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8

The silvery/mirror like surface on the spacecraft are Optical Solar Reflectors. They are very effective radiators to dissipate the internal heat from the spacecraft. The mirror effect reduces absorption (i.e. reflects visible light where the Sun's intensity is strongest) while the quartz material itself radiates very effectively in the infrared (i.e. ...


8

An excellent review of all of the considerations and work that has gone into designing TESS' orbit can be read in the ArXiv preprint A High Earth, Lunar Resonant Orbit for Lower Cost Space Science Missions and I'll draw primarily from this, and the excellent YouTube video Transiting Exoplanet Survey Satellite (TESS). The development of TESS' remarkable ...


7

You're right; these objects aren't lost. However, Space-Track doesn't actually track a lot of higher-orbiting objects. They just don't seem particularly interested in anything with a multi-day orbit; I don't know why. Of the four objects you mention, TESS and IBEX are tracked by the people operating those missions. I know of no public data for IBEX, ...


6

The short launch window appears to be due to a combination of the very precise orbit requirements of TESS and SpaceX's tendency to bravado. Other Sources: Information on the exact reasons is thin on the ground and I've read several contradictions (or maybe there are just multiple reasons): From here (from OP in comments): On each launch day, the daily ...


6

I believe it is an effect of the used 3d->2d projection and relative angles of the camera and the shown orbit. I replicated similar Earth center shift using Online Space Orbit Simulator site and changing the default parameters of a random elliptical orbit to make it eccentric and inclined: e = 0.5 i = 75 Only the XZ and YZ views seem to keep the Earth in ...


5

Yes, P/2 means half the lunar period, and P/3 means a third. There's a discussion of the new IBEX P/3 orbit, including a cool image, here. The 90 degrees is a requirement because it stays away from the Moon. Consider the orbit of the moon as a circle labelled as a clock. The moon goes from 12 to 3 to 6 to 9 to 12 in one period. In a half a period, ...


4

Uhoh, I'll jump in the deep end and take a shot at this since you've been waiting 2 months for an answer, there certainly are people better qualified than I to answer this as I've limited my efforts to what I could come up with over several hours. Improving edits welcome. The fabric is simply a means to hold something like CoBlasted Solarblack (they might ...


4

The fuzzy light you mention are diffraction effects and the light baffles used are rectangular, which would give you the four-sided pattern. There is a paper that goes over the optical design where they also address the anticipated stray light effects (including back-reflections, known as ''ghost'' reflections). I don't know anything about this ...


3

From NASA_TESS on Twitter: @NASA_TESS Mission Update: #TESS successfully completed a lunar flyby on May 17. TESS completed scheduled contact with @NASASCaN's Deep Space Network. Post flyby tracking was confirmed. TESS was 8,253.54 km from the surface of the moon at its closest approach. And an update: @NASA_TESS Mission Update: Based on great ...


3

3D to 2D is not primary cause. Primary cause is RAAN of two orbits is different. So when you project 3D to 2D, ellipse is slightly rotated. Infact I claim that the angle by which it looks tilted w.r.t to moon orbit is exactly the RAAN difference between two orbits.


2

They are not designed by the same groups at all. OSIRIS-REx was designed by Lockheed Martin, including the antenna. The diameter is 2.1m, and operates on 8445 MHz. TESS, on the other hand, has a 0.7 m antenna built by Orbital-ATK (Now Northrup Grumman, but...) The frequency is in the Ka band, which is 26.5- 40 GHz. Basically they look a lot alike because ...


2

@jkavalik's answer seems to have nailed it, I'll add my own perspective (no pun intended, seriously!) as background. When I looked at the problem I first considered and then rejected distortion due to projection (the orbit being much closer to the viewer or camera in some places than in others) because the orbit still looked perfectly elliptical, just ...


2

I'm afraid there is nothing terribly exciting about the "ripples". They are just artifacts of the manufacturing of the graphite composite fabric that is used for the shell of the dish. The shape is a plain vanilla reflector (axis displaced reflector, if you must know) with no important surface features. And as was mentioned, before launch the whole ...


2

It seems the plan is to land the booster at sea, because it will be a softer landing, presumably because it uses less fuel, and can afford a more gentle decent. https://twitter.com/ChrisG_NSF/status/984807602080174080


1

As you note, usually smaller payloads can RTLS (Return To Launch Site). Also some higher energy missions the first stage needs to land down range. SpaceX is not publicly listing the plans for each mission but a number of sites are trying to collect all information and format it. So Reddit r/spacex has a pretty good listing of future missions, with ...


1

The ITU does the allocations in this area. There's been some recent activity to increase allocations for "space research communication" in these bands, but that's not worked it's way through the chain yet (AFAIK). Still, we can give a partial answer to "Are there now approved Near Space Ku Band frequencies" by referring back to the prior round. The 2014 ...


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