NROL-42 (SBIRS HEO-4) – Atlas V 541 (AV-072) – Ванденберг SLC-3E – 24.09.2017, 05:49 UTC

[tnt22]

http://www.vandenberg.af.mil/News/Article-Display/Article/1316901/atlas-v-launch-scheduled-from-vandenberg/

ATLAS V LAUNCH SCHEDULED FROM VANDENBERG
30th Space Wing Public Affairs / Published September 19, 2017


VANDENBERG AIR FORCE BASE, Calif. --
Team Vandenberg is scheduled to launch a United Launch Alliance Atlas V rocket carrying a National Reconnaissance Office payload from Space Launch Complex-3 on Thursday, Sept. 21, with a launch window opening at 10:38 p.m. PDT.

Col. Gregory Wood, 30th Space Wing vice commander, will be the launch decision authority.

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"This launch is the culmination of many months of work by United Launch Alliance, the National Reconnaissance Office and the 30th Space Wing," said Wood. "All of Team Vandenberg is dedicated to mission success and proud to play a part in delivering these capabilities to our nation."

The 4th Space Launch Squadron executes integrated launch operations with a focus on mission assurance for this launch operation.

"This launch is a prime example of teamwork by multiple organizations that have worked around the clock to assure mission safety and security," said Lt. Col. Kenneth Decker, 4th Space Launch Squadron commander. "Given the dedication of the men and women have worked to ensure readiness of the launch vehicle and payload, we're on track for a successful launch."

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[tnt22]

Прогноз погоды L-2

L-2 Launch Weather - 19 Sep 2017
 

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Updated: 09/20/2017 01:54 Weather is 60% GO

Weather forecasters, in their L-2 day outlook, predict a 60 percent chance of allowable conditions for the Atlas 5 rocket to launch Thursday night in California.

"A deep trough will move over the range on Thursday throughout the count, with the center of the trough passing over Space Launch Complex-3 by T-0. This lower pressure will begin to mix out the marine layer and cause stronger surface winds," Air Force meteorologists say.

"Throughout the count, the remnants of the marine layer will cause a slight reduction in visibility with patchy fog. Additionally, low stratus and stratocumulus will be present by T-0."

At launch time, the forecast calls for northwesterly winds of 12 to 15 knots with gusts to 20 knots and temperatures between 55 and 60 degrees F. Max upper level winds will be out of the west at 95 knots from 39,000 to 40,000 feet.

The main concerns are launch visibility and ground winds.

[tnt22]

NRO‏Подлинная учетная запись @NatReconOfc 35 мин. назад

#NROL42 is scheduled to launch from Space Launch Complex 3, VAFB, Ca., tomorrow. @ulalaunch

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[tnt22]

http://spaceflight101.com/atlas-v-nrol-42/atlas-v-nrol-42-launch-preview/

Electronic Eavesdropping Satellite Stands Ready for Liftoff atop Atlas V Rocket
September 20, 2017

A powerful Atlas V rocket sporting four boosters will light up the night over California late on Thursday, aiming for liftoff fr om Vandenberg Air Force Base at 5:38 UTC on Friday with the classified NROL-42 satellite for the U.S. National Reconnaissance Office, believed to be an eavesdropping and missile-tracking spacecraft working from a highly elliptical orbit in a system of orbiting listening posts operated by the U.S.

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Photo: United Launch Alliance

Thursday night's launch is the third NRO mission in 2017, following up on the launch of a pair of NOSS ship-tracking satellites in March and the mysterious NROL-76 that launched atop a SpaceX Falcon 9 in May and entered an uncharacteristic Low Earth Orbit, likely to test out new sensor technology. Two more NRO launches are on ULA's manifest for 2017 after this week's launch with the NROL-52 data relay satellite next on the company's Cape Canaveral manifest and NROL-47 – likely a radar surveillance satellite – targeting a mid-December blastoff from Vandenberg.

NROL-42 had been targeting a September 14 liftoff, but was pushed one week to allow United Launch Alliance employees to travel back to Florida to prepare for hurricane Irma that had threatened to impact Cape Canaveral as it made its way north along the Florida Peninsula. The decision to delay the launch was to allow employees to prepare their homes and evacuate their families.


