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One feature of Stellarium is that you can click on planets, moons, or asteroids within our solar system and then hit CTRL-G (CMD-G on Macs) to make that your home planet. If you select Callisto or Io and hit CTRL-G, you'll be able to see what the sky looks like from either of those moons.

A good place to start is Introduction to Modern Astrophysics, by Carroll and Ostlie: https://www.amazon.com/Introduction-Modern-Astrophysics-2nd/dp/0805304029 It's a good upper-undergrad to grad-level textbook that covers a lot of topics.

Yup. Any astronomy software/apps can do this.

I use Sky Safari on my phone.

Stellarium is a free PC program.

Just enter the time, date and location you want and it will show you the sky at that point.

Also just to note, the north star (Polaris) would only ever be at zenith from the north pole.

Planets each move on their own orbit around the Sun, so they move at different speeds relative to the background stars. That speed depends on their distance from Earth and the Sun, so the nearby planets like Mars and Venus may be in completely different places just a few months later, while Uranus and Neptune will still be in almost the same spot.

Best way to find them is with software like Stellarium.

> Accretion disks may stretch out light years.

[Citation needed]. As far as I'm aware, black hole accretion disks may be anywhere from 10km to 1000000km in size, well short of light years.

There's no such thing as "above", "below", or "horizontally parallel to Earth" in space. There are telescopes looking in every direction, from the North Celestial Pole to the South Celestial Pole. There are stars, dust, nebulae, and galaxies in every direction. If you'd like to see for yourself what the sky looks like from any point on Earth, looking in any direction you choose, I'd recommend downloading Stellarium.

Download Space Engine. You can go to M110 and view M31 from there.

Here's a screenshot. This is a procedurally-generated planet in M110. The view of M31 should be fairly accurate.

here is the Barycenter of our Sun

Notice how it actually moves around. This is partially due to Jupiter and also due to the the system being rather complex multi-body system.

So what does that mean? For all intents and purposes, everything works the same, especially since the Sun is so massive. But technically, we get wobbles as Jupiter affects the system through its orbit, and we all revolve around The Barycenter regardless of whether it’s in or out of the sun. It all balances out however as we are all in stable orbits at this stage of the game.

If there is game on steam, Universe Sandbox 2 which is an awesome physics based simulation game. You can take our solar system, or create your own systems and see how the physics play out. Give it a go and hope you enjoy!

Why not try going to some star parties? You can try out looking through a scope and see how you like it before investing any money. You might also try downloading Stellarium, both to figure out what you're looking at and to find things to try to look at.

That's the planet Venus. You can download Stellarium to identify stars and planets -- it will show you what's in the sky at any given date and time.

It looks like it was out of focus in the zoomed in picture.

So stars don't have a fixed magnitude. Their brightness changes depending on which part of the spectrum you're looking at. Every telescope has a "filter" or set of filters that only allow light of specific wavelengths through, and how bright a star appears (its magnitude) depends on what filter you're using.

Here is an image showing just a tiny fraction of the filters in common us in astronomy as well as the spectrum of different types of stars at the bottom.

Hipparcos had its own filter, but since it wasn't really doing science that depended on specific wavelengths, it just wanted to collect as much light as possible. So its filter was rather broad, and looked like this.

That's all they mean by Hipparcos magnitude. It's how bright the star was when you filter the light and only allow in the light that passes through their specific filter.

Whenever you look up "apparent" magnitudes of stars, they are giving them to you in one specific filter system (usually something like V as the default).

Take a look at "Universe" by Freedman, Geller, Kaufmann. It's a text book but is very accessible and easy to flick through. Will certainly help to tie things together for you.

You might also consider doing one of the free online courses if you have some time. Something like this one should be pretty good: https://www.coursera.org/course/introastro They also point to this wiki which brings together the main astronomy concepts into one coherent place: http://en.wikibooks.org/wiki/General_Astronomy

Give Stellarium ( http://www.stellarium.org/ ) a try. This is open source software, and is a great way to get familiar with what's in the sky day to day. It would be more helpful to plan an observation than using a paper star chart, unless you can print one out for the time of day that you go observing.

One idea is to join a local astronomy club. Through that you'll meet heaps of people with similar interests.

