News & Press

Perseid meteor shower

Fri, 12 Aug 2022 15:07:00 GMT

The Perseid meteor shower is peaking on 12-13 August

Persend meteors may been seen between 17 July and 24 August this year; there could be up to 150 seen per hour.

The meteors are debris from the Swift-Tuttle comet hitting the Earth's atmosphere at between 7 and 45 miles per second; smaller meteors vaporise and leave behind a bright trail but larger ones can explode as fireballs. There could be up to 150 meteors seen per hour.

The shower is named 'Perseids' as the meteors seem to originate from the constellation of Perseus - the 'radiant'.

This year it is unfortunate that the peak coincides with a large full moon - as the meteors can appear anywhere in the sky, it is best to look away from the moon and away from other bright lights; from midnight to 0530 is advised as the best time.

Further details from the Royal Observatory

Contract for a renewed EGNOS

Mon, 27 Jun 2022 21:16:00 GMT

Thales Alenia Space has signed a new contract with the EU Agency for the Space Programme (EUSPA) to deploy a new version of the European Geostationary Navigation Overlay Service (EGNOS).

Since 2011, EGNOS has supported all modes of transport with a GPS overlay, and this Safety of Life service has in particular made the aviation sector safer and more efficient; European operators have made airports more accessible without having to install landing aids. Sadly, since leaving the EU, UK has been legally excluded from the EGNOS service.

Thales Alenia Space will provide EUSPA with the new version of EGNOS (V243), provided by new Navigation Land Earth Station (NLES) technology in NLES-G3. This will be integrated with a new geostationary satellite 'GEO3', which will further enhance EGNOS performance. The improved system is scheduled to become operational in 2024.

Further details from Thales Alenia Space

Resilient PNT for UK?

Tue, 14 Jun 2022 09:03:00 GMT

Since leaving the EU, the UK has ceased to be part of the Galileo satnav system, and with that has lost regulated use of the European Geostationary Navigation Overlay Service (EGNOS) safety of life (SOL) services.

But a national team of companies is broadcasting a satellite navigation signal to explore the creation of a sovereign national capability in resilient positioning, navigation and timing (PNT) for aviation and maritime use - UK Space-Based Augmentation System (UKSBAS).

The team is led by UK-based Inmarsat, world leader in global mobile satellite comms, working with British partners Goonhilly Earth Station Ltd from Cornwall and Nottingham-based GMVNSL. They are delivering UK Space Agency-funded tests with the European Space Agency (ESA) through the latter’s Navigation Innovation and Support Program (NAVISP).

The augmentation signal, being broadcast in coordination with the US Federal Aviation Administration (FAA), ESA and the EU Space Programme Agency (EUSPA), is now stable, enabling on-going testing and validation by industry, regulators and users.

The augmentation signal is transmitted from Goonhilly to Inmarsat's I-3 F5 satellite, launched in 1998. It is important to note that this demonstration is for a signal-in-space and provision of regulated services for the UK is beyond the scope of the current project.

Details from Inmarsat

Geomagnetic storm sees satellites burn up

Thu, 10 Feb 2022 17:47:04 GMT

3 February saw SpaceX launch 49 Starlink internet satellites into low-Earth orbit; but many have already burnt out.

A geomagnetic storm during the following day, 4 February, caused substantially increased density of the Earth's atmosphere, and hence the drag experienced by the still-low satellites. As a result, up to 40 of the spacecraft are expected to have burnt out within a couple of weeks.

The satellites were launched into a 53.2º inclined orbit, so observers between around 53ºN and 53ºS might witness them burning.

The earliest record of a solar flare impacting Earth was the ‘Carrington Event’ of 1859, which disrupted telegraph comms as well as causing fires due to discharges from lines. Many later reports have been noted, with at least 3 this century, causing loss of both comms and navigation signals.

Further details and image from Space.com

NASA’s James Webb Space Telescope launched

Sun, 26 Dec 2021 18:47:37 GMT

The launch took place from the European Space Centre at Kourou, French Guiana, at 1220 UTC on 25 December.

