Very different, take a look at this.
Orbit - Webb/NASA
'L2' Will be the James Webb Space Telescope's Home in Space
06.23.10
> View larger image
The five Lagrangian points for the Sun-Earth system are shown in the diagram below. An object placed at any one of these 5 points will stay in place relative to the other two. Credit: NASAWhen you ask an astronomer about the James Webb Space Telescope's orbit, they'll tell you something that sounds like it came from a science-fiction novel. The Webb won't be orbiting the Earth –instead we will send it almost a million miles out into space to a place called "L2."
L2 is short-hand for the second Lagrange Point, a wonderful accident of gravity and orbital mechanics, and the perfect place to park the Webb telescope in space. There are five so-called "Lagrange Points" - areas where gravity from the sun and Earth balance the orbital motion of a satellite. Putting a spacecraft at any of these points allows it to stay in a fixed position relative to the Earth and sun with a minimal amount of energy needed for course correction.
The term L2 may sound futuristic and mysterious, but the name actually honors a Mathematician born in 1736. The Lagrange points were named after the Italian-born mathematician and astronomer Joseph-Louis Lagrange, who made important contributions to classical and celestial mechanics. Lagrange studied the "three-body problem" (so-called because three bodies are orbiting each other) for the Earth, sun, and moon in 1764, and by 1772 he had found the solution; there are five stable points at which you could put an object and have it stay fixed in place relative to the other two.
In the case of L2, this happens about 930,000 miles away from the Earth in the exact opposite direction from the sun. The Earth, as we know, orbits the sun once every year. Normally, an object almost a million miles farther out from the sun should move more slowly, taking more than a year to complete its orbit around the sun. However, at L2, exactly lined up with both the sun and Earth, the added gravity of the two large bodies pulling in the same direction gives a spacecraft an extra boost of energy, locking it into perfect unison with the Earth's yearly orbit. The Webb telescope will be placed slightly off the true balance point, in a gentle orbit around L2.
The James Webb Space Telescope relative to the Hubble telescope's orbit around the Earth. Credit: NASA
Why send the Webb telescope all the way out to L2? When astronomers began to think about where the Webb telescope should be placed in space, there were several considerations to keep in mind. To begin with, the Webb telescope will view the universe entirely in infrared light, what we commonly think of as heat radiation. To give the telescope the best chance of detecting distant, dim objects in space, the coldest temperatures possible are needed.
"A huge advantage of deep space (like L2) when compared to Earth orbit is that we can radiate the heat away," said Jonathan P. Gardner, the Deputy Senior Project Scientist on the Webb Telescope mission and Chief of the Observational Cosmology Laboratory at NASA's Goddard Space Flight Center in Greenbelt, Md. "Webb works in the infrared, which is heat radiation. To see the infrared light from distant stars and galaxies, the telescope has to be cold. Webb's large sunshield will protect it from both Sunlight and Earthlight, allowing it to cool to 225 degrees below zero Celsius (minus 370 Fahrenheit)." For the sunshield to be effective, Webb will need to be an orbit where the sun and Earth are in about the same direction.
With the sun and the Earth in the same part of the sky, the Webb telescope will enjoy an open, unimpeded view of the universe. In comparison, the Hubble Space Telescope is in low-Earth orbit where it goes in and out of the Earth's shadow every 90 minutes. Hubble's view is blocked by the Earth for part of each orbit, limiting where the telescope can look at any given time.
The Spitzer Space Telescope, another infrared telescope, is in orbit around the sun and drifting away from the Earth. Spitzer is already more than 100 million kilometers (60 million miles) away from the Earth, and eventually its path will take it to the other side of the sun. Once we can no longer communicate with Spitzer that means it is at the end of its mission life.
> Click on image to view animation.
