Astrophysics and Cosmology - Discuss the Universe here

[GeorgieForPresident2216]

Hey, Cam!  Welcome back.


http://www.youtube.com/watch?v=xZzEzDkeHzI

[zeebo]

Hey, Cam!  Welcome back.

Yes welcome back Cam

.. and Philae Lander. 

[Camazotz Automat]

Hey, Cam!  Welcome back.

Yes welcome back Cam

.. and Philae Lander. 

I rationalized the posting of a comment by using internal bargaining: "I will return from voluntary exile if a comet lander awakens. Hey, now, what's this? Philae phones home? Better log in."

[lonevoice]

Comet lander Philae receives solar energy and wakes up.

So cool!  I hope Matt Taylor is knocking back a few brews while wearing his lucky shirt. 

[Camazotz Automat]

So cool!  I hope Matt Taylor is knocking back a few brews while wearing his lucky shirt. 

Or even more than a few. 

The probe headed to Pluto blows my mind quite enough as it is; the Voyagers continue to dramatically amaze me; the Mars rovers are beyond cool, et al ... but to successfully land a probe onto a comet and despite a failed harpooning (that's what she said) Philae wakes up and transmits data.... it is beyond my meager brain gear to process! heh.

It (and all missions) certainly puts things into a broader and more positive perspective and helps me get out of my head for a little while.

Bless the lucky shirt.

[lonevoice]

Or even more than a few. 

As long as he doesn't drink and drive.   

The probe headed to Pluto blows my mind quite enough as it is, the Voyagers continue to dramatically amaze me, the Mars rovers, et al ... but to successfully land a probe onto a comet and despite a failed harpooning (that's what she said) Philae wakes up and transmits data.... it is beyond my meager brain gear to process! heh.

It (and all missions) certainly puts things into a broader and more positive perspective and helps me get out of my head for a little while.

Bless the lucky shirt.

It puts so much into perspective.  I remember an article that compared it to a fly landing on a speeding bullet.   I hope Matt continues to enjoy and express himself through his sartorial choices. 

[zeebo]

Newest champion for farthest galaxy ever spotted - 13.1 billion light-years from Earth.  We see it as it was 670 million years after the big bang ... not long after the first stars turned on.



http://news.nationalgeographic.com/2015/05/150506-most-distant-galaxy-astronomy-space/

[Camazotz Automat]

Newest champion for farthest galaxy ever spotted - 13.1 billion light-years from Earth.  We see it as it was 670 million years after the big bang ... not long after the first stars turned on.



http://news.nationalgeographic.com/2015/05/150506-most-distant-galaxy-astronomy-space/

OK, kids. Everybody into the station wagon! We're going to drive out and get a closer look at this thing. Your mother packed the cooler with sandwiches and sodas.

[GeorgieForPresident2216]

OK, kids. Everybody into the station wagon! We're going to drive out and get a closer look at this thing. Your mother packed the cooler with sandwiches and sodas.

Yay!  I hope there's Vanilla Coke.

[Camazotz Automat]

Yay!  I hope there's Vanilla Coke.

There is plenty of Vanilla Coke. But do me a favor, will ya, sport?  PLEASE ... do not keep asking "Are we there yet?  Are we there yet?" when we haven't even made it a billion light years out. If you get bored, it's not going to kill you to play some AUTO BINGO with your sister.

[area51drone]

Where is agent orange when we need him to answer some of the biggest questions in our universe?

[zeebo]

Where is agent orange when we need him to answer some of the biggest questions in our universe?

Maybe busy in some underground lab, tryin' to catch himself a cup o' neutrinos or such.

[GeorgieForPresident2216]

There is plenty of Vanilla Coke. But do me a favor, will ya, sport?  PLEASE ... do not keep asking "Are we there yet?  Are we there yet?" when we haven't even made it a billion light years out. If you get bored, it's not going to kill you to play some AUTO BINGO with your sister.

Okay.  I'll be good.  Please, please don't turn the car around like last time.  And can we have some ice cream?

[zeebo]

Just came across this article from a few years ago.  It proposes a way of propulsion similar to solar sails, but instead using electric fields, which eminate from "long, lightweight wires that extend outward like umbrella stays".



E-sails differ from photon solar sails in that they catch the solar wind rather than sunlight ... The solar wind is a high-speed but extremely tenuous stream of electrically charged gasesâ€"ionized hydrogen and heliumâ€"that flow outward from the sun. And although that ion stream exerts a dynamic pressure that is some 5,000 times smaller than that produced by solar photons, each charged wire produces a cylindrical field that can be as large as 100 meters in diameter, which makes for an effective sail area that is as much as a million times bigger. ...That's the trick behind the e-sail's efficiency ... When you switch from physical to electric sails, you lose a pressure factor of 5,000 but gain an area factor of a million.

