Getting Started with Hydrosat Data

Hydrosat imagery products are available through a web application and SpatioTemporal Asset Catalog (STAC) API. To access the imagery catalog, you will need an account.

Prerequisites

1

Request an account and get approved for access.

Fill out the Request Access form on our website.

2

Receive your invitation email.

Once your account has been created, you will receive an email from support@hydrosat.com with your username and temporary password. Check your spam folder if you don't see your invitation email.

3

Reset your password

Follow the instructions in the email to log in with the temporary password and choose a new password. You have 7 days to log in and reset your password. If your temporary password expires, contact Support to get a new temporary password.

4

You're all set!

Once you've reset your password, you will be able to use your new account to log into the Discovery Portal. If you need to generate API credentials for use with our STAC API, follow the instructions for managing API clients.

Ordering Data

Please speak with your organization point of contact to define and submit your order request.

VanZyl-1

VanZyl-1 (VZ-1) is Hydrosat's first pathfinder mission. Launched in August 2024 on the SpaceX Transporter-11 rideshare, VZ-1 is a technology demonstration and proof of concept for our forthcoming constellation that will redefine space-based thermal infrared remote sensing by enabling daily continuous monitoring of any location on Earth.

VZ-1 hosts two imaging payloads: Hydrosat’s first-generation, proprietary Longwave InfraRed Imager (LIRI) along with its Visible and near-InfraRed Imager (VIRI). LIRI acquires thermal infrared (TIR) imagery at wavelengths between 10.6 and 12.51 micrometers. VIRI images in 7 spectral bands ranging from 458 to 900 nanometers. VZ-1 imagery is acquired mid-morning local time.

VanZyl-2

Hydrosat's second pathfinder mission, VZ-2, launched in June 2025 on the SpaceX Transporter-14 rideshare. VZ-2 hosts the same two sensors as VZ-1, but acquires imagery in mid-afternoon local time.

Use Cases

Hydrosat users leverage high-resolution thermal data for a variety of use cases, including:

Agriculture

Urban Heat

Wildfire

Energy

Oceans

Defense & Intelligence

Weather Forecasting

Forestry

Biodiversity

Requesting Support

If you run into any problems, please get in touch with us at support@hydrosat.com. We’ll get back to you as soon as we can. Our support team is available 8:00 am to 4:00 pm Pacific time on weekdays.

The Discovery Portal is a web interface for visually browsing and downloading Hydrosat's satellite imagery catalog and complements the Discovery STAC API.

Interested in getting access to the Hydrosat Discovery Platform? Fill out the Request Access form on our website.

If your Discovery Platform account is configured to allow data downloads, your access is based on areas of interest and/or specific scene IDs. The Discovery Portal includes some helpful tools to help you locate, search, and understand your downloadable data.

For help locating downloadable data via the STAC API, check out this separate article.

Viewing Downloadable Data

Imagery Searches

If you have access to downloadable data, the Downloadable toggle is available on the imagery search bar. Combine the Downloadable toggle with additional search filters, such as Acquisition Date or Cloud Cover , to find results for a subset of your downloadable data.

A Downloadable search includes results based on area of interest and specific scene ID, depending on how your account is configured.

Download Access Areas

For accounts with area of interest-based download access, you can view your Download Access Areas on the map. When using the Downloadable search toggle, as discussed above, the search automatically looks for results matching your Download Access Areas.

Creating an API client is required to use Hydrosat's Discovery STAC API. This article covers the workflow for managing API Clients in the Discovery Portal.

Viewing the API Clients Management Interface

The API Clients management interface is available only to users on your account with the Org Admin role.

To view the Client ID interface, click your user avatar in the top right corner of Discovery Portal and select Account.

Users with the requisite permissions will see the API Clients section on the Account page.

Creating an API Client

Each account is limited to 4 total API clients, so consider this limit when creating new API clients.

1. Click New API Client on the right side of the API Clients section.

2. Provide a name for the API client that is easily recognizable to you and other Org Admins. Name is required.

3. (Optional) Provide a description.

4. Click Create API Client

5. Immediately upon creation, the client secret for the API client is displayed. This display is only temporary. Store the client secret in a safe and secure location in your environment as you will not be able to retrieve it from Discovery Portal in the future.

Hydrosat's Discovery STAC API requires a bearer token for authentication and authorization.

This article covers the process of using a client ID and secret pair to generate a bearer token and then including that bearer token in requests to the STAC API.

For documentation on how to create an API client ID and secret, view the Managing API Clients article.

Using a Client ID and Secret to get a Token

When creating an API client in the Discovery Portal, you will be issued a client ID and client secret for that API client.

The client ID and secret are unique credentials that allow the client to generate a temporary bearer token which provides access to use the API with any permissions provided to that client.

The client can request a valid token by submitting its client ID and secret in a form POST payload to the following token url:

The response contains the values shown below, including the amount of time the token will live before expiring, in seconds. Because a token is only temporarily valid, the client must manage getting refreshed tokens regularly in order to have consistent access to the API.

'Get Token' Example

The example below assumes that the user has stored their API client ID and secret in a separate file called creds.json with the following structure:

For security, we suggest setting credential file permissions to 600 (chmod 600 creds.json) so that only the owner has read and write access. Consult with your organization's security team to ensure you are complying with preferred methods for storing and accessing API client credentials.

The Python example below covers using the credentials stored in creds.json to generate a new token for use with the Hydrosat Discovery STAC API and storing the resulting token in the access_token variable.

