Solar storm knocks out 40 newly launched satellites from Elon Musk's SpaceX
https://www.abc.net.au/news/2022-02-10/ ... /100818798
A geomagnetic storm triggered by a large burst of radiation from the Sun has disabled at least 40 of the 49 satellites newly launched by SpaceX as part of its Starlink internet communications network.
The incident was believed to mark the largest collective loss of satellites stemming from a single geomagnetic event, and was unique in the way it unfolded, Harvard-Smithsonian astrophysicist Jonathan McDowell said.
SpaceX said the satellites were hit last Friday, February 4, a day after being launched into a preliminary "low-deployment" orbit about 210 kilometres above Earth.
Elon Musk's company said it routinely put satellites into low orbits in order to be able to crash them back to Earth and incinerate them on re-entry if malfunctions were detected during initial system checks.
But it was not clear if the company had anticipated the severity of the extreme space weather conditions it faced.
The Thursday launch by a SpaceX Falcon 9 rocket flown from the Kennedy Space Center in Florida roughly coincided with a "geomagnetic storm watch" posted for last Wednesday and Thursday by the US Space Weather Prediction Center.
The alert warned that solar flare activity from a "full halo coronal mass ejection" — a large blast of solar plasma and electromagnetic radiation from the Sun's surface — was detected on January 29, and was likely to reach Earth as early as February 1.
The alert also said resulting geomagnetic storm conditions on Earth were "likely to persist" into February 3 "at weakening levels."
According to SpaceX, the speed and severity of the solar storm drastically increased atmospheric density at the satellites' low-orbit altitude, creating intense friction or drag that knocked out at least 40 of them.
Starlink operators tried commanding the satellites into a "safe mode" orbital configuration, allowing them to fly edge-on to minimise drag.
But those efforts failed for most of the satellites, forcing them into lower levels of the atmosphere where they burned up on re-entry, SpaceX said.
"This is unprecedented as far as I know," Dr McDowell said.
He said he believed it marked the single greatest loss of satellites from a solar storm, and the first mass satellite failure caused by an increase in atmospheric density, as opposed to bombardment of charged particles and electromagnetic radiation itself.
Dr McDowell said the incident raised questions of whether the elevated orbital drag caused by the storm exceeded design limits or whether SpaceX believed incorrectly that the satellites could handle so much density.
He said that if "they weren't expecting to have to handle that much density … it sounds like they weren't paying attention to the space weather reports".
SpaceX did not immediately respond to a request for comment.
The Los Angeles area-based rocket company, founded by billionaire entrepreneur Elon Musk, has launched hundreds of small satellites into orbit since 2019 as part of his Starlink service for broadband internet.
In a January 15 tweet, Musk said the network consisted of 1,469 active satellites, with 272 moving to operational orbits.
.....................................................................................................................
And on the bright side:
Elon Musk's SpaceX helps to restore Tongan internet, as Pacific nation battles growing COVID-19 outbreak
https://www.abc.net.au/news/2022-02-10/ ... /100819172
Billionaire Elon Musk is helping restore Tonga's internet access after a volcanic eruption and tsunami cut off the South Pacific nation more than three weeks ago, according to officials, with repairs on an undersea cable proving more difficult than first thought.
The tsunami triggered by the Hunga Tonga-Hunga Ha'pai volcano severed the sole fibre-optic cable that connects Tonga to the rest of the world and most people remain without reliable connections.
But with Mr Musk's involvement, there was hope that better connectivity would be restored soon via a satellite option.
A top official in neighbouring Fiji tweeted that a team from Mr Musk's SpaceX company was in Fiji establishing a station that would help reconnect Tonga through SpaceX satellites.
SpaceX runs a network of nearly 2,000 low-orbit satellites called Starlink, which provides internet service to remote places around the world.
Fiji's Acting Prime Minister and Attorney-General Aiyaz Sayed-Khaiyum tweeted about the SpaceX work, saying the volcano's shock wave had "shattered Tonga's internet connection, adding days of gut-wrenching uncertainty to disaster assessments."
A spokeswoman for Mr Sayed-Khaiyum said on Wednesday she was waiting for more information about the Starlink project before providing further details.
SpaceX did not respond to requests for comment.
The Starlink internet communications network took a hit earlier this month after a geomagnetic storm, triggered by a large burst of radiation from the Sun, disabled 40 of the 49 newly launched satellites.
New Zealand MP Dr Shane Reti wrote to Mr Musk in the wake of the volcano and tsunami, and asked the entrepreneur to provide urgent internet communication to Tonga.
Earlier this month, Dr Reti tweeted to say he was "very pleased" that SpaceX was in Fiji to work on the gateway.
Tonga Cable had warned that restoration of the undersea cable, which suffered two breaks from the volcano, could take a weeks with poor access to the site extending delays.
Astronomy, cosmology and space thread
Re: Astronomy, cosmology and space thread
May you be in heaven half an hour before the devil know`s you`re dead!
Re: Astronomy, cosmology and space thread
Why the International Space Station will crash down into the Pacific Ocean's 'spacecraft graveyard'
https://www.abc.net.au/news/2022-02-12/ ... /100817404
The International Space Station (ISS) will join hundreds of articles of space junk littered across the ocean floor in the Pacific when it is deorbited from space in 2031, renewing concerns about the environmental impact of the region's "spacecraft graveyard".
NASA announced that the ISS will fall from space to its final resting place at Point Nemo in the South Pacific Ocean, to lay among about 300 spacecraft including Russia's Mir space station and China's Tiangong-1 space station.
Dr Brad Tucker is an astronomer at the Mount Stromlo Observatory in Canberra and said as the largest spacecraft to ever be deorbited, a controlled re-entry into the South Pacific was critical to bring the ISS back safely.
"It's about the size of a football field. It weighs about 450 tons," Dr Tucker said.
"So things like the Mir — Russia's space station — was a fraction of the size.
"That's actually why bringing it down somewhere near this spacecraft graveyard is even doubly important because lots of bits of it will fragment [and] there will be large bits that come back down to earth."
Point Nemo is located about halfway between New Zealand and Chile and was chosen because of its position as the furthest point from land in any direction, limiting the risk of space junk falling near inhabited areas.
"So this place has been purposely known for deorbiting craft in such a way that there's almost an artificial reef — a graveyard full of old spacecraft bits that are lying there in the ocean," Dr Tucker said.
"This still isn't the best solution, we don't actually really like this solution. It's the least bad option there is.
"You're still landing in the ocean, that's still not a great thing, but ... it poses the least amount of risk given all the other possibilities."
Associate Professor Alice Gorman is a space archaeologist at Flinders University and said many parts of spacecraft burn up as they make their way back down to earth.
But she said robust objects like fuel tanks can pose a problem, depending on whether they are intact, the level of fuel and the type of fuel inside.
"There are a number of spacecraft fuels which end up decaying into fairly benign products, they don't have any implications, but there are also some quite toxic spacecraft fuels. Hydrazine is one of these," Professor Gorman said.
Dr Tucker added Hydrazine was one of the most common fuels used in spacecraft by countries around the world.