If you want to do some learning, then there are a number of free online courses that will get you started. Here are some to get you going ...

http://www.open2study.com/courses/astronomy-discovering-the-universe-through-science-and-technology

https://www.coursera.org/course/introastro

This will show you the position of Earth for whatever date you select, and it's 3D:

http://www.solarsystemscope.com/

On a large-scale map that includes the entire galaxy the motion of Earth is far too small to be visible, except on a time scale of millions of years. In that case the motion would look like this:

https://qph.ec.quoracdn.net/main-qimg-8f69a0f62c9148a9cbb02344b5d0d82d-c

There are plenty of open-source projects that see wide use in astronomy (eg. astropy, SciPy), but these are large and fairly mature, so I don't know how receptive they'd be to an enthusiastic amateur (presumably?) wanting to get involved.

An interesting problem to have a go at programming yourself (if that would be of interest) is an n-body simulation, which is the only way to model any more than two planets/stars interacting gravitationally - there's no equation you can write down to describe this. It's relatively straightforward to get a basic program that does this going, but making it efficient and run fast is an interesting and challenging problem.

There is no charge for Stellarium. I have been using it for years.

http://www.stellarium.org/

Click your OS at the top of the page and the application installer should auto-download for you.

I use the Star Chart app for my phone. Hope this helps.

Download Stellarium, enable the satellites plugin, and set the location and time.

Edit: I tried it, and of the satellites that Stellarium shows by default, none seem to match that description.

The only satellite that it showed was Bevo 2, so that might be it.

Although, the description seems a bit like an airplane.

By the way, if you want to see it for yourself, this free program can show you what the sky looks like for your location at any given date and time. It makes it easy to find and identify things in the night sky.

http://www.stellarium.org/

Here's a good map of the Virgo Constellation. Hope it helps.

You may also want to look into the free software Stellarium which you can show labels and constellation outlines. Putting in your location information will put it exactly where you would see it in your sky along with the surrounding constellations to help you pin point it even better.

>I don't know where else to ask this. How can i get a larger image? can you double up 2 x2 Barlow lenses?

The smaller the focal length of the EP, the larger the magnification. You can work it out with 'Magnification = focal length of the telescope/focal length of the EP'. With your scope, your 20mm Ep will give you 50x and the 5mm will give you 200x.

You can stack Barlows. I would recommend getting a more powerful Barlow, such as one of the higher powered TeleVue Powermates, rather than doing this however.

>Will i be able to see anything other than the moon? Can i see stars other than a very small dot? Is Mars out of the question?

The moon will be very bright. I heartily recommend getting a moon filter; preferably a variable one. I have the Orion variable moon filter and it's excellent!

Stars will be different coloured dots with differing levels of brightness (magnitude). You should be able to make out the rings of Saturn, cloud bands on Jupiter and a very hazy level of detail on Mars. It's possible you will make out the polar caps of Mars and Syrtis Major on a very clear night, although below 200mm aperture you will struggle with this small world. You'll certainly see it however! The phases of Venus will also be fairly apparent.

>(I also know how to 3 star align [but it isn't always perfect/accurate])

I can't advise on this, since I'm a Dobsonian guy.

You might want to check out http://www.stellarium.org

It's some very useful free software.

There is a Satellites plugin that might have this data: http://www.stellarium.org/wiki/index.php/Satellites_plugin

It's built-in, so you don't have to download anything. But you probably have to go into the configuration and enable (and/or download ephemeris data for) the particular spacecraft you're looking for.

FWIW, you cannot see New Horizons with an optical telescope, not even something like the Keck. It is simply too faint.

You may wish to download Stellarium. You can put in your location (either in lat/long or a nearby city) and use it as a guide to help you figure out where everything is in the night sky.

This is the 3rd revision I've owned of Smithsonian's "Universe" books.

They give a great history of astronomy, cosmology and physics with wonderful diagrams, photographs and star charts.

I wouldn't recommend another "first" book to a future stargazer. While there are plenty of books out there with good information the book I linked to draws people in with its incredible images of planets, moons, asteroids and comets. Makes the universe feel alive, like an unexplored forest that you can step out into on a clear night.

May I recommend Star Chart?

It is a great, free app where you can add some secondary purchases. If you're a newbie and want to know the name of stars wherever you are, this is great, you just point up to the sky and figure it out.

No rush ;-)

Well, the cometron isn't the worst out of the bunch, good :-)

Well, planets are one of the easier targets, but require a bit more magniication. A decent(!) 3.2mm eyepiece might be pushing things a little, but could be a great addition for planets.

A barlow (that doubles or triples) magnification is another possibility, but the budget ones reduce contrast, and the 10mm kit eyepiece isn't great to start with.

What's great in the telescope are larger clusters (h&chi persei to name one) and nebulae :-)

Grab a star chart app. Most will be able to display RA and Dec grid lines to help you identify it. On this chart the intersection just below and right of Venus is 0 RA, 0 Dec.

