UK Spaceport, where?
Discussion
Eric Mc said:
The UK is not ideally placed for launching satellites into earth orbit. The vast bulk of satellites are launched in an easterly direction either parallel to the earth's equator or at an angle up to about 50 degrees of the earth's equator.
Launching to the east makes use of the earth's spin as this gives the launch vehicle a "free" couple of thousand miles an hour boost that does not have to be provided by rocket thrust. This obviously keeps your rocket smaller and cheaper or allows larger payloads to be orbited.
The free boost is best nearer to the equator so the UK is not as competitive when pitching for launches as (say) Baikanour, Cape Canaveral or Korou in French Guiana.
Obviously, launching from the UK in an easterly direction will, in most cases, take your rocket over inhabited land masses - which is not ideal.
Launching in a westerly direction would be safer but it is far from ideal. Rockets are launched on westerly orbits but only when the demands of the mission requires it, which is not often.
Polar orbits ARE feasible from the UK. A launch site in Cornwall could send rockets in a southerly path down over the Bay of Biscay, avoiding any land. However, these are busy shipping and air travel routes so that would work against that location.
If Britain wants a practical and attractive to customers launch site, I'd look at Ascension Island in the South Atlantic.
Yes that sums it up nicely. We're not particularly blessed geographically for the more favourable west-east launches.Launching to the east makes use of the earth's spin as this gives the launch vehicle a "free" couple of thousand miles an hour boost that does not have to be provided by rocket thrust. This obviously keeps your rocket smaller and cheaper or allows larger payloads to be orbited.
The free boost is best nearer to the equator so the UK is not as competitive when pitching for launches as (say) Baikanour, Cape Canaveral or Korou in French Guiana.
Obviously, launching from the UK in an easterly direction will, in most cases, take your rocket over inhabited land masses - which is not ideal.
Launching in a westerly direction would be safer but it is far from ideal. Rockets are launched on westerly orbits but only when the demands of the mission requires it, which is not often.
Polar orbits ARE feasible from the UK. A launch site in Cornwall could send rockets in a southerly path down over the Bay of Biscay, avoiding any land. However, these are busy shipping and air travel routes so that would work against that location.
If Britain wants a practical and attractive to customers launch site, I'd look at Ascension Island in the South Atlantic.
I was looking at how the Earth's effective rotational speed varies by latitude.
It's Cos (latitude in degrees) * 1038 for mph [or * 1670 for Km/h]
The Arianespace launch site in French Guyana is only 5 degrees north, so it's losing less than 4 mph over being at the equator itself. St Mawgan in Cornwall is 50 degrees north, so that's losing 371 mph over being at the equator. Not that it would be allowed to fire rockets eastwards over the UK of course.
Ascension island is 7.5 degrees south, so loses less than 9 mph over an equatorial launch. I suppose the main problem with Ascension is its sheer remoteness from a logistical point of view. Currently the island's runway is restricted for a couple of years due to potholes. Funnily enough, there's also an ESA tracking station on the island to track Ariane launches.
For the record, Cape Canaveral is at 28 degrees north and Baikonur at 45.5.
Beati Dogu said:
Eric Mc said:
Launching to the east makes use of the earth's spin as this gives the launch vehicle a "free" couple of thousand miles an hour boost that does not have to be provided by rocket thrust. This obviously keeps your rocket smaller and cheaper or allows larger payloads to be orbited.
The free boost is best nearer to the equator so the UK is not as competitive when pitching for launches as (say) Baikanour, Cape Canaveral or Korou in French Guiana.
Obviously, launching from the UK in an easterly direction will, in most cases, take your rocket over inhabited land masses - which is not ideal.
Launching in a westerly direction would be safer but it is far from ideal. Rockets are launched on westerly orbits but only when the demands of the mission requires it, which is not often.
The free boost is best nearer to the equator so the UK is not as competitive when pitching for launches as (say) Baikanour, Cape Canaveral or Korou in French Guiana.
Obviously, launching from the UK in an easterly direction will, in most cases, take your rocket over inhabited land masses - which is not ideal.
Launching in a westerly direction would be safer but it is far from ideal. Rockets are launched on westerly orbits but only when the demands of the mission requires it, which is not often.
