View Full Version : Scanning a Planet Before Landing

07-03-2016, 05:34 AM
One of my MCs is about to crash on a planet in order to escape an ion storm. While he's trying to figure out the best course of action, his spaceship's computer displays vital information on the planet in question. I have the MC note that "everything checks out--gravity, atmosphere, and so on." But I decided I don't care for the vague "and so on." I'd like to provide a couple of details instead, but I'm drawing a blank. Besides gravity and atmosphere, what other elements might be scanned for when determining whether a world is habitable or not? What's absolutely crucial for him to know before he lands?

I thought maybe "temperature range" or "weather patterns," but not sure if those are too similar to "atmosphere"?

If it matters, the world is inhabited by a civilization that's similar to Earth, circa 1930s/1940s. The story is a sci-fi romance with a touch of dieselpunk.

Any ideas?

07-03-2016, 05:43 AM
Landing zone, water, if it's an ion storm, either caves or a magnetic field, ...

You might have him dip below the magnetic field giving him more time to assess the best place to land.

Dennis E. Taylor
07-03-2016, 08:22 AM
Atmospheric composition (too much CO2? Not enough oxygen? Presence of toxic gasses?).
Temperature range.
Solar output: too much UV? Too much radiation?
Wind speed (he could be in the middle of a hurricane).
Presence/absence of water?
Any life? Especially the kind that eats first and asks questions later?
What's the terrain like? Is he in the middle of a bog? Muskeg?

07-03-2016, 01:04 PM
If your in a space craft about to crash on a unknown planet , I don't think you would be asking too many detailed questions . Your mind would be on smashing in to the ground. You would need to know how this craft lands . Is it pod like the present day astronauts use . Would it use a parachute , land in the sea or on land . The speed of descent would be a big consideration and can it be controlled. Something more sophisticated could go into a low orbit, so you are not actuly crashing , it would be a searching for some suitable landing spot . You could have a large balloon inflate above the craft and the terrain would be important , mountainous could be a problem . I am guessing your astronauts will survive. So I don't think giving lots of details from gauge readout, only to confirm things are suitable, would be very exciting .

07-03-2016, 05:19 PM
It's a very sophisticated spaceship, with just the one man aboard. At first, he's planning to land in an isolated area, just to escape the ion storm that's passing through the system. But things go wrong and he ends up crashing in a forest on the outskirts of a major city. The ship has a landing shield to protect it from the heat of reentry, and a cloaking shield, to prevent the locals from spotting them. No parachutes or anything like that. In this particular scene, he's doing a quick check to be sure the planet is safe to land on, so I just need a couple of things he'd scan for, prior to initiating landing procedures. It's a single sentence, since he doesn't have a lot of time to worry about whether the planet is suitable, but I'd still like it to ring true.

I'm thinking he might scan for the presence of potable water and food sources, but what would you call that? Edible vegetation? Something else? Can that even be checked from orbit, or would he need to just take his chances?

07-03-2016, 05:31 PM
Computer, what's the status of that planet ahead? Give me the short version.

It depends on where you land Dave. It was surveyed 79 years ago by the Perseus Expedition Probe and was tagged for a planned lander mission and possible colonization. It ranges from polar ice caps to a tropical equator. Atmospheric sensor logs from the Perseus show the likelihood of plant and animal life high most likely without any advanced sentient species. Would you like me to plot a landing site?

07-03-2016, 07:29 PM
If your ship is crashing into a forest near a city , that would in itself suggest all the things you need for life exist. In War of the Worlds the invaders were killed by bacteria , harmless to humans but deadly for the aliens . So a chemical and bacterial analysis of the air might be useful .

07-03-2016, 08:12 PM
Like Angry Guy said, CO2/Nitrogen/Oxygen balance would be helpful for vegetation- if it's off there's probably no vegetation that would be edible. Potable water would be albedo (how much is reflecting off of pools and ponds) and I think spectroscopy (how much humidity is in the atmosphere) your MC is far away. If your MC is close enough to orbit s/he can probably eyeball it from the amount of blue/green. Hope this is helpful!

