Final Rokot Launches Sentinel 3B

What Sentinel 3B looks like
Artist’s view of what Sentinel 3B looks like when up in space, sadly there are not many images of it for real! Credit: ESA/ATG Medialab

On April 25th, 2018, at 17:57 UTC a Russian Rokot/Briz KM rocket launched from Site 133, pad 3 from Plesetsk Cosmodrome. Aboard was Sentinel 3B, an Earth observing satellite, part of Europe’s Copernicus environmental monitoring network. This marks the final commercial Rokot Launch, and the final Eurokot mission. There are some more Rockot launches planned for the Russian government though, after which it is reportedly that the repurposed missile launch system will be retired.

Sentinel-3B UC exit from MIK go to Launch pad
The Sentinel 3B being transported to the launchpad by the russian train system.

Sentinel 3B is a Thales Alenia Space Prima Bus satellite, designed to measure ocean temperatures, colour, surface height and the thickness of sea ice. While it is over land it can measure the height of rivers and lakes, monitor wildfires, provide maps of land use and monitor vegetation. The satellite has been designed for many uses. Created for the European Space Agency, the satellite will join Sentinel 3A in orbit to symmetrically monitor the Earth. The data will be primarily fed into the Copernicus Environmental Monitoring Service, where the applications can be developed from to use the data.

Sentinel 3B in integration
An image of the Sentinel 3B satellite just before it was sent off to Russia to be put on the Rokot. Credit ESA

The satellite carries many payloads to track the huge amount of data it is recording, these include:

  • OLCI (Ocean and Land Colour Instrument)
  • SLSTR (Sea and Land Surface Temperature Radiometer)
  • SRAL (Synthetic Aperture Radar Altimeter)
  • MWR (Microwave Radiometer)
  • LRR (Laser Retroreflector)
  • GNSS (Global Navigation Satellite System)

Thales Alenia Space was the prime contractor, responsible for constructing the spacecraft and the SRAL instrument, as well as contributing to the supply of the SLSTR instrument. Many European companies were involved in supplying the SLSTR instrument, including SELEX Galileo, RAL (Rutherford Appleton Laboratory), Jena-Optronik, Thales Alenia Space, ABSL and ESA-ESTEC. EADS CASA Espacio was contracted to provide the MWR instrument. CNES was contracted to provide the DORIS instrument.

Mediterranean Sea
An image of the Mediterranean Sea taken by Sentinel 3A, the partner of Sentinel 3B, they will don the same job on opposite sides of the Earth. Credit: ESA

When Planes Need an Eye Test: NOLF Webster.

webster overall map
From Google Maps. the locations and distances between the 4 photo resolution markers. Taken in 2007.

In a previous post, I put together lots of images of photo resolution markers, from across the USA. This post is about the four markers found at a little known airfield named Naval Outlying Field Webster in Maryland. In posts on this subject in other blogs it is often incorrectly named Walker Field, just to make things confusing. The four markers are in a straight line, with an almost exact 2000ft between them. This is likely for some sort of calibration testing, so the planes have an exact known distance to calibrate their cameras from. They are in parallel with one of the main runways to make it easy to maintain them, and as another reference for the planes.

Photo res marker 1
The most eastern photo resolution marker at Naval Outlying Field Webster. Taken in 2007 by Google Maps.

NOLF Webster is located 12 miles south west of Naval Air Station PAX River. It was bought by the military from a set of jesuit fathers during WW2 for just $96,000. It was bought as a auxiliary airfield for PAX River, to send aircraft to on busy days. PAX River is a very famous aircraft testing base, with lots of history associated with it. Part of the history is the photoreconnaissance training school found there. That explains the reasoning for the photo resolution markers just 12 miles to the SW.

Photo res 2
The second photo resolution marker at Naval Outlying Field Webster. Taken in 2007 by Google Maps.

NOLF Webster is good as an air base due to it’s great location. It has a good approach by water from two sides, especially good for testing and training. The other approaches were mainly woodland and fields. The three runways are built in accordance with the prevailing winds, with two of the runways being 5,000ft long. The base was heavily used in the 1950’s as a ‘touch and go’ site for training at PAX.

photo res 3
The third photo resolution marker at Naval Outlying Field Webster. Taken in 2007 by Google Maps.

