Y’all, the article is obviously written for people in the path of totality. You’re not being clever complaining about the cost and hassle of traveling.
My wife works for the NPS and her old coworker invited us to help out with their eclipse event in Ohio. Apparently they’re already prepping to close all the parking lots and are real worried they won’t have enough rangers.
I get migraines or just started too. But never get head aches. Migraines for me just make light too overwhelming to look at but it isn’t pain. It’s almost confusion it causes me.
Had to read the article to find out that they mean 72 “years worth of orbits” happen in 1 earth day. Although unlikely I was hoping that it was orbiting so fast that 1 earth day there would pass 72 earth years to a stationary observer due to time dilation. Not sure how fast it would need to go for that to happen.
Since time and speed are relative, to have 1 Earth day on the star and see 72 years on Earth, it’d simply be a speed multiplier of 72*365.24= 26,296.28 times faster. Our solar system orbits the galactic center at 250km/s or 0.0008c, so ~26k times that puts it at nearly 22c relative to us. So no.
But quite frankly, there must be a way to be a slower observer. Earth’s orbital speed is about 30km/s (0.0001c) so that drops the product way down to 2.6c. And while the Parker Solar Probe holds the record for the fastest man made object at 0.0006c at its closest solar approach, it actually took a lot of energy to slow it down to get it to the sun and stall it’s orbit. Otherwise, it’d just orbit it the same as the Earth. It slides out to a Venusian distance from the sun at apogee and drops to 12km/s, halving the differential requirement to +1.2c. But if everything is relative, how do we even determine where 1c is and know it’s so definitively impossible to reach? I don’t know, I’m starting to have an existential crisis. Maybe time just keeps dilating and simple addition/subtraction doesn’t apply for appreciable values of c so you have to start multiplying in decimals.
Relativistic time dilation is nonlinear, so the time dilation “multiplier” approaches infinity as you approach the speed of light. So you will never need more than 1c to pass any finite amount of time for the observer while only passing a smaller amount of time for the moving object. Using a time dilation calculator, it looks like 1 day inside the moving object to 72 years for the stationary observer works out to roughly 99.9999999% the speed of light (9 nines total). Of course if you take into account earths movement as a “stationary” baseline then it’ll depend on whether you’re moving with or against the fast moving object.
It used to melt my brain too but there’s no need to know “absolutely stationary” since you’re comparing 2 objects. And due to the time dilation, the 1c limit is different depending on the observer, the time dilation will prevent anyone from observing >1c even if one person is going 0.9c relative to another person who is also going 0.9c relative to a stationary observer.
COPUOS operates by consensus, requiring approval of all of its more than 100 member states to move forward on any issue, and thus allowing even a single nation to block action
That’s a shitty way to get anything done. Unanimous approval should only be for really big issues. Otherwise just let it be a majority vote.
There will be millions of applicants for this. They’ll get the cream of the crop for this experiment. If we ever end up actually going to mars then these people will be in every history book.
Do NOT buy a $200 telescope new. You’re going to overpay to get a piece of kit that’s okay at best and unpleasant to use at worst (possibly due to uncomfortable eyepieces, difficulty in actually using the scope with bad alt/az controls, bad ergonomics with the stand, etc).
If you want a cheap scope just to find out if you’ll like amateur astronomy: Go hit some garage sales or a resell app or Craigslist or something, but I particularly recommend garage sales. There’s plenty of these cheap ‘hobby killer’ telescopes that can be had for a fraction of their retail price this way, and the resell value is a little more reflective of what they’re actually worth.
Alternatively: drop about 1/4 of that on some good binoculars. You can absolutely stargaze with binoculars, I actually always bring some when I do public outreach. I’m very fond of 7x50s, because the low magnification (the 7) works really great on open clusters and makes them easier to steer, while also not being so heavy that they wear out your arms after ten minutes. The 50 describes the aperture size, which means that your binoculars will have plenty of light- gathering capacity. The bigger the apertures, the more light they’ll collect, but the heavier and harder to use they’ll be. Plus, their magnification won’t be too far beneath the maximum magnification of a generic retail telescope.
If you want a great starter scope: I’d suggest that you save your money, don’t burn your budget on a crappy retail refractor. I’d also suggest doing one of the two above things to decide if you even like astronomy enough to spend the money on a good scope. If you do like it, and you do want a good starter scope, it’s hard to go wrong with a 6" dobsonian. They’re relatively cheap for what they are, very portable and manageable, and there’s a LOT you can see with them, even in the city, but especially in dark skies. Also, you could probably find some good used ones in your area for a bargain; there’s lots of folks who splurge on telescopes and fall out of love with them, and then just have it sitting in the corner of the garage for years and years. Like I said, garage sales are really great for this.
Btw, don’t get aperture fever and splurge on a double-digit aperture. I did that, but I specifically did it for outreach purposes; if I was getting it strictly for my own use, I’d have a $1500 oversized dust collector because it can be a real PITA to move outside.