The Arianespace Ariane 5 rocket performed as scheduled, shedding its 2 boosters and payload fairing, then jettisoning its main stage and finally fully separating from the payload at ~27 minutes into the flight - releasing the observatory at an altitude of ~870 miles (1,400 km).

By day 2 we have seen automatic deployment of the solar panels to provide power, and the high-rate antenna for transmission of data back to Earth. This will be followed by deployment of the huge mirror.

With a couple of course corrections, after ~29 days from launch the telescope should be in its desired orbit at a range of ~1 million miles (1.6 million km) from Earth.

The sensor comprises 18 hexagonal mirrors, making a massive reflector of 21 ft (6.5 m) diameter. The mirrors require 132 actuators and motors and complex back-end software to form the final mirror, and the whole device had to be folded to fit into the payload fairing - and unfolded in space.

Using infrared sensors, the telescope will become the largest and most powerful observatory ever built, allowing astronomers to investigate the farthest parts of the universe.

President Biden offered his congratulations to the team: ”Congratulations NASA and all who made today's launch of the James Webb telescope possible. Webb is a shining example of the power of what we can accomplish when we dream big. We've always known that this project would be a risky endeavour, but with big risk comes big rewards."

Details and image from NASA

UK satnav augmentation system proposed

Thu, 9 Dec 2021 18:55:13 GMT

UK-based Inmarsat is working on a UK Space Agency-funded project with the European Space Agency (ESA), plus partners Goonhilly Earth Station Ltd and GMV NSL of Nottingham, to deliver the first UK-generated satnav overlay.

By repurposing a transponder from the Inmarsat-3 F5 (I-3 F5) satellite, the UKSBAS project will provide an overlay signal to augment GPS, refining the precision from a few metres to a few centimetres and confirming its legal usability for safety-critical applications such as aircraft landing and ships berthing.

This is required because, since leaving the EU, the UK no longer has access to the European Geostationary Navigation Overlay Service (EGNOS) Safety-of-Life services and is now not involved in the Galileo programme.

I-3F5 is in geosynchronous orbit at 54°W, ensuring that its signal covers the UK as part of its Atlantic Ocean region service overlay. The satellite was manufactured by Lockheed Martin and launched in 1998.

Further details from UKSpace

Successful Galileo launch

Sun, 5 Dec 2021 17:00:27 GMT

Galileo satellites 27/28 were launched on 5 December from Europe’s Spaceport in French Guiana.

This was the 11th operational Galileo launch over 10 years, with the current Initial Services having been declared in 2016.

The Soyuz launcher lifted off after a 2-day delay at 0019 UTC on 5 December, and the Fregat upper stage released the 715 kg satellites into their target orbits of ~23,525 km altitude 3h 54m later. Now the Launch and Early Operations Phase (LEOP) will involve inboard thrusters positioning the craft for some weeks whilst onboard systems are checked out for operational use.

These satellites are the first pair of the remaining 12 Galileo first-generation satellites, which are an improved version of the existing Full Operational Capability (FOC) design. Each is manufactured and tested by OHB in Germany, with the navigation payloads designed and built by Surrey Satellite Technology Ltd (SSTL) in UK.

Further details from ESA

Two Galileo satellites scheduled for launch

Tue, 23 Nov 2021 17:21:53 GMT

Galileo satellites 27/28 should be launched on a Soyuz carrier at 0031 UTC on 3 December from Europe’s Spaceport at Kourou, French Guiana.

This Galileo launch is the first of a series of 6 scheduled launches, each carrying 2 satellites. The recently-formed EU Agency for the Space Programme (EUSPA) will oversee the Launch and Early Orbit Phase (LEOP), which covers launch of the spacecraft, travel into correct orbits and gradual switching-on of the spacecraft to test core satellite elements.

LEOP should last ~10 days, seeing the satellites placed in drift start manoeuvres to inject them into target positions in medium-Earth orbits (MEO) of 23,222 km. There are currently 21 Galileo spacecraft operational plus 5 others in orbit but unavailable.