"If a fuel tank splits open while it's still in the re-entry process, those fuels will evaporate, but if it were to break up upon falling to the ocean floor and release some of those fuels that could have a not so great environmental impact," Professor Gorman said.
She said predictive modelling will have been done to gauge how well components like fuel tanks will survive coming back through the atmosphere, the fuel load and the dangers once it reaches the ocean floor.
"So there are some environmental questions to be answered," Professor Gorman said.
In a statement, Greenpeace said it was clear "we need to stop treating the ocean like a dumping ground".
"We need to protect the ocean to allow it to thrive into the future — that means not dumping our pollution into it.
"Our wellbeing is inherently linked to the health of the ocean, so it's in all our best interests to look after it."
NASA did not respond to the ABC's request for comment in relation to the environmental concerns associated with the ISS's landing at Point Nemo.
'No other options'
Professor Gorman said there wasn't a safer option to bring back this kind of spacecraft.
"There will be some environmental impacts, although we may not know exactly what they are, but it's not like there is the choice," she said.
"It's not like you can say, 'oh, the impacts are too great, we will leave it in orbit', because that's not possible.
"Eventually, if we left it there without fuel to continually help it maintain its position, it would drift back down, and we wouldn't have any control of where it landed."
This happened in Australia in 1979 when the first United States space station, Skylab, had an uncontrolled re-entry over Western Australia.
Media reports from the time said the space station disintegrated "in a blaze of fireworks" over the Indian Ocean before debris fell across the desert.
Fortunately, no one was injured.
Professor Gorman also said if environmental impacts were minimised, deorbited spacecraft could act like shipwrecks and create new habitats for marine life.
She said space companies were working to improve their impact through initiatives like the Space Sustainability Rating, which is used to assess how green a company is.
https://www.abc.net.au/news/2022-02-12/ ... /100817404
The International Space Station (ISS) will join hundreds of articles of space junk littered across the ocean floor in the Pacific when it is deorbited from space in 2031, renewing concerns about the environmental impact of the region's "spacecraft graveyard".
NASA announced that the ISS will fall from space to its final resting place at Point Nemo in the South Pacific Ocean, to lay among about 300 spacecraft including Russia's Mir space station and China's Tiangong-1 space station.
Dr Brad Tucker is an astronomer at the Mount Stromlo Observatory in Canberra and said as the largest spacecraft to ever be deorbited, a controlled re-entry into the South Pacific was critical to bring the ISS back safely.
"It's about the size of a football field. It weighs about 450 tons," Dr Tucker said.
"So things like the Mir — Russia's space station — was a fraction of the size.
"That's actually why bringing it down somewhere near this spacecraft graveyard is even doubly important because lots of bits of it will fragment [and] there will be large bits that come back down to earth."
Point Nemo is located about halfway between New Zealand and Chile and was chosen because of its position as the furthest point from land in any direction, limiting the risk of space junk falling near inhabited areas.
"So this place has been purposely known for deorbiting craft in such a way that there's almost an artificial reef — a graveyard full of old spacecraft bits that are lying there in the ocean," Dr Tucker said.
"This still isn't the best solution, we don't actually really like this solution. It's the least bad option there is.
"You're still landing in the ocean, that's still not a great thing, but ... it poses the least amount of risk given all the other possibilities."
Associate Professor Alice Gorman is a space archaeologist at Flinders University and said many parts of spacecraft burn up as they make their way back down to earth.
But she said robust objects like fuel tanks can pose a problem, depending on whether they are intact, the level of fuel and the type of fuel inside.
"There are a number of spacecraft fuels which end up decaying into fairly benign products, they don't have any implications, but there are also some quite toxic spacecraft fuels. Hydrazine is one of these," Professor Gorman said.
Dr Tucker added Hydrazine was one of the most common fuels used in spacecraft by countries around the world.
"If a fuel tank splits open while it's still in the re-entry process, those fuels will evaporate, but if it were to break up upon falling to the ocean floor and release some of those fuels that could have a not so great environmental impact," Professor Gorman said.
She said predictive modelling will have been done to gauge how well components like fuel tanks will survive coming back through the atmosphere, the fuel load and the dangers once it reaches the ocean floor.
"So there are some environmental questions to be answered," Professor Gorman said.
In a statement, Greenpeace said it was clear "we need to stop treating the ocean like a dumping ground".
"We need to protect the ocean to allow it to thrive into the future — that means not dumping our pollution into it.
"Our wellbeing is inherently linked to the health of the ocean, so it's in all our best interests to look after it."
NASA did not respond to the ABC's request for comment in relation to the environmental concerns associated with the ISS's landing at Point Nemo.
'No other options'
Professor Gorman said there wasn't a safer option to bring back this kind of spacecraft.
"There will be some environmental impacts, although we may not know exactly what they are, but it's not like there is the choice," she said.
"It's not like you can say, 'oh, the impacts are too great, we will leave it in orbit', because that's not possible.
"Eventually, if we left it there without fuel to continually help it maintain its position, it would drift back down, and we wouldn't have any control of where it landed."
This happened in Australia in 1979 when the first United States space station, Skylab, had an uncontrolled re-entry over Western Australia.
Media reports from the time said the space station disintegrated "in a blaze of fireworks" over the Indian Ocean before debris fell across the desert.
Fortunately, no one was injured.
Professor Gorman also said if environmental impacts were minimised, deorbited spacecraft could act like shipwrecks and create new habitats for marine life.
She said space companies were working to improve their impact through initiatives like the Space Sustainability Rating, which is used to assess how green a company is.
- The oxygen tank of the Skylab space station that fell over WA in 1979.(Supplied: Geoff Grewar)
- skylab.jpg (229.59 KiB) Viewed 879 times
May you be in heaven half an hour before the devil know`s you`re dead!
Re: Astronomy, cosmology and space thread
It is said that time is money (except in Thailand, where money comes first). How to keep track of accurate time has dogged people for centuries.
.....................................................................................................
How world's most precise clock could transform fundamental physics
https://www.bangkokpost.com/world/22656 ... al-physics
WASHINGTON: Einstein's theory of general relativity holds that a massive body like Earth curves space-time, causing time to slow as you approach the object -- so a person on top of a mountain ages a tiny bit faster than someone at sea level.
US scientists have now confirmed the theory at the smallest scale ever, demonstrating that clocks tick at different rates when separated by fractions of a millimeter.
Jun Ye, of the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder, told AFP their new clock was "by far" the most precise ever built -- and could pave the way for new discoveries in quantum mechanics, the rulebook for the subatomic world.
Ye and colleagues published their findings Wednesday in the prestigious journal Nature, describing the engineering advances that enabled them to build a device 50 times more precise than today's best atomic clocks.
It wasn't until the invention of atomic clocks -- which keep time by detecting the transition between two energy states inside an atom exposed to a particular frequency -- that scientists could prove Albert Einstein's 1915 theory.
Early experiments included the Gravity Probe A of 1976, which involved a spacecraft 10,000 kilometres above Earth's surface and showed that an onboard clock was faster than an equivalent on Earth by one second every 73 years.
