A twilight phenomenon is produced when exhaust particles from missile or rocket propellant left in the vapor trail of a launch vehicle condense, freeze, and then expand in the less dense upper atmosphere. The exhaust plume, which is suspended against a dark sky, is then illuminated by reflective high-altitude sunlight through dispersion, which produces a spectacular, colorful effect when seen at ground level.
A twilight phenomenon (seen from the Louisiana-24 Long Range Tracking Telescope site in northern Santa Barbara county) lights up the night sky over Vandenberg Air Force Base following the launch of a Minuteman III missile September 19, 2002 (Official USAF Photo by Dennis Fisher, 30th Communications Squadron)
The twilight phenomenon caused by freezing unspent fuel from a Minotaur I launch at Vandenberg AFB, CA in Sept. 2005
The phenomenon typically occurs with launches that take place either 30 to 60 minutes before sunrise or after sunset when a booster rocket or missile rises out of the darkness and into a sunlit area, relative to an observer's perspective on the ground. Because rocket trails extend high into the stratosphere and mesosphere, they catch high-altitude sunlight long after the sun has set on the ground. The small particles in the expanding exhaust plume or "cloud" diffract sunlight and produce the rose, blue, green and orange colors—much like a dispersive prism can be used to break light up into its constituent spectralcolors (the colors of the rainbow) – thereby making the twilight phenomenon all the more spectacular.[1]
The exhaust plume may also take on a corkscrew appearance as it is whipped around by upper-level wind currents. It is typically seen within two to three minutes after a launch has occurred. Depending on weather conditions, it could remain in the sky for up to half an hour before dispersing.
At Vandenberg AFB in California, more than 1,800 missiles and space boosters have been launched from the central California coastline in northern Santa Barbara County since December 1958. However, only a small percentage of these launches have created the twilight phenomenon. The same is true with the U.S. Navy's Strategic Systems Programs, which conducts Trident II (D5) missile test flights at sea from Ohio Class SSBNsubmarines in the Pacific Test Range off the coast of Southern California, or Kokola Point at Barking Sands on the Hawaiian island of Kauai.
Some observers have wrongly assumed the missile or rocket creating the aerial spectacle must have malfunctioned or been destroyed while in flight. That belief stems from the appearance of the launch vehicle's contrail as it becomes twisted into knots by upper altitude air currents or wind shear. To date, no malfunctioning missile or rocket has been known to create the phenomenon. On the rare occasions when a missile or rocket does malfunction, it is destroyed by a Range Safety Officer before reaching the altitudes where twilight phenomenon occur.
The phenomenon's appearance and intensity varies with viewer location and weather conditions—typically, clear skies with no moonlight, since cloud cover would block one's view. The phenomenon can usually be seen throughout the state of California, and as far away as Arizona, Nevada and Utah. On the East Coast, similar sightings were observed and reported during twilight launches of the Space Shuttle from NASA's Kennedy Space Center, and observed after other expendable launch vehicles from the U.S. Space Force's launch complexes at Cape Canaveral Space Force Station in Florida.
Infographic showing in conditions required for the phenomena to occur.
In 2010 a contrail from an airplane in California had people believing they saw a missile launch.[2]
On July 7, 2010, reports of a "UFO" sighting forced Xiaoshan Airport in Hangzhou, China to temporarily cease operations.[3] The event appears to have been sparked by a flight crew preparing for descent and detected the object—suspected to be a Chinese rocket test—as a bright twinkling light ‘above’ the runway and notified the air traffic control department. ATC could not locate it on radar and prudently waved off landing flights. Eighteen flights were affected. Though normal operations resumed four hours later, the incident captured the attention of the Chinese media and sparked a firestorm of speculation on the UFO's identity.
On Nov. 7, 2015 a bright plume of light was seen expanding then "exploding" over south California between 7-8pm. The Orange County Sheriff confirmed this was in fact a Trident II ballistic missile test firing from the USS Kentucky.[4]
On Dec. 22, 2017 a bright plume from a Falcon 9 rocket launching the Iridium NEXT 31-40 satellites from Vandenberg Air Force Base was observed. The launch occurred during sunset which caused "jaw-dropping views" of the ascent to space.