If you have a computer, these two programs are great:

https://stellarium.org/ - shows you the sky from any place on Earth at any date and time

http://spaceengine.org/ - shows you what you'd see if you left Earth

m8 there is this great thing called "space engineers". it is a simulator of the universe and it is REALLY high definition and shit, you should download it and try looking for a planet inside of/close by a nebula. here's an example from the developers: http://spaceengine.org/news/blog170729/

Alpha Centauri is part of Centaurus :)

The four main stars of the southern cross are quite far away (80-330 ly), so from Alpha Centauri (4 ly) the constellation would look more or less the same.

Also, Celestia can show you the night sky as seen from other stars.

Any astronomy app can do that. Stellarium is a good one for PC, and free. I use Sky Safari on Android.

You can literally enter in any date and time along with your location (latitude/longitude), and it will show you exactly what the sky looked like (or will look like at a future date). Even if during the day you can just "turn the sun off" to see where the stars are.

Stellarium is an open source software available for all desktop OS and is probably the best tool for this. It also has many more features that you will fall in love with.

http://www.stellarium.org/wiki/index.php/Interface_Guide#Time_Travel

Indeed, try to go out when there's a new moon so that you don't have to worry about it all night. If that's impossible, try to time your outing when the moon has already set or not yet risen. That way the Moon will only be up part of the night and not ruin everything.

If you want to simulate your view of the stars and Milky Way, try Stellarium. Set it to your location and date you want to go out. You're in luck: from the northern hemisphere, the Milky Way is bright and wide in late summer. This is the best time to see the Milky Way core, in the constellation of Sagittarius. Clear skies!

You can use Stellarium (http://www.stellarium.org) to see what the sky will look like from any time (millions of years forward or back in history) and from virtually any place (including from other planets).

Download/install the free application Stellarium. Use it to configure your location, set the date to sometime in June, July, or August 2015 (summer time if you're in the northern hemisphere..) and and step through hours to see what you can expect to "see".

One way would be to combine planetarium software and a projector. You could project the sky on to your paper to figure out the spacing. This will also allow you to go back in time or even pause time to get your drawings the way you would like. Stellarium is an excellent free planetarium. http://www.stellarium.org/

Yup, has to be Mars. From Hamburg, at 2am, Mars is 30 degees above the horizon, only 10 degrees away from South.

Download Stellarium and you can simulate the night sky for any place and time, to see this yourself.

Constellations used to be an important part of mythology (and astrology), and every culture made up their own figures and boundaries. In the great open-source astronomy Stellarium you can view the night sky with different variations of 'sky lore' superimposed on it.

In modern astronomy, constellations only really serve as a crude way to designate a certain patch of they sky. The International Astronomical Union (IAU) has standardised the 88 constellations, and you can see the official list here: http://www.iau.org/public/themes/constellations/

The list includes the official name and abbreviation of each of the constellations, and a map of its border and connecting lines, and the names and designations of the brightest stars in each. Together, these 88 constellations span the entire sky.

No problem, hope you enjoy it! The computerized version is nice, but you can get much the same effect by just learning the night sky instead- once you have a general idea of where something is in a given constellation, you can scan the sky with the scope to find it.

Planets are easy simply because every planet in the sky (except Uranus and Neptune) is easily distinguishable if you know where to look- i.e. Jupiter is much brighter than even Sirius, the brightest star in our night sky.

For help learning the night sky, I highly recommend the program Stellarium, which shows you the night sky and positions of the planets at any time of night for any location.

Not sure where they're getting the dissm variable from, but the language is prolog.

atan() (arctan) is the mathematical inverse of tan(). In prolog it can take two arguments, being the Y and X values. According to this it is used to convert between rectangular and polar co-ordinate systems.

That's about as much as I can help with this one sorry.

At 3.5 you are better off trying to instill curiosity, I'd start off by teaching them simple things like that the sun is a star, it is so bright because it is so close compared to the stars in the night sky. Things like that will start to push them to wonder about the universe and once they are curious, well, that's where astronomy does the rest of the work.

This book is usually what I hand to family/friends if they express an interest in astronomy or astrophysics: https://www.amazon.com/Universe-DK/dp/1465499954

It would be an excellent resource for your children, the images will definitely draw them in and then as they get just a bit older (even before the star charts in the book expire) you will be able to read to them from it and give them an excellent base of understanding for the universe they live in. The book tries to talk about all the topics linked to astronomy - from the Big Bang to the Theory of Relativity, from the larger asteroids that inhabit our solar system to the planets and their moons, and from elementary particles to the superstructures that form the latticework we know as the our observable universe.