This animation shows the Webb Telescope spacecraft orbiting far from the Earth. Credit: NASA/Chris Meaney (HTSI)In contrast, a major perk of parking at L2 is the ease of communications. Essentially, the Webb telescope will always be at the same point in space. "We can have continuous communications with Webb through the Deep Space Network (DSN)," Gardner said. "During routine operations, we will uplink command sequences and downlink data up to twice per day, through the DSN. The observatory can perform a sequence of commands (pointing and observations) autonomously. Typically, we will upload a full week's worth of commands at a time, and make updates daily as needed."
Even before the Webb telescope, L2 has been known to astronomers as a good spot for space-based observatories. There are already several satellites in the L2 orbit, including the Wilkinson Microwave Anisotropy Probe, and the Herschel and Planck space observatories. But there's plenty of room for another neighbor, and the Webb telescope will be heading out to L2 in the near future.
The Webb telescope is a joint project of NASA, the European Space Agency and the Canadian Space Agency.
NASA -
'L2' Will be the James Webb Space Telescope's Home in Space
Receiving pictures from ISS (International Space Station)
I've briefly posted about this before, but here's a more detailed description of this process.
On special occasions, colour pictures are transmitted digitally each year from the ISS, typically between Christmas and the New Year. As ISS (in LEO) passes overhead, it's possible to receive these images with very simple equipment). Each picture takes about 3 minutes to transmit, with a 2-minute break between sending of images. That fits well into the period when the ISS is visible overhead, which at maximum elevation is only about 10 minutes between coming up over the horizon and then disappearing back down below the opposite horizon. High mountains nearby don't help for good signal reception! I seem to remember that the transmitter power on ISS is about 25 watts.
This year, ISS is sending out pictures from previous and possible future lunar projects. There are 12 images in total. At my new (maybe temporary) location in south-west Turkey, I decided to see if I could receive one or more of these images.
First I need some hardware and software:
- A simple half-wave wire dipole that's resonant on the operating frequency of 145.8 MHz. I would normally use something more sophisticated, but I had to leave my DIY 'sophisticated' antenna in Laos. So I used the wooden broom handle from my new house and taped two 45cm lengths of wire to it, then connected a length of satellite TV coaxial feed cable to the centre. I hoisted the broom handle about 4 metres into the air on a temporary fibreglass pole in my garden.
Next was the radio receiver. I use a simple 'dongle' receiver. To boost the gain of the signal, I use a small, wideband preamplifier. Both of these can be bought on AliExpress.
Here is the hardware, ready to plug into my laptop USB port.
Now for the software. The dongle radio uses a free software app called SDR Sharp. I downloaded the software and configured it for the correct receive frequency, modulation type etc.
Since the ISS is moving overhead, there is a doppler shift which alters the nominal frequency of 145.8 MHz. So I use another free piece of software called gpredict, which not only tracks when the ISS will be overhead (using Kepler data), but also calculates the doppler shift and sends the correct frequency to SDR Sharp. So my software will always be on exactly the right frequency as the ISS passes over me.
Finally, I need some software to decode the digital signal and convert this into a visible image. MMSSTV is used, whish is a popular program amongst radio amateurs to receive images sent by other hams.
With all this set up, all I need to do is to wait for the ISS to appear over my location
The n2yo.com website gives a list of all passes over my location. Gpredict is running all the time on my laptop, so I can receive signals even when asleep...
The first couple of passes over me were at a very low elevation of about 5 degrees, and my local mountains blocked the signal..
But at 9.53am this morning, there was a pass at a maximum elevation of 16 degrees. I expected to receive only a weak signal, but got a surprise when an almost-perfect picture was received direct from the ISS! Clearly my broomstick antenna was doing a.. er ... stellar job
Here are some screengrabs:
The image with the world map is gpredict, with it's control panel window placed over the map so you can see both windows. You can see the current footprint of ISS which is over New Zealand. The control window shows the next AoS (Acquisition of Satellite) in 54 minutes, together with the doppler frequency being sent to SDR Sharp (of course, the signal from the ISS can't be received since it's below the horizon).