On Oct. 7, 2018 this phenomenon was captured spectacularly over downtown Los Angeles in a timelapse[5] as the Falcon 9 rocket launched from nearby Vandenberg Air Force Base. The rocket launched at 7:21pm local time, 43 minutes after sunset.
^McKee, Maggie (2010-11-09). "Mystery 'missile' likely a jet contrail, says expert". New Scientist. from the original on 2010-11-10. Retrieved 2010-11-10.
^. National Ledger. July 10, 2010. Archived from the original on July 13, 2010. Retrieved July 11, 2010.
^"Mystery Light in Southern California Sky Sparks Anxiety - CNN.com". CNN. 8 November 2015. Retrieved 2015-11-08.
^"SpaceX Falcon 9 launch timelapse over downtown Los Angeles". Twitter. Retrieved 2020-08-15.
Video
RUS Progress MS-10 launch, as seen from the International Space Station over Baikonur, Kazakhstan Taken by ESA astronaut Alexander Gerst, Nov. 16, 2018
SpaceX Iridium 4 launch, as seen from Alhambra, Calif. Misrraim Sanchez YouTube video, Dec. 22, 2017
Iridium NEXT IV launch, as seen from Manhattan Beach, Calif. Scott Gauer YouTube video, Dec. 22, 2017
Justin Majeczky's 40-second time lapse of U.S. Navy Trident II (D5) missile test, as seen from San Francisco Vimeo, Nov. 8, 2015
Missile launch over San Francisco YouTube video, Nov. 8, 2015
Atlas V Rocket Launch view from East Orlando, Florida YouTube video Sept 2, 2015
Night Time Launch Of Russian Space Rocket Heading To ISS YouTube video Feb. 15, 2014
Video of "UFO" over Xiaoshan Airport in Hangzhou, China YouTube video July 7, 2010
External links
A photographer shot an awesome time-lapse of SpaceX’s recent rocket launch from Yuma, Arizona The Verge, Dec. 26, 2017
Dashcam video shows three-car crash as freeway drivers brake for SpaceX rocket launch Los Angeles Times, Dec. 26, 2017
What was that light in the sky? SpaceX Falcon 9 launch offers dramatic show over L.A. Los Angeles Times, Dec. 22, 2017
Light from Navy test fire courses across the Southern California and Arizona sky Los Angeles Times, Nov. 8, 2015 (The same missile launch as seen over San Francisco)
Mystery light above L.A. brings fear, anger and questions Los Angeles Times, Nov. 8, 2015
UFO scares are the price we pay for secret missile tests, expert says Los Angeles Times, Nov. 8, 2015
Mystery light streaking across Bay Area skies was a test missile SF Gate, Nov. 8, 2015
No UFO Here! Mysterious Flying Object Seen in Southern California Was Just a Missile Test People Magazine Online, Nov. 8, 2015
Everybody lost it when a Navy missile lit up the night sky over the West Coast Business Insider, Nov. 7, 2015