These "dark lanes" are actually thick streaks of dust and gas far in front of the background nebula lit by the nebula's star.

I discovered this in Cosmic Clouds 3D. This book has 3D glasses that show some pictures in 3D. The Trifid Nebula is one of the cooler 3D pictures because it reveals what the "dark lanes" actually are.

I’m on a Cosmology Master course (although more focused towards HEP). For an introductory level in several aspects of Astrophysics (position astronomy, Solar System, galaxies, a brief intro to Cosmology...) I would recommend you this book I used the last year of my degree for the Astrophysics lectures. It may not be the best in every topic, but it can work as a guide.

If you are more interested in Cosmology, I can tell you about more advanced books, but I think that’s not what you may be looking for.

P.S.: I also did that Data-driven Astronomy course on coursera while doing my Final Degree Project basically to get some programming skills, I totally agree with your opinion wrt the Astronomy content

A wonderful but little-known book that looks at the details of a two-dimensional world is A. K. Dewdney's The Planiverse.

I use Stellarium, pretty good features for a free experience. You can use your hands to manipulate the UI or simply point your phone up at the sky and use it as a guide. You can see realtime satellite flybys, but I use a different app (ISS Detector) to notify me of those and Iridium flares, which are sadly gone forever now.

https://play.google.com/store/apps/details?id=com.noctuasoftware.stellarium&hl=en_US

https://play.google.com/store/apps/details?id=com.runar.issdetector&hl=en_US

If you want to learn the mathematics then I would recommend Ellipsoidal figures of equilibrium by Subrahmanyan Chandrasekhar.

What you might want is The Exoplanet Handbook which is up to date to about 2018 but is full of what we currently know from observation and how we make observations. It is a technical book rather than a casual read. The reason I say this book is because you have not been specific about what aspects of exoplanetary science you are interested in and this book covers about as wide of a range as I can think of.

"Predictable" events like conjunctions, eclipses and meteor showers can be found in my app Nightshift (with push notifications if you like). I'm not aware of any apps providing updates about events published on Astronomer's Telegram or similar services.

Try to find a copy of Early Greek Astronomy to Aristotle by D.R. Dicks.

As far as I know, Pythagoras proposed a spherical Earth based on the ancient Greek idea of a perfect shape, not physical evidence. Eratosthenes was the first to estimate the circumference of the Earth.

Soooo a couple considerations:

Good news! Its Milky Way season and the core is visible from the Northern Hemisphere.

Bad news is you don't live in the western US and have access to large areas of dark sky.

Because you're in LA and the Milky Way is visible to your southeast horizon, I'm guessing the best chance to see it well will be going to the coast near a smaller town like Franklin, LA. You'll be looking SE over the water and the light pollution will be behind you.

Now, the real trick is dedication. You need to get away from any stray lights, put away any screens, and sit under the sky for no less than 30 mins while your eyes dark adapt. Then, you should have a nice view of our galaxy.

If you want optics go for a low power bino or even really wide angle "constellation viewers" like these.

If you want a telescope just get an 8" dob. Nothing with an aluminum tripod.

Good luck!

Celestron Skymaster 15x70 Trust me.

These are very portable. I have them in 25x70 which are physically the same size and I hand hold use them to find stuff all the time. 15x70 will give you nice balance of wide field of view and detail.

Which of these 2 would you recommend for someone wanting to start out and why?

I’m thinking the SW because it’s a dob and it’s easier to set up and likely has better optics? The person would be using with an iPhone adapter.

Probably not astrophotography at this time so wouldn’t need EQ.

https://smile.amazon.co.uk/dp/B087QF46HP/ref=cm_sw_r_cp_api_i_dl_H2XR0Q5GDPZVQKTJSVB9

Or

https://www.rothervalleyoptics.co.uk/skywatcher-heritage-130p-flextube-dobsonian-telescope.html

download each months sky map here:

https://www.skymaps.com/downloads.html

on android, free and ad free google sky map is a great start:

https://play.google.com/store/apps/details?id=com.google.android.stardroid&gl=us

Time flows more slowly under heavier gravity than lighter gravity.

You can play with gravitational time dilation using Omni's gravitational time calculator Scroll down to read the directions.

You'd need the formula for relativistic kinetic energy, or a calculator.

Depends on the mass. Let's say a black hole of 10 solar masses or 2e31 kg. The calculator gives me 10944702724735116729816548663348651093115415 MJ.

Thanks for the answers.

So this image of earth in the dark with lights isn't realistic?-

https://www.shutterstock.com/video/clip-10819937-earth-1003-dark-side-city-lights-visible

> Yes, I meant "bowling-ball-radius black hole".