Using the Token to Make a STAC Request

Once the client has a valid token, it can make requests to the STAC API as normal.

In the below example, the token is stored in the access_token variable from the previous code example and is used to make a request to the /collections endpoint using the requests Python library.

Unauthenticated Requests

Unauthenticated requests to the STAC API will return an error (401 Unauthorized Error)

For lengthier examples and next steps, please see our code examples in Github.

Visit our example code Github repo for helpful tutorials for using our STAC API and imagery.

Visit our status page and sign up for notifications to get the latest information on our STAC API availability.

Hydrosat's Data Discovery STAC API is available at https://stac.hydrosat.com/. The STAC API requires authentication using a bearer token.

SpatioTemporal Asset Catalog (STAC) API

This page includes high-level information on the basic features of the API and provides examples for a few methods of working with it.

Through Hydrosat's STAC API, you can search for data that meets your needs. Data are stored as Cloud-Optimized GeoTIFFs (COGs), which means you can either download the full files or stream only the parts you need using standard web requests.

Learn more:

• STAC (SpatioTemporal Asset Catalog): stacspec.org

• Cloud-Optimized GeoTIFFs (COGs): cogeo.org

While you can use the STAC API directly, we recommend using one of the following tools to make it easier:

• Python library: pystac-client documentation

STAC API Endpoints

STAC Catalog Structure

Hydrosat's STAC catalog is organized into four collections.

Each collection contains a series of items representing individual scenes. Within each item, you will find metadata and links to associated imagery.

STAC Query Examples

pystac-client

We recommend using the pystac-client Python library. This library is specifically designed to interact with STAC catalogs and APIs. Complete documentation for this library can be found here. More examples with pystac are included in our full Github examples.

import pystac
from pystac_client import Client

# Connect to the STAC catalog.
# See our page on authentication for how to set up your headers.
catalog = Client.open('https://stac.hydrosat.com/', headers=headers)

# Search for Level-2 data intersecting southern Australia from 19 April 2026
search = catalog.search(
        collections = ['vz-l2'],
        bbox = [140.173825, -37.63983, 149.28178, -34.929824],
        datetime = ["2026-01-19T00:00:00Z", "2026-04-19T00:00:00Z"]
    )

# Print a list of STAC items returned from the search    
items = list(search.items())
print(items)

curl

The STAC server can also be queried directly from your terminal using curl. For example, you can use a POST request to perform a query, specifying the search parameters as JSON-formatted raw data. For more information, please see the curl docs.

curl -X POST \
--header 'Content-Type: application/json' \
--data '{
    "collections": ["vz-l2"],
    "bbox": [140.173825, -37.63983, 149.28178, -34.929824],
    "datetime": "2026-04-01T00:00:00Z/2025-05-01T00:00:00Z"
}' \
https://stac.hydrosat.com/

If your Discovery Platform account is configured to allow data downloads, your download entitlements are based on areas of interest and/or specific scene IDs. If you already know what your entitlement areas of interest (Download Access Areas) or scene IDs are, you can use that information to query data via the STAC API.

For help locating downloadable data in the Discovery Portal, check out this separate article.

If you don't know what your download entitlements are, you can look them up using Hydrosat's Accounts API.

If you would like to get access to downloadable data, contact our sales team.

Using Accounts API

Accounts API uses the same bearer token Authentication and API credentials as the STAC API.

Use the following endpoint to GET the active access policy for your account, which includes information about your download entitlements.

https://accounts.hydrosat.com/v2/me/access-policies

The polygons for area of interest-based download entitlements are listed within product_entitlements and scene ID-based entitlements are listed within scene_entitlements. The product_entitlements and scene_entitlements also include information about which STAC collections are you entitled to download from.

A product_entitlements example with a single polygon areas_of_interest is shown below.

A scene_entitlements example containing 2 scene_ids is shown below.

Level-1 Imagery

The Level-1A data product is the least processed of the available imagery. It includes processing applied onboard the instrument, such as time delay integration and non-uniformity corrections, as well as co-registration of sensor bands and georegistration. The full swath data is provided to users in image space with no resampling. Level-1A pixel values represent top-of-atmosphere (TOA) radiance [W/m²/sr/μm].

The Level-1B product includes converting the radiance values to TOA reflectance (VIRI) or brightness temperature (LIRI), clipping the VIRI data to the extent of the LIRI swath, generation of a cloud mask, and orthorectification.

Each STAC item includes several assets representing the individual data and metadata files associated with the scene. Items from different collections contain a different set of assets, as defined below.

L1A VIRI TOA radiance values can be converted to TOA reflectance by applying the per-band LEVEL1_REFLECTANCE_SCALING coefficient in the companion L1A metadata (MTA) file.

L1A LIRI TOA radiance values can be converted to brightness temperature using the following equation:

where K₁ and K₂ are per-band LEVEL1_THERMAL_CONSTANTS from the L1A MTA file, and L represents scaled radiance.

L1B VIRI reflectance data can be converted back to TOA radiance by applying the per-band LEVEL1_RADIANCE_SCALING coefficient in the companion L1B MTA file.

L1B LIRI BT values can be converted back to TOA radiance using the following equation:

where K₁ and K₂ are per-band LEVEL1_BT_TO_RADIANCE_CONSTANTS from the L1B MTA file.

The Level-2 product includes radiometric terrain corrections and conversion to surface reflectance (SR) and land surface temperature (LST).

Level-2 assets include per-band SR and LST COGs (and more).