NROL-42 Mission Patch – Credit: National Reconnaissance Office

Targeting a 10:38 p.m. local time liftoff, Atlas V will race off from Space Launch Complex 3E at Vandenberg under the power of its two-chamber RD-180 main engine and four Solid Rocket Boosters to deliver the initial kick needed to reach the classified orbital destination. Swinging to the south east, Atlas V will be flying on a coast-hugging trajectory for the initial portion of its mission, dropping the boosters just over a minute and a half into the flight. The protective payload fairing will be split from the climbing rocket three and a half minutes into the mission and the first stage will hand off to the Centaur upper stage just past the T+4-minute mark to finish the boost into orbit via a two-burn flight profile.

As is typical for classified NRO missions, live coverage of Thursday night's launch will end at the moment of fairing separation and no details on the satellite, its target orbit and intended mission will be released. The last to be heard of NROL-42 will be a confirmation of launch success after the satellite separates from the Atlas V booster, expected around an hour or hour and a half after launch based on previous missions.

What is hidden under Atlas V's five-meter payload fairing appears to be a high-fidelity electronic intelligence satellite flying under the code name Trumpet and tasked with vacuuming up vast amounts of communications and signals. Placed into a highly elliptical orbit peaking over the northern regions, the Trumpet satellites complement eavesdropping birds in Geostationary Orbit by providing improved coverage in the high-latitude regions wh ere viewing angles from GEO are not favorable.


NROL-35 blasts off from California – Photo: United Launch Alliance

The conclusion on NROL-42's identity is based on two major pieces of information – the type of launch vehicle in use for the mission and the target orbit that can be gleaned from navigational warnings issued for the launch.

Atlas V 541 – sporting four SRBs and a five-meter fairing – is the second most powerful Atlas V version currently in operation and was only used four times to date with NASA's Curiosity rover, the GOES-R weather satellite, NROL-67 and NROL-35. All of these, except NROL-35, occurred from Cape Canaveral, placing the NROL-42 satellite in the same group as NROL-35 launched back in December 2014.

NROL-35 had been suspected to be a new type of Trumpet signals intelligence spacecraft prior to its launch, a theory eventually confirmed by satellite observers finding the vehicle in a highly elliptical Molniya Orbit, inclined 63 degrees. Navigational warnings for NROL-42 closely match those of NROL-35, strongly suggesting the two missions are of similar type.

>> Identifying the classified NROL-42 Satellite


SBIRS HEO-4 Payload likely hosted by NROL-42 – Photo: Northrop Grumman

Another common element for the Trumpet HEO satellites is them acting as host spacecraft for the highly-elliptical orbit payloads of the Space-Based Infrared System (SBIRS) which uses stand-alone spacecraft in Geostationary Orbit and hosted payloads in Molniya orbits to detect and track missile launches across the globe. Responsible for the SBIRS HEO instrument, Northrop Grumman reported in June 2015 that the HEO-4 payload had been shipped for integration with its host – in-line with a two-year satellite assembly and testing schedule.

Satellite-based signals intelligence, along with image reconnaissance, build the most critical cornerstones in modern intelligence gathering. The U.S. in particular has a long history of in-space signals collection, starting out in the late 60s when the NRO launched its first series of communications intelligence craft known as Canyon, featuring ten-meter dishes to listen in on VHF and microwave communications from a near-Geostationary Orbit.

The desire for optimized and full collection over the Soviet Union, including its northern regions, prompted the inauguration of a second constellation segment, code named Jumpseat, with satellites in elliptical orbits to have at least one craft at high elevation over the regions of interest at any given time to characterize radar signals, capture microwave communications and record telemetry from missiles and re-entry vehicles.

At present, the NRO operates a number of Orion satellites drifting in Geostationary Orbit to collect communications and characterize all types of radio emitters on the ground. Other geostationary listening posts are flying under the Nemesis Program to capture entire satellite up-links, tasked by input from the NSA and CIA. Trumpet, as the primary collection post in Highly Elliptical Orbit, was inaugurated in the 1990s and transitioned into its first follow-on stage in 2006/08 and a second follow-on program whose code name is unknown started with NROL-35 in 2014.