The SDR Sharp software looks like this, ready to receive the signal.
Here is MMSSTV, after receiving and decoding the digital signal from SDR Sharp.
Finally, here are some of the images from the ISS that I managed to receive over a few passes.
I'll try for some more images over the next few days
Groping women when you're old is fine - everyone thinks you're senile
Elon Musk criticised after China space complaint to UN
Elon Musk is facing a social media backlash after China complained that its space station was forced to avoid collisions with satellites launched by his Starlink Internet Services project.
The country's space station had two "close encounters" with Starlink satellites, Beijing claimed.
China's complaints, lodged with the UN's space agency, have not yet been independently verified.
Starlink is a satellite internet network operated by Mr Musk's SpaceX.
Mr Musk is well known in China even as his electric carmaker Tesla comes under growing scrutiny from regulators.
The incidents occurred on 1 July and 21 October, according to a document submitted by China this month to the United Nations Office for Outer Space Affairs.
"For safety reasons, the China Space Station implemented preventive collision avoidance control," Beijing said in the document published on the agency's website.
SpaceX did not immediately respond to a request for comment from the BBC.
After the complaint was made public, Mr Musk, Starlink and the US were heavily criticised on China's Twitter-like Weibo microblogging platform.
One user described Starlink's satellites as "just a pile of space junk".
The satellites are "American space warfare weapons" and "Musk is a new 'weapon' created by the US government and military", others said.
Another posted: "The risks of Starlink are being gradually exposed, the whole human race will pay for their business activities."
Scientists have voiced concerns about the risks of collisions in space and called on world governments to share information about the estimated 30,000 satellites and other space debris that are orbiting earth.
SpaceX has already launched almost 1,900 satellites as part of the Starlink network, and plans to deploy thousands more.
Last month, the US space agency NASA abruptly postponed a spacewalk from the International Space Station over concerns about space debris.
https://www.bbc.com/news/business-59806499
I suspect that both will remain being considered exceptional for their time and ability.
A very important point, I agree.
You are an exceptional engineer and jack of all trades.
Sauce for the Goose and the Gander.
Highlights of China's space achievements in 2021
By: Global Times | Published: Dec 30, 2021 12:31 AM
Space launches exceed 50 times, long March carrier rocket embarks on 400th mission, the second country to land a rover on Mars…In the voyage of space, China never stops.
A five minute video available here:
http://1253985869.vod2.myqcloud.com/.../v.f100030.mp4
A tray full of GOLD is not worth a moment in time.
Exclusive: China, Russia to sign new 5-year space cooperation program, build intl lunar station by 2035: Roscosmos
By Deng Xiaoci and Fan Anqi
Published: Dec 29, 2021 09:26 PM Updated: Dec 29, 2021 09:22 PM
"China and Russia will sign a new space Cooperation Program for 2023-2027 next year, which will include a plan to create an open and inclusive International Lunar Research Station (ILRS) by 2035, Russia's national space agency Roscosmos told the Global Times in an exclusive interview.
The new program will also include plans to support the development of the ground segment of the two countries' national satellite systems, Russia's GLONASS and China's BeiDou Navigation Satellite System (BDS) to be installed next year, as well as a slate of exciting projects Roscosmos and the China National Space Agency (CNSA) will work on in the coming decades as the two countries join forces to achieve new heights in the sphere of space exploration"
continues at:
Exclusive: China, Russia to sign new 5-year space cooperation program, build intl lunar station by 2035: Roscosmos - Global Times
The source ? The language? The facts?
Chinese AI satellite takes ultra-high res images from orbit at speeds ‘never before seen’
By Jon Rogers, The Sun December 29, 2021 11:24am
Attachment 80532
"China has developed a powerful AI satellite capable of taking hi-res images of cities in a matter of seconds.
Beijing-3, a small one-ton commercial satellite, can take images clear enough to be able to identify a military vehicle on the street and tell what type of weapon it might be carrying, according to researchers.
