Quote from: Comga on 07/14/2016 04:30 pm$492M / 9 =$54.7M for each launch with a new rocketIt is 7 launches.492/7 = 70.3 M but that probably includes the dispenser built by SpaceX.Edit: The article says 7 launches. But it also says 81 satellites. I believe 2 will fly on a russian rocket. That still leaves 79, so 8 flights with 10 each unless they will have ground spares.
$492M / 9 =$54.7M for each launch with a new rocket
Is the system still going to be 6 planes with 11 working sats each. that makes 7 launches of 10 sats seem a little odd. And, will some of the spares stay on the ground till needed?
The operational Iridium constellation requires 66 satellites — 11 spacecraft in six orbital planes — for global coverage serving more than 800,000 subscribers.Enough Iridium Next satellites should be launched by the end of 2017 to fully replace the first-generation fleet, allowing controllers to retire and de-orbit the old spacecraft. Iridium has launch contracts with SpaceX and Kosmotras for 72 satellites, but Desch said the company plans to eventually launch all 81 birds.
Quote from: Nomadd on 07/14/2016 06:23 pmIs the system still going to be 6 planes with 11 working sats each. that makes 7 launches of 10 sats seem a little odd. And, will some of the spares stay on the ground till needed?70 launched by SpaceX, plus the 2 that were to be launched by the Russians first, would have been 72 orbital, allowing for 6 planes of 11 operational plus a spare. Sounds right to me.
Spare satellites are usually held in a 414 mi (666 km) storage orbit.[2] These will be boosted to the correct altitude and put into service in case of a satellite failure. After the Iridium company emerged from bankruptcy the new owners decided to launch seven new spares, which would have ensured two spare satellites were available in each plane. As of 2009 not every plane has a spare satellite; however, the satellites can be moved to a different plane if required. A move can take several weeks and consumes fuel which will shorten the satellite's expected service life.Significant orbital plane changes are normally very fuel-intensive, but orbital perturbations aid the process. The Earth's equatorial bulge causes the orbital right ascension of the ascending node (RAAN) to precess at a rate that depends mainly on the period and inclination. Iridium satellites have an inclination of 86.4°, so every satellite in a retrograde (inclination < 90°) orbit, their equator crossings steadily precess westward.[citation needed]A spare Iridium satellite in the lower storage orbit has a shorter period so its RAAN moves westward more quickly than the satellites in the standard orbit. Iridium simply waits until the desired RAAN (i.e., the desired orbital plane) is reached and then raises the spare satellite to the standard altitude, fixing its orbital plane with respect to the constellation. Although this saves substantial amounts of fuel, it can be a time-consuming process.
Edit: The article says 7 launches. But it also says 81 satellites. I believe 2 will fly on a russian rocket. That still leaves 79, so 8 flights with 10 each unless they will have ground spares.
Enough Iridium Next satellites should be launched by the end of 2017 to fully replace the first-generation fleet, allowing controllers to retire and de-orbit the old spacecraft.
I believe the lack of a Dnepr is due to the ongoing embargo foodfight. What are the odds that'll spill over io Proton and Soyuz?Also, documenting the new SpaceX satellite dispenser shown in the article. 'CommX' too?
Also, documenting the new SpaceX satellite dispenser shown in the article. 'CommX' too?
Well you do still have NOSS satellites and Envirosat can produce very nice flares.
Dnepr is a joint Ukrainian/Russian vehicle, which is why it is no longer flying. It has nothing to do with Proton/Soyuz.
Will they be bringing the old sats down once NEXT is fully up? That would make for a good light show. Or is fuel too far gone for that?
De-orbiting satelits for show.. There is actually a "fireworks" display planned for the Japanese Olympic games opening in 2020 that consists of de-orbiting a few hundred little particles of some mm in size.http://global.star-ale.com/project/canvasUnfortunately this is completely off topic and might be better discussed in a separate thread.
Back on topic, does anyone have an estimate for the mass of the dispenser?
Hawthorne, California-based SpaceX is building the 1,000-kilogram dispenser that will separate the 10 satellites into or bit on release from the rocket.Each Iridium Next satellite will weigh 860 kilograms at launch, for a total satellite payload mass of 8,600 kilograms, plus the 1,000-kilogram dispenser
On Tuesday, June 21st, SpaceX shipped the first Falcon 9 Iridium NEXT satellite dispenser to the Vandenberg Air Force Base launch site in California, and on Monday, June 27th, it was confirmed that the dispenser arrived safely. ...In order to accommodate a payload of this size, SpaceX developed a Falcon 9 satellite dispenser unit that was capable of managing the critical-timed separation and deployment of ten satellites from each rocket. These dispensers were built out of a carbon fiber composite to reduce mass, minimize the total number of parts and simplify their composition while increasing structural stiffness and strength. The design of this dispenser places the Iridium NEXT satellite vehicles in two separate stacked tiers around the outside of each dispenser, holding five satellites per tier. “We’re excited for the upcoming first launch of Iridium NEXT and proud of the work we’ve completed for the Iridium NEXT program. This is one of the heaviest payloads we will fly to-date – 10 Iridium NEXT satellites weighing over 20,000 pounds,” said Kris Kroc, mission manager at SpaceX.Now that the dispenser is at the launch facility, the team will be running a series of end-to-end electrical tests with the tiers separated, as seen in the accompanying photo.