Advanced Orion, redacted Image published by The Intercept

There have been reports that the Trumpet FO-2 satellites are substantially different than their predecessors in terms of technology but their overall mission architecture remains the same – complementing the Orion satellites in GEO by collecting a variety of signals intercepts over the northern hemisphere through a very large deployable antenna. The first Follow-On generation flew on the much smaller Atlas V 411 with only one booster and a four-meter fairing, suggesting the FO-2 satellites have significantly grown in mass.

Thursday night's launch will be the fifth for Atlas V in 2017 and the sixth for United Launch Alliance. The night's window duration is unknown.

Meteorologists have issued a 60% chance of favorable conditions with ground winds and launch visibility being the primary concerns as a deep trough moves over the range on Thursday and causes stronger surface winds when interacting with the marine layer.


NROL-42 Rollout – Photo: United Launch Alliance

Gearing up for a late night liftoff, Atlas V will enter countdown operations eight hours ahead of the opening of its launch window with initial vehicle power-up followed by a multi-hour checkout campaign to fully verify the electrical systems and communications link with the rocket. The Mobile Service Gantry will be rolled back five hours prior to T-0 to enable final pad close outs to occur before Atlas V heads into tanking after the countdown comes out of a planned hold at T-2 hours.

Already loaded with its dose of Rocket Propellant-1, Atlas V will receive -183°C Liquid Oxygen and -253°C Liquid Hydrogen over the course of a 90-minute tanking sequence. The RD-180-powered first stage will hold a total of 284 metric tons of Kerosene & LOX while the Centaur Upper stage will be filled with some 21 tonnes of cryogenics.

A final hold is scheduled at T-4 minutes to allow teams to catch up with any open items and assess the status of the launch vehicle, payload and western range as part of the final pre-launch poll. Ticking back from T-4 minutes, the highly choreographed countdown sequence will put Atlas V through the transition to internal power, the arming of the Flight Termination System, the pressurization of tanks and the handover of control to the vehicle's computers.

The Russian-built RD-180 engine will start breathing fire three seconds ahead of liftoff, putting out a whopping thrust of 392-metric ton force. Atlas V will catapult off its launch pad with a total thrust of 1,080-metric-ton-force when the four Solid Rocket Boosters fire up at the moment clocks reach zero.

Atlas V will enter its pitch and roll program six seconds after liftoff to align itself with its ascent path to the south east, flying along the Californian coast. Based on the performance of the 541 version, Atlas V will pass the speed of sound just 35 seconds after liftoff and encounter Maximum Dynamic Pressure 45 seconds into the flight.

>> Atlas V 541 Launch Vehicle


Expected Trumpet-FO-2-2 Ascent Path – Image: Google Earth / Spaceflight101

The four solid-fueled boosters will each consume 41 metric tons of propellant to generate 1,688kN of thrust over a burn of 94 seconds. As thrust tails off on the SRBs, Atlas V will be holding the 17-meter long boosters for another 15 seconds or so before jettisoning them in pairs.

Powered by the 4,152kN RD-180 engine alone, Atlas V will continue its flight toward space, burning 1,150 Kilograms of propellant each second. Approximately three and a half minutes into the flight, the protective payload fairing will be jettisoned, exposing the NROL-42 spacecraft. At this point, the mission will enter the pre-arranged news blackout to allow the classified satellite to reach its secret orbit without the public watching.

Per the typical flight design for the Atlas V, the Common Core Booster will conclude its role in the mission just after passing T+4 minutes – shutting down the RD-180 engine followed by the firing of separation pyros and ignition of small retrorockets to pull the 32.5-meter booster away from the Centaur upper stage. Centaur will then ignite its 101.8kN RL-10C engine for an initial burn aiming for a Parking Orbit followed by a coast phase and a second burn before releasing the satellite less than 50 minutes after launch.

Taking the NROL-35 launch as a basis, satellite analyst Ted Molczan expects NROL-42 to show up in an initial orbit of 2,100 by 37,750 Kilometers, inclined 62.85°. Navigational warnings issued for this mission indicate the Centaur upper stage will perform a deorbit maneuver after dispatching the satellite with re-entry expected in a small corridor south west of Tasmania around nine and a half to eleven hours after launch takes place.