Since then, clocks have become more and more precise, and thus better able to detect the effects of relativity.
In 2010, NIST scientists observed time moving at different rates when their clock was moved 33 centimeters (just over a foot) higher.
- Theory of everything -
Ye's key breakthrough was working with webs of light, known as optical lattices, to trap atoms in orderly arrangements. This is to stop the atoms from falling due to gravity or otherwise moving, resulting in a loss of accuracy.
Inside Ye's new clock are 100,000 strontium atoms, layered on top of each other like a stack of pancakes, in total about a millimeter high.
The clock is so precise that when the scientists divided the stack into two, they could detect differences in time in the top and bottom halves.
At this level of accuracy, clocks essentially act as sensors.
"Space and time are connected," said Ye. "And with time measurement so precise, you can actually see how space is changing in real time -- Earth is a lively, living body."
Such clocks spread out over a volcanically-active region could tell geologists the difference between solid rock and lava, helping predict eruptions.
Or, for example, study how global warming is causing glaciers to melt and oceans to rise.
What excites Ye most, however, is how future clocks could usher in a completely new realm of physics.
The current clock can detect time differences across 200 microns -- but if that was brought down to 20 microns, it could start to probe the quantum world, helping bridge disparities in theory.
While relativity beautifully explains how large objects like planets and galaxies behave, it is famously incompatible with quantum mechanics, which deals with the very small.
According to quantum theory, every particle is also a wave -- and can occupy multiple places at the same time, something known as superposition. But it is not clear how an object in two places at once would distort space-time, per Einstein's theory.
The intersection of the two fields therefore would bring physics a step closer to a unifying "theory of everything" that explains all physical phenomena of the cosmos.
.....................................................................................................
How world's most precise clock could transform fundamental physics
https://www.bangkokpost.com/world/22656 ... al-physics
WASHINGTON: Einstein's theory of general relativity holds that a massive body like Earth curves space-time, causing time to slow as you approach the object -- so a person on top of a mountain ages a tiny bit faster than someone at sea level.
US scientists have now confirmed the theory at the smallest scale ever, demonstrating that clocks tick at different rates when separated by fractions of a millimeter.
Jun Ye, of the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder, told AFP their new clock was "by far" the most precise ever built -- and could pave the way for new discoveries in quantum mechanics, the rulebook for the subatomic world.
Ye and colleagues published their findings Wednesday in the prestigious journal Nature, describing the engineering advances that enabled them to build a device 50 times more precise than today's best atomic clocks.
It wasn't until the invention of atomic clocks -- which keep time by detecting the transition between two energy states inside an atom exposed to a particular frequency -- that scientists could prove Albert Einstein's 1915 theory.
Early experiments included the Gravity Probe A of 1976, which involved a spacecraft 10,000 kilometres above Earth's surface and showed that an onboard clock was faster than an equivalent on Earth by one second every 73 years.
Since then, clocks have become more and more precise, and thus better able to detect the effects of relativity.
In 2010, NIST scientists observed time moving at different rates when their clock was moved 33 centimeters (just over a foot) higher.
- Theory of everything -
Ye's key breakthrough was working with webs of light, known as optical lattices, to trap atoms in orderly arrangements. This is to stop the atoms from falling due to gravity or otherwise moving, resulting in a loss of accuracy.
Inside Ye's new clock are 100,000 strontium atoms, layered on top of each other like a stack of pancakes, in total about a millimeter high.
The clock is so precise that when the scientists divided the stack into two, they could detect differences in time in the top and bottom halves.
At this level of accuracy, clocks essentially act as sensors.
"Space and time are connected," said Ye. "And with time measurement so precise, you can actually see how space is changing in real time -- Earth is a lively, living body."
Such clocks spread out over a volcanically-active region could tell geologists the difference between solid rock and lava, helping predict eruptions.
Or, for example, study how global warming is causing glaciers to melt and oceans to rise.
What excites Ye most, however, is how future clocks could usher in a completely new realm of physics.
The current clock can detect time differences across 200 microns -- but if that was brought down to 20 microns, it could start to probe the quantum world, helping bridge disparities in theory.
While relativity beautifully explains how large objects like planets and galaxies behave, it is famously incompatible with quantum mechanics, which deals with the very small.
According to quantum theory, every particle is also a wave -- and can occupy multiple places at the same time, something known as superposition. But it is not clear how an object in two places at once would distort space-time, per Einstein's theory.
The intersection of the two fields therefore would bring physics a step closer to a unifying "theory of everything" that explains all physical phenomena of the cosmos.
May you be in heaven half an hour before the devil know`s you`re dead!
-
Dannie Boy
- Hero
- Posts: 13758
- Joined: Wed Jan 13, 2010 8:12 pm
- Location: Closer to Cha Am than Hua Hin
Astronomy, cosmology and space thread
Fascinating stuff, but I’m not going to lose any sleep over it!!
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
Re: Astronomy, cosmology and space thread
Don't put your alarm clock too high!Dannie Boy wrote: ↑Thu Feb 17, 2022 10:47 am Fascinating stuff, but I’m not going to lose any sleep over it!!
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Re: Astronomy, cosmology and space thread
NASA's James Webb Space Telescope captures test image of star and ancient galaxies over 2,000 light-years away
https://www.abc.net.au/news/2022-03-17/ ... /100916480
NASA's new space telescope has gazed into the distant universe and captured a perfect vision: a spiky image of a faraway star photobombed by thousands of ancient galaxies.
The image released on Wednesday from the James Webb Space Telescope is a test shot — not an official scientific observation — to see how its 18 hexagonal mirrors worked together for a single, coordinated image taken 1.6 million kilometres away from Earth.
Officials said it had worked "better than expected".
Last month, NASA looked at a much-closer star with 18 separate images from its mirror segments.
Scientists said they were "giddy" as they watched the latest test photos arrive.
NASA's test image was aimed at a star 100 times fainter than the human eye can see, one that was 2,000 light-years away.
A light-year is nearly 9.7 trillion kilometres.
The shape of Webb's mirrors and its filters made the shimmering star look more red and spiky, but the background really stole the show.
"You can't help but see those thousands of galaxies behind it, really gorgeous," Webb operations project scientist Jane Rigby said.
Those galaxies are several billions of years old.
Eventually, scientists hope Webb will see so far away and back in time that it will only be "a couple hundred million years after the Big Bang", she said.
The first scientific images will not come until late June or early July.
Webb — the $US10 billion ($13.7 billion) telescope that is the successor to the nearly 32-year-old Hubble Space Telescope — blasted off from South America in December and reached its designated orbit in January.
https://www.abc.net.au/news/2022-03-17/ ... /100916480
NASA's new space telescope has gazed into the distant universe and captured a perfect vision: a spiky image of a faraway star photobombed by thousands of ancient galaxies.
The image released on Wednesday from the James Webb Space Telescope is a test shot — not an official scientific observation — to see how its 18 hexagonal mirrors worked together for a single, coordinated image taken 1.6 million kilometres away from Earth.
