Launches · Falcon 9 · Vandenberg, California

Iridium-4: who could see the launch

Launched · Friday, December 22, 2017 at 5:27 PM PST

SpaceX's Falcon 9 launched Iridium-4 from Vandenberg, California at 5:27 PM PST on Friday, December 22, 2017.

It flew south, down the Pacific coast, into an orbit over the poles.

It went up 31 minutes after sunset at the pad. The exhaust high up was still in sunlight while the ground was dark, so it could glow as a "jellyfish" plume from 44 of the cities below.

Best views: Los Angeles, San Diego, Tijuana and 19 more.

Low on the horizon from Phoenix, San Jose, San Francisco and 19 more.

Can I see it from my city? 65 cities within 1,500 km

City	Distance	Look toward	Highest	When	View
Lompoc, California	14 km (9 mi)	up, toward the pad, then south	50°	5:27–5:35 PM PST	Good view jellyfish possible	14 km (9 mi) · look up, toward the pad, then south · up to 50° · 5:27–5:35 PM PST
Santa Maria, California	39 km (24 mi)	southwest	32°	5:28–5:35 PM PST	Good view jellyfish possible	39 km (24 mi) · look southwest · up to 32° · 5:28–5:35 PM PST
Oxnard, California	140 km (87 mi)	west, moving south	33°	5:28–5:35 PM PST	Good view jellyfish possible	140 km (87 mi) · look west, moving south · up to 33° · 5:28–5:35 PM PST
Bakersfield, California	167 km (104 mi)	southwest, moving south	21°	5:28–5:35 PM PST	Good view jellyfish possible	167 km (104 mi) · look southwest, moving south · up to 21° · 5:28–5:35 PM PST
Thousand Oaks, California	171 km (106 mi)	west, moving south	29°	5:28–5:35 PM PST	Good view jellyfish possible	171 km (106 mi) · look west, moving south · up to 29° · 5:28–5:35 PM PST
Santa Clarita, California	191 km (119 mi)	west, moving south	24°	5:28–5:35 PM PST	Good view jellyfish possible	191 km (119 mi) · look west, moving south · up to 24° · 5:28–5:35 PM PST
Visalia, California	223 km (139 mi)	southwest	15°	5:29–5:35 PM PST	Good view jellyfish possible	223 km (139 mi) · look southwest · up to 15° · 5:29–5:35 PM PST
Lancaster, California	226 km (140 mi)	west, moving south	20°	5:28–5:35 PM PST	Good view jellyfish possible	226 km (140 mi) · look west, moving south · up to 20° · 5:28–5:35 PM PST
Los Angeles, California	227 km (141 mi)	west, moving south	24°	5:28–5:35 PM PST	Good view jellyfish possible	227 km (141 mi) · look west, moving south · up to 24° · 5:28–5:35 PM PST
Long Beach, California	243 km (151 mi)	west, moving south	26°	5:29–5:36 PM PST	Good view jellyfish possible	243 km (151 mi) · look west, moving south · up to 26° · 5:29–5:36 PM PST
Salinas, California	246 km (153 mi)	south	14°	5:29–5:35 PM PST	Low on the horizon jellyfish possible	246 km (153 mi) · look south · up to 14° · 5:29–5:35 PM PST
Fresno, California	247 km (153 mi)	south	14°	5:29–5:35 PM PST	Low on the horizon jellyfish possible	247 km (153 mi) · look south · up to 14° · 5:29–5:35 PM PST
West Covina, California	253 km (157 mi)	west, moving south	23°	5:29–5:35 PM PST	Good view jellyfish possible	253 km (157 mi) · look west, moving south · up to 23° · 5:29–5:35 PM PST
Anaheim, California	263 km (163 mi)	west, moving south	24°	5:29–5:36 PM PST	Good view jellyfish possible	263 km (163 mi) · look west, moving south · up to 24° · 5:29–5:36 PM PST
Irvine, California	278 km (173 mi)	west, moving south	24°	5:29–5:36 PM PST	Good view jellyfish possible	278 km (173 mi) · look west, moving south · up to 24° · 5:29–5:36 PM PST
Rancho Cucamonga, California	283 km (176 mi)	west, moving south	21°	5:29–5:35 PM PST	Good view jellyfish possible	283 km (176 mi) · look west, moving south · up to 21° · 5:29–5:35 PM PST
Victorville, California	304 km (189 mi)	west, moving south	18°	5:29–5:35 PM PST	Good view jellyfish possible	304 km (189 mi) · look west, moving south · up to 18° · 5:29–5:35 PM PST
Riverside, California	305 km (190 mi)	west, moving south	20°	5:29–5:35 PM PST	Good view jellyfish possible	305 km (190 mi) · look west, moving south · up to 20° · 5:29–5:35 PM PST
San Jose, California	322 km (200 mi)	south	11°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	322 km (200 mi) · look south · up to 11° · 5:29–5:34 PM PST
Modesto, California	336 km (209 mi)	south	11°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	336 km (209 mi) · look south · up to 11° · 5:29–5:34 PM PST
Oceanside, California	338 km (210 mi)	northwest, moving south	22°	5:29–5:36 PM PST	Good view jellyfish possible	338 km (210 mi) · look northwest, moving south · up to 22° · 5:29–5:36 PM PST
Temecula, California	343 km (213 mi)	west, moving south	20°	5:29–5:36 PM PST	Good view jellyfish possible	343 km (213 mi) · look west, moving south · up to 20° · 5:29–5:36 PM PST
Fremont, California	347 km (216 mi)	south	11°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	347 km (216 mi) · look south · up to 11° · 5:29–5:34 PM PST
San Mateo, California	360 km (224 mi)	southeast	10°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	360 km (224 mi) · look southeast · up to 10° · 5:29–5:34 PM PST
Escondido, California	366 km (227 mi)	northwest, moving south	21°	5:29–5:36 PM PST	Good view jellyfish possible	366 km (227 mi) · look northwest, moving south · up to 21° · 5:29–5:36 PM PST
Stockton, California	375 km (233 mi)	south	10°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	375 km (233 mi) · look south · up to 10° · 5:29–5:34 PM PST
San Diego, California	384 km (239 mi)	northwest, moving south	22°	5:29–5:36 PM PST	Good view jellyfish possible	384 km (239 mi) · look northwest, moving south · up to 22° · 5:29–5:36 PM PST
San Francisco, California	385 km (239 mi)	southeast	10°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	385 km (239 mi) · look southeast · up to 10° · 5:29–5:34 PM PST
Concord, California	393 km (244 mi)	south	9°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	393 km (244 mi) · look south · up to 9° · 5:29–5:34 PM PST
El Cajon, California	394 km (245 mi)	northwest, moving south	21°	5:29–5:36 PM PST	Good view jellyfish possible	394 km (245 mi) · look northwest, moving south · up to 21° · 5:29–5:36 PM PST
Tijuana, MX	410 km (255 mi)	northwest, moving south	22°	5:29–5:36 PM PST	Good view jellyfish possible	410 km (255 mi) · look northwest, moving south · up to 22° · 5:29–5:36 PM PST
Vallejo, California	413 km (257 mi)	south	9°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	413 km (257 mi) · look south · up to 9° · 5:29–5:34 PM PST
Fairfield, California	422 km (262 mi)	south	9°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	422 km (262 mi) · look south · up to 9° · 5:29–5:34 PM PST
Elk Grove, California	425 km (264 mi)	south	9°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	425 km (264 mi) · look south · up to 9° · 5:29–5:34 PM PST
Sacramento, California	446 km (277 mi)	south	8°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	446 km (277 mi) · look south · up to 8° · 5:29–5:34 PM PST
Roseville, California	462 km (287 mi)	south	8°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	462 km (287 mi) · look south · up to 8° · 5:29–5:34 PM PST
Santa Rosa, California	463 km (288 mi)	south	8°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	463 km (288 mi) · look south · up to 8° · 5:29–5:34 PM PST
Las Vegas, Nevada	524 km (326 mi)	southwest	9°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	524 km (326 mi) · look southwest · up to 9° · 5:29–5:34 PM PST
Henderson, Nevada	534 km (332 mi)	west, moving southwest	9°	5:29–5:34 PM PST	Low on the horizon jellyfish possible	534 km (332 mi) · look west, moving southwest · up to 9° · 5:29–5:34 PM PST
Reno, Nevada	549 km (341 mi)	south	6°	5:30–5:33 PM PST	Low on the horizon jellyfish possible	549 km (341 mi) · look south · up to 6° · 5:30–5:33 PM PST
Peoria, Arizona	780 km (485 mi)	west, moving southwest	7°	6:30–6:35 PM MST	Low on the horizon jellyfish possible	780 km (485 mi) · look west, moving southwest · up to 7° · 6:30–6:35 PM MST
Phoenix, Arizona	798 km (496 mi)	west, moving southwest	7°	6:30–6:35 PM MST	Low on the horizon jellyfish possible	798 km (496 mi) · look west, moving southwest · up to 7° · 6:30–6:35 PM MST
Mesa, Arizona	821 km (510 mi)	west, moving southwest	7°	6:30–6:35 PM MST	Low on the horizon jellyfish possible	821 km (510 mi) · look west, moving southwest · up to 7° · 6:30–6:35 PM MST
Tucson, Arizona	934 km (580 mi)	west, moving southwest	6°	6:31–6:35 PM MST	Low on the horizon jellyfish possible	934 km (580 mi) · look west, moving southwest · up to 6° · 6:31–6:35 PM MST