Next time AO drops by would like to hear his thoughts on this idea.

http://www.scientificamerican.com/article/spacecraft-solar-sail/

[Agent : Orange]

Hah.
"That's funny... Every time the Philae lander is around Cam is not. And every time Cam's around the Philae lander is nowhere to be seen...
wait a sec... maybe Cam IS the Philae lander!!
Oh, Agent : Orange, that is the dumbest idea I've ever thought of."
And somewhere Clark Kent pushes his glasses up to the bridge of his nose and winks at a camera. 

Anyway was just passing through and noticed the previous post, very interesting Zeebo! Honestly I've never run into the idea of an E-sail before but it seems like it could be plausible. The wires have to be very long, because part of the trick here is to get the electric field from the wire to drop off very slowly. From Maxwells equations you can show that an infinitely long wire will produce an electric field that will drop off as 1/r instead of the usual 1/r^2 drop off you get from a point charge (as an example the solution is given here http://faculty.wwu.edu/vawter/PhysicsNet/Topics/ElectricForce/LineChargeDer.html). Of course an infinitely long line charge is unrealistic but the upshot of this argument is that the effective cross-section of the wires will increase with their length. Just changing the geometry from a point to a line produces a much stronger electric field that drops off more slowly. Not an exact argument at all because it ignores what happens at the ends of the wires where there will be large fringe fields but for all intents and purposes I would not be surprised that you could get an effective (but still small) boost from this kind of method.
If you wanted to make an even bigger effect - but one which is totally unrealistic - you could use a solid charged sail. Then the electric field will drop off even more slowly near the surface of the disk (ie http://www.physics.udel.edu/~watson/phys208/exercises/kevan/efield1.html) and you'd get an even bigger boost. Of course any fast moving grain of dust will punch a hole in your charged disk and ruin it so the long wires seem more plausible.

You will want to make sure you launch your E-sail during or near a solar maximum as well to optimize the amount of plasma the Sun will barf at you. And, why not double your fun with a two stage E-sail and solar sail further up along the line? When you're near the Sun you can have both deployed, then once you're up to speed eject them at the edge of the solar system to cut down your mass and get even more of a boost. I've not kept up with the current state of the Art's new upcoming show (so I'm sorry if it's a painful topic if something has gone wrong with it since I've been gone) but I hope Art does a whole upcoming show on potential unconventional propulsion systems for space-craft and how they could be used. Would be very interesting.

Incidentally by analogy you should get a stronger force of gravity near a long string of mass than you would from a point mass as well, part of what would make a cosmic string so interesting.

Hope you are all doing well!

And Cam - please keep sending science data back from comet 67P. I'm glad the Sun once again shines on you and that you were able to efficiently recharge your batteries. Your secret is safe with me.

[Agent : Orange]

Where is agent orange when we need him to answer some of the biggest questions in our universe?

Off trying to answer smaller and more manageable questions.

Just dropped in on a whim today but glad that I did. Hope you guys are all doing well and you had a nice July 4.

I've been working hard since the beginning of the year and running stealthy and quiet ever since. Have kept my head down and had some serious results work out in my favor. So the summer has turned out to be very busy (in a positive way) with some unexpected travel and conferences come up on my radar.

Anyway this story came up as a press release yesterday:
"Biggest explosions in the Universe powered by strongest magnets"
http://www.eso.org/public/news/eso1527/
which made my antennae perk up. Art needs to have an expert on magnetars come on his show and discuss these objects with him. They are not as nearly well-known as black holes but are in many ways more interesting - at least to me anyway

[WOTR]

I've not kept up with the current state of the Art's new upcoming show (so I'm sorry if it's a painful topic if something has gone wrong with it since I've been gone) but I hope Art does a whole upcoming show on potential unconventional propulsion systems for space-craft and how they could be used. Would be very interesting.

Right then... Art is still coming back, and the show immediately after his will be hosted by none other than Richard C Hoagland.  You are hereby required to call in during one of his shows to serve as his science adviser.

[Camazotz Automat]

Hah.
"That's funny... Every time the Philae lander is around Cam is not. And every time Cam's around the Philae lander is nowhere to be seen...
wait a sec... maybe Cam IS the Philae lander!!
Oh, Agent : Orange, that is the dumbest idea I've ever thought of."
And somewhere Clark Kent pushes his glasses up to the bridge of his nose and winks at a camera. 

You cannot prove this.

