Throughout your journey through a sector, upon arriving at a beacon, there will sometimes be a environmental hazard present, which usually impedes your ship in some fashion. Do note that any other ships at the beacon will, with some exceptions, receive the exact same effects.
Class-M Red Giant StarEdit
Beacon coordinates appear to be very close to a nearby sun.
The game will warn you with a "Solar flare imminent" message before it happens, upon which random fires will be set in the ship, dealing damage to a system if it spawns in a room with a system in it, and potentially dealing hull damage at the same time if the system is destroyed. While Shields are said to reduce the effect, even max shields don't entirely negate it.
See Red Giant Events.
The nebula here will make fleet pursuit slower but will disrupt your sensors.
Nebula disrupt use of the Sensors sub-system. The Slugs' telepathic abilities give them an advantage here. Some sectors are completely covered with nebula, in other sectors a section of the beacons on the FTL map may be covered by nebula. Whether or not the AI of the game is impeded by missing sensors is unknown as they attack random areas inside and outside nebulae. The speed with which the rebels chase you is reduced while inside a nebula - by 50% outside of nebula sectors and by 30% inside nebula sectors.
Nebulas do not count as environmental hazards for the purpose of the Tactical Approach achievement.
See Nebula Events.
This section of the nebula is experiencing an ion storm.
Inside large clouds, nebula hazards also have a chance of being paired with a plasma or an ion storm, which makes your reactor run at half-efficiency (rounded up). In these, it is best to shut off all non-essential systems (such as the medbay - just keep in mind that depowered clone bay does not work without the backup DNA bank augmentation) so that there is enough power for the weapons/drones if you intend to fight, or for the engines and shields if you intend to run or leave if the beacon is empty.
Oxygen may be automatically depowered in a plasma storm so upon exit be sure to power it up. Typically your crew can survive a moderate-length battle without active o2, letting you to free up that one critical bit of energy, but watch out if the battle draws longer or if your enemy has a realistic chance of further harming your life support!
Notably, enemy ships' reactors are also halved, which can make the battle easier. However, like you, they can re-allocate power when systems are damaged or destroyed, potentially doubling their shields or deploying a new weapon mid-battle. This tends to make plasma storm fights a strategic headache.
The battery backup subsystem and the power from Zoltan crew members are unaffected by plasma storms, making them very useful in nebula zones.
Rebel controlled nebula beacons will always have an ion storm, regardless of if there was one earlier or not. The exception is the exit beacon if it is in a nebula.
Ion Storms will instantly drain player weapon charges on arrival, rather than let them fall over time. (No longer in Advanced Edition)
See Plasma Storm Events.
Asteroid field detected in this location.
Asteroids will periodically fly towards your ship. They will either knock down a single shield layer or deal 1 point of hull/system damage to a random room on the ship. Like some Lasers, they have a small chance to cause a fire or a breach. They have the same effect on the enemy ship, should you be fighting one.
The interval between each asteroid is random. In the worse case scenario - a ship with only 1 shield and either an unmanned or inexperienced crew member manning shields - if the ship is hit by 1 asteroid, it is possible to be hit by another before the shields regenerate. Thus, having at least 2 layers of shields is very valuable within an asteroid field. Additionally, Defense drones are very effective against incoming asteroids, rendering the ship nearly invulnerable to this hazard. A Hacking system can come in handy here to disable enemy shields and make them take damage from asteroids.
Asteroid fields are a great place to level up your crew in shields and evasion. This experience can only be gained during battle, even though asteroids will continue flying by or impacting your shields afterwards.
A pulsar is flooding this area with dangerous electromagnetic forces.
You can encounter a pulsar only if you play with Advanced Edition content on.
The game will warn you of an ion pulse before a pulse from the star, just like the solar flare from the Red giant or the target lock on the Planet-side battery. The pulse causes 5 ion damage on one system, shields first if they are up, and 4 ion damage to another random system even if they are. The only way to protect yourself from the effect is a Reverse Ion Field. If the shields are down, all ion damage will be done to a second random system instead. Hitting pulsating star beacons early-game can be deadly, as your shields are still very low, thus it is best to finish battles as quickly as possible here. If you are fighting an enemy ship, they will also be affected. The star will continue to pulse even after combat, and the only so it is suggested you leave right before another pulse hits. Ion damage will carry over to the next beacon, so be cautious where you jump.[Warning:this can be very dangerous if you jump to an asteroid field]!
Since it is ion damage, sporting a Zoltan Shield - which takes double ion damage - is particularly ineffective, and it will be taken out in two hits; another good reason to stay away from pulsars when using a Zoltan ship layout.
Some drones are particularly useful at this hazard. Attack drones can often deal enormous damage once enemy shields are down, and an anti-drone unit provides valuable insurance. The Shield Overcharger is surprisingly useful. Even one bar of supershield will absorb an entire star pulse, protecting your shields and systems.
Anti-Ship Battery (ASB)Edit
Planet-side anti-ship batteries are detected in this system.
PLEASE NOTE: The ASB is not considered an Environmental Hazard for the Stealth Cruiser achievement Tactical Approach.
Planet-Side Batteries periodically fire a shield-piercing 3-damage shot, hits a random room, and always causes a hull breach. These shots can sometimes miss. The miss chance for each shot follows the same rules as other enemy incoming shots. For example, if your evade chance is 30 percent, a shot from an ASB will have a 30 percent chance to miss your ship. This weapon also bypasses Zoltan shields; the Zoltan shield takes no damage, but the ship will take hull damage.
ASBs are fairly rare and often avoidable, but encountering them at any point in the game can be extremely dangerous. When you have few crew or inexperienced repairmen, it is easy to get bogged down with repairing the breaches and systems. The hull damage over time is not to be underestimated; 10 shots will take down a fully-repaired ship. Since the damage is unblockable, escaping from this hazard speedily should be your first priority.
It is notable that, although many shots will be animated firing at you during this hazard, the only one that connects is the shot that you are loudly forewarned about. This is probably on account of the battery's inability to effectively target you, seeing as it is supposed to be located far below you on the orbiting planet's surface. When an ASB locks onto your ship, you will be notified with a warning message and a loud siren.
Planet-side Batteries are present in Rebel Controlled sectors, making them even more deadly.
If you get overtaken by the Rebel Fleet or jump in a rebel controlled beacon, ASB shots will be coming from one of closest rebel ships, but game will still say that ASB is on planet. ASB will fire always in rebel controlled beacons, with a few exceptions. Exceptions include if you are at a nebula beacon, or at the exit beacon while playing on easy mode.
Friendly ASBs can be found taking down enemy ships during rare events, mostly in Abandoned Sector.