I never even thought about garage sales! Is there a way you can test to see if they’re damaged or defective in the middle of the day? I’d hate to purchase a broken one without even knowing it.
Tl;Dr getting focus before you leave isn’t SUPER important. It can be kinda tricky to figure out for newcomers, and you’re better off using your time to assess the action and components of the scope.
Yeah, so, you’re going to want to spend some time on YouTube U learning about how to focus a telescope. It could be trickier with a dobsonian/newtonian because you may need to collimate it (though the smaller the telescope is, the less important that becomes) to see clearly, and someone at a garage sale may or may not be willing to do it for you / trust you to do it. Generally speaking, though, if all the moving parts move like you expect them to and don’t move like you don’t expect them to, the lens or mirrors aren’t obviously damaged or scratched, the eyepieces aren’t obviously damaged or scratched (eyepieces are MUCH more sensitive to any kind of damage than mirrors or lenses in terms of user experience), then you’ve got a winner. It’s hard to think of a situation where a telescope’s parts would be in working order and good condition but somehow be broken in a way that prevents it from achieving focus.
For assessing movement: with a dobsonian in particular, but really any mount, you’ll want it to be very easy (ALMOST but not quite frustratingly easy) to move the telescope so that you can track targets across the sky easily. The telescope, however, shouldn’t move on its own without some force acting on it (i.e. touch, wind, etc). If it’s moving under gravity, then either the balance is off (very possible with a dob, and usually easy to fix too), the friction is off (also an easy fix with a dob), or the mount could be bad if it uses some other kind of altitude-azimuth (left-right-up-down) mount that uses clamps and locking knobs and such. Also, make sure you try adjusting the focuser tube. They stick out and tend to get whacked, and if your focuser tube is busted, you’re SOL. Just check to see that it moves when it should and not when it shouldn’t, and that it goes all the way in and out without falling out; if it doesn’t, check for some little thumbscrews on the focuser. Sometimes, when those are tightened down, they’ll keep the focuser from moving, or let it move way too easy if they’re too loose. If those thumbscrews aren’t the problem, then the focuser is busted and you should give it a pass.
I also highly recommend checking the finder scope- that’s the little buddy telescope that’s attached to the telescope that’s there to do business. They stick out a bit and have a habit of getting damaged. It’s not a huge deal if it’s broken, they can be easily replaced, but you’re going to want to replace it before you head out or you’re going to have a bad time. Lots of people love Telrad finders, I’m an absolute nut for RACIs; beware the little straight-through scopes, though, as they’ll murder your neck when you have to look at something high up.
If you really want to try and look at something (not a bad idea, per se, just not the most effective use of your time. I’m assuming neither you nor the seller will immediately know how to achieve focus with the scope), try to pick something both big and very, very far off. If the moon’s up, try looking at that. If not, try to pick the furthest, biggest thing you can see (big makes it easy, but if it’s too close, you simply will not be able to get focus on it, period) and try to sight it in.
This deserves its own post because I nearly forgot but it’s kinda important:
If you end up buying a reflector telescope from a garage sale, DO NOT CLEAN THE MIRRORS. Unless you can’t see your reflection in them at all, just don’t touch them. You’ll be shocked at how little the dust actually impacts your view, but these mirrors are super crazy easy to permanently mess up. If you must clean them, DO NOT use a rag, DO NOT use compressed air! Use a gentle stream of distilled water to rinse it clean. The big danger here is that you could end up dragging sharp/hard debris across the mirror and cutting some serious gouges into it. This is also true of the eyepieces. Don’t use re-usable rags to clean them. I use lintless cotton eyeglass patches to clean my pieces after fogging them up with my breath (that’s cheap and readily accessible distilled water) once I’m satisfied that they’re free of any large debris. I wipe in one direction, flip it, wipe in another direction, and dispose of it. That’s it. The eyepieces being a little dirty will mess up your view, but a dirty mirror probably won’t. Only clean it if you’re 300% convinced that you must.
Also good advice: try using the telescope at least twice before you go to the event. The moon is probably the easiest, brightest target, and it’s a good place to start with making sure your focus is close to perfect. Once you’ve got the moon, move on to a few slightly more challenging but still easy targets that you should be able to see, even in an urban area, to make sure you understand how to use the scope and put it through some actual use. A pretty easy target would be the first star out from the cup on the handle of the big dipper. Tell me what you see when you find it in the scope. Jupiter is also a pretty easy, rewarding target. The sword of Orion is another bright, easy one. Lastly, Venus is a really easy target and has a little surprise for you when you find it. But two uses is enough to get familiar with your equipment, get familiar with its use, and identify any problems before you actually get out there.
Thanks a lot for all your advice! I looked around Craigslist and ended up finding an astronomy enthusiast who was upgrading his gear and gave me a great deal. I purchased a Sky Watcher Heritage 130 Tabletop Dobsonian, SVBONY SV225 Alt-Azimuth Mount, and a SLIK PRO 700 DX AMT tripod for about $208. The MSRP with tax is easily triple that! The equipment was in great in shape and I could easily see some of the brighter stars in a Bortle 8/9 sky relatively easily. I plan to purchase a couple of light filtering eyepieces for seeing the sun and moon to complete the setup.