Satellite trackers will swing into action after the NROL-42 payload reaches orbit, attempting to spot the newly launched satellite to provide final confirmation of the mission's identity.

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[tnt22]

Updated: 09/20/2017 20:30

LRR: The Launch Readiness Review today formally gave approval to proceed into countdown operations at Vandenberg Air Force Base in California to deploy the NROL-42 payload for the National Reconnaissance Office on Thursday using an Atlas 5 rocket.

Liftoff is targeted for 10:38 p.m. local time (that's Friday morning at 1:38 a.m. EDT; 0538 GMT).
...

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Atlas V NROL-42 Mission Profile

United Launch Alliance

Опубликовано: 20 сент. 2017 г.

(1:31)

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NRO‏Подлинная учетная запись @NatReconOfc 3 ч. назад

#NROL42 Mission Patch.

[tnt22]

NRO‏Подлинная учетная запись @NatReconOfc 3 ч. назад

#NROL42 Mission Patch depicts a grizzly bear in motion, representing the unceasing motion of a satellite along its orbital path.

[tnt22]

NRO‏Подлинная учетная запись @NatReconOfc 1 ч. назад

#NROL42 will carry a national security payload designed, built, and operated by @NatReconOfc

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Трансляция пуска

http://www.ulalaunch.com/atlas-v-to-launch-nrol42.aspx

Watch live! Coverage begins Sept. 21 at 10:18 p.m. PDT. Watch via the ULA website or YouTube channel.

--> 08:18 ДМВ 2017-09-22

[tnt22]

Прогноз погоды L-1

L-1 Launch Weather - 20 Sep 2017
 

[tnt22]

Updated: 09/21/2017 13:22

Countdown clocks will begin ticking this afternoon to ready an Atlas 5 rocket to haul a covert governmental asset into orbit from a California launch pad tonight.

The eight-hour launch countdown sequence will prepare the pad at Vandenberg Air Force Base and United Launch Alliance rocket for the NROL-42 flight.

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Liftoff is targeted for 10:38 p.m. local time (1:38 a.m. EDT; 0538 GMT).

The unclassified launch period extends to 11:35 o.m., but the actual usable launch window ends before that. The exact duration is secret.

It will be United Launch Alliance's 121st flight and the company's 25th for the National Reconnaissance Office.

"This launch is a prime example of teamwork by multiple organizations that have worked around the clock to assure mission safety and security," said Lt. Col. Kenneth Decker, 4th Space Launch Squadron commander at Vandenberg.

"Given the dedication of the men and women have worked to ensure readiness of the launch vehicle and payload, we're on track for a successful launch."

According to public warning notices, the rocket will head on a southeasterly track, traveling on the "coast-hugging" trajectory toward orbit to deploy its payload.

It is one of three courses typically followed from Vandenberg, ranging from coast-hugger to produce a 63-degree orbital tilt relative to the equator to sun-synchronous at 98 degrees to full retrograde at 121 degrees inclination.

"All of Team Vandenberg is dedicated to mission success and proud to
play a part in delivering these capabilities to our nation," said Col. Gregory Wood, 30th Space Wing vice commander and the launch decision authority.

Air Force meteorologists give 60 percent odds that the weather will allow the launch to occur. Patchy fog and gusty winds are the two concerns.

"A deep trough will move over the range on Thursday throughout the count, with the center of the trough passing over SLC-03 by T-0. This lower pressure will begin to mix out the marine layer and cause strong surface winds," the launch weather team reports.

"Throughout the count, the remnants of the marine layer will cause a slight reduction in visibility with patchy fog. Additionally, low stratus and stratocumulus will be present by T-0. Winds will be out of the northwest between 15 -- 18 knots with gusts to 25 knots at the surface. Temperatures will be between 55F and 60F at T-0."

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[Старый]

tnt22 пишет:
https://spaceflightnow.com/2017/09/19/ula-milestone-launch-for-national-reconnaissance-office-set-for-thursday/

ULA milestone launch for National Reconnaissance Office set for Thursday
 September 19, 2017 Justin Ray

 
 Patches of the 25 NRO missions, including this week's upcoming launch, that have been entrusted to ULA rockets. 

А где эмблема как сидят ВиниПух и его друзья и смотрят на полярную звезду? Нынешняя эмблема вызывает ассоциации с ней.