Officials said it had worked "better than expected".
Last month, NASA looked at a much-closer star with 18 separate images from its mirror segments.
Scientists said they were "giddy" as they watched the latest test photos arrive.
NASA's test image was aimed at a star 100 times fainter than the human eye can see, one that was 2,000 light-years away.
A light-year is nearly 9.7 trillion kilometres.
The shape of Webb's mirrors and its filters made the shimmering star look more red and spiky, but the background really stole the show.
"You can't help but see those thousands of galaxies behind it, really gorgeous," Webb operations project scientist Jane Rigby said.
Those galaxies are several billions of years old.
Eventually, scientists hope Webb will see so far away and back in time that it will only be "a couple hundred million years after the Big Bang", she said.
The first scientific images will not come until late June or early July.
Webb — the $US10 billion ($13.7 billion) telescope that is the successor to the nearly 32-year-old Hubble Space Telescope — blasted off from South America in December and reached its designated orbit in January.
May you be in heaven half an hour before the devil know`s you`re dead!
-
pharvey
- Moderator
- Posts: 15700
- Joined: Sat Aug 29, 2009 10:21 am
- Location: Sir Fynwy - God's Country
Re: Astronomy, cosmology and space thread
Have been following this myself - absolutely incredible quite frankly.
Looking forward to seeing what the future (and past) will bing!!
"Hope is a good thing, maybe the best of things" - Yma o Hyd.
Re: Astronomy, cosmology and space thread
Bloody long way to go for a call out to adjust the damn thing!
NASA's test image was aimed at a star 100 times fainter than the human eye can see, one that was 2,000 light-years away.
A light-year is nearly 9.7 trillion kilometres.
May you be in heaven half an hour before the devil know`s you`re dead!
Re: Astronomy, cosmology and space thread
NASA's new Artemis-1 Moon mission begins 11-hour rollout to launch pad
https://www.abc.net.au/news/2022-03-18/ ... /100921464
NASA's massive new rocket has begun its first journey to a launch pad ahead of a battery of tests that will clear it to blast off to the Moon this winter.
It left the Kennedy Space Center's Vehicle Assembly Building and began an 11-hour journey on a crawler-transporter to the hallowed Launch Complex 39B, 6.5 kilometres away.
Here's what we know.
How big is big?
With the Orion crew capsule fixed on top, the Space Launch System (SLS) Block 1 stands 98 metres high — taller than the Statue of Liberty, but a little smaller than the Saturn V rockets that powered the Apollo missions to the Moon.
Despite this, it will produce 8.8 million pounds of maximum thrust (39.1 Meganewtons), 15 per cent more than the Saturn V, meaning it's expected to be the world's most powerful rocket at the time it begins operating.
"Ladies and gentlemen, the world's most powerful rocket ever, right here," NASA administrator Bill Nelson told a crowd.
"We imagine, we build, we never stop pushing the envelope of what is possible."
A symbol of US space ambition, it also comes with a hefty price tag: $US4.1 billion ($5.56 billion) per launch for the first four Artemis missions, NASA Inspector General Paul Martin told Congress this month.
After reaching the launch pad, there are roughly two more weeks' worth of checks before what's known as the "wet dress rehearsal".
The SLS team will load more than 3.2 million litres of cryogenic propellant into the rocket and practice every phase of launch countdown, stopping 10 seconds before blast off.
Where will it go?
NASA is targeting May as the earliest window for Artemis-1, an uncrewed lunar mission that will be the first integrated flight for SLS and Orion.
SLS will first place Orion into a low Earth orbit, and then, using its upper stage, perform what's called a trans-lunar injection.
This manoeuvre is necessary to send Orion 280,000 miles beyond Earth and 40,000 miles beyond the Moon — further than any spaceship capable of carrying humans has ventured.
On its three-week mission, Orion will deploy 10 shoebox-size satellites known as CubeSats to gather information on the deep space environment.
Its "passengers" will include three mannequins collecting radiation data, and a plush Snoopy toy, long a NASA mascot.
It will journey around the far side of the Moon, using thrust provided by the European Space Agency (ESA) thruster, and finally make its way back to Earth, where its heat shield will be tested against the atmosphere.
Splashdown will take place in the Pacific, off the coast of California.
Artemis-2 will be the first crewed test, flying around the Moon but not landing, while Artemis-3, planned for 2025, will see the first woman and first person of colour touch down on the lunar south pole.
NASA wants to build a permanent presence on the Moon, and use it as a proving ground for technologies necessary for a Mars mission, sometime in the 2030s, using a Block 2 evolution of the SLS.
What's the competition?
NASA calls SLS a "super-heavy lift exploration class vehicle." The only currently operational super-heavy rocket is SpaceX's Falcon Heavy, which is smaller.
Elon Musk's company is also developing its own deep space rocket, the fully reusable Starship, which he has said should be ready for an orbital test this year.
Starship would be both bigger and more powerful than SLS: 120 metres with 17 million pounds of thrust. It could also be considerably cheaper.
The tycoon has suggested that within years, the cost per launch could be as little as $US10 million.
Direct comparisons are complicated by the fact that while SLS is designed to fly direct to its destinations, SpaceX foresees putting a Starship into orbit, and then refuelling it with another Starship so it can continue its journey, to extend range and payload.
NASA has also contracted a version of Starship as a lunar descent vehicle for Artemis.
Other super-heavy rockets under development include Blue Origin's New Glenn, China's Long March 9 and Russia's Yenisei.
https://www.abc.net.au/news/2022-03-18/ ... /100921464
NASA's massive new rocket has begun its first journey to a launch pad ahead of a battery of tests that will clear it to blast off to the Moon this winter.
It left the Kennedy Space Center's Vehicle Assembly Building and began an 11-hour journey on a crawler-transporter to the hallowed Launch Complex 39B, 6.5 kilometres away.
Here's what we know.
How big is big?
With the Orion crew capsule fixed on top, the Space Launch System (SLS) Block 1 stands 98 metres high — taller than the Statue of Liberty, but a little smaller than the Saturn V rockets that powered the Apollo missions to the Moon.
Despite this, it will produce 8.8 million pounds of maximum thrust (39.1 Meganewtons), 15 per cent more than the Saturn V, meaning it's expected to be the world's most powerful rocket at the time it begins operating.
"Ladies and gentlemen, the world's most powerful rocket ever, right here," NASA administrator Bill Nelson told a crowd.
"We imagine, we build, we never stop pushing the envelope of what is possible."
A symbol of US space ambition, it also comes with a hefty price tag: $US4.1 billion ($5.56 billion) per launch for the first four Artemis missions, NASA Inspector General Paul Martin told Congress this month.
After reaching the launch pad, there are roughly two more weeks' worth of checks before what's known as the "wet dress rehearsal".
The SLS team will load more than 3.2 million litres of cryogenic propellant into the rocket and practice every phase of launch countdown, stopping 10 seconds before blast off.
Where will it go?
NASA is targeting May as the earliest window for Artemis-1, an uncrewed lunar mission that will be the first integrated flight for SLS and Orion.
