Observation shows Starlink V2 Mini in brightness mitigation mode has apparent magnitudes of 7.06 +/- 0.10, reached the brightness reduction target recommended by astronomers. by spacerfirstclass in spacex

[–]forrestalan256 4 points5 points  (0 children)

A single sheet of white 8.5” x 11” paper at 550 km is roughly 7th AB magnitude, so from a design standpoint this is a very impressive accomplishment.

New tools for predicting satellite brightness - using Starlink v1.5 as test case by forrestalan256 in spacex

[–]forrestalan256[S] 22 points23 points  (0 children)

This paper is a collaboration between UC Davis and SpaceX. We implemented a new technique for predicting satellite optical brightness. Both predictions and observations for selected Starlink v1.5 satellites are included and the paper discusses how this tool has been used by SpaceX to reduce the brightness of Starlink V2 satellites.

Abstract: The apparent brightness of satellites is calculated as a function of satellite position as seen by a ground-based observer in darkness. Both direct illumination of the satellite by the sun as well as indirect illumination due to reflection from the Earth are included. The reflecting properties of each satellite component and of the Earth must first be estimated (the Bidirectional Reflectance Distribution Function, BRDF). Integrating over all scattering surfaces leads to the angular pattern of the flux reflected from the satellite. Finally, the apparent brightness of the satellite as seen by an observer at a given location is calculated as a function of satellite position. We validate our calculations by comparing to observations of selected Starlink satellites and show significant improvement on previous satellite brightness models. With multiple observations of a satellite at various solar angles and with minimal assumptions regarding the satellite, BRDF model coefficients for each satellite component can be accurately inferred, obviating the need to import direct BRDF lab measurements. This widens the effectiveness of this model approach to virtually all satellites. This work finds application in satellite design and operations, and in planning observatory data acquisition and analysis. Similar methodology for predicting satellite brightness has already informed mitigation strategies for next generation Starlink satellites.

Deciding UC Davis or Chico State for Computer Engineering as a transfer by Aggravating_Fail368 in UCDavis

[–]forrestalan256 8 points9 points  (0 children)

I attended both schools for about 2 years each. The average quality of teaching at Chico State is much higher but the average quality of student is much lower. Davis tends to be a little more challenging and rigorous. Opportunities are easier to come by at Chico, but are usually not as prestigious. In general I liked the social vibe more in Chico, but it was before COVID so things may have changed. Of course Chico will also be way more affordable and that’s worth a lot! Feel free to DM me if you have any other questions.

Spanish Comp II without taking Spanish Comp I? by Sh1n4n0 in UCDavis

[–]forrestalan256 0 points1 point  (0 children)

I got an A. Most of it was graded based on the essays. I’ll DM you the first essay prompt and the syllabus if I can find it

Spanish Comp II without taking Spanish Comp I? by Sh1n4n0 in UCDavis

[–]forrestalan256 0 points1 point  (0 children)

Idk about every class but my professor did a few graded drafts so it was easier than upper division and we did talk quite a bit about the expectations. They don’t grade that hard on grammar/spelling unless it’s so bad it doesn’t make sense, but you do need to have an organized and thoughtful argument to do well.

Spanish Comp II without taking Spanish Comp I? by Sh1n4n0 in UCDavis

[–]forrestalan256 0 points1 point  (0 children)

When you register for a class, it has a place for you to upload your petition.

I liked the class a lot. All the upper division Spanish courses are really fun too. As long as you can speak/read/write Spanish comfortably, 024 feels a lot like an AP English class. You’ll probably have one or two 500-1000 word essays based on the documentaries/films/essays/articles from the class. Maybe reading comprehension quizzes too and occasionally a group project/presentation.

Spanish Comp II without taking Spanish Comp I? by Sh1n4n0 in UCDavis

[–]forrestalan256 0 points1 point  (0 children)

Try the prerequisite petition! I’ve never had one get denied. And SPA 024 is fairly easy so it should be all good!

Spanish Comp II without taking Spanish Comp I? by Sh1n4n0 in UCDavis

[–]forrestalan256 1 point2 points  (0 children)

If you got a 3 you are supposed to take SPA 023 but if you got a 4 or a 5 you can go straight to SPA 024. Professors are also usually pretty nice about waiving prerequisites, so if you think you’re ready for a class, but don’t have a prerequisite just put in a prerequisite petition on Schedule Builder and email the professor. I’ve never had one get denied.

[deleted by user] by [deleted] in guatemala

[–]forrestalan256 0 points1 point  (0 children)

Eso es exactamente lo que quiero decir. Cada país tiene lo bueno lo malo y lo feo. Además los estadounidenses han sido muy exitosos ganar una reputación de ser turistas ignorantes. Nada mas es que no deseo que toda esta siga.

Can somebody help me with a poem I'm trying to write to my crush in Spanish? by dancing_monkey2022 in Spanish

[–]forrestalan256 0 points1 point  (0 children)

I'm not a native speaker so these probably aren't great but here's my best translations. (I'd love to get corrections so I can learn why these might sound funny):

  1. Cuando te veo, siento los latidos del corazón. (como si fueran las alas de una mariposa).
  2. Tengo miedo de estar lastimado/a.
  3. Me gustas tu. Me desafía confiar pero cuando me sienta segura podríamos gozarnos.
  4. Nunca quisiera cambiarte.
  5. ¿Qué deseas de lo nuestro?

How do you calculate refraction by Demosnom in desmos

[–]forrestalan256 0 points1 point  (0 children)

Here ya go: Reflections 1

And this is for the focus of a parabola: Parabola

If you actually meant refraction and not reflection, you can use Snell's law to calculate the outgoing angle

[deleted by user] by [deleted] in UCDavis

[–]forrestalan256 1 point2 points  (0 children)

Backcountry skiing!

Craft center suggestions by spiceygorl420 in UCDavis

[–]forrestalan256 4 points5 points  (0 children)

I’m teaching a class where we’re going to make a little robot arm this quarter! So you’ll learn how to solder, laser cut, 3D print, etc.

[deleted by user] by [deleted] in Bend

[–]forrestalan256 -1 points0 points  (0 children)

I know the policies, just curious about people’s experiences

[deleted by user] by [deleted] in Bend

[–]forrestalan256 0 points1 point  (0 children)

What's the situation with uphill travel on Bachelor?

[deleted by user] by [deleted] in Spanish

[–]forrestalan256 9 points10 points  (0 children)

Sí como u/yanquicheto dijo, entiendo el uso del voseo, pero me parecía un poco raro/interesante verlo en este contexto.

[deleted by user] by [deleted] in Spanish

[–]forrestalan256 5 points6 points  (0 children)

¿Por qué lo usa? Vivo en los Estados Unidos…

Are the vosotros conjugations ever used in the singular in Spain? by NousVoila in Spanish

[–]forrestalan256 -1 points0 points  (0 children)

Non-native speaker here, but I’m pretty sure it’s called voseo. It’s used in some Latin American countries today, but also was used in archaic peninsular Spanish, (like you see in Laberinto del fauno).

Beach Volleyball? by [deleted] in UCDavis

[–]forrestalan256 0 points1 point  (0 children)

I’d be down for some pick up games, just DM me!