Radius for a black hole is misleading. It is more useful to think in terms of mass.

A black hole with the same radius like a bowling ball (10.85 cm) would have a mass 12x larger than Earth's. It would be about as massive as a big planet.

https://www.omnicalculator.com/physics/schwarzschild-radius

The Sun would oppose very little resistance to the black hole. What really matters then is how fast the BH would be coming in. If it's moving fast enough, it would go right through, pretty quickly, and probably not cause a lot of disturbance.

If it's coming in slowly, and especially if it passes by the large planets in just the wrong way to slow it down even further, it may get captured inside the Sun, after doing a bit of back and forth. It will eventually consume the Sun, but it would take a pretty long time.

I am unable to estimate the time scale it would take it to consume the Sun.

Here is a black hole calculator.

Type in 1 sun mass and the Schwarzchild radius is 1.8 miles. Type in 1 earth mass and the Schwarzchild radius is 0.0000055 miles (.349 inches) across. Of course, the Sun and Earth don't have enough mass to form black holes naturally, but this calculator tells their theoretical size if they did form. Their escape velocity would be the speed of light. Squeeze matter into a small enough ball and its escape velocity is the speed of light.

Regarding the orbital stability, you can check it out by yourself with the awesome (and dangerously addictive!) Super Planet Crash, an online game designed by astronomer/data scientist Stefano Meschiari:

http://www.stefanom.org/spc/

> So we would still see a dim band of light

There probably wouldn't be a band across the sky like we see because elliptical galaxies aren't flat like spirals are. More of a roundish glowing area toward the center. You can explore other galaxies in Space Engine if you want to see for yourself.

It would look very much like that to the eye, but not that bright or colorful. Space Engine allows you to view the galaxy or other galaxies from any angle and gives somewhat more realistic renderings, if you want to try that.

Thanks a lot, I will dream a lot with Space Engine. I think that I was looking for.

btw the last version is not free or I didn't find it but the previous are. http://spaceengine.org/download/spaceengine/

Are you looking for 2D or 3D examples? Or are you asking what are good proportions for illustrative purpuses?

I used the orbital calculator at https://www.omnicalculator.com/physics/orbital-period

Semi-major axis (between two objects): 383,855 miles

Mass of first body: 1 earth

Mass of second body: .75 (You said 3X size of Moon. Moon is 1/4 Earth radius, so I did 3/4 mass of earth.)

Orbit is 20 days and 18 hours.

Change second body mass to .50 and orbit becomes 22 days, 9 hours.

Change second body mass to .25 and orbit becomes 24 days, 13 hours.

Tides would be very high.

Past Moon - Earth tidal interaction tidally locked Moon to Earth and Earth rotation is slowing down.

Large second planet might make planets tidally locked with each other.

Saturn's gravity is pulling its rings into the planet.

If you blew up the Moon into a ring, Earth's gravity could pull the debris into Earth.

Good luck,

Chris Rippel

https://mashable.com/feature/faster-than-light-space-interstellar-travel/

The biggest hazard of faster than light travel is the differences in time between the traveler and those back on Earth.

Right now, for example, I am rewatching Voyager. The ship is on a 70,000 light year trip that may take them 70 years to get back to Earth. The crew act like their families on Earth will be only as old as they are when they get back. According to the online Omni space travel calculator (https://www.omnicalculator.com/physics/space-travel), traveling 70 years at only light speed equals 4,757,743,511,350,649 years on Earth. The Sun will be a white dwarf by the time they get back.

For a realistic treatment of faster than light travel, read The Forever War by Joe Haldeman.

Happy trails to you,

Chris Rippel

MIT is a well-respected school and they provide an introduction to astronomy course.

https://ocw.mit.edu/courses/physics/8-282j-introduction-to-astronomy-spring-2006/

By searching "astronomy mooc" (without quotes) brought me several links including this aggregate. FYI, mooc stands for massive open online courses.

https://www.mooc-list.com/tags/astronomy

Or, y'know, could just borrow a star atlas from the local library and go out on a clear night.

http://www.scholarpedia.org/article/Hawking_radiation#:~:text=Hawking%20radiation%20is%20the%20thermal,inside%20the%20black%20hole%20horizon.

The BH will radiate pairs of photons and they are entangled with one having a positive energy outside the horizon and taking the BH's mass with it and one with a negative energy forever trapped inside retaining its mass, until slowly, photon by photon it's stripped of its mass. 100's of billions of years slow.

