaps some future deep-space explorers will catch up with Voyager, our first interstellar envoy, and reflect on how this intrepid spacecraft helped enable their future."

And so does CNN. And there are videos even! Well, it's official then. Or is it? This latest announcement sounds so strangely familiar, doesn't it? We can all add another mark to that XKCD Voyager 1 comic, though. It's now off by at least one more time the Voyager 1 has left the Solar system:

                                                    XKCD 1189 updated

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    $\begingroup$ Great answer, seems like it is similar to the first crossings of the Atlantic Ocean, you won't really know where you are until you get far enough past so that you can look back and say, "so that is where I was!" $\endgroup$ – James Jenkins Sep 13 '13 at 10:39
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Depending on how you define "out of our solar system", no objects have gotten out yet.

Pioneer 10 was the first object to cross the asteroid belt, pass Jupiter, pass the Kuiper belt, and eventually reach the heliosheath. It was launched on March 2, 1972. It, however, has not crossed the heliopause. We lost contact with Pioneer 10 on January 23, 2003 because of loss of power to its transmitter. It was 12 billion kilometers from Earth at that point, and it will eventually leave the solar system.

No man-made object has yet crossed the heliopause or escaped the Sun's gravitational influence.

On August 25, 2012, Voyager 1 reached interstellar space, but it is argued that it may not yet have crossed the heliopause.

Sources:

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    $\begingroup$ Naturally, whether or not Voyager 1 reached interstellar space or crossed the heliopause depends on how you characterize the two, which is the entire problem right now. $\endgroup$ – called2voyage Sep 12 '13 at 22:06
  • $\begingroup$ I wonder if there are any updates? $\endgroup$ – uhoh Aug 24 at 8:15
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    $\begingroup$ @uhoh This is really a 2013-centric answer, as I believe it is now accepted that both Voyager 1 and Voyager 2 crossed the heliopause. I'd rather not update it though, as the first sentence really is key here. It may be in so-called interstellar space as far as radiation is concerned, but we're still learning a lot about the layers of our solar system. The hypothesized Oort cloud is beyond the heliopause. $\endgroup$ – called2voyage Aug 26 at 12:29
  • $\begingroup$ Sounds good, I see what you mean! $\endgroup$ – uhoh Aug 26 at 12:39
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I always thought the first man made object to leave earth and make it past Jupiter was a manhole cover. I assume its further out than Voyager now. Under ground nuclear tests launched a manhole cover at escape velocity, but this is all I know, hopefully an expert can clarify this.

update: Scott Manley has come to the rescue! In his video ** he describes the event in detail. He also shows a link to io9's No, a Nuclear Explosion Did Not Launch a Manhole Cover into Space who's title suggest that it didn't happen quite like this.

The explanation is that the original velocity estimation was not intended to be the starting point of a trajectory, and in Earth's surface atmospheric density it would not have survived:

It’s clear they weren’t on the same page. Brownlee wasn’t interested in what happened to the cap, and so pretended that the atmosphere didn’t exist. When the cap wasn’t found, he put it out of his head, figuring it had vaporized in the atmosphere. It was only later, when he both got credit for the world’s first space launch and criticism for not taking the atmosphere into account when he calculated the velocity of the cap, that he realized the legend of the cap that got launched at “six times the escape velocity from earth,” had taken on a life of its own.

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    $\begingroup$ Well, it's an urban myth, but at required near instantaneous acceleration to solar system escape velocity (over 42.1 km/s, or 26.2 mi/s!), frankly, that manhole cover would equally in an instant have evaporated. So much about why they never found it. But it's a cute myth, I like it. BTW, its speed was estimated by only appearing in air in a single frame on the film they made during the test. Allegedly, it was "going like a bat". :) See strangehorizons.com/2002/20021021/manhole.shtml for more info (best compile I could find, but read all of it, there's more fun to it) $\endgroup$ – TildalWave Feb 11 '15 at 23:23
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    $\begingroup$ Biff - To supplement @TildalWave's informative link, I added a link to the Wikipedia page to provide some context. Feel free to roll it back. I'll also add in the I-wasn't-the-downvoter disclaimer in this comment, despite the circumstantial evidence against it. $\endgroup$ – HDE 226868 Feb 12 '15 at 0:20
  • $\begingroup$ This does not provide an answer to the question. To critique or request clarification from an author, leave a comment below their post - you can always comment on your own posts, and once you have sufficient reputation you will be able to comment on any post. $\endgroup$ – HDE 226868 Feb 12 '15 at 1:19
  • $\begingroup$ @HDE226868: How does this not provide an answer? (I'm not saying it's a correct answer.) $\endgroup$ – Keith Thompson Feb 12 '15 at 2:39
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    $\begingroup$ The math on the single frame yielded a minimum velocity > earth's escape velocity. I agree though the most likely result was burnup on the way up. $\endgroup$ – Joshua Oct 4 '15 at 0:09

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