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15

A self-sufficient orbiting telescope is basically Hubble mkII and would never get off the ground, literally and metaphorically Hubble was expensive because it was state-of-the-art, requiring development of many new systems. The systems it needed to function as a standalone satellite (compared to being attached to the ISS) were cheap by comparison (reaction ...


9

Attach a visible light telescope to the outside of the ISS This is a reasonable idea and it has been thought of before, but usually for other-than-visible light. Other answers do a good job of explaining why the disadvantages substantially outweigh the advantage. The cost to put something on the ISS large enough to outperform the top few dozen telescopes on ...


4

I think you'd want a focal length of 700-1000 mm, and the cheapest way to get that would be a basic Newtonian reflector of 100 mm aperture. Examples: Meade Polaris 114mm, Celestron PowerSeeker 114EQ, Orion SkyQuest XT4.5. There are brackets available to mount a smartphone on any telescope. Before trying to track ISS, practice acquiring easy targets such as ...


3

No such thing as a Nikon P9000 .... there are the P900 and P1000 model cameras, which come with a non-detachable lens, which can be zoomed to extreme focal lengths, included. These have indeed a good reputation for a viable solution for moon or even basic planetary shots, however these - being NON-interchangeable lens cameras - would be an exceptionally BAD ...


3

Objects in orbit pass over the surface above what's commonly called their ground track. For objects in low earth orbit, though they go around the earth every 1.5 or more hours, the Earth rotates beneath them so they don't trace a simple "circle" over the same points on land. The orbit is around the Earth in a fixed plane, so we are likely (but not ...


3

This is for satellites with unknown size and orientation but known standard magnitude (Standard magnitude can be found on the satellite info page of heavens above, the number is called intrinsic magnitude) The proper formula is double distanceToSatellite = 485; //This is in KM double phaseAngleDegrees = 113.1; //Angle from sun->...


3

The ISS Transit Finder offers such predictions up to 30 days ahead. If a query yields no transits at the specified location, the "Show on Map" button for a close pass shows where a transit would be visible. As the documentation notes, predictions beyond 10 days are rather uncertain. Recent versions of Stellarium can show ISS's apparent position at a given ...


3

First you should get an idea of what "Anomaly" means. An anomaly is an angle which can describe the position of the satellite in its orbit. The true anomaly is the actual angle made between the position of the satellite and the perigee. The true anomaly changes quickly when the satellite is close to the Earth and slowly when it is far from the Earth. The ...


2

Congratulations to @NickBrown for his solution! Based on that equation and some additional references I'll just add a little more. https://apps.dtic.mil/dtic/tr/fulltext/u2/785380.pdf https://www.researchgate.net/publication/268194552_Large_phase_angle_observations_of_GEO_satellites Calculating visual magnitude takes three input parameters how good of a ...


2

I have certainly watched the ISS and an undocked Shuttle Orbiter chase each other across the sky. Since they appeared to be of equal brightness, I didn't know which was which. Their angular separation from my POV was approximately 20°, so their actual separation would have been about 150km. It was one of the last Shuttle flights, so I was very lucky to see ...


2

Heavens-Above shows two fairly bright objects passing over Nuremberg at that time on 2020-04-14: a Resurs-O1 rocket moving south to north an Iridium-4 rocket moving north to south The next visible ISS passes at your location are between April 28 and May 3, all before dawn.


1

Draw the triangle Sun-Earth-Satellite, we will first find the angle Sun-Earth-Sat. The angle between the Sun, the observer, and the satellite will be the angular separation between the Sun and the satellite on the observer's sphere. Here is how you could calculate that: You have horizontal coordinates for both bodies so the easiest way to go from there ...


1

The SpaceX YouTube video SpaceX Crew Dragon Returns from Space Station shows the undocking and parts of the reentry and landing. Orbits work a little counterintuitively when it comes to velocity. To drop to a lower orbit the capsule will point it's engines forward so that they receive an impulse backward, but since they loose altitude this way the speed of ...


1

That is RapidScat, described in this answer in the Space Exploration SE.


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