The satellite was launched by China in June and performed an in-depth scan of the central San Francisco Bay area, covering 1,470 square miles, the journal Spacecraft Engineering reports.
Most satellites observing the Earth must be stable when taking image because altitude control mechanisms can produce vibrations that blur the images.
But in the Chinese experiment on June 16, the satellite was able to change the angle of its camera’s line of sight to the ground when passing over the US.
The movement meant it could capture a larger area than satellites have been previously able to.
The pictures were taken at an altitude of 310 miles and had a resolution of 50 centimeters per pixel with the test showing the satellite could take images while its body was twisting at up to 10 degrees per second, a speed not seen on a satellite before.
“China started relatively late on agile satellite technology, but achieved a large number of breakthroughs in a short period of time,” said project lead scientist Yang Fang from the DFH Satellite Company writing in a paper published in the domestic peer-reviewed journal Spacecraft Engineering this month.
“The level of our technology has reached a world-leading position.”
According to Yang, the Beijing-3 is the most nimble satellite ever seen and could be one of the most powerful Earth observation satellites ever built.
A satellite in the Earth’s lower orbit could normally observe a straight, narrow strip of area beneath it and would have to circle the Earth several times, or work with other satellites, to cover a region of interest.
Due to Beijing-3’s abilities, it was able to carry out some tasks previously considered technically impossible.
It was able to take images of the 6,300km-long Yangtze River between the Tibetan plateau and the East China Sea, in just one fly-by, according to Yang and her colleagues.
Military uses
The new technology could also have military uses as it can detect the presence of certain targets and relay the photos to control on the ground.
The Beijing-3’s response time is 2-3 times faster than the United States’ WorldView-4, currently the most advanced Earth observation satellite, according to Yang.
The Chinese satellite has a scanning band of 23km compared to the WorldView-4 which is 13km.
The WorldView-4 does have one advantage over its Chinese counterpart, the US satellite can take slightly more detailed images with a resolution of 30 centimeters per pixel.
While that is not sharp enough to read a car’s number plate it is sharp enough to reveal a military vehicle’s make and model which could be used to estimate its fire power.
However, when the WorldView-4 adjusted its position it could experience vibrations, reducing the quality of the images produced.
Yang claimed the new Beijing-3 was built on new platform known as CAST3000E which would lead to a new generation of Chinese satellites which were small but had a high performance.
AI control
The new platform carries solar panels with a unique structure that stop them shaking when the satellite turned quickly.
Equipment like telescopes and antennas were also designed using new technology, such as AI control, to protect the satellite from the physical impact caused by rapid movement.
The Chinese satellite is said to be able to store one terabyte of images and beam data to the ground at the rate of one gigabyte per second, faster than any US satellite.
Qi Yimin, a sales manager for DFH Satellite Company in Beijing, said in separate paper in the same journal this month that while China commercial satellite industry was still in the initial stages of development most of the country’s satellite imaging products served government or military users.
This article originally appeared on The Sun and was reproduced here with permission."
Chinese AI satellite takes ultra-high res images from orbit at speeds ‘never before seen’
A two-minute video, in Chinese, is here:
China’s nimble Beijing-3 satellite does unprecedented rapid scan of San Francisco | South China Morning Post
Some news about James Webb telescope.
So far deployment is moving forward well. They just have completed the most tricky part, deployment of the 5 layers of sun shield. NASA people working on it are relieved. But still a lot of work ahead.
https://twitter.com/NASAWebb/status/1478412564983959553
Deployment of James Webb telescope is complete. Full success so far. Now it is still 5 months until it is ready to operate. Reach its target position, which requires another burn of the engines. Cooling down the mirrors and sensors which takes a few months, then fine adjusting of the mirror segments. Presently some adjustment is done as proof the mechanisms work but fine adjustment can be done only once the mirrors are cooled down to operational temperature.
https://twitter.com/NASAWebb/status/1479880178021060609
A picture of an engineering model in the state the real James webb mirror has in space.#NASAWebb is fully deployed! Partyknaller
With the successful deployment & latching of our last mirror wing, that's:
50 major deployments, complete.