Edit: changed "charge" to "energy"

Download a free program called Celestia. This is an astronomy program, but it lets you move to anywhere inside the galaxy. So, if the alignment is possible you should be able to orient the camera to it. One note, it will take you a day or so of playing with the program to learn it well. The key for you is to turn on constellation lines. https://www.youtube.com/watch?v=N7yePKJlhgw (Old vid but shows the basics.) https://celestia.space/ (Home Page)

Since ancient history, mankind has grouped the stars together in 'constellations'. A constellation is a group of stars that, with some fantasy, can be seen to belong together. And we added mythological significance to these groups, making them signify 'the large bear', 'the hunter' and things like that.

Although their position and orientation on the night sky changes with the hour and the season, the shapes of these constellations are quite easy to recognize once you've practiced just a few times. Easy ones to start with (assuming you're on the Northern hemisphere) would be Orion, Cassiopeia, and the big and small dipper, which also helps you find the north star Polaris.

There are 'flash cards' with constellations to practice, but you can also take a laptop or cellphone outside with a program like 'Stellarium' on it. Stellarium is great for this because you can enable the constellation lines, the constellation outlines, and even constellation 'artwork'. And Stellarium is great because it is open source software, and is freely available for Linux, MacOs and Windows.

http://www.stellarium.org/

If you want to make the most of your telescope, you should learn at least a few constellations, and from that learn where the interesting objects are to point your telescope at. And it can also help to join an astronomy club and join them on stargazing activities.

The very center of the chart is directly overhead. North is at the top and South is at the bottom, but West and East are on the opposite sides you'd think because you're looking up from below, rather than down from above. Or something like that. You can also download Stellarium to help you get acquainted with the night sky.

Capella is a very bright star that would have been to the northeast at that time, but pretty close to the horizon, not 40 degrees up. The constellation Cassiopeia would be at about 52 azimuth 40 elevation at that time, but there aren't any bright stars near it.

So my guess is either it was Capella and it was lower than you remember, or an aircraft.

You can check for yourself by downloading Stellarium.

If Polaris is within 1° of the North Celestial Pole, the part of Sagittarius which constitutes the Chinese South Dipper is between 20°-30° south of the Celestial Equator. You may find it helpful to download Stellarium and take a look for yourself.

There's a button on the bottom bar which shows/hides satellites. Stellarium doesn't show too many of them I don't think, but the one in your image looks pretty bright, so hopefully it's there. You could try this to see more satellites. I'm not the most familiar with Stellarium but there are plenty of tutorials and so on around.

Gotcha. I find a Telrad to be invaluable for star hopping, to the point I've retained one on my computerized GOTO telescope. Other than that downloading a program like Stellarium will help you find Messier Objects and other things to look at in the night sky. Happy hunting!

Sure no problem! First I think it is important to just install it on whatever computer you are using. If you go to this this website you can install Python with the Anaconda distribution. The benefit of this is that you will get specialized code editors and libraries all together, without the hassle of you having to choose and install some yourself. Be sure you install the version meant for you operating system and that you download Python 3 as Python 2 is slowly becoming deprecated.

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Once you have it installed just about any intro to python video series on youtube should be proficient. I also think this website is well organized and would be useful as a reference. However I don't recommend you just trying to go through tutorial exercises step by step. The reason why is because it can become tedious and the information wont stick in a way that will be useful outside of the tutorial. This can lead to you doing 100 tutorials and then as soon as you try to do something else you will be lost.

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What I recommend instead is to think about something you want to program that is simple and then try to do it. For example maybe you want to write a function that will solve the quadratic formula for you or save user input to a file. When you inevitably get stuck google the solution, that is seriously how professional programmers solve most of their bugs. This will be vastly more engaging than just copying the answer in the tutorial and you will often find many solutions to your problem; the "best" of which will usually stick, because you can compare to see why it is the "best".

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Good luck, you can do it i'm rooting for you!

This book.

Look into plasma researcher Eric J. Lerner's <em>The Big Bang Never Happened: A Startling Refutation of the Dominant Theory of the Origin of the Universe</em>, where he not only explains how several of the theory's foundational elements (e.g., dark matter/energy, expanding space) are unfalsifiable and provides plausible alternative explanations for certain observed phenomena including the cosmic microwave background and galaxy redshift, but also identifies its ideological underpinnings, namely the ex nihilo philosphy of the Abrahamic religions.