Further details from EUSPA

Successful QZSS launch

Sun, 31 Oct 2021 10:07:40 GMT

The past week has seen an addition to the Japanese Quasi-Zenith Satellite System.

The H-2A rocket lifted off from the Tanegashima Space Center, Japan, at 0219 UTC on 26 October. Mitsubishi Heavy Industries confirmed ~28 minutes after liftoff that the satellite had successfully separated from the rocket's upper stage.

The primary purpose of QZSS is to increase the availability of GPS in the numerous urban canyons and mountainous areas in Japan where only satellites at very high elevations can be seen.

There have been 4 satellites (QZS-1 to -4) in the constellation since 2018, one in geosynchronous equatorial orbit (GEO) and 3 in quasi zenith orbits (QZO), all around the Japanese longitude. This launch of QZS-1R, is to replace QZS-1, launched in 2010. It is planned to have 7 satellites in the constellation by 2024.

Using GPS and their own frequencies, the system claims public basic PNT accuracy of <10 m, with SBAS providing a sub-meter level augmentation service (SLAS) of <1 m and centimeter level augmentation service (CLAS) of <10 cm.

Further details from qzss.go.jp

Withdrawal of EGNOS for UK users

Sun, 11 Jul 2021 15:41:56 GMT

The Institute's President has warned of the effects of losing EGNOS.

“The UK’s precipitous withdrawal from statutory agreements on the use of the European Geostationary Navigation Overlay Service (EGNOS) will adversely impact several transportation systems” warned Cynthia Robinson OBE, as she assumed the role of President of the Royal Institute of Navigation.

“Some UK regional airports have invested significantly in EGNOS, but the legislation underpinning its Safety-of-Life (SoL) service was withdrawn on 25 June 2021. The signals will still be transmitted by EGNOS satellites, but any pilot tempted to use these in the UK will no longer be indemnified should an accident or incident occur”, she advised.

“The EGNOS system not only improves accuracy in certain situations and locations but, importantly, quickly indicates any malfunction of GPS satellites”, added Cynthia. “Humans tend to believe implicitly the position they see on a screen and forget that the signals may have become corrupted en route from distant satellites”.

“The recent withdrawal of the legal indemnity for aviation EGNOS use in the UK could ultimately affect ships, autonomous vehicles and beyond visual line-of-sight (BVLOS) drones as well, unless a replacement solution can be secured quickly. The shipping industry will need to consider appropriate solutions for UK waters, as future maritime EGNOS Safety-of-Life services will no longer be made available to the UK in 2023. Possible future wider EGNOS V3 SoL services overlaying GPS and Galileo will also be denied to the UK”, warned the President.

“The Royal Institute of Navigation is working closely with the UK government on the implications of the loss of the EGNOS augmentation Safety-of-Life services, as well as advising on how best to build resilience, integrity and improved security into the positioning and navigation technologies that affect just about every aspect of our modern lives” concluded Cynthia Robinson.

For further information, please contact Clare Stead, RIN Communications Officer, at comms@rin.org.uk

Successful GPS launch

Thu, 17 Jun 2021 18:29:08 GMT

The 5th GPSIII satellite has been launched from Cape Canaveral.

The launch of GPSIII-05 took place at 1609 UTC (1209 local) on 17 June from Space Launch Complex-40, using a SpaceX Falcon 9 reused booster, which itself returned safely.

GPSIII-05 has become SVN-78, using code PRN-11 in the constellation’s D plane. The position is currently occupied by SVN-61, which itself is to be moved elsewhere in the D plane. As a result of these moves, SVN-46, launched into the D plane in October 1999, will be removed from service after over 20 years - more than 12 years beyond its designed service life.

The satellite was deployed at ~1h 30m after launch and will eventually use its own propulsion to circularise its orbit. Space Force state that they will be performing an extended navigation test with SVN-78/PRN-11, so the satellite is not expected to be set healthy to users until sometime in September 2021.

The launch may be seen at YouTube

New EU space regulator

Mon, 17 May 2021 17:08:29 GMT

The EU has brought all space activities under one regulating body - the EU Agency for the Space Programme (EUSPA).