In the 1960’s the former electronics test division moved in, now known as Naval Air Navigation Electronics Project (NANEP). They helped develop many air navigation systems. They stopped the interference with operations at PAX River. They may also have been a big part on the development of the photo resolution markers found there.

photo res 4
The fourth photo resolution marker at Naval Outlying Field Webster. Taken in 2007 by Google Maps.

Most of the images I have used are taken in 2007, but the final one (of the fourth marker) is taken in 2015, where it has a slightly different pattern. This is maybe to define markers between each of them, so the planes know the final one. There don’t seem to be any other changes according to the images found on Google Earth.

photo res 4
The fourth photo resolution marker at Naval Outlying Field Webster. Taken in 2015 by Google Maps.

Hope you enjoyed this short post, If you enjoy stories and posts on space and electronics, take a look at some of the other posts on my blog. Thank You for reading.

The Foundry: Put a Lid On It

In the previous foundry post, we made the foundry hugely more efficient by adding a fan to force air into it using an old hairdryer. Although it made the fire super hot it introduced many problems. It forced the tiny pieces of ash sitting in the foundry into the air, and towards anyone in a 2m radius. Some of the fuel also gets forced out which makes it less efficient. Bad all round, especially for the neighbors clothes on the washing line, which probably smelt smoky after each burn. We came to the conclusion that we needed a lid to hold in that glorious heat.

The fire burning
The fire burning with a steel tin on top to stop the ash flying out.

We went to the internet and found the easiest way to make the lid is to just make it in the same way we made the foundry itself, but with a few modifications. Firstly we made much less, we only want a lid about an inch thick (2.5cm) for a lid. This size was thick enough to be strong, but not so thick that it was unusable. We also used a plastic bucket rather than a metal one. As plastic can be bent it allows some movement to get the set lid out of the bucket without breaking either. You also need something to make the hold in the centre, we used a bottle, but if you can find something with a nice base then use that, the bottle had its drawbacks. Make sure the item you use can be ruined, and has a slight taper, because it needs to come out when the lid is set. Once put together we left the lid for a day to set, just like with the foundry.

The new lid
The new lid sitting inside the bucket setting, with the bottle in the centre to make the hole.

As you can notice in the above image we added a way to pick up the lid. This is firstly really useful to take out of the bucket, but will also be useful when we are actually using the forge and things get hot. It is much easier if we have something to actually grab on to. We used standard off the shelf D rings from ScrewFix, but anything that has a good ring and plenty of metal for the mixture to mould around then it should work fine. For us, it made the act of picking up the lid much easier.

the first lift test
The first attempt to lift the lift after it had been taken out of the bucket.

So once it was out, we left the lid out of the mould overnight, and then tried it out the next day. For the first burn with it we were gentle, and barely put on the hairdryer. This was to make sure that we didn’t damage it, we really wanted to help the curing process. You can see the difference in the below picture though, all the heat is confined inside the forge, and no ash or particulate is coming out the top. To add or remove the lid from the top we used kitchen tongs, as the D rings get very hot. We also hd head gloves to make sure we didn’t burn ourselves in the process. Safety is paramount if doing this yourself. It is easy to make a new lid but it isn’t easy to fix third degree burns! you have been warned. That being said, from our perspective that is a working forge! Now onto melting things.

The lid setup
The full setup, with the lid on it , the first burn was much gentler to allow the lid to set better, we though an extrer first burn could damage it.

Hope you enjoyed this post, hopefully there will be another update soon, but for now search the rest of the blog, as there are some awesome images of rockets, interesting history about aerospace, and you might learn something about electronics. Thanks for reading.

The Exoplanet Hunter TESS Launched by Falcon 9

TESS taking off
The Falcon 9 taking off from SLC-40 at Cape Canaveral with TESS on board. Credit: SpaceX Flickr.

On April 18th, 2018 at 22:51 UTC a Falcon 9 took off from Launch Complex 40 at Cape Canaveral AFB. Aboard was NASA’s latest research satellite TESS. A mission that cost $337 million, Transiting Exoplanet Survey Satellite (TESS)  is the latest in a line of space based observatories that are set to launch this decade. Launched into an arching elliptical orbit that will take the spacecraft over two thirds of the distance to the moon. The first stage of the Falcon 9 landed on the autonomous drone ship Of Course I Still Love You to be refurbished and reused.

falcon 9 engines
The sheer power of the Falcon 9’s nine Merlin 1D engines produce an awesome inferno. You can clearly see the 45 written on the side as the booster designator. Credit @marcuscotephoto on Twitter.