21 cities where it stays below the horizon

Provo, Salt Lake City, Boise, Eugene, Salem, Portland, Hillsboro, Albuquerque, Las Cruces, El Paso, Juárez, Tacoma, Kent, Seattle, Spokane, Colorado Springs, Boulder, Pueblo, Everett, Denver, Centennial

From where you are

Not near one of these cities? or pick a place:

The launch

Liftoff: Dec 22, 2017, 5:27 PM PST
Status: Launched
Rocket: Falcon 9 (SpaceX)
Mission: Iridium-4
Pad: Space Launch Complex 4E, Vandenberg SFB, CA, USA

Minute by minute

A rocket at night looks like a bright, steady light climbing slowly, often with a glowing trail. After two or three minutes it gets smaller as it heads downrange, and you may see the first stage drop away.

Why the "jellyfish"? Around sunset and sunrise the ground is in shadow, but sunlight still reaches the exhaust high up. It glows and spreads into a huge, slowly growing cloud. People report it as a UFO almost every time.

Did you see it?

These reports came in around liftoff, and our sky checks matched them to this launch.

Rocket, not Roswell

Glowing plume over Los Angeles after sunset: the Iridium-4 Falcon 9

Los Angeles, California, US · Dec 22, 2017, 5:35 PM PST · 100% match

From the archive 0 replies · 0 witnesses

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How we work this out: we follow a typical climb to orbit (about 70 km up two and a half minutes after liftoff, and about 210 km up and 1,400 km downrange after eight) in the direction the rocket flies, then work out how high above each city's horizon it gets and how dark that city's sky is. Clouds, hills and city lights aren't included. Launch times come from Launch Library 2 by The Space Devs. More on our methods.