Visual graph of active interplanetary probes over 50 years Options

[Mark6]

Active Interplanetary Probes At Any Given Time.

This is a timeline of every space probe that ever made it out of Earth orbit and to another celestial body. Its purpose is to visualize, as you scroll up and down the page, how the flotilla of Earth's emissaries throughout the solar system has grown and shrunk with time - but mostly grown.

[elakdawalla]

Mark6, this is an extremely simple and elegant way of plotting out the history of interplanetary space exploration -- I have been wanting to come up with something like this for a long time, but always wound up with too complicated a structure and never came up with anything successful. Very strong work!

Two things that this doesn't capture (and, not coincidentally, two reasons I have never come up with a visualization that worked) are lunar exploration and the difference between spacecraft that are cruising or en route and spacecraft that are at their destinations actively doing science. The rules are different for lunar exploration because cruises are so short and because there were so many missions early on. It would be easier if there were a straightforward boundary between missions that were mostly pre-Apollo engineering tests (and could therefore be ignored) and missions that really returned science. Perhaps there is; I am too ignorant about early lunar exploration to draw that boundary.

--Emily

[stevesliva]

Lunar orbits require a lot of fuel to remain in orbit, as well, so I'd guess they'd all look very brief.

It's amazing (and sad) that Cassini is moving into the #3 spot as 3rd oldest operational spacecraft not orbiting earth! Points to a lack of RTG powered missions, I suppose. But Stardust is long in the tooth as well... I feel old.

I also notice you have a number of failed-after-cruise missions, but not the also disappointing failed-at-launch or soon afters like CONTOUR or Mars 96. They weren't active, but they tried!

Genesis is missing.

[elakdawalla]

Well, Cassini's old because it takes a long time to explore the outer solar system. That's one reason I always wanted to try to differentiate spacecraft that were cruising from spacecraft doing science -- not many of the quarters from 1997 to 2004 should really "count" for Cassini.

A slightly different way of organizing the same chart might be to sort the positions left to right by destination (using the same destination groupings as you already developed), in order of decreasing cruise time. That would keep all those long-lived outer-planets missions constantly to the left, from their inception, and shift the briefer Mars and Venus stuff to the right; it might help visualize the boom-and-bust style of Mars and Venus exploration.

--Emily

[Mark6]

Mark6, this is an extremely simple and elegant way of plotting out the history of interplanetary space exploration -- I have been wanting to come up with something like this for a long time, but always wound up with too complicated a structure and never came up with anything successful. Very strong work!

Thank you!! Coming from you, this is more praise than I dared to hope for.

Two things that this doesn't capture (and, not coincidentally, two reasons I have never come up with a visualization that worked) are lunar exploration and the difference between spacecraft that are cruising or en route and spacecraft that are at their destinations actively doing science. The rules are different for lunar exploration because cruises are so short and because there were so many missions early on. It would be easier if there were a straightforward boundary between missions that were mostly pre-Apollo engineering tests (and could therefore be ignored) and missions that really returned science. Perhaps there is; I am too ignorant about early lunar exploration to draw that boundary.

I think Moon missions are not well suited for this kind of graph because almost all of them were short. I decided to make the website when I visualized a gradual build up of the "flotilla", with newer spacecraft coming on line as older ones drop out over the years. With Moon you have a flurry of activity in 1960's and early 70's, almost every one of them fits in a single quarter, then nothing for 18 years, then a few longer missions but still with no overlap at all. It is just not as visually appealing.

The difference between spacecraft that are cruising or en route and spacecraft that are at their destinations actively doing science is a bit tricky because something like Deep Impact or Voyagers are at their "destinations" only for a few days out of years, yet they are actively doing science. I suppose since every row takes up a quarter of the year, it is legitimate to highlight the quarters during which encounters occured.

[Mark6]

A slightly different way of organizing the same chart might be to sort the positions left to right by destination (using the same destination groupings as you already developed), in order of decreasing cruise time. That would keep all those long-lived outer-planets missions constantly to the left, from their inception, and shift the briefer Mars and Venus stuff to the right; it might help visualize the boom-and-bust style of Mars and Venus exploration.

I can try. This was done with a PHP program; I will have to think how to modify it to do the grouping. Now that I think of it, multiple periods of activity, like Voyager 2 at each planet, will be more difficult to code; I might make just two portions (cruise/active), at least at first.

I did not include Genesis, Helios, or SoHo because they are all solar probes. Actually, no real reason why I should not -- and that will be quite easy.

[Tom Tamlyn]

Thanks for your very illuminating chart.

Two things that this doesn't capture (and, not coincidentally, two reasons I have never come up with a visualization that worked) are lunar exploration and the difference between spacecraft that are cruising or en route and spacecraft that are at their destinations actively doing science. T

Perhaps you could use cross-hatching to indicate active science operations, although you'll have to decide whether operation of particles and fields instruments during interplanetary flight qualifies.

TTT

[tedstryk]

This is really cool.


I hate to be picky, but Mariner 5, Mariners 6 and 7, and Mariner 4's 1967 operations are missing.

[Mark6]

This is really cool.


I hate to be picky, but Mariner 5, Mariners 6 and 7, and Mariner 4's 1967 operations are missing.

Fixed. That was easy; sorting columns will have to wait a few days.

Don't feel bad about being picky -- I do not want to have errors in the page!

[NGC3314]

Thanks for your very illuminating chart.



Perhaps you could use cross-hatching to indicate active science operations, although you'll have to decide whether operation of particles and fields instruments during interplanetary flight qualifies.

TTT

As a deep-sky astronomer, sometimes I think planetary-science types are a different species. Why wouldn't particles and fields, heliospheric studies via Lyman alpha, or UV astronomy qualify as science operations? (I was struck to find, only recently, that the Lyman-alpha measurements during interplanetary cruise go back at least to Venera 4).

[Greg Hullender]

Ideally, I think you'd want the width of each column to correspond to the quantity of data being returned. Something like New Horizons, which spends most of cruise in hibernation, really isn't doing much science right now, but other probes might well be.

Of course that won't be a simple table.

--Greg

[elakdawalla]

Greg, those kinds of great ideas are a perfect example of why I was never able to complete a chart like this. Sometimes, in order to get a project done, you need to throw out most of your great ideas and just keep it simple!

This chart evokes one of the greatest posters I have ever purchased, the Rand McNally Histomap of World History, which plots the rise and fall of civilizations as expanding and contracting shapes on a vertical chart with time:
http://www.kk.org/cooltools/archives/000453.php


--Emily

[ustrax]

Emily...that is really an impressive chart!
Truly my kind of stuff...
Is Portugal included? If not I won't buy it...

Mark6...your work is just superb, clearly shows how evolution is taking place in the space exploration field...

[brellis]

Regarding Emily's comment about the long cruise phase for outer planet missions - and Mercury MESSENGER, for that matter:

I recall with great fondness checking the Cassini Status Reports during the cruise phase. One of their standard statements was very soothing to see - "the spacecraft is in excellent health, and all monitored systems are functioning normally" - something like that.

Maybe the type face could be bold when it reaches its destination. That would be another way to illuminate the status of the flotilla. For that matter, spacecraft that are floating around at the end of their successful missions might be another one to put in - have them reduced to mini/micro size, perhaps.

[Greg Hullender]

Emily: Yeah, the best is the enemy of the good. However, that chart you linked us to is more or less what I had in mind, except rather than being fixed width, I was thinking of letting it gradually get wider to reflect the total amount of data sent by all probes combined (probably use log scaling).

--Greg