[tnt22]

http://spaceflight101.com/atlas-v-nrol-42/nrol-42-satellite/

Identifying the classified NROL-42 Satellite

NROL-42, in all likelihood, is the second Trumpet-Follow-On-2 satellite operated by the U.S. National Reconnaissance Office as part of its fleet of signals intelligence spacecraft tasked with vacuuming up vast amounts of satellite communications, intercepting telemetry signals fr om missiles and characterizing ground sites of interest based on radio activity.

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NROL-42 Mission Patch – Credit: National Reconnaissance Office

Trumpet satellites, also known as Advanced Jumpseat, operate in a highly elliptical orbit to complement satellites in Geostationary Orbit by providing improved coverage in the high-latitude regions, also carrying sensors for the detection of ballistic missile launches to patch up a blind spot of Geostationary missile monitoring satellites.

The United States National Reconnaissance Office is an intelligence agency tasked with the design, construction and operation of all U.S. reconnaissance satellites and delivers satellite intelligence to other three-letter intelligence agencies including signals intelligence for the NSA, image reconnaissance data to the NGA and measurement & signature intelligence to the DIA. Established in 1961, the NRO has been shrouded in great secrecy and its existence as an agency was only first acknowledged in the early 1990s.


Atlas V with NROL-35 (2014) – Photo: United Launch Alliance

As an intelligence agency, the NRO goes through great lengths to keep its activities secret, therefore the identity of all NRO satellites is classified. However, it is possible to identify the nature of satellites taking into account their launch site, launch window, launch vehicle type and ascent path. Sometimes, hints can be found in mission logos and, after launch, most satellites are typically tracked in orbit by a worldwide network of observers, revealing from wh ere they operate, and often what they are tasked with.

Some cases are easier to solve while other NRO missions can only be narrowed down to a number of candidates. NROL-42 is one of the easier cases to solve, starting with the Atlas V 541 launch vehicle that has so far flown only four missions – NASA's MSL Curiosity Rover, NROL-67, NROL-35 and GOES-R. All these launches with the exception of NROL-35 occurred from Cape Canaveral, putting NROL-42 in the same group as the NROL-35 satellite, being only the second 541 launch from Vandenberg.

NROL-35 was suspected before launching to be inaugurating a new type of Trumpet Signals Intelligence Craft. Hobbyist satellite trackers spotted the satellite in an orbit of 1,120 by 37,560 Kilometers, 63.5° – in-line with the previous generation of Trumpet satellites. Additional confirmation came through the U.S. Air Force that reported some time after the NROL-35 launch that the third HEO Payload of the Space-Based Infrared System (SBIRS) had successfully been launched on a host spacecraft operating in a Highly Elliptical Orbit (HEO).

NROL-42 uses the same launch vehicle configuration and launch site as NROL-35 and will follow a very similar launch path, leaving little doubt on its identity as the next Trumpet Signals Intelligence bird. Also, Northrop Grumman reported in June 2015 that the SBIRS HEO-4 payload had been shipped for integration with its host, in-line with a two-year satellite assembly & testing schedule leading up to launch.


Expected Trumpet-FO-2-2 Ascent Path – Image: Google Earth / Spaceflight101

Signals Intelligence, along with image reconnaissance, are the two major cornerstones in modern intelligence-gathering and, as satellites have taken over much of the world's secure and open communications, space-based intelligence collection has become a major focus among the large space-faring nations. The U.S. in particular has a long history of in-space signals collection, starting out in the late 60s when the NRO launched its first series of communications intelligence craft known as Canyon, featuring ten-meter dishes to listen in on radio communications from a near-Geostationary Orbit.

Six Canyon satellites reached orbit through 1977 and listened in on microwave and VHF communications, also providing a location of the signal source through triangulation from their non-stationary, but synchronous orbits. A complementary program active in Geostationary Orbit was Rhyolite (later re-named Aquacade) that launched four satellites in the 1970s, optimized to capture telemetry signals from Soviet and Chinese missiles and re-entry vehicles as well as microwave emissions from the Soviet Union.