After a 5 day checkout of the spacecraft, basically a hardware check, the ground controllers will switch on the TESS cameras. TESS is designed to scan around 85% of the sky during the two year mission, with astronomers estimating as many as 20,000 new planets could be found. It plans to build on discoveries made by NASA’s Kepler telescope which was launched in 2009 to find earth like planets. TESS carries four 16.8-megapixel cameras, and will look for dips in light coming from 200,000 preselected nearby stars. The four cameras cover a square in the sky that measures 24 x 24 degrees, wide enough to fit the Orion constellation into a single camera. the cameras together study a set area of sky for 27 days before staring at the next section.

TESS orbit
An illustration of the orbits that TESS will go through to get to the final orbit P/2. Credit: NASA.

The orbit TESS is being launched into is known as P/2, and requires time and finesse to reach. TESS will slingshot by the moon at a distance of around 5,000 miles (8,000 kilometers), using gravity to reshape its orbit, increasing the satellite’s orbital perigee, or low point, to the final planned altitude of around 67,000 miles. After the lunar flyby, the high point of the satellite’s elongated orbit will stretch well beyond the moon, and another thruster firing will nudge TESS into its final orbit in mid-June. Science data is planned to start in july, with the first year of the two year campaign aimed at the stars in the southern sky. TESS has been built to have enough fuel to last 20 or 30 years, assuming funding by NASA and the components on board continue to function correctly.

the TESS telescope
The TESS satellite before launch, the four cameras can be seen on the top of the spacecraft; Credit: NASA.

Each of TESS’s cameras have four custom built re-sensitive CCD sensors designed and developed by MIT’s Lincoln Laboratory. The sensors are claimed to be the most perfect CCD’s ever flown by a science mission. The lenses used by the cameras are only about 4 inches (10mm) wide, meaning it has a fairly low light collecting power compared to other space telescopes. The James Webb Space Telescope for example launching in 2020 had a 21.3ft (6.5m) primary mirror, although the satellite has cost over $8 billion to make. TESS is a bit like a finder telescope, it will lay a bedrock for future missions such as Webb and ground based observatories to make better readings. It gives a good idea of the best places to look, where the most likely exoplanets are.

launch of TESS
The Falcon 9 launching the Transiting Exoplanet Survey Satellite to an orbit of P/2. Credit: SpaceX Flickr.

TESS works by looking at a star, in this case mainly M-dwarf stars, which are cooler than our sun. They are also known as red dwarfs and make up most of the stars in our galaxy. When a planet goes in front of the star the light received by TESS “dips” and changes slightly in colour. This change in the light it receives can tell scientists alot about the size of a planet, and other things like density and velocity. They expect TESS to find between 500 and 1,000 planets that are between one and three times the size of Earth, and 20,000 planets the size of Neptune or Jupiter. The readings will give a good idea of where to focus on and ‘follow up’ on future missions. Then missions such as JWST can probe and use more complex tools to find information such as atmospheric composition, and whether they could be habitable.

long exposure TESS
A long exposure of the Falcon 9 taking off over the SpaceX hangar at Cape Canaveral. Credit: SpaceX Flickr.

The Falcon 9 used was a v1.2 with designation F9-54. It used a brand new “Block 4” first stage. The booster designated B1045 has a clear 45 written on the side in some of the close up booster images. The fist stage boosted for 2 minutes and 29 seconds, then detaching and slowing itself down. The booster landed downrange on the autonomous drone ship “Of Course I Still Love You”. The first successful drone ship landing since October 2017. A total of 24 Falcon 9 or Falcon Heavy booster stages have now been recovered in 30 attempts. Four of which were on “Just Read The Instructions” off the coast of California, ten at Cape Canaveral Landing Zone 1 and 2, and nine on the autonomous drone ship “Of Course I Still Love You” off the Florida Coast. 18 first stages have been recovered, 11 of which have flown twice, five have been lost during their second flight. B1045 was the last brand new “Block 4” Falcon 9 booster.

