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Bild/Foto
I was flipping through some of my astronomy photos and I came across this, which I must have shoved in there for lack of a better place to stash it. I howled with laughter.

#space #astronomy #funny #humour #Pluto #OhFrank
 
Bild/Foto
I was flipping through some of my astronomy photos and I came across this, which I must have shoved in there for lack of a better place to stash it. I howled with laughter.

#space #astronomy #funny #humour #Pluto #OhFrank
 
Just had my first rejection of a paper. I don't actually know why it was rejected, because the referee's lengthy comments contain basically no information besides, "I don't find this result convincing". That's extremely frustrating. We gave a clearly defined objective procedure explaining why our detections are real and not the result of noise. To then simply say, "I don't believe you" without giving any hint of a reason is extremely unprofessional and belittles the work that went into this. It also denies us any way to argue against it. Readers are of course always free to disagree for any reason, but a referee ought to justify their reasons - if they can't do this, then they should accept the importance of people publishing results they disagree with.

I have no idea why this result is in any way controversial. All it does is find a signature of galaxy evolution that's consistent with known processes, other observations, and theoretical models. Baffles the heck out of me. Not sure what we're gonna do next - expect more rants pending conversations with co-authors.

#Science
#Astronomy
 

Infrequent flyer


A question sent in to New Scientist reads,
"My wife told me I should get out more. I replied that I am just about to celebrate my 66th free trip around the sun. Can anyone tell me how far I have traveled around the galaxy during that time?"
All of the information required to answer this question to a ballpark level of accuracy — along with a little elementary arithmetic — can be found in the Galaxy Song from Monty Python's comedy film The Meaning Of Life.
"We're thirty thousand light-years from galactic central point,
We go 'round every two hundred million years..."
So the circumference of the Earth's orbit is (roughly) pi times two times thirty thousand light years. That's approximately 188,495 light years. And we take 200 million years to complete an orbit, which means each year we cover 188,495/200,000,000 light years, which is 0.00094 light years.

So how far is a light-year?
"As fast as it can go, the speed of light, you know,
Twelve million miles a minute, and that's the fastest speed there is"
Twelve million is actually a bit high. C is precisely 299792458 meters per second¹, which is 186,282.4 miles per second, and that works out to 11,176,943 miles per minute. 186,282.4 miles times 86400 seconds per day times 365.24 days per year gives 5,878,464,425,192.5 miles to the light year. Each year we travel 0.00094 of those around the galaxy, which is 5,525,756,559.7 miles, or just over five and a half trillion miles. Multiply by 66 and you get 364,699,932,939 miles, give or take a few hundred yards.

So there's your galactic travel — call it 364.7 trillion miles over 66 years. I'm pretty certain that many frequent flyer miles upgrades you to a first-class seat.

#science #astronomy #MontyPython
¹ Yes, PRECISELY 299792458 meters per second. Because that's how we now define the meter: 1/299,792,458 of the distance traveled by light in a vacuum in free space in one second.
 

Infrequent flyer


A question sent in to New Scientist reads,
"My wife told me I should get out more. I replied that I am just about to celebrate my 66th free trip around the sun. Can anyone tell me how far I have traveled around the galaxy during that time?"
All of the information required to answer this question to a ballpark level of accuracy — along with a little elementary arithmetic — can be found in the Galaxy Song from Monty Python's comedy film The Meaning Of Life.
"We're thirty thousand light-years from galactic central point,
We go 'round every two hundred million years..."
So the circumference of the Earth's orbit is (roughly) pi times two times thirty thousand light years. That's approximately 188,495 light years. And we take 200 million years to complete an orbit, which means each year we cover 188,495/200,000,000 light years, which is 0.00094 light years.

So how far is a light-year?
"As fast as it can go, the speed of light, you know,
Twelve million miles a minute, and that's the fastest speed there is"
Twelve million is actually a bit high. C is precisely 299792458 meters per second¹, which is 186,282.4 miles per second, and that works out to 11,176,943 miles per minute. 186,282.4 miles times 86400 seconds per day times 365.24 days per year gives 5,878,464,425,192.5 miles to the light year. Each year we travel 0.00094 of those around the galaxy, which is 5,525,756,559.7 miles, or just over five and a half trillion miles. Multiply by 66 and you get 364,699,932,939 miles, give or take a few hundred yards.

So there's your galactic travel — call it 364.7 trillion miles over 66 years. I'm pretty certain that many frequent flyer miles upgrades you to a first-class seat.

#science #astronomy #MontyPython
¹ Yes, PRECISELY 299792458 meters per second. Because that's how we now define the meter: 1/299,792,458 of the distance traveled by light in a vacuum in free space in one second.
 