Signals Intelligence Gathering in Action – USA-202 (Orion 6) Parked next to Thuraya 2 to intercept satellite phone conversations – Credit: Marco Langbroek, sattrackcam.blogspot.com

To provide full coverage of the Soviet Union, including its northern regions, satellites in Geostationary or near-GEO orbit were found to be insufficient due to extremely low elevation for the northern latitudes. This led to the inauguration of the Jumpseat program that deployed a constellation of satellites into highly elliptical Molniya orbits peaking over the northern hemisphere so that at least one satellite was actively listening over the northern regions at any given time, capturing radar signals and microwave communications.

Around half a dozen such satellites were launched from 1971 through the mid-80s (numbers differ among analysts due to similarities between Jumpseat and the Space Data System).

The Canyon satellites were followed by Program 'Vortex' in the late 70s through the 80s with five satellites being deployed to orbit, featuring larger, 38-meter diameter dishes. Later re-named Mercury, the original Vortex satellites were extremely long lived and continued supplying signals intelligence into the 2000s. Two Advanced Mercury satellites were launched into Geostationary Orbit in 1994 and 96 to continue supplying strategic-level communications intercepts and missile telemetry.


Advanced Orion, redacted Image published by The Intercept

The flagship Orion program was inaugurated in 1985 and to this day continues as the primary NRO intelligence-gathering system in Geostationary Orbit – going through its initial generation with two satellites deployed by the Space Shuttle in 1985 and '89, followed by a pair of Advanced Orion Satellites orbited by Titan-4 rockets in 1995 and 98 and a third generation starting in 2003 with three launches through 2010; Orion satellites launched in 2012 and 13 are likely belonging to a fourth generation.

The Orion satellites host very large (100-150-meter) antenna dishes to collect multiple signal types across a broad geographic area. Leaked documentation showed the satellites are sensitive enough to collect Wifi signals from networks some 36,000 Kilometers below them.

Additional Geostationary listening assets include the Nemesis Program with the mysterious PAN and CLIO satellites launched in 2009 and 2014 for direct tasking by the CIA and NSA, and the SHARP (SIGINT High Altitude Replenishment Program) for which there is one candidate satellite in orbit, potentially as an Orion follow-on.


SBIRS HEO-4 Payload likely hosted by NROL-42 – Photo: Northrop Grumman

Jumpseat, as the primary collection post in Highly Elliptical Orbit, transitioned to Trumpet in the 1990s with three satellites reaching orbit to build a fully functional constellation with each satellite providing around eight hours of coverage per day. A pair of Trumpet-Follow-On Satellites launched in 2006 and 2008 on Delta IV M+(4,2) and Atlas V 411 rockets, hosting the first two SBIRS HEO payloads to take on an additional role of monitoring missile activity in the northern regions to provide advance warnings of threats to U.S. and allied assets.

A follow-on to the Trumpet Follow-On (by some referred to as Trumpet FO-2) debuted on the NROL-35 mission in 2014 using the more powerful Atlas V 541 rocket with four instead of one booster and a larger fairing diameter, indicating the satellite mass and size had grown. There have been reports that the FO-2 satellites are substantially different than their predecessors in terms of technology, but their overall mission architecture remains the same – complementing the Orion satellites in GEO by collecting a variety of signals intercepts over the northern hemisphere through a very large deployable antenna.

Speculative information claims that the satellites host large deployable mesh antennas with a diameter of over 100 meters to pick up even faint radio signals over foreign territory to allow insight into activity at military installations and other sites of interest. It is speculated that the Trumpet satellites were manufactured by Boeing.

The Trumpet satellites are operated in a Molniya Orbit which is a highly elliptical orbit at an inclination of 63.4 (in this case) or 116.6 degrees with a period of half a sidereal day (~12 hours) and a high apogee around 37,000 to 40,000 Kilometers. This type of orbit was first used by a series of Russian military communications satellites known as Molniya (Lightning).


Molniya Orbit Design – Image: NASA

Choosing an inclination of 63.3 or 116.6 degrees allows the satellite to have a constant argument of perigee of 90 or 270 degrees because the orbits are not perturbed by the gravitational field of Earth (J2 term of the Geopotential Model). This allows the satellite to have a constant perigee and apogee location on Earth over the course of its mission – for Molniya orbits, apogee is located above the northern hemisphere.