SLS will first place Orion into a low Earth orbit, and then, using its upper stage, perform what's called a trans-lunar injection.
This manoeuvre is necessary to send Orion 280,000 miles beyond Earth and 40,000 miles beyond the Moon — further than any spaceship capable of carrying humans has ventured.
On its three-week mission, Orion will deploy 10 shoebox-size satellites known as CubeSats to gather information on the deep space environment.
Its "passengers" will include three mannequins collecting radiation data, and a plush Snoopy toy, long a NASA mascot.
It will journey around the far side of the Moon, using thrust provided by the European Space Agency (ESA) thruster, and finally make its way back to Earth, where its heat shield will be tested against the atmosphere.
Splashdown will take place in the Pacific, off the coast of California.
Artemis-2 will be the first crewed test, flying around the Moon but not landing, while Artemis-3, planned for 2025, will see the first woman and first person of colour touch down on the lunar south pole.
NASA wants to build a permanent presence on the Moon, and use it as a proving ground for technologies necessary for a Mars mission, sometime in the 2030s, using a Block 2 evolution of the SLS.
What's the competition?
NASA calls SLS a "super-heavy lift exploration class vehicle." The only currently operational super-heavy rocket is SpaceX's Falcon Heavy, which is smaller.
Elon Musk's company is also developing its own deep space rocket, the fully reusable Starship, which he has said should be ready for an orbital test this year.
Starship would be both bigger and more powerful than SLS: 120 metres with 17 million pounds of thrust. It could also be considerably cheaper.
The tycoon has suggested that within years, the cost per launch could be as little as $US10 million.
Direct comparisons are complicated by the fact that while SLS is designed to fly direct to its destinations, SpaceX foresees putting a Starship into orbit, and then refuelling it with another Starship so it can continue its journey, to extend range and payload.
NASA has also contracted a version of Starship as a lunar descent vehicle for Artemis.
Other super-heavy rockets under development include Blue Origin's New Glenn, China's Long March 9 and Russia's Yenisei.
- NASA's Artemis rocket, with the Orion spacecraft onboard, started its journey to the launch pad.(AP: Aubrey Gemignani)
- Artemis.jpg (103.59 KiB) Viewed 733 times
May you be in heaven half an hour before the devil know`s you`re dead!
-
pharvey
- Moderator
- Posts: 15700
- Joined: Sat Aug 29, 2009 10:21 am
- Location: Sir Fynwy - God's Country
Re: Astronomy, cosmology and space thread
Full article and also some interesting comparisons between Hubble and the James Webb Telescope at link: -
https://www.bbc.co.uk/news/science-environment-60931100
Hubble: 'Single Star' Detected at Record-Breaking Distance
"They've nicknamed it "Earendel" and it's the most distant, single star yet imaged by a telescope.
The light from this object has taken 12.9 billion years to reach us.
It's at the sort of distance that telescopes normally would only be able to resolve galaxies containing millions of stars.
But the Hubble space observatory has picked out Earendel individually by exploiting a natural phenomenon that's akin to using a zoom lens.
It's called gravitational lensing and it works like this: If there is a great cluster of galaxies in the line of sight, the gravitational pull from this mass of matter will bend and magnify the light of more distant objects behind.
Usually, this is just other galaxies, but in this specific case Earendel was in a sweetspot in the lens effect.
"We got lucky. This is really extreme; it's really exciting to find something with such a high magnification," said Brian Welch, a PhD student from Johns Hopkins University in Maryland, US. "If you happen to hit that right sweetspot, like we have in this case, the magnification can grow up to factors of 1000s," he told BBC News.
The previous record-setter was a star called Icarus. Again, captured by Hubble, the light from this star took nine billion years to reach us.
Earendel is therefore significantly further away. We are seeing it a mere 900 million years after the Big Bang, or at a time when the Universe was only 6% of its current age."
https://www.bbc.co.uk/news/science-environment-60931100
Hubble: 'Single Star' Detected at Record-Breaking Distance
"They've nicknamed it "Earendel" and it's the most distant, single star yet imaged by a telescope.
The light from this object has taken 12.9 billion years to reach us.
It's at the sort of distance that telescopes normally would only be able to resolve galaxies containing millions of stars.
But the Hubble space observatory has picked out Earendel individually by exploiting a natural phenomenon that's akin to using a zoom lens.
It's called gravitational lensing and it works like this: If there is a great cluster of galaxies in the line of sight, the gravitational pull from this mass of matter will bend and magnify the light of more distant objects behind.
Usually, this is just other galaxies, but in this specific case Earendel was in a sweetspot in the lens effect.
"We got lucky. This is really extreme; it's really exciting to find something with such a high magnification," said Brian Welch, a PhD student from Johns Hopkins University in Maryland, US. "If you happen to hit that right sweetspot, like we have in this case, the magnification can grow up to factors of 1000s," he told BBC News.
The previous record-setter was a star called Icarus. Again, captured by Hubble, the light from this star took nine billion years to reach us.
Earendel is therefore significantly further away. We are seeing it a mere 900 million years after the Big Bang, or at a time when the Universe was only 6% of its current age."
"Hope is a good thing, maybe the best of things" - Yma o Hyd.
Re: Astronomy, cosmology and space thread
I believe that the most incredible part is that it is Hubble that has spotted it!
But it's worth celebrating for a moment the continued brilliance of Hubble. It was launched in 1990 and even as a new wonder observatory prepares to take up the reins, Hubble keeps turning out ground-breaking studies.
May you be in heaven half an hour before the devil know`s you`re dead!
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pharvey
- Moderator
- Posts: 15700
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Re: Astronomy, cosmology and space thread
Couldn't agree more!Nereus wrote: ↑Wed Apr 06, 2022 10:18 pm I believe that the most incredible part is that it is Hubble that has spotted it!
But it's worth celebrating for a moment the continued brilliance of Hubble. It was launched in 1990 and even as a new wonder observatory prepares to take up the reins, Hubble keeps turning out ground-breaking studies.
[EDIT] Worth noting the "dated technology" - We're talking 1977 when Congress gave approval for Hubble.
[EDIT 2] - Sorry. I also believe the James Webb Telescope was something like 2002 - some 20 years ago!
Incredible stuff that's happening, even more so how the technology can and will realistically move on.
"Hope is a good thing, maybe the best of things" - Yma o Hyd.
Re: Astronomy, cosmology and space thread
Hubble on the job again:
NASA's Hubble telescope detects largest comet nucleus ever found
https://www.abc.net.au/news/2022-04-14/ ... /100991908
Astronomers say they have seen the largest comet nucleus ever thanks to NASA's Hubble Space Telescope.
This luminous blue glow — named Comet C/2014 UN271 — was discovered by astronomers Pedro Bernardinelli and Gary Bernstein using archival images from the Cerro Tololo Inter-American Observatory in Chile.
The comet has been observed since 2010, when it was 4.8 billion kilometres away from the sun, and has been studied since.
According to NASA, its estimated diameter is approximately 85 miles or 137km across, making it larger than the ACT.