TESS taking off
An awesome photo of a Falcon 9 taking off from across the water, a perfect day for pictures! Credit: SpaceX Flickr.

To find similar photos, and to buy reasonably priced prints of some of the above visit

Atlas 5 Launches a Trio of Spy Satellites

Atlas 5 taking off
Atlas 5 lifting off from pad 41 at Cape Canaveral Air Force Base. Credit: @marcuscotephoto on Twitter

At 23.13 UTC on April 14th 2018 the third Atlas 5 launch of the year fired multiple military satellites into a near geosynchronous orbit. Launching from Space Launch Complex 41 at Cape Canaveral, FL,  the AV-079 (the launch designation) was an Atlas V in 551 configuration. The rocket had 5 solid rocket motors, a Centaur second stage powered by a single RL10C-1 LOX/LH2 engine, and a 5m diameter payload fairing. The entire mission lasted approximately 7 hours and is known as Air Force Space Command (AFSPC) 11 mission.

The Atlas 5 AFSPC11
The Atlas V carrying AFSPC11 for the Air Force Space Command. Credit: United Launch Alliance Flickr.
the smoke trail
A smoke trail left by the Atlas V as it launches a trio of spy satellites. Credit: @marcuscotephoto on twitter.

The mission lifted two primary satellites for the Air Force, one stacked on top of the other. On the top was CBAS (Continuous Broadcast Augmenting SATCOM) an abbreviation within an abbreviation, and a military communications satellite. The second satellite was named EAGLE (ESPA Augmented GEO Laboratory Experiment) which is an abbreviation with two abbreviations in it! This satellite is based on an Orbital ATK ESPA bus, it is a research laboratory that can host 6 deployable payloads. It is said that EAGLE likely weighed around 780 kg. There was also a subsatellite named “Mycroft” reported to be on the flight, but not confirmed.

The fury of the Atlas V
The fury of the 5 solid rocket boosters found on this Atlas V. Credit: United Launch Alliance Flickr.

The Solid motors finished their burn and seperated 1 minute and 47 seconds after liftoff. The first stage,  an RD-180 rocket fired for 4 minutes and 33.5 seconds. Centaur then performed 3 burns which were not shown on the livestream. The first burn was meant to last 6 minutes 1 seconds to reach a low earth parking orbit. The second burn began 12 minutes and 6 seconds after the first cutoff, and last 4 minutes and 49 seconds, putting the vehicle into a geosynchronous transfer orbit. After a 5 hour and 6 minute apogee, a third burn of 2 minutes and 36 seconds completed the insertion to the planned orbit. A spacecraft separation extended for another 1 and a half hours to T+6 hours 57 min 24 sec.

Atlas v launchpad
Atlas V rolling to the launchpad at Space Launch Complex 41 at Cape Canaveral AFB. Credit: United Launch Alliance Flickr.

To find similar photos, and to buy reasonably priced prints of some of the above visit

The NOR Gate That Got Us To The Moon

Type G micrologic
The Fairchild Type ‘G’ Micrologic gate for the Apollo Guidance Computer – this is the flat pack verison

In a previous post I talked about how the going to the moon kick started the silicon age. If you haven’t read it, it is short but really interesting story about how NASA made Integrated circuits cheap, and partially funded what we now know as Silicon Valley. In this post I am going to take a slightly closer look at the circuit that ran the famous type “G” Micrologic gate that ran the Apollo Guidance Computer.

apollo 3 input NOR gate
The official NASA schematic of the Type G micrologic gate found in the Apollo Guidance Computer

As you can see in the above image, the circuit was not particularly complicated. You have to remember that this is very early logic, before CMOS or NMOS or any other fancy IC technologies. This is basically two 3 input NOR gates, they both run off the same power, with pin 10 at the top, and the negative which was likely ground being shared on pin 5. The output for the left NOR gate is pin 1, and the output for the right is pin 9. The three inputs for the left are pins 4, 2 and 3, with the right having pins 6, 7, and 8 as inputs. Simply put, the output is “pulled” high to power when all the inputs are OFF. The resistor between pin 10 and pin 1 (or 10 and 9) are a simple pull up resistor as you would find in most electronic circuits. As expected with a NOR gate, the output will be only be ON when all the inputs are OFF. When any of the inputs are ON the output of that gate will be pulled to ground. One two, or all the inputs can be on, but it just needs one to turn OFF the output. The resistors going into the base of the transistor are just to limit the current.