Relative to Earth, the satellite's speed is slowest at higher altitudes, meaning that the spacecraft spends the majority of its time around apogee. Communication satellites in Molniya orbits operate for eight hours per orbit centered around the apogee passage. Reconnaissance spacecraft take advantage of the long apogee passage to observe target locations at virtually any point in the northern hemisphere.

The major benefit of a Molniya orbit despite being less energetic than GEO is the coverage of the polar regions which is in many cases not possible from Geosynchronous Orbit due to low elevation angles.

Current NRO programs using Molniya Orbits are the Trumpet electronic intelligence satellites and the HEO Segment of the Satellite Data System which includes spacecraft in Geostationary Orbit and satellites in Molniya Orbits.

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tnt22 пишет:  http://spaceflight101.com/atlas-v-nrol-42/wp-content/uploads/sites/180/2017/08/20140609111109USA202_Thuraya2-512x386.jpg

Хорошая картинка, наглядная.

[tnt22]

http://www.vandenberg.af.mil/News/Article-Display/Article/1319974/the-4th-sls-keeping-the-mission-on-track/

The 4th SLS: Keeping the mission on track
By Senior Airman Ian Dudley, 30th Space Wing Public Affairs / Published September 21, 2017



VANDENBERG AIR FORCE BASE, Calif. --
Vandenberg will launch a United Launch Alliance Atlas V rocket, carrying a National Reconnaissance Organization payload, Sept. 21.

The 4th Space Launch Squadron is one of the many critical teams working to ensure the launch goes off without a hitch.

The 4th SLS ensures the risk of vehicle failure during launch is as small as possible.

Спойлер

"All of the missions we conduct have one main focus; mission assurance," said Lt. Col. Kenneth Decker, 4th Space Launch Squadron commander. "The government doesn't buy insurance for their launches, so the way I look at it is that we are the eyes and ears on the ground. We are watching the processing of the vehicle as we proceed to the launch date. For mission assurance we are tracking the vehicles and we are doing an independent risk assessment of them. We then provide that information back to the Space and Missile Center. They are the program office for the launch vehicles. We also work directly with the space craft customer, which in this case is the NRO."

While mission assurance is the bread and butter of the 4th SLS, they also provide critical communication between all parties involved in the mission.

"We provide mission integration, which is the role of our launch mission managers," said Decker. "These individuals are helping to facilitate communication between those various organizations that are part of the mission, such as the program office at SMC in Los Angeles, the NRO which is the space vehicle lead, and the 30th Space Wing which provides the safety and the range support, as well as the infrastructure. We also monitor launch infrastructure because we want to ensure the integrity for future launches."

Maj. Alexander Chumpitaz, flight commander technical assurance flight is serving the critical role as the Air Force launch director for the NROL-42 mission.

"This is how I end my Air Force career, since I will be retiring in the spring," said Chumpitaz. "I have been a space operator and served down range, and seen first-hand the effects from the satellites that Vandenberg has placed in orbit. It's a really humbling experience, and to be a part of the early stages of the operation is fantastic. This whole thing has been a long process, correcting issues that we hadn't anticipated, and just pushing through to keep everything on the right schedule."

With less than 50 members, the 4th SLS stays quite busy covering four primary areas, mission assurance preserving launch capabilities, mission integration and operational assessment.

"Mission assurance involves ensuring the integrity of all the processing on the pad," said Decker. "Mission integration, which involves complex coordination with all the organizations involved in the launch. Preserving launch capabilities, which involves the inspection of infrastructure. And the last thing we do is on the day of launch, we provide an operational assessment to the mission director and the space launch commander."

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[tnt22]

Chris B - NSF‏ @NASASpaceflight 19 мин. назад

Some concerns the Atlas V launch with NROL-42 won't be launching tonight. Webcast still counting down, however.

:?:

[tnt22]

NRO‏Подлинная учетная запись @NatReconOfc 3 ч. назад

The #AtlasV stands 196 feet tall or about 20 stories and weighs more than 1 million pounds fully fueled. #NROL42

[tnt22]

ULA‏Подлинная учетная запись @ulalaunch 20 мин. назад

The #AtlasV #NROL42 mission has been delayed to allow the team time to replace a faulty battery on the booster. @NatReconOfc