The comet's nucleus is about 50 times larger than that of most comets.
Its mass is estimated to be a staggering 450 trillion tonnes — a hundred thousand times greater than the mass of a typical comet found much closer to the Sun.
Comet is 'the tip of the iceberg'
A professor of planetary science and astronomy at the University of California, Los Angeles, David Jewitt, said in a statement: "This comet is literally the tip of the iceberg for many thousands of comets that are too faint to see in the more distant parts of the solar system.
"We've always suspected this comet had to be big because it is so bright at such a large distance. Now we confirm it is," he added.
Professor Jewitt co-authored a recent study of the comet in The Astrophysical Journal Letters, along with lead author Man-To Hui from Macau University of Science and Technology.
How was it spotted?
According to NASA, the comet is currently too far away for its nucleus to be distinguished by Hubble.
The challenge in measuring the size of the comet was distinguishing its nucleus from the huge, dusty coma enveloping it — a cloud of gases that surrounds the nucleus of a comet.
But what the Hubble data did reveal was a bright spike of light at the nucleus's location.
Dr Hui and his team made a computer model of the surrounding coma and adjusted it to fit the Hubble images.
Then, they removed the glow of the coma, revealing its starlike nucleus.
So, is it heading towards us or not?
Don't worry, we're not about to be in a real-life version of the film Don't Look Up.
The comet is travelling at 35,400 kilometres per hour from the edge of the solar system.
But NASA has assured us it will never get closer than 1.6 billion kilometres away from the Sun, which won't be until 2031.
NASA's Hubble telescope detects largest comet nucleus ever found
https://www.abc.net.au/news/2022-04-14/ ... /100991908
Astronomers say they have seen the largest comet nucleus ever thanks to NASA's Hubble Space Telescope.
This luminous blue glow — named Comet C/2014 UN271 — was discovered by astronomers Pedro Bernardinelli and Gary Bernstein using archival images from the Cerro Tololo Inter-American Observatory in Chile.
The comet has been observed since 2010, when it was 4.8 billion kilometres away from the sun, and has been studied since.
According to NASA, its estimated diameter is approximately 85 miles or 137km across, making it larger than the ACT.
The comet's nucleus is about 50 times larger than that of most comets.
Its mass is estimated to be a staggering 450 trillion tonnes — a hundred thousand times greater than the mass of a typical comet found much closer to the Sun.
Comet is 'the tip of the iceberg'
A professor of planetary science and astronomy at the University of California, Los Angeles, David Jewitt, said in a statement: "This comet is literally the tip of the iceberg for many thousands of comets that are too faint to see in the more distant parts of the solar system.
"We've always suspected this comet had to be big because it is so bright at such a large distance. Now we confirm it is," he added.
Professor Jewitt co-authored a recent study of the comet in The Astrophysical Journal Letters, along with lead author Man-To Hui from Macau University of Science and Technology.
How was it spotted?
According to NASA, the comet is currently too far away for its nucleus to be distinguished by Hubble.
The challenge in measuring the size of the comet was distinguishing its nucleus from the huge, dusty coma enveloping it — a cloud of gases that surrounds the nucleus of a comet.
But what the Hubble data did reveal was a bright spike of light at the nucleus's location.
Dr Hui and his team made a computer model of the surrounding coma and adjusted it to fit the Hubble images.
Then, they removed the glow of the coma, revealing its starlike nucleus.
So, is it heading towards us or not?
Don't worry, we're not about to be in a real-life version of the film Don't Look Up.
The comet is travelling at 35,400 kilometres per hour from the edge of the solar system.
But NASA has assured us it will never get closer than 1.6 billion kilometres away from the Sun, which won't be until 2031.
- The initial observation revealed a shell of dust and gas surrounding the comet's nucleus.(Supplied: NASA/Space Telescope Science Institute/Macau University of Science and Technology)
- 6c407a38d5665f2d82d3e04e33403301.jpg (50 KiB) Viewed 562 times
May you be in heaven half an hour before the devil know`s you`re dead!
Re: Astronomy, cosmology and space thread
Uranus is a very weird planet. Here's why astronomers want to send a probe to it
https://www.abc.net.au/news/science/202 ... /101023950
Of all our planets, Uranus has had a tough time in the reputation stakes over the years.
Its name alone is the butt of jokes, and NASA's announcement last week that it wanted to target Uranus with a probe was a comedian's field day.
But planetary scientists are over the moon our seventh planet is finally going to get its day in the sun.
The fact that it's so far away from the Sun – 2.9 billion kilometres – is one of the reasons it has been so lonely and misunderstood.
Unlike its flashy siblings Jupiter and Saturn, Uranus has only had one visitor — a brief flyby by the Voyager 2 spacecraft in 1986, said Amy Simon, one of the NASA scientists who has been advocating for a mission to the planet.
"It's one of the strangest planets in the Solar System and yet we haven't been back there," Dr Simon said.
"This really is huge, unexplored territory."
Helen Maynard-Casely, an Australian planetary scientist at ANSTO who studies ice giant planets, agrees.
"It's just a shame that Uranus and Neptune have been ignored so much," Dr Maynard-Casely says.
"As soon as we start studying one of the two, it will reveal so much about the other one."
So let's see what makes this planet so cool (apart from the fact that at a very chilly minus-224 degrees Celsius, it holds the record for the coldest place in the Solar System).
It took 70 years to name (it could have been called George)
All the inner planets have been known since ancient times because they are easy to spot in the night sky, but Uranus was the first planet to be "discovered", and even then astronomers thought it was a comet or a star.
If William Herschel had his way in 1781, our seventh planet would have been called Georgian Sidus, or George's Star, after his patron King George III.
Seventy years later astronomers settled on Uranus.
While many people pronounce the planet as Ur-Anus, astronomers prefer to say Uran-us.
"I think there are many ways of pronouncing it but if you go for Ur-Anus, people snigger," says Jonti Horner, a planetary scientist at the University of Southern Queensland.
"It would have been a lot easier if Herschel had his way and it was called George."
But Uranus is much more regal. It was named after the Greek god of the sky, Ouranos, father of Saturn and grandfather of Jupiter.
Summer lasts for 42 years at the poles
Unlike all the other planets, Uranus is tipped on its side at an angle of 97.77 degrees.
"What that means is that it rolls along its orbit rather than spinning," Professor Horner says.
"It's a really very weird, very different place."
Its extreme tilt means that each pole continuously faces towards the Sun for 42 Earth years.
"Averaged through the course of the year, the poles get more sunlight and more energy than the equator, which is very different to other planets," Professor Horner says.
We don't know why the planet — and its bevvy of moons and rings that circle the equator — are on an angle.
One hypothesis, says Dr Simon, is that it was smashed into by something roughly the same size in the early Solar System.
But that doesn't explain how Uranus got its moons.
"It has all these small moons that are clearly in that same orbit and they had to have formed around the same time [as the planet]," Dr Simon says.
This sets it apart from its ice giant neighbour, Neptune.
"If you go to Neptune, its moons are not actually its original moons, they were captured."