3 input NOR
My breadboarded version of the 3 input NOR gate, it is made with BC547 transistors and a DIP switch. the output has been inverted with the LED.

I made a simple recreation of this circuit using BC547 NPN transistors, but most NPN transistors would work, these were ones I found in my parts box. As you can see in the image above, I have made it on a breadboard, with the inputs being a DIP switch attached to the power (5V in this case). The base resistors for the transistors are 1K and the pull-up to 5V is a 10K. I recommend making up this circuit if you want to learn a bit more about logic, and is a cheaper method than going out to buy 74 series logic chips! As you can see in the images there are a number of states that I showed the circuit in, and notice that if any of the switches are on, the circuit turns on, this is slightly against what I mentioned earlier, but thats due to the output LED using the transistor as a current sink, not a source, so the output is inverted. Basically, when the output is 0 the LED turns on. The only time the LED is off (output high) is when no switches are on, meaning all the transistors are off.

apollo 3 input NOR gate
An image of the silicon die inside the Type G 3 input NOR gate. We will be going through how the layout works in a future post.

The final point for this post is why the circuit is actually quite inefficient. Modern logic is amazingly low power compared to this. One of the biggest issues is that it is always taking power in some way. When the inputs are off, there is still some leakage through the pull up resistor, when an input is on, then there is current going through the resistor to ground. Also, by the nature of the transistors there is always parasitic leakages, and inefficiencies in the process. They are only small numbers, but the AGC used over 3000 of these circuits, so the small leakages soon add up to draw some hefty power needs, especially for battery powered operations.

If you enjoyed this post, take a look at the rest of my blog, there is lots about space, electronics and random history. I am always open to ideas and feedback, and where is best to post links to my posts.

VA242: Ariane 5 Launch

VA242 launching
VA242 launching with two satellites aboard weighing almost 10 tonnes. Credit: Arianespace Twitter.

At 21:34 UTC on the 5th of april 2018, an Ariane 5 with ECA vehicle number L5102 launched two communications satellites into orbit. The successful flight launched from Kourou in French Guiana from Pad ELA-3. The mission named VA242 placed Japan’s DSN 1/Superbird 8 and Britain’s Hylas 4 into their planned orbit. VA242 was the 64th Ariane 5 ECA success in 66 flights. Both satellites were placed in a 250 x 35,786 km x 3 deg geosynchronous transfer orbits about 34 minutes after takeoff.

Ariane 5 liftoff
Ariane V L5102 lifts off from Kourou in French Guiana on April 5th. Credit: Arianespace twitter.

The Japanese DSN 1/Superbird 8 is designed to provide X-band communications for the Japanese Ministry of Defence. It will also provide Ku and Ka band commercial services for Sky Perfect JSAT Group from 162 degrees East. The satellite is a NEC Corporation DS2000 series, weighing 5,348kg.

Ariane V launch
VA242 lifts off from pad ELA-3 at 21:34 UTC placing a Japanese and British satellite into Geosynchronous Transfer Orbit. Credit: ArianeSpace Twitter.

The British Hylas 4 was built for British-based Avanti Communications, is designed to provide Ka band communication services to Europe and Africa from 33.5 degrees West. Designed by Orbital ATK it is a GEOStar 3 series weighing 4,050 kg.

Birds flying
Birds flying away as VA242 launches from French Guiana. Credit: Arianespace twitter.

VSS Unity: Virgin Galactic Is Back

VSS unity Flight
VSS Unity during its first test flight. Credit: Virgin Galactic.

On Thursday 5th of April 2018, Virgin Galactic’s SpaceShipTwo conducted its first powered test flight of 2018. With very little in the media from Virgin Galactic recently, this has been a welcome development in the field of space tourism, and the development of space planes. Named the VSS Unity, this space plane is the newest development from the Spaceship Company.

USS Unity engine
USS Unity with an ignited engine rapidly accelerating into the sky. Credit: Virgin Galactic.