EUSPA replaces the European Global Navigation Satellite Systems Agency (GSA), covering Galileo and EGNOS, and will also include oversight of the EU’s Earth observation programme, Copernicus, and the EU’s forthcoming Governmental Satellite Communications Programme (GOVSATCOM). The European Space Agency (ESA) will remain a major partner in the technical and operational implementation of the EU space programme, but will remain independent of EUSPA.

The European Commission proposed the formation of EUSPA in mid-2018, but it was not until December 2020 that agreement was reached between the European Parliament and Council on the Programme. And it was on 28 April 2021 that the European Parliament approved the final update of the programme, allocating a €14.8 (£12.7, $18.0) billion budget.

Further details from the European Parliament

Successful GPS launch

Fri, 6 Nov 2020 15:11:56 GMT

SpaceX has launched the fourth GPS III from Cape Canaveral.

GPS III-SV04 was launched at 2324 UTC (1824 local) on 5 November. The launch had been attempted on 2 October, but a technical problem with the launch vehicle caused an abort with just 2 seconds to go.

Nine minutes after launch, the Falcon 9 rocket's first stage landed back on one of SpaceX's 2 drone ships; it will be used for further launches. The 2nd stage shut down and separated after ~1h 29m. A short burst from the 3rd stage then placed the satellite into an elliptical orbit for it to position itself in its circular orbit at 12,550 miles (22,200 km), inclined at 55º. III-04 will become SVN-77/PRN-14, replacing SVN-44/PRN-28 in the B plane at slot 03.

SV05 is complete and scheduled for launch early in 2021. Lockheed Martin have a further 5 satellites in test or build and are contracted to build a further 22 follow-on GPS IIIF spacecraft.

GPS III satellites have a planned life of 15 years and are designed to be forward- and backward-compatible, allowing them to fully adapt to the future whilst remaining fully usable with previous generations of spacecraft. They also transmit the L1C, L2C and L5 signals and are claimed to be 3-times more accurate than their predecessors, with 8-times improved anti-jam capability.

Details from Spaceflight Now

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CGSIC 2020 papers available

Mon, 2 Nov 2020 17:40:50 GMT

Papers from the 2020 US Civil GPS Service Interface Committee meeting are available on-line.

The virtual meeting, held on 21 & 22 September, comprised 2 Plenaries plus sessions on: International, Timing and Surveying, Mapping & Geosciences.

The delivered papers are current and authoritative and can be seen on YouTube; most are also downloadable as PDFs. They can be found at GPS.gov

Successful GLONASS launch

Mon, 26 Oct 2020 23:27:07 GMT

GLONASS-K 15L satellite was launched from Plesetsk at 2209 Moscow time (1909 UTC) on 25 October 2020.

The Russian military have reported that the 3-stage launch was successful. The launch of this third updated ‘K’ satellite had been scheduled for March 2020 but had been delayed by a series of technical issues.

GLONASS comprises 24 operational spacecraft in 3 circular medium earth orbits (MEO) at ~19,100 km (~11,900 miles) inclined at 64.8º. In addition to 24 satellites currently operational, there is an additional one in each of flight test, maintenance and spare - now joined by 15L in the commissioning phase.

Further details from the Information and Analysis Centre for PNT

Watch the Orionid meteor shower

Tue, 20 Oct 2020 16:18:13 GMT

The annual Orionid meteors should peak in the night sky from 20 to 22 October.

If the sky is clear, the meteors should be best seen after midnight, when the Moon has set. There could be up to 20 per hour. They appear to originate from the club of the constellation Orion - hence the name - but radiate in all directions.

The meteors stem from Comet Halley, being debris - left behind by the comet - burning up in the Earth’s atmosphere. They vaporise at ~60 miles (~100 km) above Earth’s surface, travelling at ~41 miles (~66 km) per second.

Further details from EarthSky

UK Government to explore new ways of delivering satnav

Sat, 26 Sep 2020 21:18:06 GMT

The Government has announced that it will explore new options for a national satellite navigation and timing capability programme to support critical infrastructure.

