Starship Asterisk*

The APOD from launch day, at the first link, says that "When the robotic Juno spacecraft reaches Jupiter in 2016, it will spend just over a year circling the Solar System's largest planet," but today's APOD says two years.

Why the discrepancy?

Wow. So where does a New Yorker go to see some sky? No gaps anywhere nearby, and all the airports I could fly into are right in the middle of the worst problems.

Maybe a boat? How far would we need to sail?

I don't consider it a matter of faith in the least .. Epistemologically speaking, faith is belief in something without requiring evidence. As I pointed out, my suggestion that the inference of intelligent life elsewhere is reasonable is based on specific examples of evidence. It is impossible to in...

Chris Peterson wrote: I don't consider it a matter of faith in the least..

Not "in the least"? Really? Is this because you because you find your point airtight, or because you just happen to dislike the word "faith"?

Good point on technological vs intelligent, Evermore (and Chris)!

I think it is very reasonable to assume that there have been a very large number of intelligent life forms in the Universe You're usually precise in your word choice, Chris. It's "reasonable" to assume that if there are a few instances in an enormous field, there may be a lot. In fact, th...

From last week's NY Times by University of Rochester astobiologist Adam Frank (who recently co-authored this paper ): the odds that we are not the first technological civilization are actually high. Specifically, unless the probability for evolving a civilization on a habitable-zone planet is less ...

First link is dead, fwiw.

What finally worked for me is a bit of a "duh", but it took me a while to figure it out so I'll share: don't worry about the image for a moment. Just make cross-eyes. Then look at the image. Voilà .

Can someone please post the reversed images? Perhaps to Imgur, or other free easy image upload service?

Nitpicker wrote:
I don't think you can get any visual sense of how close Mercury is to the Sun from watching the video (other than that it is closer than Earth).

Oh, absolutely! But that doesn't mean the eye doesn't try....

Thanks, interesting! From the video, it seems way closer than that. Telescope effect, angular effect, etc. My favorite part was the last few seconds, as Mercury completed its transit and kept going laterally against the background of the corona. I was sorry it wasn't illuminated from this direction,...

Hmm, I don't know about that one, Chris. It's intrinsically hard to argue about a subjective perception, especially with the sun/moon illusion involved....plus, as you say, the brightness issue interfering with any precise perception of size. But we do have a pretty sharp sense of the moon's apparen...

SPF 2000 ! ... Wow, How big is the Sun in the sky on Mercury ? Here is solar size as seen from every planet: http://www.astronoo.com/en/children/sun-apparent-size.html I wonder if we'd feel not just surprise and marvel but also a deep revulsion at its unnaturally small size viewed from an outer pla...

My favorite part was the last few seconds, as Mercury completed its transit and kept going laterally against the background of the corona. I was sorry it wasn't illuminated from this direction, so we could see it recede and disappear behind the sun. I'd have liked a visceral sense of its orbital dis...

The Sun isn't much of a threat to our eyes at all. ....and yet if you go 1,000,000,000 miles further out, to where the sun is only 1% of its earthly brightness, you still can't safely stare at it. Hence my perplexity. It's like saying a certain acid isn't particularly caustic, but you shouldn't get...

Just intuitively, I'd have figured from that that the sun, at our distance, would present a viciously perilous threat to the eyes; that humans would have evolved a downward-looking face and we'd all be nocturnal. Etc.

Every time I see the sun depicted from distant planets/objects, it makes me wonder how far away a human would need to go before he could safely stare at the sun. Any ideas? That sort of depends upon how long one intends to stare directly at the Sun but for someone with excellent vision it would pro...

Every time I see the sun depicted from distant planets/objects, it makes me wonder how far away a human would need to go before he could safely stare at the sun. Any ideas?

There's apparently a great detailed view of this on the April 9th episode of the podcast, Skeptics Guide to the Universe.

The Economist link offers by far the most detail, fwiw. ... the coverage from The Economist ... A new plan to send spacecraft to the stars: replace rockets with lasers The Economist | 2016 Apr 12 Stephen Hawking and a Russian Billionaire Want to Build an Interstellar Starship Gizmodo | 2016 Apr 12 H...

I'm a big Jar Jar Binks fan.....

Good idea, but I worry that the eyeballs and brows might put him just over-weight.

Indeed! I love how the EASY part is to manufacture thousands of spacecrafts, each with the weight of a paper clip and carrying a computer, a camera, a laser communication system, and a plutonium engine. I'm done complaining about my non-ownership of a jetpack. Between this and the craft beer boon, I...

No. The 100GW laser array will fire for only ten minutes. It'd be impractical to direct millions of lasers at targets this small, fast, and distant for much longer. Note that this isn't Starwisp, it's a newly-announced program, Starshot. It's so new that the Wikiepdia article is still under-develope...

Thanks, Neufer. So three days to reach Voyager's position. Pretty incredible!