Rocket Trails at Twilight Illuminate the Sky
Rocket Twilight Phenomenon
2020 Hindsight: Whee! Ooh! Aah! Pretty!
Rocket puts on "Streak" show Santa Maria Times, Sept. 23, 2005
National Defense Light Show Treebeard's Stumper Answer, Sept. 27, 2002
Minuteman-II launch from Vandenberg AFB Goleta Air & Space Museum, July 14, 2001
Rocket Launches Fred Bruenjes' Astronomy Stuff, June 7, 2007
Space Archive
SoCal SkyLights
January 13, 2023
twilight, phenomenon, twilight, phenomenon, produced, when, exhaust, particles, from, missile, rocket, propellant, left, vapor, trail, launch, vehicle, condense, freeze, then, expand, less, dense, upper, atmosphere, exhaust, plume, which, suspended, against, d. A twilight phenomenon is produced when exhaust particles from missile or rocket propellant left in the vapor trail of a launch vehicle condense freeze and then expand in the less dense upper atmosphere The exhaust plume which is suspended against a dark sky is then illuminated by reflective high altitude sunlight through dispersion which produces a spectacular colorful effect when seen at ground level A twilight phenomenon seen from the Louisiana 24 Long Range Tracking Telescope site in northern Santa Barbara county lights up the night sky over Vandenberg Air Force Base following the launch of a Minuteman III missile September 19 2002 Official USAF Photo by Dennis Fisher 30th Communications Squadron The twilight phenomenon caused by freezing unspent fuel from a Minotaur I launch at Vandenberg AFB CA in Sept 2005 The phenomenon typically occurs with launches that take place either 30 to 60 minutes before sunrise or after sunset when a booster rocket or missile rises out of the darkness and into a sunlit area relative to an observer s perspective on the ground Because rocket trails extend high into the stratosphere and mesosphere they catch high altitude sunlight long after the sun has set on the ground The small particles in the expanding exhaust plume or cloud diffract sunlight and produce the rose blue green and orange colors much like a dispersive prism can be used to break light up into its constituent spectral colors the colors of the rainbow thereby making the twilight phenomenon all the more spectacular 1 The exhaust plume may also take on a corkscrew appearance as it is whipped around by upper level wind currents It is typically seen within two to three minutes after a launch has occurred Depending on weather conditions it could remain in the sky for up to half an hour before dispersing At Vandenberg AFB in California more than 1 800 missiles and space boosters have been launched from the central California coastline in northern Santa Barbara County since December 1958 However only a small percentage of these launches have created the twilight phenomenon The same is true with the U S Navy s Strategic Systems Programs which conducts Trident II D5 missile test flights at sea from Ohio Class SSBN submarines in the Pacific Test Range off the coast of Southern California or Kokola Point at Barking Sands on the Hawaiian island of Kauai Some observers have wrongly assumed the missile or rocket creating the aerial spectacle must have malfunctioned or been destroyed while in flight That belief stems from the appearance of the launch vehicle s contrail as it becomes twisted into knots by upper altitude air currents or wind shear To date no malfunctioning missile or rocket has been known to create the phenomenon On the rare occasions when a missile or rocket does malfunction it is destroyed by a Range Safety Officer before reaching the altitudes where twilight phenomenon occur The phenomenon s appearance and intensity varies with viewer location and weather conditions typically clear skies with no moonlight since cloud cover would block one s view The phenomenon can usually be seen throughout the state of California and as far away as Arizona Nevada and Utah On the East Coast similar sightings were observed and reported during twilight launches of the Space Shuttle from NASA s Kennedy Space Center and observed after other expendable launch vehicles from the U S Space Force s launch complexes at Cape Canaveral Space Force Station in Florida Numerous nations with a space program such as the European Space Agency the Russian Space Agency the China National Space Agency Japan s JAXA India s ISRO and other countries have experienced the same event Contents 1 Examples 2 See also 3 References 4 Video 5 External linksExamples Edit Infographic showing in conditions required for the phenomena to occur In 2010 a contrail from an airplane in California had people believing they saw a missile launch 2 On July 7 2010 reports of a UFO sighting forced Xiaoshan Airport in Hangzhou China to