Hey, that’s awesome! Great job! It’s going to be real easy to drop a LOT of cash on eyepieces. Don’t. Start on the cheaper side and only move up if you find that the eyepieces are limiting your viewing experience. A lot of people really like the 8-24 mm click-stop zoom pieces for starter eyepieces, though I don’t have any experience with them. If you really want to splurge, buy a wide field of view piece. The full moon will be a deadly laser but doable without a filter. The sun will literally set your eyepiece on fire. I’ve seen it happen. An eyepiece filter will not be enough to protect you or your equipment from the sun. There are filters that will fit over the aperture (the end of the tube) that are basically the same material as solar eclipse glasses, and that’s what you need. They aren’t expensive, last I looked, though, again, I have no experience with them. For a list of possible targets to get some practice, see astroleague’s urban observing program here: www.astroleague.org/urban-observing-program/Note that there’s a separate list of multi-star systems you should be able to split (see at least two distinct stars) in a scope of your size. I’d also recommend using Stellarium; it’s a free app that’s actually free, and it’s absolutely dead useful for learning the night sky and planning/aiding viewing sessions. I use it to help me plan my outreach outings, and I really can’t recommend it enough. Best of luck, I’m really happy for you, and please let me know how it goes!
+1 on binos. They’ve kept me happy because they fit in a backpack or carry-on luggage. I’m deep in light pollution, so viewing is best done with some travel. They have less magnification, but they’re as bright as a much more expensive telescope and there’s a certain value to having two eyes on the night sky.
10x50 is where I landed. Probably the same weight as your 7x50. While yes, the 50(mm) describes the outer objective lens, the key thing is really the lens on the eye side. Divide the aperture by the mag and you find that exit pupil size. 50/10=5mm, which is about the size of a dilated adult eyeball pupil - and they get smaller as you age. I’m guessing you have a Celestron or similar astro bino which has some advantages for this hobby. I am surprised at the ~$40 price tag, so I no longer want to recommend against it. Where I WAS going was that 7x35s would likely give a similar image from a reputable manufacturer while saving a little weight and being more likely to be found at a garage sale. But who could say no to $40 new 7x50s? As long as OP avoids those 20x50 boating binos or 10x25 hunting binos, they’ll be in good shape. My 10x50s are closer to OP’s budget because I opted for Nikon Action Extremes to survive my beach spot, hikes, travel, drops, and any other mishaps alike. Things go bump in the night so rubber coating and waterproofing was worth it to me
I use 7x35s for outreach and they work pretty well. I got my kids the Celestron 10x50s and can’t recommend them enough. They’re really, really great. Not too heavy or bulky, even for kids, but still very capable of enhancing your stargazing experience. They can juuuust about split a Galilean moon, IME; Jupiter will look a little odd, but I haven’t been able to distinctly identify a moon with them.
By split a gallilean moon, do you just mean see up to 4 moons separate from Jupiter? I’m pretty sure I can distinctly see them, at least with elbows on a railing or on some mount. I guess I’ll have to look tonight if it’s clear. I kinda only remember catching 3 at a time and not investigating further. I do have 20/15 vision so I guess that plays a role. Good point to remind me not everyone has my hawk eyes. I don’t catch much color though. Usually too small and washed out. It’ll have slight pink bands at best. I haven’t been able to note a crescent shape for venus, either. But I figure even cheap scopes can show my planets, so it hasn’t been my focus
Yeah, that’s what I mean. I’m impressed! For me, Jupiter looked kinda smeary, like looking at it with an astigmatism, only it wasn’t an astigmatism, it was the moons. As for Venus, I guess you might just need higher magnification to cut through the glare and resolve the crescent. The minimum power I use in my dob is 50x and you can clearly see the crescent at that power.
Alright, seeing the moons was harder than I remember with 10x50 Nikon AE. Handheld, about 80deg up. For a few moments, I could pick them out, but the shakes got too intense to see them again reliably. That’s with decent knowledge of what to expect. My memory is probably based on the one time I actually used my homebuilt parallelogram mount. Or maybe when jupiter was 30deg up and my elbows were on a railing
Hey, it’s cool that you followed up with this! It would make sense that the shaking is too intense for the fine details, especially at that high angle. I feel like I’ve heard of people using image-stabilized binos for stargazing, maybe that could make a difference?
Looking at the prices, my cheap ass would sacrifice some portability and opt for a tripod and a lightly fabricated aluminum or oak stick (read: drill 3 holes) to make a 24-36" offset mounting plank and carry a 5lb counterweight
I’m so looking forward to what JUICE uncovers! Europa has been centre stage and is getting its own dedicated mission, but the more we find out about those outer moons, the more fascinating they get. Ganymede is the largest in the solar system and has its own magnetic field. And Callisto being an ocean world? It wouldn’t surprise me if Ganymede is also.
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