Spectacular “Galaxy” Flowers Look Like They Hold the Universe in Their Petals


#flowers #nature #galaxy #space #astronomy #universe
Spectacular “Galaxy” Flowers Look Like They Hold the Universe in Their Petals
 

Spectacular “Galaxy” Flowers Look Like They Hold the Universe in Their Petals


#flowers #nature #galaxy #space #astronomy #universe
Spectacular “Galaxy” Flowers Look Like They Hold the Universe in Their Petals
 
from the New Horizons flyby of 2014 MU69 are out, based on 10% of the data sent back by the probe so far.
For many at the Johns Hopkins Applied Physics Laboratory, January 1 this year didn't mean a New Year's celebration. Instead, it meant the first arrival of data from New Horizons' visit to a small Kuiper Belt object. But, like its earlier flyby of Pluto, the probe was instructed to grab all the data it could and deal with getting it back to Earth later. The full set of everything New Horizons captured won't be available for more than a year yet. But with 10 percent of the total cache in hand, researchers decided they had enough to do the first analysis of 2014 MU69.
[...]
Overall, 2014 MU69 looks exactly like what we'd hope for: a world that underwent some major changes immediately after its formation but has since become static, preserving its state largely as it was billions of years ago. Hopefully, more details on that state are sitting in storage on New Horizons. Because we're not likely to send something back to 2014 MU69 any time soon.
#Astronomy #Space #NewHorizons #Exploration #2014MU69 #UltimaThule #KuiperBeltObjects
 
from the New Horizons flyby of 2014 MU69 are out, based on 10% of the data sent back by the probe so far.
For many at the Johns Hopkins Applied Physics Laboratory, January 1 this year didn't mean a New Year's celebration. Instead, it meant the first arrival of data from New Horizons' visit to a small Kuiper Belt object. But, like its earlier flyby of Pluto, the probe was instructed to grab all the data it could and deal with getting it back to Earth later. The full set of everything New Horizons captured won't be available for more than a year yet. But with 10 percent of the total cache in hand, researchers decided they had enough to do the first analysis of 2014 MU69.
[...]
Overall, 2014 MU69 looks exactly like what we'd hope for: a world that underwent some major changes immediately after its formation but has since become static, preserving its state largely as it was billions of years ago. Hopefully, more details on that state are sitting in storage on New Horizons. Because we're not likely to send something back to 2014 MU69 any time soon.
#Astronomy #Space #NewHorizons #Exploration #2014MU69 #UltimaThule #KuiperBeltObjects
 
Where do magnetars come from? #science #astronomy
Two Neutron Stars Collide, Forming a Magnetar

D-brief: Two Neutron Stars Collide, Forming a Magnetar - D-brief (Alison Klesman)

 
Where do magnetars come from? #science #astronomy
Two Neutron Stars Collide, Forming a Magnetar

D-brief: Two Neutron Stars Collide, Forming a Magnetar - D-brief (Alison Klesman)

 
Andrew Chael is one of the scientists who helped to produce the famous image of black hole M87. He has taken to twitter to defend Kate Bouman who for some reason has attracted the most attention from the media for her part in imaging the black hole.
A number of keyboard warriors have been bleating on about the fact that the media have been giving her rather too much credit for her role, although Bouman has, in all her comments so far, pointed out it was very much a team effort.

#m87 #astronomy #blackhole
 
Andrew Chael is one of the scientists who helped to produce the famous image of black hole M87. He has taken to twitter to defend Kate Bouman who for some reason has attracted the most attention from the media for her part in imaging the black hole.
A number of keyboard warriors have been bleating on about the fact that the media have been giving her rather too much credit for her role, although Bouman has, in all her comments so far, pointed out it was very much a team effort.

#m87 #astronomy #blackhole
 
Bild/Foto

Best #BlackHole photo


Meet Katie Bouman, the woman that rendered the image, as it appears on her screen.

#WomenInScence #Science #Astronomy

https://twitter.com/MIT_CSAIL/status/1116020858282180609
 

It's Official: Astronomers Just Unveiled The First-Ever Direct Image of a Black Hole


Very COOL! But I'm underwhelmed. Artists' views are ever-so-much better. :)

https://giant.gfycat.com/ZestyRawIvorybilledwoodpecker.webm

#physics #black holes #astrophysics #astronomy #cosmology #Einstein #Hawking
 

It's Official: Astronomers Just Unveiled The First-Ever Direct Image of a Black Hole


Very COOL! But I'm underwhelmed. Artists' views are ever-so-much better. :)

https://giant.gfycat.com/ZestyRawIvorybilledwoodpecker.webm

#physics #black holes #astrophysics #astronomy #cosmology #Einstein #Hawking
 
YORP effect apparently has made this asteroid spin so fast, it's breaking up.

"[S]unlight [i.e., the YORP effect] can spin up an asteroid, making it rotate faster. That's no big deal in the short term, but in the long run it spells disaster: At some point the rock is spinning so rapidly that the centrifugal force outward on its surface balances the gravitational force inward. If you're a rock sitting on the surface, over time as the asteroid spins faster you feel less and less gravity. You weigh less!
[...]
Is this what's happening to Gault? Observations from the ground indicate it has a rotation rate of about 2 hours, and it turns out that's almost exactly where you expect the rotational speed to start causing effects like this! Also, the dust is leaving the asteroid relatively slowly, at speeds of under a meter per second (less than walking speed). That's also about what you'd expect from dust launched into space by a landside (and the rotational speed of the asteroid on the surface near the equator is about 2 meters per second, which also gives the dust a kick).
[...]
It all adds up: Gault has been getting spun up by the ethereal breeze of light from the Sun, and is now very close to the point where it'll fly itself apart."