temporarily cease operations 3 The event appears to have been sparked by a flight crew preparing for descent and detected the object suspected to be a Chinese rocket test as a bright twinkling light above the runway and notified the air traffic control department ATC could not locate it on radar and prudently waved off landing flights Eighteen flights were affected Though normal operations resumed four hours later the incident captured the attention of the Chinese media and sparked a firestorm of speculation on the UFO s identity On Nov 7 2015 a bright plume of light was seen expanding then exploding over south California between 7 8pm The Orange County Sheriff confirmed this was in fact a Trident II ballistic missile test firing from the USS Kentucky 4 On Sept 2 2015 a bright plume from an Atlas V rocket launching the MUOS satellite from Cape Canaveral Air Force Station was seen by observers in Florida On Dec 22 2017 a bright plume from a Falcon 9 rocket launching the Iridium NEXT 31 40 satellites from Vandenberg Air Force Base was observed The launch occurred during sunset which caused jaw dropping views of the ascent to space On Oct 7 2018 this phenomenon was captured spectacularly over downtown Los Angeles in a timelapse 5 as the Falcon 9 rocket launched from nearby Vandenberg Air Force Base The rocket launched at 7 21pm local time 43 minutes after sunset See also EditNoctilucent clouds Space jellyfishReferences Edit Twilight phenomenon lights up sky McKee Maggie 2010 11 09 Mystery missile likely a jet contrail says expert New Scientist Archived from the original on 2010 11 10 Retrieved 2010 11 10 China Airport UFO Mystery or Military National Ledger July 10 2010 Archived from the original on July 13 2010 Retrieved July 11 2010 Mystery Light in Southern California Sky Sparks Anxiety CNN com CNN 8 November 2015 Retrieved 2015 11 08 SpaceX Falcon 9 launch timelapse over downtown Los Angeles Twitter Retrieved 2020 08 15 Video EditRUS Progress MS 10 launch as seen from the International Space Station over Baikonur Kazakhstan Taken by ESA astronaut Alexander Gerst Nov 16 2018 SpaceX Iridium 4 launch as seen from Alhambra Calif Misrraim Sanchez YouTube video Dec 22 2017 Iridium NEXT IV launch as seen from Manhattan Beach Calif Scott Gauer YouTube video Dec 22 2017 SpaceX Falcon 9 Launch Boostback Entry Burn Justin Foley s YouTube video Dec 22 2017 SpaceX launch video from Phoenix news helicopter Entire raw video as seen from PenguinAir Newschopper flying above Phoenix Arizona Dec 22 2017 Explaining The Amazing Rocket Trail Over LA Scott Manley s YouTube video Dec 24 2017 Falcon 9 rocket launch provides spectacular view in Bakersfield KBAK 29 Eyewitness News KBFX 58 Fox News BakersfieldNow com via YouTube Dec 22 2017 Justin Majeczky s 40 second time lapse of U S Navy Trident II D5 missile test as seen from San Francisco Vimeo Nov 8 2015 Missile launch over San Francisco YouTube video Nov 8 2015 Atlas V Rocket Launch view from East Orlando Florida YouTube video Sept 2 2015 Night Time Launch Of Russian Space Rocket Heading To ISS YouTube video Feb 15 2014 Video of UFO over Xiaoshan Airport in Hangzhou China YouTube video July 7 2010External links EditA photographer shot an awesome time lapse of SpaceX s recent rocket launch from Yuma Arizona The Verge Dec 26 2017 Dashcam video shows three car crash as freeway drivers brake for SpaceX rocket launch Los Angeles Times Dec 26 2017 What was that light in the sky SpaceX Falcon 9 launch offers dramatic show over L A Los Angeles Times Dec 22 2017 Light from Navy test fire courses across the Southern California and Arizona sky Los Angeles Times Nov 8 2015 The same missile launch as seen over San Francisco Mystery light above L A brings fear anger and questions Los Angeles Times Nov 8 2015 UFO scares are the price we pay for secret missile tests expert says Los Angeles Times Nov 8 2015 Mystery light streaking across Bay Area skies was a test missile SF Gate Nov 8 2015 No UFO Here Mysterious Flying Object Seen in Southern California Was Just a Missile Test People Magazine Online Nov 8 2015 Everybody lost it when a Navy missile lit up the night sky over the West Coast Business Insider Nov 7 2015 Rocket Trails at Twilight Illuminate the Sky Rocket Twilight Phenomenon 2020 Hindsight Whee Ooh Aah Pretty Rocket puts on Streak show Santa Maria Times Sept 23 2005 National Defense Light Show Treebeard s Stumper Answer Sept 27 2002 Minuteman II launch from Vandenberg AFB Goleta Air amp Space Museum July 14 2001 Rocket Launches Fred Bruenjes Astronomy Stuff June 7 2007 Space Archive SoCal SkyLights Retrieved from https en wikipedia org w index php title Twilight phenomenon amp oldid 1122349641, wikipedia, wiki, book, books, library,