07-03-2016, 10:01 PM
Chemical and bacterial scans sound good, thanks. At the moment, the MC isn't in orbit, but he will be shortly. I think I've got the sentence working now, but I'll listen to additional suggestions if anyone has them. Thanks, folks!

07-05-2016, 11:59 PM
What's absolutely crucial for him to know before he lands?

For me, it's where the nearest McDonald's is for my sweet tea fix. But my real question would be "What use is any information if he's crashing?" It's not like he has a choice, does he? Flat ground with no obstructions and a giant box of styrofoam peanuts would about cover it.


07-06-2016, 06:32 AM
Well, if he is about to crash land on a planet that appears to have all the ingredients for life, he would also scan for life signs. You said the planet had a native civilization already established with a pre-WWII technology level so his scanners might register a power grid or even pick up radio broadcasts. Well, the first thing your MC better do is find the right clothes to fit in with the locals. while he's looking for spare parts to fix his ship. Sounds like a good read. Good luck with it.

07-06-2016, 05:18 PM
Jeff, actually, he does have a choice. He's trying to escape an ion storm, so he's looking for someplace to land. Right now, the computer only finds one habitable world within range and he goes there, but the planet is interdicted because the inhabitants don't have advanced technology yet. He only crashes when the storm catches up to him as he's trying to land. However, I'm thinking it might actually be more interesting if he has a choice between a desolate, barely habitable planet that's not interdicted (because it's not inhabited), and the world that's lush and green and beautiful, but that's forbidden because it's home to a pre-spaceflight civilization. His decision would add some tension to the opening scene, which is always good!

Realityfix, thanks. Those would be some good things to look for, except he already knows the planet is inhabited, because the ship's computer warns him the world is interdicted due to its low-tech civilization. He does a fair job of fitting in after crashing. He gets a job at a local university, as a science professor. He even falls in love with one a local woman, which leads to her having to decide whether to help him fix his ship or not, knowing full well that once it's repaired, he'll leave her backwater world forever. Lots of tension and angst! (I'm always so cruel to my characters, LOL.)

07-07-2016, 03:47 PM
Jeff, actually, he does have a choice. He's trying to escape an ion storm, so he's looking for someplace to land. Right now, the computer only finds one habitable world within range and he goes there, but the planet is interdicted because the inhabitants don't have advanced technology yet. He only crashes when the storm catches up to him as he's trying to land.

Might change his decision process but, again, he seems to have a single option here. Land or die. Also, if he's not supposed to land, planet being "interdicted" and all, why does he crash while trying to land?

Now, your story requires he land, manage to reach civilization and fit in, so those points are moot. Choosing an area where discovery of the ship would be hard or impossible would seem appropriate, such as ditching at sea or in rugged mountains that would likely have no inhabitants or visitors. But he has to be close enough to make it to civilization for your story. And he has to maintain the ship relatively intact to be able to repair it and leave (presumably with the love of his life at his side...).

There are plenty of areas on this planet where you could drop a space ship and nobody would know, even if they lived right over a hill. You may need to find a way to camouflage the ship and crash to prevent discovery, but it really depends on how your story unfolds.


07-07-2016, 05:27 PM
I'm going to change it so he has a choice between the interdicted planet and an inhospitable world. Everything else you mentioned, I've got covered.

The reason he crashes, as opposed to simply landing, is because the ion storm he's trying to escape interferes with the ship's systems, knocking out the autopilot/computer. Therefore, he has to land manually, which he hasn't done since graduating flight school. Plus, the controls aren't responding correctly, due to damage from the ion storm, so he ends up coming in too fast and crashes.

If he ditched the ship in the ocean or mountains, he wouldn't be able to repair it and eventually go home. I arranged it so he crashes deep in a forest near the edge of a major city, so he's close enough to walk to the city after the crash. He ends up living and working in the city, but he's close enough to still make repairs on his ship in his spare time. Does that work?

The ship has a cloaking shield that he just barely manages to keep online during his descent, so the ship isn't visible while it's coming down above the city.

He uses a special technology to keep his ship hidden: a subliminal field, which subtly nudges people away from the ship, without them realizing it. So instead of a bunch of hikers stumbling over the ship come summertime, anyone who gets close enough just wanders around the ship, never realizing they're being herded away from something. This comes into play later, when the MC is attacked and has to run for her life. She goes to the ship to hide, knowing the subliminal field will keep her assailant from finding her. (Of course the subliminal field has a major flaw, so things get interesting. . . .)