The 24 September announcement explains that the Space-Based Positioning Navigation and Timing Programme (SBPP) ‘Will explore new and alternative ways that could be used to deliver vital satellite navigation services to the UK which are critical for the functioning of transport systems, energy networks, mobile communications and national security and defence, whilst boosting the British space industry and developing the UK’s own capabilities in these services’.

The SBPP will follow the work of the UK’s GNSS programme, which is due to conclude at the end of September. This GNSS programme had developed plans for a conventional satellite system as an alternative to GPS or Galileo. The programme will now be reset as the SBPP to ‘Build on this work to consider newer, more innovative ideas of delivering global satnav and secure satellite services to meet public, government and industry needs’.

The statement explains that SBPP could include technology that supports people’s everyday lives, such as emergency services to locate incidents, financial services to regulate stock market exchanges or energy networks to ensure households receive power. Satellite navigation systems are also necessary for unlocking future technologies such as driverless cars, smart cities and artificial intelligence – transforming the way people live, work and travel.

The statement concludes ‘Capitalising on the ingenuity of British businesses and academics, the programme will explore the use of different kinds of satellites at various levels of orbit by exploiting technologies offered by companies at the cutting-edge of innovation such as OneWeb, Inmarsat and Airbus’.

Further details from www.gov.uk

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New mailThe Government has announced that it will explore new options for a national satellite navigation and timing capability programme to support critical infrastruct

New WAAS satellite launched

Mon, 17 Aug 2020 11:01:16 GMT

The satellite, launched on 15 August, includes a replacement receiver/transmitter for GPS Wide Area Augmentation System (WAAS) corrections.

Ariane 5 Flight VA253 was launched from the Guiana Space Centre, Kourou, at 2204 UTC on 15 August. The heaviest ever Ariane launcher carried 3 satellites: BSAT-4a for direct-to-home television broadcasting over Japan; MEV-2, a satellite servicing vehicle designed to dock with satellites in orbit; and Intelsat’s Galaxy 30 UHD video distribution/broadcast and broadband satellite, including WAAS, to cover North America.

The 3-satellite payload was placed in a geostationary transfer orbit (GTO) and ultimately the 2 comms satellites will be positioned in geosynchronous equatorial orbits (GEO). Galaxy 30, carrying the WAAS equipment, will be placed at 125ºW longitude - supplementing 2 other GEOs.

The WAAS satellite-based augmentation system (SBAS) is compatible with the European Geostationary Navigation Overlay Service (EGNOS), Indian GPS Aided Geo Augmented Navigation (GAGAN) and the Japanese Multi-functional Satellite Augmentation System (MSAS). All use a network of ground-based reference stations to determine real-time GPS errors, which are sent to master stations which relay correction messages via the SBAS satellites. The corrections are transmitted to receivers via GPS frequency and format.

The FAA WAAS accuracy requirements (95%) for an aircraft instrument runway approach down to 200 ft - Localizer Performance with Vertical guidance (LPV-200) - is 16m horizontal and 4 m vertical; actual performance has been 0.7m horizontal and 1.2m vertical.

Further details from the FAA

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New mailThe satellite, launched on 15 August, includes a replacement receiver/transmitter for GPS Wide Area Augmentation System (WAAS) corrections.

Ariane 5 Flight VA253 was launched from the Guiana Space Centre, Kourou, at 2204 UTC on 15 August. The heaviest ever Ariane launcher carried 3 satellites: BSAT-4a for direct-to-home television broadcasting over Japan; MEV-2, a satellite servicing vehicle designed to dock with satellites in orbit; and Intelsat’s Galaxy 30 UHD video distribution/broadcast and broadband satellite, including WAAS, to cover North America.

The 3-satellite payload was placed in a geostationary transfer orbit (GTO) and ultimately the 2 comms satellites will be positioned in geosynchronous equatorial orbits (GEO). Galaxy 30, carrying the WAAS equipment, will be placed at 125ºW longitude - supplementing 2 other GEOs.