Virgin Galactic hasn’t performed a powered test flight since 31st of October 2014 when the VSS Enterprise experienced a catastrophic mid flight failure. The incident in the first of 5 planned SpaceShipTwo aircraft ended with a tragic accident which resulted in the death of one test pilot and serious injury to the other. With the program many years behind schedule, many critics thought this could have been the end for Virgin Galactic. Fortunately, Virgin Galactic have said the fault was not in the hardware, and was a change in safety procedure rather than a design overhaul. Over the last year, Virgin Galactic has made significant progress, leading to this powered test flight.

VSS Unity Gliding
VSS Unity, gliding back to earth after it has burnt all of the fuel, it can see the curvature of the earth. Credit: Virgin Galactic.

An NTSB investigation into the accident concluded that a pilot prematurely deployed the feathering system on the spacecraft. The system is used to increase drag during reentry. Many have criticised Scaled Composites (the manufacturer) and Virgin Galactic for not having fail-safe’s in place to prevent this problem. This is what lead into the review into the safety of the craft. After the loss of the USS Enterprise, and the safety reviews, the USS Unity was not ready until february 2016. This was the first plane to be built in house by The Spaceship Company.

WhiteKnightTwo carrying VSS Unity during the flight test, it will drop the craft at 50,000 ft. Credit: Virgin Galactic.

Up until this point the testing has been more gradual than planned, with captive carry tests, and a total of 6 successful glide tests. There was a dry run rocket test on 4th of August 2017, where water was mounted in place of rocket fuel to simulate the shift in gliding with various centres of gravity, as well as the change of weight as the rocket uses up the fuel. These tests ended positively, with the Chief pilot David Mackay stating “We are really pleased with what we saw today. We collected hundreds of gigabytes of data for us to review, and from the pilots’ point of view, it felt really wonderful.”

Pilots walking
The pilots walking toward the VSS Unity to conduct the first powered test flight. Credit: Virgin Galactic.

The FAA approved a revision to Virgin Galactic’s Commercial Space Transportation Licence in 2017. This allowed Virgin Galactic to launch out of Spaceport America in New Mexico as well as Mojave Air and Space Port in California. Virgin also announced that the Kingdom of Saudi Arabia would invest $1 billion across the Spaceship Company, Virgin Galactic and Virgin Orbit.Currently under review, if approved the deal would help finance SpaceShipTwo during 2018.

WhiteKnightTwo taking off
WhiteKnightTwo taking off to conduct the first powered test light of VSS Unity being held underneath it. Credit: Virgin Galactic.

VSS Unity is powered by a hybrid rocket engine called RocketMotorTwo. The engine originally used rubber based hydroxyl-terminated polybutadiene (HTPB) as the fuel, and nitrous oxide as the oxidiser. In 2014 Virgin Galactic switched to a plastic based thermoplastic polyamide for the fuel to improve performance. Although tested, and not the cause of the crash of VSS Enterprise, Virgin Galactic opted to use HTPB after extensive testing at Mojave.

spaceport America
VSS Unity attached to WhiteKnightTwo flying over Spaceport America. Credit: Virgin Galactic.

The test used WhiteKnightTwo to lift the VSS Unity to an height of 50,000 feet, then release it. Once clear, VSS Unity ignites and ascends rapidly. The burns during the real flights will last just over a minute, but this test used a much shorter burn. This is the incremental approach that Virgin Galactic have opted for. Unlike a normal rocket, the engine thrust will decrease over time, so that the G-forces stay reasonably comfortable, as this is meant to be a pleasure ride. Once the engine cuts off, the craft coasts to the apogee and glides back to the spaceport. The tests can only get the craft to 80 km, which is not officially recognised as space, due to the extra test equipment needed. Virgin Galactic claim to be confident that the craft will reach space in the final version.

What We Learnt From The Peter Beck AMA

Peter Beck is the CEO and founder of Rocket Lab, a US/New Zealand orbital launch provider who is trying to provide access to space for small satellites. On at 19:00 UTC on April 5th he participated in a Reddit AMA on /r/space, where he answered as many questions as he could about the Electron launch vehicle and the upcoming ‘it’s business time’ launch, as well as what the future of space access looks like. It was a good AMA, he answered lots of questions, and the full post can be found here. This post is to round up some of the most common and important questions he got asked for those interested.

Peter Beck by Electron
Peter Beck, president of Rocket Lab in front of the Electron launcher. Credit: Rocket Lab

The most questions came with reference to SpaceX, and the way their business model compares to Rocket Lab.