Looking in the realm of chemistry now. I need to find something safe and measurable. Just as some sort of idea, things like this are for sale:

https://www.amazon.com/Ammonium-Perchlorate-90-Micron-Lb/dp/B015RPXUT0/ref=pd_lpo_2?pd_rd_i=B015RPXUT0&amp;psc=1

A decent pair of binoculars and this book or similar: https://www.amazon.com/Touring-Universe-through-Binoculars-Astronomers/dp/0471513377/ref=pd_lpo_14_t_2/141-9217913-9628549?_encoding=UTF8&amp;pd_rd_i=0471513377&amp;pd_rd_r=13bdb13a-46ec-45c7-9671-ee11230c23bf&amp;pd_rd_w=fRGlz&amp;pd_rd_wg=JHlO7&amp;pf_rd_p=7b36d496-f366-4631-94d3-61b87b52511b&amp;pf_rd_r=5PDEWMG04RF1VMPTZQGQ&amp;psc=1&amp;refRID=5PDEWMG04RF1VMPTZQGQ

I'm not sure of the exact science, but you can take pics of sunspots too! You'll need a small telescope or good pair of binoculars, some solar filter and a camera. Phone might work too

E: DONT DO THIS WITHOUT THE SOLAR FILTER APPLIED CORRECTLY

Does it blink red and green? Aeroplane

Does it move up and down close to the horizon whilst standing on a beach? Ship

Does it look like a star but moves over the nightsky? Satellite

Also this might help. ;)

Hi!

Note that there are 2 distinct stellarium applications for mobile.

First one is Stellarium which was last updated on March 21 2019. This is the free version which I am guessing you are using and doesn't have the updated locations in it.

Second one is Stellarium Plus which was last updated on July 12 2020. This is a 10 USD paid app, which should have NEOWISE in it's database.

My humble opinion is that it is not so user friendly that you have to manually upgrade the desktop application's database and also it is not noted that the free mobile app does not get these database updates.

You could also check out this app. It is called Heavens above and has access to an extensive database of satellites and debris of which we know the orbits. It even shows you where in the sky to look to see satellites flying by. They even indicate the brightness in magnitudes (the common unit for brightness in astronomy) which is negative for very bright ones. The limit of what you can see with naked eye in the darkest areas of the earth is 6 magnitudes. So depending on where you live you might not see these faint satellites. However many satellites are very bright and can be of magnitude 1, 0 and even negative values. (Yes that is correct, the brighter the object the smaller the number).

With this info happy satellite hunting.

The Leonids expect an outburst every 33 years or so., 2001 was at a rate of 1000/hr. The 2034 or so Leonids might be really good (or the moon might be in the way). But as intense as the 1833 no that was a special set of circumstances.

This book does some predictions for the next 50 years (well 36 now it was published in 2006).

>Halley's Comet

Did you miss Neowise last month? Much better than Halley's. We have had several comets far surpass Halley's: Hyakutake, Hale-Bopp, and in the southern hemisphere McNaught. Unfortunately most great comets are not predictable we don't know they are coming till they show up.

As far as other events the solar eclipse of 2024 will be the next great one for North America. There are others coming.

Since you're on a budget, this is a good set of eyepieces to get:

https://www.amazon.com/SVBONY-Telescope-Eyepiece-Accessories-Astronomy/dp/B01MR78I42

The 9mm in that set is a much better eyepiece than the 9mm Plossl that you got with the scope. More eye relief, and a wider apparent field of view (66 degrees vs 52).

That kit works out to be $27.50 per eyepiece, and these eyepieces perform much better than their price suggests.

The 20mm won't give you the widest field of view possible, but it will be wide enough to view most large objects. The rest of the objects will comfortably fit in the 15mm and 9mm fields of view. The 6mm will be useful for planetary and lunar viewing on nights when the atmosphere is steady. The 9mm can also be used for planetary viewing on nights when the atmosphere is more turbulent.

Install one of the many stargazer apps available for your phone e.g. Sky Safari (find equivalent for iPhone). It uses your phone's GPS and the time to figure out and show what you're seeing in the sky. So you can point your phone at the bright star as if you were trying to snap a photo of it and it will tell you what it is. Depending on the accuracy of your GPS + compass it should be pretty obvious, especially if it's Mars.

Hello /u/beckoning_cat,
You can follow /u/phpdevster advice eyes closed (open them to look through the telescope tough).

I also recommend you get the Pocket Sky Atlas to easily orient in the sky. It will certainly outlast your telescope ;)

Binoculars are awesome! You can see a ton with a good pair.