Now, if you will excuse me, I need to go recharge my power supply grab some breakfast.

(servo clicks)

[GeorgieForPresident2216]

You cannot prove this.

Now, if you will excuse me, I need to go recharge my power supply grab some breakfast.

(servo clicks)

Does this mean our road trip to the most distant observed galaxy is off?  I just spent all day shopping for a bathing suit that wouldn't clash with my luggage.

[chefist]

i've never heard of "magnatars"...very interesting!...not to be confused with "magnatards", slow spinning neutron stars...

[zeebo]

You will want to make sure you launch your E-sail during or near a solar maximum as well to optimize the amount of plasma the Sun will barf at you....

Good advice AO!  Thanks for the response.   

[zeebo]

i've never heard of "magnatars"...very interesting!...not to be confused with "magnatards", slow spinning neutron stars...

Don't forget about Magnemite.

[Camazotz Automat]

Pluto probe officially begins flyby.

https://www.scientificamerican.com/article/pluto-flyby-begins-nasa-probe-enters-encounter-phase/

Does this mean our road trip to the most distant observed galaxy is off?  I just spent all day shopping for a bathing suit that wouldn't clash with my luggage.

Go ask your mother, son. Your father is busy looking at naked raw scientific photos of Pluto on the internet.

° ° °

Don't forget about Magnemite.

You're a raaaaaaaaaaaaaaving anti-Magnemite!

[zeebo]

You're a raaaaaaaaaaaaaaving anti-Magnemite!

It's true, I prefer Magneton.

[Camazotz Automat]

Pluto, taken from 5.4 million kilometers this last Thursday.

Imagine the clarity we will witness when we are only 8,000 miles out instead of 3,355,404 miles out.

As Roswells, Art would say,

This is so fucking exciting!



I've already got a snail mail letter at the ready, addressed to NASA, demanding (or begging) they send me an official Pluto Poster featuring the latest data.

It's my right as a civilian of these United States of America.

I did, of course, pose as a six-year-old boy, aspiring to be an astrophysicist.

Also... I wrote the letter with a purple "Pluto" crayon. (More effective, emotionally. Hell, maybe they will send some Mars Rover swag.)

I will be dropping the letter in the mail just as New Horizons is moving away from Pluto.

[GeorgieForPresident2216]

Pluto, taken from 5.4 million kilometers this last Thursday.

Imagine the clarity we will witness when we are only 8,000 miles out instead of 3,355,404 miles out.

As Roswells, Art would say,

This is so fucking exciting!



I've already got a snail mail letter at the ready, addressed to NASA, demanding (or begging) they send me an official Pluto Poster featuring the latest data.

It's my right as a civilian of these United States of America.

I did, of course, pose as a six-year-old boy, aspiring to be an astrophysicist.

Also... I wrote the letter with a purple "Pluto" crayon. (More effective, emotionally. Hell, maybe they will send some Mars Rover swag.)

I will be dropping the letter in the mail just as New Horizons is moving away from Pluto.

Genius!

[b_dubb]

Um this sounds ominous

http://www.upi.com/Business_News/Security-Industry/2015/07/10/US-tests-B61-12-nuclear-gravity-bomb/7211436542217/

[Camazotz Automat]

Genius!

I may provide updates on my shameless deception.

[GeorgieForPresident2216]

Um this sounds ominous

http://www.upi.com/Business_News/Security-Industry/2015/07/10/US-tests-B61-12-nuclear-gravity-bomb/7211436542217/

It sounds impressive, but doing some checking 'gravity bomb' just means it's unguided (not smart), although this version is equiped with a 'guided tail kit' to increase accuracy from over 100m down to 30m, allowing for reduced yield.  It's essentially an upgrade of an old class of tactical & strategic nuclear bombs, allowing several older designs to be consolidated into one and intended to reduce the total stockpile.


http://fas.org/programs/ssp/nukes/publications1/Brief2014_PREPCOM2.pdf

[b_dubb]

It sounds impressive, but doing some checking 'gravity bomb' just means it's unguided (not smart), although this version is equiped with a 'guided tail kit' to increase accuracy from over 100m down to 30m, allowing for reduced yield.  It's essentially an upgrade of an old class of tactical & strategic nuclear bombs, allowing several older designs to be consolidated into one and intended to reduce the total stockpile.


http://fas.org/programs/ssp/nukes/publications1/Brief2014_PREPCOM2.pdf

Read through a Wiki entry on this class of weapon and yeah it's just a nuke. The article headline made it sound like it was some kind of gravity weapon. Which sounds like something from a sci if story.


Sorry for the false alarm.