Starship Asterisk*

Sun-Earth LaGrange L2 is a LONG way from Saturn's orbit, eve when it is outwards. Is that realistic, neufer?

Thanks, Chris. Nasa's Dragonfly mission will land a flying rover on Titan in 2036. By then, UN271 will be halfway to the orbital distance of Neptune, and well out of the ecliptic. Would you think that anything could be 'piggy-backed' onto the Dragonfly carrier that could be sent towards the comet? J...

Just been back to the Nasa page and fiddled with the controls to look from the Ecliptic. That shows that the orbit of 2014 UN271 is almost at right angles to that plane, so it comes from way, way outside! Has the orbit been observed for long enough to tell if it is one of the Sun's children or anoth...

I got excited when I read a short piece from New Scientist about this "huge and previously unknown object entering our solar system that will reach the orbit of Saturn in 2031"! Wanting to know more, I searched and found this from Nasa: https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=54161348;orb=1...

Further, in answer to Shaleshs, stellar jets may be intermittent, and/or assymmetric.
See the Wiki entry: https://en.wikipedia.org/wiki/Astrophys ... 87_jet.jpg
And this Hubble pic: http://www.eg.bucknell.edu/~mead/HomePa ... Disk3.html

John

What ever happened to "craterchains", the apocalyptic contributor who argued they were evidence of prehistoric interplanetary warfare?
He would have loved this!

Tadpole, The gas giants of the Solar System may have developed much closer to the Sun than they are now, and we have evidence of extra solar gas giants that orbit as close, or closer, to their suns than the Earth. Some event caused the rearrangement of Solar orbits that we see today, so there is no ...

XgeoX, there are other designs for extraterrestrial wheels - for instance the wire mesh ones on the Apollo Lunar Rover: https://www.pinterest.co.uk/pin/64528207130752446/

JOhn

It's interesting that the shape of a Mars Rover seems to converge, whoever the designers!
I presume that's a thermonuclear power generator at the back, like Curiosity's?
And the wheels are very similar. 'Borrowed' ideas maybe, but they decided on the same design.

AHEM! "no known geological mechanism"??? Chris, see: https://www.theguardian.com/environment/2019/aug/25/massive-pumice-raft-spotted-in-the-pacific-could-help-replenish-great-barrier-reef Underwater eruptions produce pumice, lava so full of gas that when solidified, it floats. How long it...

AHEM! "no known geological mechanism"??? Chris, see: https://www.theguardian.com/environment/2019/aug/25/massive-pumice-raft-spotted-in-the-pacific-could-help-replenish-great-barrier-reef Underwater eruptions produce pumice, lava so full of gas that when solidified, it floats. How long it ...

"wHimsy", neufer, wiv an 'H', and no 'e'! And the Lord Peter, however much Sayers gave him the manners and appearance of an upper-class 'silly ass' (a donkey-type ass!), or how he has been portrayed by actors, has the incisive, intelligent and dare I say, scientific mind, that made him a t...

Light-hearted? "When I hear the word 'Culture' I reach for my revolver!"

The beauty of science is overwhelming - there is no need to embellish and decorate it with whimsy!

Apod, are you purposely trying to be annoying, after our criticism of your 'Face on Jupiter' pic, yesterday? A 'Flower' moon? The moon has no flora, never has, never will. A 'Super' moon? That does NOT "appear a bit larger and brighter than the average full moon" - it is 7% wider than an a...

I agree with Ann! If Apods aren't greeted with sighs of aesthetic delight, they get geven a name. Anything "mcanyface" is so lame and hackneyed that you should be ashamed of yourselves. This picture adds NOTHING to scientific knowledge!
John

Of course, stellar systems are mainly empty space, too! An alien spacecraft visiting the Sun would have to conduct a very careful survey to determine that we had any planets, and finding the terrestrial ones wouldn't be easy. (The paper estimates 50 interstellar objects inside a 50 AU radius sphere...

Of course, stellar systems are mainly empty space, too! An alien spacecraft visiting the Sun would have to conduct a very careful survey to determine that we had any planets, and finding the terrestrial ones wouldn't be easy. (The paper estimates 50 interstellar objects inside a 50 AU radius sphere...

"Flying blindly through the Galaxy" Like Oumuamua, the first extrasolar object detected. But we may already have another one, 2I/Borisov (https://www.nature.com/articles/d41586-019-03530-3 ) and there could be as many as 50 interstellar objects within the Earths orbit ( https://link.spring...

Thank you, Chris, for the words about "sterile" globular clusters - "learn something every day" - Aristotle? For Orin, I looked for online animations of the movement of a cluster, but many seem to show an axial rotation, or else what they show is a simulated 'fly-by' of a relativ...

Thank you Ann, always interesting! And stars 0.1LY apart, on average? You don't tell us what the SD is, but that sounds awful close, even if it is 6^11miles (10^11kilometers)! If there are planets around those stars,and there must be, and there is life on those planets, as there may be, or has been,...

Quote this APOD description, "Galactic beasts such as expanding supernova remnants, hot winds from newly formed stars, unusually strong and colliding magnetic fields, and a central supermassive black hole are all battling in a space only 1000 light years across." I've asked this before, an...

Chris,
Then I misunderstand the chart from the UK Hydrographic Office!
Appears to show a partial eclipse east of the Californian coast and west of Java. What do the contours mean, then?

Totally misses Europe, of course!
John

Ummmmmmmmmm? " The next total lunar eclipse will occur on Wednesday"?
Total only over most of the Pacific, Australia and New Zealand!

http://astro.ukho.gov.uk/eclipse/1112021/L2021May26.pdf
JOhn

Thank you for your seminar, Ann! I am that tiny bit wiser!

Every British schoolboy is, or used to be, familiar with the story of the Dam Busters, 617 Squadron of WW2, that used Prof.Barnes Wallace's work to 'skip' bombs over torpedo nets and onto the inner wall of several dams, catastrophically breaching them. The "Bouncing Bombs" were cylinders a...