The WAAS satellite-based augmentation system (SBAS) is compatible with the European Geostationary Navigation Overlay Service (EGNOS), Indian GPS Aided Geo Augmented Navigation (GAGAN) and the Japanese Multi-functional Satellite Augmentation System (MSAS). All use a network of ground-based reference stations to determine real-time GPS errors, which are sent to master stations which relay correction messages via the SBAS satellites. The corrections are transmitted to receivers via GPS frequency and format.

The FAA WAAS accuracy requirements (95%) for an aircraft instrument runway approach down to 200 ft - Localizer Performance with Vertical guidance (LPV-200) - is 16m horizontal and 4 m vertical; actual performance has been 0.7m horizontal and 1.2m vertical.

Further details from the

Annual Perseid meteor shower

Mon, 10 Aug 2020 21:06:11 GMT

The Perseid shower peaks on the morning of 12 August, but meteors may be seen up to a week before or after.

The best time to view is from midnight to dawn. They generally appear to radiate, at 60 or more per hour, from a point high in the north.

The meteors appear to radiate from the constellation of Perseus - hence the name ‘Perseids’. The shower stems from the comet Swift-Tuttle, which has an orbital period around the Sun of ~133 years.

Further details from NASA

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New mailThe Perseid shower peaks on the morning of 12 August, but meteors may be seen up to a week before or after.

The best time to view is from midnight to dawn. They generally appear to radiate, at 60 or more per hour, from a point high in the north.

The meteors appear to radiate from the constellation of Perseus - hence the name ‘Perseids’. The shower stems from the comet Swift-Tuttle, which has an orbital period around the Sun of 133 years.

Further details from
The Perseid shower peaks on the morning of 12 August, but meteors may be seen up to a week before or after.

The best time to view is from midnight to dawn. They generally appear to radiate, at 60 or more per hour, from a point high in the north.

The meteors appear to radiate from the constellation of Perseus - hence the name ‘Perseids’. The shower stems from the comet Swift-Tuttle, which has an orbital period around the Sun of 133 years.

Further details from

Worldwide navigation declared for BeiDou

Sat, 1 Aug 2020 18:48:08 GMT

Chinese President, Xi Jinping, officially commissioned the system on 31 July at a ceremony at the Great Hall of the People in Beijing.

The 55th and final satellite in the BeiDou constellation, launched on 23 June into geosynchronous equatorial orbit (GEO) at ~22,000 miles (~36,000 km), had completed all tests and been declared operational.

Hence the 3rd-generation BeiDou system (BDS-3), which began providing navigation services in 2018, has become operational worldwide. The final constellation comprises 27 medium earth orbit (MEO), 5 GEO and 3 inclined geosynchronous orbit (IGSO) satellites.

This should provide global navigation services similar to GPS, GLONASS and Galileo. It will use, amongst other transmissions, a frequency of 1575.42 MHz - the same as GPS L1 and Galileo E1 civil signals - and multiplexed binary offset carrier (MBOC) modulation, similar to the future GPS L1C and Galileo’s E1. Satellite-based augmentation (SBAS) and SAR facilities are included.

Further details from Associated Press News

Successful GPS launch

Wed, 1 Jul 2020 10:28:53 GMT

SpaceX has launched the third GPS III satellite from Cape Canaveral.

The Falcon 9 rocket lifted off at 1610 local (2010 UTC) on 30 June from Cape Canaveral Launch Complex 40, as temperatures exceeded 30ºC. It was the first GPS launch undertaken by SpaceX.

The US Space Force had delayed the launch of GPS III SV03 from April due to the coronavirus pandemic, and it was delayed for a further 15 minutes on the day due to strong high-altitude winds.

At ~90 minutes after liftoff, SV03 was placed in a transfer orbit ranging from 250 to 12,550 miles (400-20,200 km), inclined at 55º. It will use its own propulsion to circularise the orbit at the higher altitude. It is scheduled to become operational in August, occupying Plane E, Slot 4 - replacing a remarkable satellite, launched in 2000, which had a designed lifespan of 10 years. GPS III satellites have a designed lifespan of 15 years.

SpaceX has recovered the first-stage booster from the launch rocket - the first time this has occurred on a GPS launch.