It has extreme weather
Thanks to the planet's extreme tilt, it has extreme weather. Not that you'd realise that by looking at the images captured by the Voyager 2 spacecraft.
"It was just bland, blue, pretty, but nothing spectacular," Dr Simon says.
Part of that was actually a consequence of Voyager's cameras.
"They were not that advanced and they could not see red wavelengths," she says.
We also only got to see the planet's southern hemisphere during its summer.
"When Voyager flew by, one side was illuminated, we couldn't see the other side at all," she says.
If other planets such as Jupiter or Neptune are any indication, weather patterns are more pronounced at the equator, Professor Horner says.
"So when Voyager flew past Uranus, it was maybe when the weather was least interesting," he says.
In the 36 years since Voyager, we have glimpsed some of this weather through the lenses of the Keck Telescope and the Hubble Space Telescope.
These telescopes have revealed massive storms caused when regions that haven't been heated for 42 years warm up as the seasons change.
But all our existing telescopes, including the new James Webb Space telescope, are still limited in what they can tell us, Dr Simon says.
"These planets are still very far away, so we can see details [with a space telescope] clearly better than we could with a small telescope on Earth, but it's still not as good as getting there."
It's a giant blue ice slushy
Around four times the size of Earth, we think Uranus is a giant ball of dense fluid of "icy" materials – water, methane and ammonia — around a small rocky core.
Its atmosphere is hydrogen and helium mixed with significant amounts of ammonia and methane, which gives it its blue colour, as well as water and other gasses.
But we don't know exactly what these layers look like, Dr Maynard-Casely says.
Understanding more about this could help us work out why the planet is so cold.
"It is colder than Neptune, we know that it's putting out less heat than we expect," Dr Maynard-Casely says.
"Is there a layer within the interior that's stopping the heat from escaping it?"
What's going on in the layers could also help explain why the planet has a very strange magnetic field.
"Its magnetic field doesn't seem to originate right in the centre like the Earth and magnetic fields of most other planets," Dr Maynard-Casely says.
"It looks like the magnetic field is coming from this from the mantle, the bit around the core."
One hypothesis, she says, is that the water and ammonia in the layers is under high pressure, which is changing the subatomic particles within them.
"Putting a spacecraft into orbit would enable us to find a lot more about how the density changes through the planet," she says.
"It gives you a lot better idea if there are three layers … and then those transitions between them.
"Or are there lots and lots of layers? Or is it sort of just a gradual change all the way down to the middle?"
Its Shakespearean moons may be water worlds
Unlike other planets, whose moons are named after characters from Greek mythology, Uranus's 27 moons are named after the works of William Shakespeare and Alexander Pope.
And like Uranus, Voyager only gave us fleeting glances of parts of these small worlds, which have names like Ophelia, Cordelia, Bianca and Belinda.
"Because Uranus is tilted on its side, it automatically comes in on an almost polar orbit, which is not great for getting to all those satellites that are in orbit at the equator," Dr Simon says.
Yet we suspect some of them may be — or may have been — water worlds.
"It's incredible to think that something so far from the Sun can potentially have a habitable environment," Dr Simon says.
"It just kind of blows your mind."
Miranda — the fifth-largest moon named after the character in The Tempest — is covered with cracks and fissures.
"For a long time, Miranda was thought to be an object that was shattered and reconstructed from big lumps, but more recently people are thinking it's evidence of cryovolcanism," Professor Horner says.
"But to learn more about it, we need to get up there and spend time."
Miranda is odd, Dr Maynard-Casely agrees.
"It's the smaller of the round satellites, but it's got some really quite dramatic features.
"Are they something that's bumped into it, or are they actually about tectonic activity?
"It could also be that there's actually radiation damage on the surface."
Radiation damage from the Sun, Uranus itself, or from somewhere outside our Solar System, has the potential to change the structure of water into a glassy state known as amorphous ice.
"Because none of these moons have atmospheres, we do anticipate that there will be quite a lot of this amorphous ice on the surface," she says.
A mission for a new generation
It will take a while before Uranus is restored to its position as the "God of the Sky" (until then expect a couple more decades of jokes).
Because Uranus is so far away and takes 84 years to orbit our Sun, it is very tricky to get to.
"It's really the mission for the next generation of scientists because it is on such a long timescale," Dr Simon says.
If NASA can meet its 2031 or 2032 deadline, it will take 12 years for the mission to reach its destination using the gravitational pull of Jupiter to fling it out into the outer Solar System, Dr Simon says.
"It starts to get harder after that [deadline]. Then you can't use Jupiter and have to do Earth and Venus flybys," she says.
Not only will NASA send an orbiter to spend time flying around the planet and its moon, it will plunge a probe through the planet's atmosphere.
"If we think about what we knew about Jupiter and Saturn from the Voyager spacecraft, and then compare that with what we know from Galileo and Cassini, we've learnt a huge amount more," Professor Horner says.
"It's the difference between having a single short flyby, and having months or years of continual observations."
https://www.abc.net.au/news/science/202 ... /101023950
- Uranus, seen here in infrared light from the Keck Telescope, is surrounded by a fine ring and moons that circle the equator.(Supplied: Lawrence Sromovsky, University of Wisconsin-Madison/W.W. Keck Observatory)
- uranus.jpg (76.23 KiB) Viewed 542 times
Its name alone is the butt of jokes, and NASA's announcement last week that it wanted to target Uranus with a probe was a comedian's field day.
But planetary scientists are over the moon our seventh planet is finally going to get its day in the sun.
The fact that it's so far away from the Sun – 2.9 billion kilometres – is one of the reasons it has been so lonely and misunderstood.
Unlike its flashy siblings Jupiter and Saturn, Uranus has only had one visitor — a brief flyby by the Voyager 2 spacecraft in 1986, said Amy Simon, one of the NASA scientists who has been advocating for a mission to the planet.
"It's one of the strangest planets in the Solar System and yet we haven't been back there," Dr Simon said.
"This really is huge, unexplored territory."
Helen Maynard-Casely, an Australian planetary scientist at ANSTO who studies ice giant planets, agrees.
"It's just a shame that Uranus and Neptune have been ignored so much," Dr Maynard-Casely says.
"As soon as we start studying one of the two, it will reveal so much about the other one."
So let's see what makes this planet so cool (apart from the fact that at a very chilly minus-224 degrees Celsius, it holds the record for the coldest place in the Solar System).
It took 70 years to name (it could have been called George)
All the inner planets have been known since ancient times because they are easy to spot in the night sky, but Uranus was the first planet to be "discovered", and even then astronomers thought it was a comet or a star.
If William Herschel had his way in 1781, our seventh planet would have been called Georgian Sidus, or George's Star, after his patron King George III.
Seventy years later astronomers settled on Uranus.
While many people pronounce the planet as Ur-Anus, astronomers prefer to say Uran-us.
"I think there are many ways of pronouncing it but if you go for Ur-Anus, people snigger," says Jonti Horner, a planetary scientist at the University of Southern Queensland.
