ORS-3 Launch of 2013 Nov 20

Coverage started 2013 Nov 18

Updated 2013 Nov 20

On 2013 November 20 at 01:15:00 UTC (window is 00:30:00-02:15:00 UTC), a Minotaur 1 booster carrying 29 satellites is scheduled to launch from the Wallops Island, Virginia on the east coast of the US. The latest information I have seen shows this launch should include:

    STPSat 3, ORSES, ORS Tech 1, ORS Tech 2, Prometheus 1, Prometheus 2, Prometheus 3, Prometheus 4, SENSE 1, SENSE 2, Firefly, STARE B (Horus), TetherSat 1, TetherSat 2, Black Knight 1, NPS-SCAT, CSIP, COPPER, ChargerSat 1, TJ3Sat, Trailblazer 1, Vermont Lunar Cubesat, SwampSat, CAPE 2, DragonSat 1

A description of the ORS-3 launch manifest can be found on Zarya.com and Spaceflight Now.

As was seen on the Falcon 9 launch of 2013 Sep 29—carrying Cassiope, CUSat 1/2, DANDE/LAB, and POPACS 1, 2, and 3—tracking and cataloging multiple payloads can be challenging. For those who have the proper equipment (these objects will likely be too dim to see with the naked eye) and would like to observe or track the objects associated with this launch, I have created an STK Viewer file that shows those areas on the Earth's surface where these objects should be visible for the first 24 hours after launch.

Figure 1 shows those areas on the Earth's surface where the ORS-3 payloads should be visible over the first 24 hours after launch (assuming a launch at 0030 UTC).

The orbit for a nominal payload was derived by taking the launch profile provided on the Orbital Minotaur I/ORS-3 web page, which is provided as a Google Earth .kmz file (linked at the bottom of the page), converting the latitude, longitude, and altitude information into an STK ephemeris (.e) file, and then fitting the last 40 seconds of the trajectory to produce a TLE. That yields an orbit consistent with the information from the last official ORS-3 press release (494 km x 506 km altitude, 40.5-deg inclination).

Note that the payloads will start to drift apart due to the deployment sequence and differential drag shortly after launch and deployment. Observers in the middle latitudes of the northern hemisphere will be able to see this launch, unlike that of the Dnepr launch on 2013 Nov 21.

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Figure 1. View of visiblity regions for first 24 hours after launch

Visibility regions (the yellow areas on the globe) were generated using STK Coverage to show where the nominal orbit should be visible to an observer on the ground when the object is 10° or more above the horizon, the Sun is more than 6° below the horizon (civil twilight), and the object is in direct sunlight.

Figure 2 shows the instantaneous visibility (green area) over South Africa as this launch makes its first appearance over land in the southern hemisphere. It is unlikely that any of the payloads will have been deployed by this point in the mission, so only one object should be visible. The orbit is shown in green when in sunlight and gray, otherwise.

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Figure 2. View of first southern hemisphere visiblity over South Africa

Figure 3 shows the instantaneous visibility over the western US and Canada as this launch makes its first appearance over land in the northern hemisphere. Some, if not all, of the payloads should be deployed by this time.

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Figure 3. View of first northern hemisphere visiblity over Western US and Canada

If you would like to explore this event in more detail, simply download the STK Viewer file below. I hope you find this information both informative and helpful. If you have any questions, please feel free to ask. And if you manage to collect any images of these passes, I would be happy to add them to the coverage here.

Download ORS-3 Launch Orbit Visibility Scenario

Note: STK Viewer is a free product which allows anyone with a Windows computer to view an STK (System Tool Kit) scenario. With it, you can animate a scenario forward or backward, pause the animation, and zoom or pan the view for a more complete understanding of the event. Just like with Adobe Acrobat, where the authoring software requires a license but the Adobe Reader is free, STK can produce STK Viewer files—also known as VDFs—which can then be viewed by anyone with the free STK Viewer software. You can find the STK Viewer on CelesTrak here. — TS