GPS III SV04 and SV05 are complete and scheduled for launch in late September 2020 and January 2021. Lockheed Martin have a further 5 satellites in test or build and are contracted to build a further 22 follow-on GPS IIIF spacecraft.

Further details from Spaceflight Now

China completes BeiDou constellation

Tue, 23 Jun 2020 09:30:04 GMT

The last 3rd-generation BDS-3 satellite required to complete full worldwide cover was launched on 23 June.

Launch took place from the Xichang Satellite Launch Centre at 0943 local time (0143 UTC), having been delayed from 16 June due to problems with the Long March-3B launch rocket.

This 55th BDS satellite will use its own propulsion to obtain a geosynchronous equatorial orbit (GEO) at ~22,000 miles (~36,000 km).

The final constellation comprises 27 medium earth orbit (MEO), 5 GEO and 3 inclined geosynchronous orbit (IGSO) satellites. This should provide global navigation services similar to GPS, GLONASS and Galileo.

The worldwide BDS-3 will use, amongst other transmissions, a frequency of 1575.42 MHz - the same as GPS L1 and Galileo E1 civil signals; and it will use multiplexed binary offset carrier (MBOC) modulation, similar to the future GPS L1C and Galileo’s E1. Satellite-based augmentation (SBAS) and SAR facilities are included.

Details from BeiDou Navigation Satellite System

Final BeiDou satellite launch delayed

Tue, 16 Jun 2020 10:01:19 GMT

Launch of the BDS-3 satellite to complete BeiDou worldwide cover was due at 0211 UTC on 16 June.

But the Long March-3B carrier rocket was found to have a technical problem during pre-launch tests, according to the China Satellite Navigation Office.

Hence the launch has been postponed, with the new launch time yet to be determined.

Details from beidou.gov.cn

GPS celebrates 25 years of operation

Wed, 29 Apr 2020 16:30:44 GMT

GPS became fully operational on 27 April 1995.

On this date in 1995, the system reached full operational capability (FOC), having passed through initial stages (IOC) since 1993.

The USAF Vice Chief of Staff declared in 1995: ‘This is a major milestone, GPS has become integral to our war-fighters and is rapidly becoming a true utility in the civilian community.’

On this 25th anniversary, the US Space Command Commander has declared: ’The United States Space Force’s continuing objective for the constellation is to ensure GPS remains the Gold Standard for global space-based positioning, navigation and timing.’

The US Space Force (USSF) reminds us that ‘The GPS operational constellation currently has 31 satellites, and the system is continually updated and modernised, making it a resilient system to maintain the signals required for accurate positioning, navigation and timing around the world.’

The Commander of the 2nd Space Operations Sqn (2SOPS), which operates GPS, concludes: ‘The 25th Anniversary is a huge, momentous occasion for us. We take great pride in providing this global utility to the approximately 6 billion users worldwide. Celebrating this anniversary gives us a moment to recognise how far we’ve come, but also to get pumped about what lies ahead for our programme and our role in executing that.’

Details from US Space Force

New GPS Performance Standard

Wed, 22 Apr 2020 11:21:17 GMT

The USAF released the 5th Edition of the GPS Standard Positioning System (SPS) Performance Standard (PS) on 16 April.

This first update to the SPS PS since 2008 now includes pre-Initial Operating Capability (IOC) performance standards for new civil GPS signals L2C and L5, in addition to L1 C/A. It specifies the levels of SPS performance in terms of broadcast signal parameters and constellation design.

USAF reminds us that, since GPS initial operational capability (IOC) was first declared in 1993, actual performance has continuously met and exceeded minimum performance levels specified in the SPS PS, and users can generally expect improved performance over the minimum levels described in the Standard. For example, with current Signal-in-Space (SIS) accuracy, well-designed GPS receivers have been achieving (95%) horizontal accuracy of 3m or better and vertical of 5m or better.

It adds that any use of the pre-operational signals L2C and L5 is at the users’ own risk until those signals are declared fully operational and incorporated as operational signals in future editions of the SPS PS.

The new Standard can be found at GPS SPS Performance Standard 5th Edition April 2020 (PDF)