"It would have been a lot easier if Herschel had his way and it was called George."
But Uranus is much more regal. It was named after the Greek god of the sky, Ouranos, father of Saturn and grandfather of Jupiter.
Summer lasts for 42 years at the poles
Unlike all the other planets, Uranus is tipped on its side at an angle of 97.77 degrees.
"What that means is that it rolls along its orbit rather than spinning," Professor Horner says.
"It's a really very weird, very different place."
Its extreme tilt means that each pole continuously faces towards the Sun for 42 Earth years.
"Averaged through the course of the year, the poles get more sunlight and more energy than the equator, which is very different to other planets," Professor Horner says.
We don't know why the planet — and its bevvy of moons and rings that circle the equator — are on an angle.
One hypothesis, says Dr Simon, is that it was smashed into by something roughly the same size in the early Solar System.
But that doesn't explain how Uranus got its moons.
"It has all these small moons that are clearly in that same orbit and they had to have formed around the same time [as the planet]," Dr Simon says.
This sets it apart from its ice giant neighbour, Neptune.
"If you go to Neptune, its moons are not actually its original moons, they were captured."
It has extreme weather
Thanks to the planet's extreme tilt, it has extreme weather. Not that you'd realise that by looking at the images captured by the Voyager 2 spacecraft.
"It was just bland, blue, pretty, but nothing spectacular," Dr Simon says.
Part of that was actually a consequence of Voyager's cameras.
"They were not that advanced and they could not see red wavelengths," she says.
We also only got to see the planet's southern hemisphere during its summer.
"When Voyager flew by, one side was illuminated, we couldn't see the other side at all," she says.
If other planets such as Jupiter or Neptune are any indication, weather patterns are more pronounced at the equator, Professor Horner says.
"So when Voyager flew past Uranus, it was maybe when the weather was least interesting," he says.
In the 36 years since Voyager, we have glimpsed some of this weather through the lenses of the Keck Telescope and the Hubble Space Telescope.
These telescopes have revealed massive storms caused when regions that haven't been heated for 42 years warm up as the seasons change.
But all our existing telescopes, including the new James Webb Space telescope, are still limited in what they can tell us, Dr Simon says.
"These planets are still very far away, so we can see details [with a space telescope] clearly better than we could with a small telescope on Earth, but it's still not as good as getting there."
It's a giant blue ice slushy
Around four times the size of Earth, we think Uranus is a giant ball of dense fluid of "icy" materials – water, methane and ammonia — around a small rocky core.
Its atmosphere is hydrogen and helium mixed with significant amounts of ammonia and methane, which gives it its blue colour, as well as water and other gasses.
But we don't know exactly what these layers look like, Dr Maynard-Casely says.
Understanding more about this could help us work out why the planet is so cold.
"It is colder than Neptune, we know that it's putting out less heat than we expect," Dr Maynard-Casely says.
"Is there a layer within the interior that's stopping the heat from escaping it?"
What's going on in the layers could also help explain why the planet has a very strange magnetic field.
"Its magnetic field doesn't seem to originate right in the centre like the Earth and magnetic fields of most other planets," Dr Maynard-Casely says.
"It looks like the magnetic field is coming from this from the mantle, the bit around the core."
One hypothesis, she says, is that the water and ammonia in the layers is under high pressure, which is changing the subatomic particles within them.
"Putting a spacecraft into orbit would enable us to find a lot more about how the density changes through the planet," she says.
"It gives you a lot better idea if there are three layers … and then those transitions between them.
"Or are there lots and lots of layers? Or is it sort of just a gradual change all the way down to the middle?"
Its Shakespearean moons may be water worlds
Unlike other planets, whose moons are named after characters from Greek mythology, Uranus's 27 moons are named after the works of William Shakespeare and Alexander Pope.
And like Uranus, Voyager only gave us fleeting glances of parts of these small worlds, which have names like Ophelia, Cordelia, Bianca and Belinda.
"Because Uranus is tilted on its side, it automatically comes in on an almost polar orbit, which is not great for getting to all those satellites that are in orbit at the equator," Dr Simon says.
Yet we suspect some of them may be — or may have been — water worlds.
"It's incredible to think that something so far from the Sun can potentially have a habitable environment," Dr Simon says.
"It just kind of blows your mind."
Miranda — the fifth-largest moon named after the character in The Tempest — is covered with cracks and fissures.
"For a long time, Miranda was thought to be an object that was shattered and reconstructed from big lumps, but more recently people are thinking it's evidence of cryovolcanism," Professor Horner says.
"But to learn more about it, we need to get up there and spend time."
Miranda is odd, Dr Maynard-Casely agrees.
"It's the smaller of the round satellites, but it's got some really quite dramatic features.
"Are they something that's bumped into it, or are they actually about tectonic activity?
"It could also be that there's actually radiation damage on the surface."
Radiation damage from the Sun, Uranus itself, or from somewhere outside our Solar System, has the potential to change the structure of water into a glassy state known as amorphous ice.
"Because none of these moons have atmospheres, we do anticipate that there will be quite a lot of this amorphous ice on the surface," she says.
A mission for a new generation
It will take a while before Uranus is restored to its position as the "God of the Sky" (until then expect a couple more decades of jokes).
Because Uranus is so far away and takes 84 years to orbit our Sun, it is very tricky to get to.
"It's really the mission for the next generation of scientists because it is on such a long timescale," Dr Simon says.
If NASA can meet its 2031 or 2032 deadline, it will take 12 years for the mission to reach its destination using the gravitational pull of Jupiter to fling it out into the outer Solar System, Dr Simon says.
"It starts to get harder after that [deadline]. Then you can't use Jupiter and have to do Earth and Venus flybys," she says.
Not only will NASA send an orbiter to spend time flying around the planet and its moon, it will plunge a probe through the planet's atmosphere.
"If we think about what we knew about Jupiter and Saturn from the Voyager spacecraft, and then compare that with what we know from Galileo and Cassini, we've learnt a huge amount more," Professor Horner says.
"It's the difference between having a single short flyby, and having months or years of continual observations."
May you be in heaven half an hour before the devil know`s you`re dead!
Re: Astronomy, cosmology and space thread
The current overcast conditions may obscure this, but if you can find a clear spot it usually puts on a good show.
.............................................................................................................
Eta Aquarids Meteor Shower 2022
https://www.timeanddate.com/astronomy/m ... arids.html
May Meteor Shower
Also sometimes spelled as Eta Aquariid, the meteor shower is usually active between April 19 and May 28 every year.
edit add another link:
https://www.planetary.org/articles/your ... eor-shower
.............................................................................................................
Eta Aquarids Meteor Shower 2022
https://www.timeanddate.com/astronomy/m ... arids.html
May Meteor Shower
Also sometimes spelled as Eta Aquariid, the meteor shower is usually active between April 19 and May 28 every year.
- 47c4a4db716f4b73809f1a60f555b816.jpg (72.57 KiB) Viewed 519 times
https://www.planetary.org/articles/your ... eor-shower
May you be in heaven half an hour before the devil know`s you`re dead!