This is the companion reference for Session 3 of your Starboard training — satellite data. It follows the live session step by step. If you are a train-the-trainer, treat it as your teaching script; each section ends with a hands-on task to set for your trainees.

AIS tells you where a vessel says it is. Satellite imagery tells you where it actually is. When a vessel goes dark, or its AIS position looks wrong, imagery is the independent, non-cooperative check. In your trial you have Sentinel-1 SAR and Sentinel-2 optical imagery — the images themselves, which you read and reconcile against AIS by eye. This session teaches that manual workflow.

The session is hands-on. Have Starboard open on your Black Sea view and work along — each section has a Practise now task.

Session run sheet (≈90 minutes)

Time	Segment	You will
0:00–0:10	Why satellite, and SAR vs optical	Understand what each Sentinel sensor sees, and its limits
0:10–0:25	Getting imagery	Toggle on the imagery already flowing for the Black Sea; request imagery for an area outside it
0:25–0:55	Manual reconciliation	Align the clock, scan a footprint, and classify contacts against AIS
0:55–1:15	Spoofing tradecraft	Use the speed layer, AIS data points and identity history to catch manipulation
1:15–1:30	Close the loop & recap	Turn an alert into a satellite task

The slot is two hours; 90 minutes is the target, with headroom for questions and for imagery that takes a few minutes to load. Finishing early is fine.

1. Two sensors: SAR and optical

Starboard ingests imagery from the EU Copernicus programme's Sentinel satellites. The two you have behave very differently, and knowing which to reach for is half the skill.

	Sentinel-1 — SAR (radar)	Sentinel-2 — optical (EO)
What it is	Radar. Vessels appear as bright spots on the dark ocean	A photograph from space in visible light
Cloud & night	Sees through cloud, works day and night	Daylight only; blocked by cloud
Detection threshold	Metal-hulled vessels > ~25 m; small/wooden/fibreglass hulls may not return	Down to ~15 m; smaller vessels visible by their wake if underway
Resolution / revisit	20 m pixels; same strip every 6–12 days	10 m pixels; same strip every ~3 days
Best for	All-weather dark-vessel search — the workhorse	Confirming what a contact is once SAR says something is there

For the Black Sea and Sea of Azov this is a good-news story. Sentinel coverage is strongest over continental shelves and coastal waters, and the Black Sea is an enclosed, coastal sea — so your theatre is well covered, unlike the open ocean. Read more: Types of satellite data Starboard can ingest → · Application of SAR in Starboard → · Application of EO in Starboard →

Practise now. In one sentence each, say when you would choose SAR and when you would choose optical to check a vessel in the Black Sea at night under cloud. (SAR — it is the only one that sees through cloud and in darkness.)

2. Getting imagery — two paths

Inside the Black Sea and Sea of Azov, imagery comes to you. Continuous ingestion is already switched on for your theatre, so you do not request it — you just turn the layer on:

Open Map layers → enable Satellite data.
The Added satellite data panel appears on the left, listing the acquisitions available for your current time and area. Toggle a collection to show its footprint on the map.
If the panel is empty, there is no acquisition for the time and area you have set — widen the time window or check a different day.

Outside the Black Sea — for example, following a shadow-fleet tanker into the Mediterranean, or imaging a distant port — you request imagery on demand:

Draw and save an area of interest with the area tool.
Click Request satellite data (top right of the map).
Select your saved area, a date range of up to 31 days, and the image type (SAR or optical).
Imagery starts appearing within minutes. Note your request details — the beta tool gives little feedback, and very recent images (collected within ~4 hours) will not yet be available.

Practise now. Toggle on Satellite data over the Black Sea and open the Added satellite data panel. Find the most recent Sentinel-1 acquisition over the north-western Black Sea and display its footprint. Then, as a contrast, draw a small area off a port outside the Black Sea and submit a Request satellite data order for the last 7 days.

3. Manual reconciliation — the core skill

You have imagery but not automated detections, so you find and classify contacts yourself. The method is simple and repeatable:

Align the clock. Every image has an acquisition time. Set the time slider to that timestamp so the AIS positions on screen show where vessels were at the moment the image was taken. This single step is what makes the comparison valid — skip it and you are comparing an image to the wrong instant.
Scan the footprint. On SAR, look for bright returns against the dark sea; on optical, look for hulls and wakes. Zoom in — contacts are small.
Classify each contact against AIS:

What you see	Reading
Bright return with an AIS track sitting under it	Matched — a cooperative vessel; the image confirms its AIS position
Bright return with no AIS beneath it	Dark vessel — a vessel is present but not transmitting. The reason to be here.
An AIS track with no return where the image clearly covers that spot	Possible spoof — the vessel may not be where it claims (or is below the detection threshold / just outside the footprint)

Read the sea, not just the spots. SAR bright points are not always vessels — reefs, wind streaks, wave clutter, offshore structures and debris also return. Cross-check with the basemap, the vessel's expected size against the sensor threshold, and whether a nearby AIS track explains it. Optical is your friend for confirming what a SAR contact actually is. Read more: What are missing AIS tracks? → · Loitering with missing AIS →

Practise now. Take the Sentinel-1 footprint you displayed. Set the time slider to its acquisition time. Find three bright returns and classify each: matched, dark, or clutter. For any you call "dark", zoom in and look for a faint AIS track nearby before you commit.

4. Spoofing tradecraft — no detections required

Several powerful checks need only AIS and the map layers you already have. Use them alongside imagery.

Speed for selected vessels (Map layers) — visualises speed over time. Unnaturally constant speed and heading for days, in a smuggling area, suggests a manufactured track. This is how the sanctioned tanker in the DANUBE case was caught.
AIS data points for selected vessels — shows individual pings coloured by receiver source (satellite, terrestrial, vessel). A track that is dense with terrestrial pings one way and sparse, vessel-only pings the other way is a red flag. Combine with Full resolution AIS for maximum detail.
Vessels on land — a track crossing land needs no special training to spot. Switch the basemap to Satellite to rule out a legitimate inland waterway, then judge whether it is spoofing, GPS jamming, or a technical fault.
Identity history — paste a vessel's IMO into the search bar to reveal every name, flag and MMSI it has used. A rapid run of identities, or a jump to a blacklisted flag, points to deliberate obfuscation.

Practise now. Pick a tanker with a long Black Sea track. Turn on Speed for selected vessels and AIS data points, and drag the time slider across its voyage. Is the speed plausible throughout? Are the pings consistent, or do they thin out and change source? Then search its IMO — how many identities has it used?

5. Close the loop: alert to satellite task

You cannot watch every footprint continuously, so let alerts do the watching and use imagery to confirm. The pattern:

Set an actionable alert on a vessel of interest — most often stops transmitting AIS (see Session 1).
When it fires, note the last known position, course and speed, and project where the vessel would now be.
If that position is inside the Black Sea, check the continuously-ingested imagery for that time and place. If it is outside, submit a Request satellite data order over the projected box.
Reconcile the imagery against AIS using the method in section 3 — did the vessel really go dark, or is it spoofing?

Consolidate your knowledge

Run one full cycle unaided: display a recent Black Sea SAR footprint, align the clock, find and classify at least one dark contact, and confirm or dismiss it using optical or the spoofing checks.

Continue the training programme

← 2. Core platform use

VMSU — 3. Satellite data