That just about covers everything, right?

07-07-2016, 11:33 PM
Immediate survival:

- radiation
- temperature
- atmospheric pressure
- terrain
- extreme wind

Long-term survival:

- liquid water
- edible food supply
- toxic substances: not necessarily gases in the atmosphere, but could be pervading all water supplies
- aggressive animals
- seismic activity
- extreme tides
- extreme seasons

Radiation is the major non-atmospheric one you've left out. Some stars produce deadly radiation that would kill you in a few hours. In fact, our star does too, but we have an ozone layer to block it. Some planets might not.

07-08-2016, 01:53 AM
Excellent points, morngnstar! Thank you.

07-08-2016, 06:53 AM
This story line of yours has a lot of possibilities. Let me share some. Does anyone else know where your MC has gone? Will a search party be looking for him or is he wanted by the law? After your MC blends in and creates a life for herself(?), if others from her world come barging in looking for her she may be forced to rethink her loyalty to her own people especially if those who came to look for her are cruel and sadistic to the locals. Another possible subplot is what if something happens that forces her to use her advanced technology to resolve a political conflict that almost turned to war. Would she do it and change the course of history for that planet or would she stay out of it and let innocent people die? Is your MC a strong female? She could upset the cultural balance of the planet if it is a patriarchal society where men dominate. Wow, you have some serious possibilities to string this out as a series or a trilogy!

07-08-2016, 11:27 AM
A lot depends on the technology available to your character and in particular how advanced his ship's computer is. A relatively low technology computer would have lots of gauges and information. It doesn't know what is important so displays everything. As computers become more advanced they tend to filter out the information that they present to the user.

Think of it like a car. Rewind a few decades and our cars gave us lots of information about the state of the engine. We had oil pressure gauges and water temperature gauges. Most modern cars don't have those any more. Instead we have warning lights which come on only if the computer detects that there is a problem.

If your MC's spaceship is advanced enough to visit planets that need to be scanned, that means that it is probably capable of FTL travel. That almost certainly means that the computers will be a long way past the banks of gauges and dials that filled the cockpits of the Apollo spacecraft or the space shuttle. In all likelihood, the computer will be able to work out what the MC needs to know and will give him only that information and no more. Something like "habitable and with a breathable atmosphere."

It's the original Star Trek problem. We tend to think that the future will be incredibly complicated with lots of flashing lights, gauges, dials and a computer that only the science officer can use. But everything from history shows us that technology gets easier to use as it gets more mature.

In your scenario, I would try to imagine what the spaceship designers would think that their spaceships would need. Crashing into a planet is one of those fairly standard things that spaceships tend to do, particularly in fiction. So it's safe to imagine that the spaceship would be designed to help the occupants survive the crash as best as possible. The computer would give the minimum level of information that the pilot needed for the landing, especially as the pilot would have other things to worry about at the time. I can't see the spaceship designers wanting to overload the pilot with lots of unnecessary information about the planet when he ought to be doing some steering or getting himself into an escape pod.

Put it another way. There are several safety systems which are triggered automatically if we crash a modern car. Airbags deploy. Seatbelt pre-tensioners fire, pulling us back into the seats. The car's bodywork deforms to form crumple zones. In some cars, the computer takes over the emergency braking from the driver and applies maximum braking. The hazard lights might go off. Some cars would even send a message to a control centre to say that they're having a bit of a moment.

All of this happens without the car asking the owner's permission, or giving any warning that it is about to happen. The car only displays warning information if it judges that the driver needs to know it. If cars can do that now, what do we think a FTL spaceship will be able to do?

07-08-2016, 05:22 PM
Once, you make some excellent points! I've tried to extrapolate their advanced technology based on current trends, such as AI computers with vocal interfaces. It's why the MC talks to the computer in the prologue. I've received a few critical comments about the fact that he talks to the computer while trying not to crash his ship, but given current trends in technology, it seems like it would be natural for him to ask the computer what's happening, and for the computer to respond (vocally) with the information he needs. I mean, if I can ask my Amazon Echo about the weather each morning, why shouldn't the MC be able to ask his ship's AI about the planet he's about to crash on?

