1/7 Tonight at 1:25 UT (3:25 CEST), there will be another launch of 60 #Starlinksatellites by @SpaceX.
On the 1st revolution, sighting opportunities for this launch are (ignoring the weather) good for the US East Coast, northwest & southeast Europe, as well as the Middle East.
2/7 Unfortunately parts of NW Europe (NL, B, UK) will probably be clouded out tonight...
Nevertheless, sky maps for a few places in Europe:
3/7 (cont.)
4/7 The release of the satellites from the Falcon rocket is about 15 minutes after launch, before the pass over Europe. During the pass over Europe they will be a thight clump close to the Falcon 9 Upper Stage. While visible by the naked eye, use binoculars to separate objects.
5/7 While the 60 #Starlink satellites will not be a 'train' yet tonight, over the next 3 nights or so after tonight, we should see the "train" form, with good passes over Europe.
If only weather cooperates....
6/7 In order to reduce visibility after (a.o.) astronomer complaints, SpaceX will put the satellites in a different orientation after a few days, which should make them fainter from that moment on. Also, one experimental satellite has a 'sunshade' that should reduce brightness.
7/7 For those who know how to work with TLE's for pass predictions: I have put an estimnated TLE for the first revolution here: launchtower.langbroek.org
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So, I did some simulations with GMAT.
Assumptions:
- For totally arbitrary drag area of 1 m^2;
- Near-orbital speed at disintegration;
- disintegration at 148 km;
labels are mass in kg of fragment.
@planet4589 @DJSnM @Ian_Benecken
2/x additional info: no mass loss due to ablation upon reentry (this is important: if they do loose mass 9and they will), they come down earlier than in the map)
3/x Nevertheless: they appear to be surviving a lot further downrange than I actually had anticipated.
1/x The very successful @AETUDelft-built 3U cubesat Delfi-C3, launched 15 yrs ago, is near the end of its life. It will probably reenter into the atmosphere next month.
Yesterday evening, I managed to image it with my tracking camera from Leiden, the Netherlands:
2/x Here is the video footage (it is very faint, being a 3U cubesat, i.e. 10 x 10 x 30 cm large). Footage was shot at 25 fps with a WATEC 902H2 Supreme and Samyang 2.0/135 mm lens.
3/x Over the past months, the cubesat has been coming down increasingly fast. Currently it is in a 351 x 365 km orbit (when launched in 2008, it was at 615 x 635 km)
Approximate trajectory flown by the #ICBM that #NorthKorea tested today. A highly lofted trajectory.
(reconstruction based on Japanese DoD info).
When launched on a 'normal', non-lofted trajectory, the range would be 18000+ km, i.e. capable of reaching any place on Earth
Trajectory is based on rough information on apogee, range, and map with approximate impact point provided by Japanese DoD here: mod.go.jp/j/press/news/2…
It will be interesting to see what missile it concerns when Northg Korea publishes their propaganda photo's. Hwasong-17? Something new?
USA 326 (2022-009A) was launched on February 2 this year and is believed to be a new generation of electro-optical reconnaissance satellite: sattrackcam.blogspot.com/2022/02/the-up…
It is in a 97.4 deg inclined, 518 x 488 km orbit.
The Russian launch today was indeed at 20:25 UTC, right at the moment the USA 326 orbital plane passed over Plesetsk (i.e. the launch was into the orbital plane of USA 326): interfax.ru/russia/854824
2/x To be clear (as such suggestions always arrise):
This has *nothing* to do with the Ukraine crisis. Tests like these are scheduled months in advance.
They are regular tests to ascertain the readiness and training of missile crews.
3/x As I expected, another Navigational Warning has appeared, adding an extra hazard area west of Kwajalein.
Updated map for this upcoming #Minuteman III test (probably GT240GM):
2/x ...maar worden echt in een baan om de aarde gebracht, zoals een satelliet. Waarna op een gegeven moment met een deorbit burn door een retroraket, de lading weer omlaag wordt gebracht, boven het doelwit.
Welnu: waarom zou je dit zo doen in plaats van een normale ICBM lanceren?
3/x Het voordeel van FOBS is dat het je toestaat toe te slaan vanuit richtingen die met gewone ICBM's niet worden verwacht. Via een traject over de zuidpool bijvoorbeeld. Dan benader je de VS (het doelwit) vanuit het zuiden (gele lijn), terwijl