> For the complete documentation index, see [llms.txt](https://guides.geospatial.bas.ac.uk/eo-training-resources/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://guides.geospatial.bas.ac.uk/eo-training-resources/level-0.md).

# Level 0

That is true. This [site](https://stuffin.space/) shows, how many are in there. Note, we are focused on satellites, facing Earth's surface, and monitoring various parameters of Earth's ecosystems. [Here](https://pudding.cool/2017/10/satellites) is a brief history of this kind of satellite. And another way around: [here](https://earthengine.google.com/timelapse/) you can check landscape changes over time, captured by Landsat (starting in 1984! - actually, the first Landsat satellite was put into orbit in 1972, but this app contains data starting 1984) all over the globe, [including Antarctica](https://earthengine.google.com/timelapse/#v=-67.2487,-66.06831,3.77,latLng\&t=2.96\&ps=50\&bt=19840101\&et=20201231\&startDwell=0\&endDwell=0,).

Now it is time for more in-depth reading. Be prepared for new [terminology](https://appliedsciences.nasa.gov/sites/default/files/2022-03/RS_Terminology.pdf)!

This [article](https://www.earthdata.nasa.gov/learn/backgrounders/remote-sensing) will give you a general understanding of technology, satellite types, and satellite imagery properties.

Alternatively, there is a selection of free self-paced mode courses to take:

* [Sections 1A and 1B of Fundamentals of RS](https://appliedsciences.nasa.gov/join-mission/training/english/arset-fundamentals-remote-sensing) by NASA ARSET
* [Land in Focus](https://eo-college.org/courses/landinfocus/) - Basics of Remote Sensing by ESA
* [Fundamentals of RS](https://eolearning.planetek.it/course/view.php?id=12) by Planetek


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://guides.geospatial.bas.ac.uk/eo-training-resources/level-0.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.