SpaceX plans to launch a pair of long-delayed navigation satellites this evening at 8:34PM from Pad 39A at Kennedy Space Center.  Should conditions force a scrub, the next backup opportunity is on Sunday, April 28 at 8:30 PM EDT.

The satellites, FM25 and FM27, are being launched aboard a Falcon 9 booster as part of Europe’s MEO Galileo constellation. They will join twenty-six other satellites that began launching in 2011 to form part of a high-precision navigation system for the European Union. 

Payload: A European Navigation System Similar to GPS

Similar to the United States’ GPS, and the Russian GLONASS system, the EU intends to reduce Europe’s reliance on those systems. Either can be degraded at any time by their respective countries, which in turn could make the systems unsuitable for aviation or military purposes. 

 Like the other systems, Galileo will offer two levels of service: one for general navigation use by the public, which will be free, and a high-precision system which will operate on a subscription basis. The high precision tier will allow location pinpointing both horizontally and vertically within 1 meter or better. 

Among the final few satellites of the $10 billion Galileo project, FM 25 and 27 were originally contracted to launch on Russian Soyuz rockets. That plan was scrapped in recent years due to geopolitical considerations, and the satellites were then shifted to the ESA’s Ariane 6. That new ESA rocket has experienced delays, leading to another shift, and Europe has now contracted with Space X for the launches.   

Weather

The US Space Force’s 45th Weather Squadron forecasts a 25% Probability of Violation of acceptable range weather conditions, meaning they expect a 75% chance of weather being acceptable for liftoff during the launch window.

Chance For a Jellyfish Phenomona?

Since this evening’s launch is at 8:34PM EDT, there is a chance of a bright “jellyfish” appearing in the sky after staging. “Jellyfish” is the unofficial nickname for when the sun is below the horizon at ground level, but is still visible in the upper atmosphere: that lights the gaseous plume of the rocket’s exhaust brightly, and looks somewhat similar to marine animal common to the coast.

April 27 Sunset

• Sunset: 7:54 PM EDT
• Civil Twilight Ends: 8:19 PM EDT
• Planned Launch Time: 8:34 PM EDT
• Nautical Twilight Ends: 8:48 PM EDT

That’s the right time for a jellyfish to make an appearance. Even then, to see this, skies need to be clear between the viewer and the rocket high in the sky. The National Weather Service is predicting around 30% of the sky will be covered by clouds around launch time.

Trajectory

Landing

None.

In order to achieve the desired Medium-Earth orbit, tonight’s mission requires an expendable booster. As such, SpaceX will not make any landing attempt. After stage separation, the booster will fall into the ocean, much like other traditional launces (Atlas V, SLS, Delta IV Heavy.)

Booster: B1060

Tonight, we’ll bid farewell to one of SpaceX’s most experienced boosters, B1060. It has completed twenty previous missions, including GPS III-3, Turksat 5A, Transporter-2, Intelsat G-33/G-34, Transporter-6, Intuitive Machines IM-1, and 13 Starlink missions.

Booster B-1060
Flight Number	Payload	Date
1	GPS III SV03	June 30, 2020
2	Starlink L11	September 3, 2020
3	Starlink L14	October 24, 2020
4	Türksat 5A	January 8, 2021
5	Starlink L18	February 4. 2021
6	Starlink L22	March 24, 2021
7	Starlink L24	April 29, 2021
8	Transporter-2	June 20, 2021
9	Starlink 4-3	December 2, 2021
10	Starlink 4-6	January 19, 2022
11	Starlink 4-9	March 3, 2022
12	Starlink 4-14	April 21. 2022
13	Starlink 4-19	June 17, 2022
14	Galaxy 34 / 35	October 8, 2022
15	Transporter-6	January 3. 2023
16	Starlink 5-15	July 16, 2023
17	Starlink 6-18	September 24, 2024
18	IM-1 Odysseus Lander	February 15, 2024
19	Starlink 6-42	March 23, 2024

Online Viewing

A live webcast of this mission will begin on SpaceX’s X account feed about five minutes prior to liftoff. 
Watch live on X.

SpaceX’s official web page has links to their live coverage as well as up-to-date planned launch times. Galileo L12 Mission Page

Spaceflight Now will begin its live launch feed one hour prior to liftoff.
SFN on Youtube.

In-Person Launch Viewing

Today’s launch is from LC-39A at Kennedy Space Center, which means that the best direct views of liftoff are at either the Max Brewer Bridge in Titusville, or the northern parks on US-1 in Titusville: Space View Park, Rotary Riverfront Park and Parrish Park are excellent choices. Arrive early for the best parking.

Playalinda Beach at the Cape Canaveral National Seashore closes at 8 PM EDT, as does Merritt Island National Wildlife Refuge. This location is not an option for the launch tonight.

The ascending rocket will also be visible on Cocoa Beach, Cocoa Beach Pier, Jetty Park Pier after liftoff when Falcon 9 clears any obstructions.

The ascending rocket will also be visible on the beaches after liftoff when Falcon 9 clears any obstructions.

As always, a launch can be delayed at any time. Pack patience and maybe a wind-breaker in case there is a shower.

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_{Note: article contains shared content by Mark Stone at Florida Media Now and is used by permission of the author.}