SpaceX didn’t see a market It’s known that the Falcon 1 was a similar size to the Electron and they quickly moved on from it. So people asked if SpaceX didn’t stay with it, why will it work for Rocket Lab?  Peter makes the point that SpaceX retired that rocket 10 years ago, and most of Rocket Labs customers didn’t even exist then. He mentioned that Electrons manifest is fully booked for the next 2 years for dedicated flights. He also doesn’t see a slowdown in demand anytime soon.

Reusability – On the SpaceX front, they have made big inroads to reusability and the Electron is not reusable, so many asked about plans to make a reusable version. The simple answer he gave was that reusability makes sense for medium lift vehicles like the falcon 9, but it doesn’t scale well to small vehicles. So it isn’t on the radar for them at the moment.

Electron Launch Vehicle
Rocket Lab’s first Electron rocket, seen here in a hangar at the company’s New Zealand launch site. Credit: Rocket Lab

Other Rocket Manufacturers – As there are many small rocket manufacturers popping up, and attempting to compete in this space, many wanted to know what the market is actually like for them. His comment was that not all of those manufacturers will make it, and they are currently the only dedicated small launcher that has actually made it to orbit. Others were quick to point out that other rockets of similar size do launch but nowhere near as frequently and do not have the same quality or launch frequency as the Electron.

Where else will they launch from – Currently they have a single launch site, but many wanted to know if they will branch out, to different pads of even different countries, maybe even pad-39A. He mentions that he wants to have many potential launch pads to serve many different inclinations, but Launch Complex 1 is a good start.

Going Bigger – There were lots of questions about making a bigger rocket, like an Electron Heavy. He made a point of saying they are currently only making one product really well. They have no plans to make bigger rockets, and they understand the market they are in. Rocket lab do not want to compete with SpaceX on these launches. He mentions that they can launch a huge amount of spacecraft to LEO, and going bigger only allows a 2% increase in market at the moment. That being said they will continue improving the rocket as they go along.

electron on the pad
The Electron launch vehicle waiting on the pad for takeoff, Credit: Rocket Lab

Using composites – As the LOX tank and other parts are made of carbon composites, there were questions about the difficulty surrounding the design and development of that. He talked about the several years developing and testing the composite tanks. The two main issues being microcracking and oxygen compatibility. They ended up with liner-less tanks with common bulkheads that have similar oxygen compatibility to aluminium but much lighter mass. All the composite manufacturing is in house. Some wanted to know how they manage to use such expensive processes, and he says that although carbon fibre is expensive, when done right you can use very little of it.

Why black – with most rockets out there being white, to help with the thermal efficiency, why did they go for black? Well the simple answer he gave was it looks better. Many engineers wanted to paint it, but the thermal experts made a special effort to make sure they could keep it black. Also, it does save some time/money/weight on paint.

It’s all about the money – The key question is, is it profitable, and when will they start making those profits? Well Peter states that they will see positive cash flow after their 5th flight. Each launch costs $4.9 million to each customer, and they get a dedicated launch, so no need to worry about rideshares where they have less control.

Electron Launch
Electron Rocket takes off from Rocket Lab Launch Complex 1 during the “Still Testing” mission. Credit: Rocket Lab

Adding to space junk – In the news recently, there has been lots of the junk that currently floats in space, so there were some questions on how the Electron tries to stop being just more rubbish. Peter talks about the Curie stage of the rocket that is designed to fix this issue. It puts it the second stage into an orbit that makes it deorbit quickly, and the kick stage can deorbit itself. Also most of the LEO payloads they will orbit will deorbit within 5-7 years.

Launch cadence – A few asked how often they are able to launch rockets, or at least the plans to do so. He mentioned that the current plan is to launch once a month for the next year, then once every two weeks, and then double down from there. The Launch complex 1 can support a launch every 72 hours, which is pretty impressive.

Job opportunities – As you would expect, many people asked how you get a job/internship at Rocket Lab. Peter gave a link to email a resume to, but mentioned that the bar is high, they are open to new people but they have to be passionate, and enjoy (and be good at) what they do. They are a small team trying to do big things! They care about what you do outside your formal education, what are you passionate about? what have you built, tested and broken?