I did a quick search and these look pretty good. https://www.amazon.com/Celestron-71198-Cometron-Binoculars-Black/dp/B00DV6SI3Q/ref=sr_1_4?ie=UTF8&amp;qid=1544048594&amp;sr=8-4&amp;keywords=astronomy+binoculars

Another good one for around $50

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https://smile.amazon.com/Celestron-21023-Cometron-FirstScope-White/dp/B00DV6SBRO/ref=sr_1_fkmr0_1?ie=UTF8&amp;qid=1533479371&amp;sr=8-1-fkmr0&amp;keywords=CELESTRON+-+3%22+COMETRON+FIRSTSCOPE+TELESCOPES+SPECIAL-EDITION

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I recommend Astrophysics for People In a Hurry by Neil DeGrasse Tyson.

The best reference I've ever found for "backyard" astronomy is from Yarker's own Terry Dickinson's book Nightwatch: A Practical Guide to Viewing the Universe.

This book is really good, though it is very math intensive, which makes sense considering it's a textbook.

If she likes musing on the ideals or societies an alien might have, tell her to read some Arthur C Clarke books- he has one with 100 stories in or something - https://www.amazon.co.uk/Collected-Stories-Arthur-C-Clarke/dp/0312878605

Many of them cover random alien cultures - some familiar, some very 'alien' indeed. It's a good read and mostly "hard scifi".

There is no way to answer your grandmother's question - we have no clue if life exists at all (although we're fairly sure it probably does) outside our solar system. As such, it's a case of your guess is as good as mine.

All we can do is look to life on Earth and extrapolate. Aquatic aliens are likely to be larger than land based ones, for example. A planet with low gravity might allow for longer / higher jumping (so perhaps longer legs or something). But other than that, no clues. Nor as to their intents. Again all we can do is look at what intelligent life has done on Earth and extrapolate.

Those answers are not promising when it comes to the question of whether aliens would be innately hostile or not.

She may enjoy the book / film Contact, it deals with this in detail. https://www.youtube.com/watch?v=SRoj3jK37Vc

Also not a teacher, though I just wanted to point out that the widely-used textbook for first year astronomy 'science for non-science majors' courses, The Cosmic Perspective, while pricey, is a great resource on which to base a two semester course. It has more in it than you'll need, so you can pick and choose chapters to expand into classroom content. It's almost entirely word-based to keep math out of it, so you can set the math level to whatever grade you're teaching. It covers human endeavours to observe the universe from ancient times onward, and astronomy from the Solar System to the edge of the observable universe.

I know someone who taught astronomy as a single unit in their grade 9 science class. Though not a full course in itself, if it would help I can ask if they still have their lesson plans and notes for the unit.

No. Binoculars have a much larger collecting area and therefore requires much larger attenuation. You can get an appropriate filter to cut to size for this purpose on Amazon for $30.

https://www.amazon.com/Solar-Filter-Telescopes-Binoculars-Cameras/dp/B00DS7SCBQ

Please do not risk your eyesight over $30.

I like the type of star guide that gives you month by month charts like this one.

I would add that tablet or phone apps are not useful at night. They produce way too much light and make it hard to see at night. If you need help with constellations at night, a planisphere works great. You can buy one for your area online, or download and print one (https://in-the-sky.org/planisphere/).

Also, get a red filtered flashlight, as red light can help you work around your telescope. They're relatively cheap online (https://www.amazon.com/AR-happy-online-Flashlight-Adjustable/dp/B01E5EOFSY). You can also make your own if you can get a hold of red filter gels (usually found at theatre or music stores for stage lighting).

All things considered, I recommend some 10x50 binoculars. If you can find some with a zoom function that would be even better.

Checkout THIS PAIR They will be easier to pack, and you can use them during the day too... You can buy a tripod adapter for binos and he could mount them on a portable camera tripod if he wanted to.

> The Meade Lightbridge Mini 130 or a 4-5" Maksutov might be a better choice for (some) imaging, simply because of the Heritage's open structure and simple focuser.

Is the Meade Mini 130 a better telescope (for the price ?)

> I am not familiar with the telescope prices in France. What does a 127mm Maksutov cost over there? (€359 at Amazon, minimum; Not familiar with telescope stores)

Something like this : https://www.amazon.fr/Orion-9825-Apex-127-mm-Maksutov-Cassegrain/dp/B0000XMRRG ?

The size seems fine (without the tripod), better than the Heritage (but more expensive).

How is it better than the AWB/Heritage ? Sizewise and/or quality wise ?

>Do you have a big/rigid camera tripod?

Do you have insights about how big is a tripod this size (like on the amazon picture ?) once folded ?

Edit : Mixing inches and millimeters had me a bit confused for a moment :)

Edit 2 : The matsukov seem pretty compact. I guess I also need to find some small/foldable tripods/table mount to go with it.

Fundamentals of Astrodynamics (ISBN-13: 978-0-486-60061-1) may be a little older now, but it has a chapter on determining orbits from observations.