178 pins, released.
20+ years of work, realized.
Next to #UnfoldTheUniverse: traveling out to our orbital destination of Lagrange point 2!
"don't attribute to malice what can be adequately explained by incompetence"
Learned their lesson eh?fine adjusting of the mirror segments
We can hope so. Remember the Hubble mirror was ground and polished perfectly to specs. Unfortunately the specs were wrong. Of course tests were performed to the same wrong specs, which means, the mistake was not found until operational in orbit.
With segmented mirrors fine adjustment of placing each segment is always necessary. That fine adjustment can only be done when the telescope is at operational temperature, extremely cold. Let's hope the adjustment mechanism works at that temperature.
^ One of the most interesting operations will be the study of bio-data from exoplanet's atmospheres to see if there are any telltale bio-signatures of life on those planets.
Is there an estimated distance that it can study the biodata of exoplanets in lightyears? For example, can it study this for exoplanets within say 10,000 lightyears away, or 100,000 LY's away (the size of the Milky Way galaxy), or in other galaxies?
Cheers.
I'd laugh if it landed on some chinky kit, after them whingeing and all.
A SpaceX rocket is on collision course with the moon after hurtling through space for seven years.
The booster launched in Florida in February 2015 as part of a mission to send space weather satellite on a long-range mission.
The spent Falcon 9 rocket stage is on course to hit the Moon in March.
The rocket’s second stage was high enough that it did not have enough fuel to return to Earth's atmosphere.
It also lacked the energy to escape the gravity of the Earth-Moon system, so it has been following a chaotic orbit since February 2015 and experts have now revealed it is on a collision course with the moon.
Space object tracker Bill Gray has said he believes the four-tonne object will strike the far side of the moon, near its equator, on March 4.
It is expected to impact the Moon at a velocity of about 2.58 km/s - over 3,500 mph.
The details are unclear and there will be slight alterations to its orbit. Mr Gray wrote: “These unpredictable effects are very small.” He said the precise time and location of the impact could change.
Four-tonne Space X Falcon 9 rocket on course to hit the Moon 'in March' - LBC
A mysterious spinning object has been spotted in the Milky Way that is unlike anything seen before, scientists say.
Estimated to be around 4,000 light-years from Earth, researchers believe it could belong to a new class of slowly rotating neutron star with an ultra-powerful magnetic field that can be detected by radio telescopes.
The object, first discovered by an Australian university student working on his undergraduate thesis, has been observed to release a huge burst of radio energy for a whole minute every 18 minutes. The observation is known as a “transient” – which refers to an object that periodically releases brief flashes of radio signals, as if it is switching on and off in space.
Objects that pulse energy in the Universe are often documented, but researchers say an object that turns on for a full minute is highly unusual.
Natasha Hurley-Walker, who led the team at the International Centre for Radio Astronomy Research (ICRAR) at Curtin University, described the discovery as “spooky”.
"[It] was appearing and disappearing over a few hours during our observations,” she said.
“That was completely unexpected. It was kind of spooky for an astronomer because there's nothing known in the sky that does that.”
The team is now working to understand what they have found but ICRAR said they were able to establish that the object is incredibly bright and has an extremely strong magnetic field.
Scientists believe the object could be a neutron star or a white dwarf – a term used for the remnants of a collapsed star.
"More detections will tell astronomers whether this was a rare one-off event or a vast new population we'd never noticed before," Dr Hurley-Walker said.
"I'm looking forward to understanding this object and then extending the search to find more.”
New Milky Way discovery as 'spooky' spinning object uncovered by astronomers - World News - Mirror Online
The next post may be brought to you by my little bitch Spamdreth
Spooky cos we don’t know. Well done to the undergrad!
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