#Science #Space #Astronomy #Asteroids #Dynamics #YorpEffect
 
YORP effect apparently has made this asteroid spin so fast, it's breaking up.

"[S]unlight [i.e., the YORP effect] can spin up an asteroid, making it rotate faster. That's no big deal in the short term, but in the long run it spells disaster: At some point the rock is spinning so rapidly that the centrifugal force outward on its surface balances the gravitational force inward. If you're a rock sitting on the surface, over time as the asteroid spins faster you feel less and less gravity. You weigh less!
[...]
Is this what's happening to Gault? Observations from the ground indicate it has a rotation rate of about 2 hours, and it turns out that's almost exactly where you expect the rotational speed to start causing effects like this! Also, the dust is leaving the asteroid relatively slowly, at speeds of under a meter per second (less than walking speed). That's also about what you'd expect from dust launched into space by a landside (and the rotational speed of the asteroid on the surface near the equator is about 2 meters per second, which also gives the dust a kick).
[...]
It all adds up: Gault has been getting spun up by the ethereal breeze of light from the Sun, and is now very close to the point where it'll fly itself apart."

#Science #Space #Astronomy #Asteroids #Dynamics #YorpEffect
 
Das alles könnt ihr im März April und May am Himmel der #Nordhalbkugel beobachten

Highlights of the North Spring Sky

Image Credit & Copyright: Universe2go.com

https://apod.nasa.gov/apod/ap190313.html #APoD


#Wissenschaft #science #Astronomie #astronomy #Nachthimmel #nightsky
 
The highest resolution image of MU69 taken by New Horizons is now available. Phil Plait explains what it shows and what it can tell us about the population of bodies out there.
After the monumentally successful flyby of Pluto in 2015, the New Horizons spacecraft continued on into the outer solar system. After traveling at more than a dozen kilometers per second out an additional billion kilometers or so, it shot past the odd little rocky iceball 2014 MU69 on January 1, 2019, passing it by the razor-thin margin of just 3,500 kilometers … and that was after traveling for over 6.6 billion kilometers from Earth!

New Horizons took a lot of data during this encounter, comparable to what it did at Pluto, and it'll be another year or more before it's all back on Earth. So the New Horizons team did a clever thing: They prioritized what images to send back first. Among the highest priorities was getting the highest-resolution image sent back from the closest encounter as quickly as possible.

And now that image is here.
[...]
You might think that being out there, exposed to space out past Neptune for billions of years, MU69 would be covered in craters. For Pluto that's not the case because we think its surface gets repaved, so to speak, from subsurface processes that bubble up liquid from the interior. However, MU69 is far too small for that, and is certainly solid throughout. So a dearth of craters means there must be a dearth of impactors.

Interestingly, some scientists actually predicted this! They used the number of small craters seen on Pluto and its huge moon Charon, together with measurements and estimates of sizes of small objects past Neptune (called trans-Neptunian objects [TNOs], or more specifically in this case the Kuiper Belt), first to try to figure out the size distribution of objects out there capable of hitting MU69, and then to predict the size distribution of craters on MU69. Keep in mind that this was all done before the MU69 encounter!
#Space #Astronomy #Asteroids #NewHorizons #MU69 #UltimaThule #Exploration
 
The highest resolution image of MU69 taken by New Horizons is now available. Phil Plait explains what it shows and what it can tell us about the population of bodies out there.
After the monumentally successful flyby of Pluto in 2015, the New Horizons spacecraft continued on into the outer solar system. After traveling at more than a dozen kilometers per second out an additional billion kilometers or so, it shot past the odd little rocky iceball 2014 MU69 on January 1, 2019, passing it by the razor-thin margin of just 3,500 kilometers … and that was after traveling for over 6.6 billion kilometers from Earth!

New Horizons took a lot of data during this encounter, comparable to what it did at Pluto, and it'll be another year or more before it's all back on Earth. So the New Horizons team did a clever thing: They prioritized what images to send back first. Among the highest priorities was getting the highest-resolution image sent back from the closest encounter as quickly as possible.

And now that image is here.
[...]
You might think that being out there, exposed to space out past Neptune for billions of years, MU69 would be covered in craters. For Pluto that's not the case because we think its surface gets repaved, so to speak, from subsurface processes that bubble up liquid from the interior. However, MU69 is far too small for that, and is certainly solid throughout. So a dearth of craters means there must be a dearth of impactors.

Interestingly, some scientists actually predicted this! They used the number of small craters seen on Pluto and its huge moon Charon, together with measurements and estimates of sizes of small objects past Neptune (called trans-Neptunian objects [TNOs], or more specifically in this case the Kuiper Belt), first to try to figure out the size distribution of objects out there capable of hitting MU69, and then to predict the size distribution of craters on MU69. Keep in mind that this was all done before the MU69 encounter!
#Space #Astronomy #Asteroids #NewHorizons #MU69 #UltimaThule #Exploration
 
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