# Tag Info

29

Tl;dr, From personal experience, it’s not worth it. It’s a lot easier to throw away bad data than to try to calculate when stop. There’s not a lot of ambiguity as to whether it messes up the data. As of right now, it’s not that big a problem either. Sure, some are particularly unlucky, as seen with a Magellanic cloud observation in early 2020. The concern is ...

23

To add to @Planetmaker's concise yet complete answer: In order to keep at least one satellite in the sky over Russia (or any other high N or S latitude area) at all times, the Molniya orbit was invented. source It is not stationary or even synchronous, but with a period of exactly 1/2 sidereal day it is repeat-ground track. It will appear to linger for ...

21

No. A geostationary satellite is in an orbit around the earth with a 24 hour period - in the same sense of rotation as the Earth rotates. That makes sure that its orientation with respect to the surface of Earth does not change. If you put a satellite into another orbit which is not around the equator, it changes the latitude, thus cannot ever be geo-...

16

Satellites just add moving lights to the sky, they do not obscure stars. However, some may find that disrupting their view of what a sky should look like. The visual magnitude of starlink satellites is about 5.92 at zenith, and usually darker (but also sometimes brighter). The new darker satellites are about 0.77 magnitudes fainter. This is in the lower ...

11

A nightmare for star hopping I can only speak as an amateur astronomer with a 10-inch Dobsonian. My telescope has no GOTO or tracking, so if I want to find something interesting in the sky, I have to use star hopping: taking bright stars (up to ~mag 5) as reference points, I point the finder in the approximate direction. through the finder, I can see dimmer ...

8

It is called Tidal love number. The definition is as follows: In Newtonian gravitational theory, a tidal Love number relates the mass multipole moment created by tidal forces on a spherical body to the applied tidal field. The Love number is dimensionless, and it encodes information about the body's internal structure. (Poisson et.al., 2009) For Io, the ...

6

Depending on your definition of satellite; maybe yes. Only over the equator can you have a satellite in a Keplerian geostationary orbit. This idea is covered in depth in other answers. I would note that even these satellites are not totally without means of propulsion. They need to be able to generate thrust occasionally to make corrections to their orbit. ...

6

$k_2$ is one of three tidal Love-Shida numbers related to how gravitation of another body (Jupiter in this case) changes a planet-like body's second degree spherical harmonics (Io in this case). Three Love and Shida numbers exist for each degree of spherical harmonic coefficients. The three Love-Shida numbers for a given degree $n$ are $k_n$, which ...

3

I'm not a spectroscopist, but, I know a fair bit about spacecraft data reduction. CRISM is a spectrometer that's very sensitive, but it needs more light than it can get by just riding along with the spacecraft, so it slews in the reverse direction of motion (that's why CRISM images have that hourglass shape). Despite that, it STILL has some light issues ...

3

Both ESA and NASA have a policy that data need to be made available after a certain grace period. Look at the respective satellite mission like you look at the sentinel mission pages and you will likely be able to find the ressources or links to them. E.g. for Mars express, the data are all gathered in the data archive on https://www.cosmos.esa.int/web/psa/...

2

A satellite has a centrifugal force* radially away from the center of its curvature. If the orbit is in a plane that does not go through the center of mass of the Earth, then the centrifugal force will be at an angle to the ray going from the satellite and the center of mass of the Earth. Since gravity acts only through this ray, gravity can't completely ...

2

When you point your 25 cm aperture Newtonian reflector at the Sun you're concentrating sunlight to about 50 watts per square centimeter. About half of that is in IR/UV and will be absorbed in many kinds of optical glass and the rest will be available for imaging, and way too much for it! If you want to use your full aperture, then you must put a special ...

2

Dark or bright features does not matter - the resolution stays the same. Resolution is achieved when the diffraction pattern is such that two maxima or two minima can be distinguished. Many pictures exist of the ISS in front of the Sun or the Moon, and 10" is definitely a telescope with enough aperture. The question one has to ask is: do you mean to ...

2

Satellites are provided by a plug-in (that is enabled by default) Configuration (the spanner-and-star button) -> plug-ins -> Satellites -> configure. You can configure which satellites to display from here. It might be worth noting that meteosat-8, a geostationary satellite has a magnitude of about 19, and so is not a naked eye object, and is in ...

1

It doesn’t seem possible to have a general view of selected satellites, however the bookmark plugin seems the best workaround to keep a custom list without having to search satellite plugin configuration panel each time.

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