There's supposed to be an autopilot that will land the ship safely, but because of the ion storm frying the ship's systems, the computer and autopilot go offline, so the male MC is forced to use manual controls to land the ship--something he hasn't done since flight school. He wants to land in an uninhabited area, like the deserted northern continent, but instead, he buzzes the top of a skyscraper on his way in and realizes he's about to crash in the middle of a city. At the last minute, he's able to steer towards a forest at the edge of the city instead, so his ship remains hidden. I end the scene right as he crashes, but I may go back later and have him mention that airbags, or a forcefield, or some other form of safety mechanism that automatically deployed, even though the computer was fried. Otherwise, he'd never have survived the crash-landing. He didn't need medical attention, just suffered a few bumps and bruises, so you're right, there had to be safety precautions that kicked in. I don't want to go into too much detail about the crash, but perhaps the female MC will ask him how he survived, years after the fact, and he can casually mention the safety precautions that automatically protect the occupants of the ship during a crash. Thanks for the suggestion!

Realityfix, good questions! Many will be answered, either in the course of this story, or in the sequel, which I've just barely started working on. Still don't have an outline yet, and I've only a vague idea of where I want it to go with it, but I've written a few scenes. The ship crashing is actually the prologue of the first novel, and it's a different POV than the bulk of the story. The prologue's MC is the man from another world, while the main story is from the POV of a woman who's native to the planet. (Although, I am considering the possibility of adding a number of scenes from his POV, since the novel is woefully short at this point, only 65,000 words, when I'd like it to be at least 90-100,000. If I can't think of a good subplot to weave in, I'm either going to have to add scenes from the sequel to make it longer, or else add a second POV.)

The male MC isn't wanted by the police, but he's next in line to be the dominus of the Regime, a spacefaring civilization that spans hundreds of systems and thousands of worlds. It's sort of like a monarchy, his older brother is slated to be the dominus after their father is killed. He feels his presence isn't required, and he hates his people's stuffy traditions, and etiquette, and their utter lack of strong emotions (he's something of a throwback, able to feel deeply, whereas most of the upper class has bred out "inferior" emotions), so he basically runs away, in the hopes of "finding himself." His people don't come looking for him until the sequel, when his brother dies and he's needed to rule, but there's definitely the possibility of his people interfering with the world war that's being fought on the world he crashed on. At the beginning of the sequel, the male MC is captured and tortured by a military leader who finds his spaceship and realizes he's from another planet, and desperately wants advanced technology to help them win the war. The MC doesn't tell them anything, but they probably glean a few ideas from examining his ship. I'm planning for the military leader to stage a coup, taking over his country, at some point. Perhaps he'll use the advanced tech to try and win the war, and so the "aliens" will finally step in and stop the war, since it's being fought unfairly with their tech. I'm absolutely terrible when it comes to writing military strategy and politics--the first novel is supposed to be a sci-fi romance, not a political/military story!--so I've been trying to avoid a plot that gets into the politics of the world war, but it may be unavoidable.

It's not a patriarchal society. The country the female MC lives in is vaguely communistic or socialistic in nature, very military oriented, with a general as their leader. The female MC is a strong woman, but she's not the type to try and effect major changes or overthrow the government. She was orphaned as a toddler and raised by the state, which means she was essentially brainwashed her whole life to believe the state is always right, the state wants what's best for the people, yadda-yadda-yadda. She starts realizing that the state lied to her, first when her best (and only) friend dies and she's chastised by authorities for mourning her loss, and later, when she visits another country on a secret mission and sees for herself that the "enemy" she's been raised to hate is just normal folks. She comes to realize that everything she's been taught is wrong, but she lacks the courage to do anything about it. At least until the sequel, when she finds out she's pregnant and doesn't want her baby to be brainwashed the way she was. That finally gives her the courage to defect. I've been thinking she might need to find that courage in the first book, rather than the sequel, but I can't figure out how to include everything that needs to be included for that kind of subplot, without making the story way too long.