Beati Dogu said:
Yes that sums it up nicely. We're not particularly blessed geographically for the more favourable west-east launches.
I was looking at how the Earth's effective rotational speed varies by latitude.
It's Cos (latitude in degrees) * 1038 for mph [or * 1670 for Km/h]
The Arianespace launch site in French Guyana is only 5 degrees north, so it's losing less than 4 mph over being at the equator itself. St Mawgan in Cornwall is 50 degrees north, so that's losing 371 mph over being at the equator. Not that it would be allowed to fire rockets eastwards over the UK of course.
Ascension island is 7.5 degrees south, so loses less than 9 mph over an equatorial launch. I suppose the main problem with Ascension is its sheer remoteness from a logistical point of view. Currently the island's runway is restricted for a couple of years due to potholes. Funnily enough, there's also an ESA tracking station on the island to track Ariane launches.
For the record, Cape Canaveral is at 28 degrees north and Baikonur at 45.5.
Are these speeds affected by the time of the year too? So, is it purely the Earth's spin that gives our rockets a boost, or does the speed that the Earth moves through space (orbiting the Sun) also affect it?I was looking at how the Earth's effective rotational speed varies by latitude.
It's Cos (latitude in degrees) * 1038 for mph [or * 1670 for Km/h]
The Arianespace launch site in French Guyana is only 5 degrees north, so it's losing less than 4 mph over being at the equator itself. St Mawgan in Cornwall is 50 degrees north, so that's losing 371 mph over being at the equator. Not that it would be allowed to fire rockets eastwards over the UK of course.
Ascension island is 7.5 degrees south, so loses less than 9 mph over an equatorial launch. I suppose the main problem with Ascension is its sheer remoteness from a logistical point of view. Currently the island's runway is restricted for a couple of years due to potholes. Funnily enough, there's also an ESA tracking station on the island to track Ariane launches.
For the record, Cape Canaveral is at 28 degrees north and Baikonur at 45.5.
If the spacecraft is intended to orbit the earth, then the earth's speed around the sun is of no significance.
If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
It would seem the scientific community and government does not agree as plans are being made for space flight from the UK, and I suspect the government would see developments before the public
The Space Industry Bill has been introduced into the House of Lords, marking the first step in the process to create new laws and a regulatory framework to enable exciting new technologies to operate safely from the UK.
https://www.gov.uk/government/news/introduction-of...
http://services.parliament.uk/bills/2017-19/spacei...
The Space Industry Bill has been introduced into the House of Lords, marking the first step in the process to create new laws and a regulatory framework to enable exciting new technologies to operate safely from the UK.
https://www.gov.uk/government/news/introduction-of...
http://services.parliament.uk/bills/2017-19/spacei...
Eric Mc said:
If the spacecraft is intended to orbit the earth, then the earth's speed around the sun is of no significance.
If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
Thanks Eric. If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
AshVX220 said:
Eric Mc said:
If the spacecraft is intended to orbit the earth, then the earth's speed around the sun is of no significance.
If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
Thanks Eric. If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
Maybe a more eloquent page from Nasa if you can't be bothered with the maths
https://solarsystem.nasa.gov/basics/chapter4-1
Please no need to thank me
Edited by Toaster on Thursday 6th July 15:02
Toaster said:
AshVX220 said:
Eric Mc said:
If the spacecraft is intended to orbit the earth, then the earth's speed around the sun is of no significance.
If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
Thanks Eric. If the spacecraft is travelling to another object that is in its own orbit around the sun such as a planet, asteroid or comet - or a moon around another planet, then the earth's speed around the sun will have some significance.
However, in those cases, of far more importance is that the earth needs to be in the optimal point in its own orbit around the sun to make the path of the probe the least demanding in energy and fuel.
Even taking that into account, many probes to other planets etc are dependent on gravity assist from another planet or moon. So taking all those factors into account, the actual speed of the earth's orbit around the sun drops down the priority list of considerations.
Maybe a more eloquent page from Nasa if you can't be bothered with the maths
https://solarsystem.nasa.gov/basics/chapter4-1
Please no need to thank me
Edited by Toaster on Thursday 6th July 15:02
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