Rocket testing
Rocket Lab testing its engines for the Electron launch vehicle. Credit: Rocket Lab

Some hardcore technical answers

  • Each propellant had a dedicated and independent pump system rather than a single electric motor.  That was due to wanting super accurate control over the oxygen fuel ratio and startup and shutdown transients.
  • Ignition is from an augmented spark igniter (a spark plug surrounded by a tube, what acts sort of like a blowtorch).
  • The engine is fully regeneratively cooled, 3D printed chamber.
  • The area ratios for the booster and vacuum nozzles are 14 and 100 respectively.
  • The steering and ullage on the upper stage is controlled by cold gas RCS and PMD.
  • The whole vehicle is non pyro, the decouplers are all pneumatic.

A New Years Trip to Stourhead

Although we are a few months into the year I thought I would make a short post about a trip we took just a couple of days into the new year of 2018. With the family and my girlfriend, we set out on a chilly day, with snow still in some shadowy areas, we visited the nearby Stourhead. A very picturesque place, and a nice place to spend an afternoon. Also, there is plenty of history surrounding the place to get stuck into. I took a few photos on my phone, and I thought I would share.

The Stourhead Sign
The national trust sign in the Stourhead cafe.

Stourhead is a 2,650-acre estate around the source of the river Stour. It is near Mere in Wiltshire, and contains the village Stourton, extensive gardens, farmland, woodland and a palladian mansion. The estate was owned by the Stourton family for 500 years, until they sold it to Sir Thomas Meres in 1714. The Stourton family has a Peerage associated with it, so there is a  Baron Stourton. In 1717 It was sold to Henry Hoare, the son of a wealthy banker, and he demolished the original manor house. Colen Campbell and Nathaniel Ireson designed and built the current house between 1721 and 1725. Over the next 200 years the family collected lots of heirlooms, including a large library and art collection. In 1902 there was a bad fire in the house, but most of the heirlooms were saved. The house was rebuilt almost exactly the same. The son of the final owner, Sir Henry Hugh Arthur Hoare, gave the house and gardens to the National Trust in 1946, a year before he died. His son died at the Battle of Mughar Ridge during World War 1.

The Stourhead Lake
The stourhead lake taken from next to the grotto.

Most people got to Stourhead the walk around the lake and gardens. Taking a walk around the lake is meant to evoke a journey based on Aeneas’s descent into the underworld. The buildings and monuments around the lake are in remembrance of family and local history. The style of the garden is meant to be inspired by a painting bought by Henry Hoare, Claude Lorrain’s Aeneas at Delo. The gardens were designed by Henry Hoare II  and laid out between 1741 and 1780. The lake was artificially created by damming the small stream. The concept of the small areas with a big monuments is that they invite you over, and then you can see the next one, and that invites you over to that, it is designed to make you want to walk round the garden.

The view from the grotto
The awesome view of the lake from inside the grotto.

Stourhead, as its name suggests is where the river Stour starts. It is a 61 mile (98km) river which flows through Wiltshire and Dorset, and drains into the English channel. It is sometimes known as the Dorset Stour to distinguish it from the rivers of the same name in Kent, Suffolk and the Midlands. According to Brewer’s Dictionary of Britain & Ireland, the name Stour rhymes with hour and derives from Old English meaning violentfierce or the fierce one. A large part of the river is followed by the now disused Somerset and Dorset Joint Railway. These trailways are now parts of the Stour Valley Way, a trail that follows the river from the mouth all the way to stourhead, running roughly 64 miles. A number of towns and villages in Dorset are named after the river, including East Stour, West Stour, Stourpaine, Stourton Caundle, Stour Row, Stour Provost, Sturminster Newton, and Sturminster Marshall. Sturminster Newton is famous for a water mill and town bridge which still has a notice warning vandals of penal transportation for those who wish to damage the bridge.

just a soppy photo
A soppy selfie of me and Katie walking up the big hill to the Temple of Apollo.

There are some great little facts that come from Stourhead,might be useful for a pub quiz, or just to annoy your friends.

  • The Temple of Apollo and Palladian Bridge can be seen in the 2005 film Pride & Prejudice, the one starring Keira Knightley.
  • In the Thunderbird TV series (the original one with the puppets), the model for Lady Penelope Creighton-Ward’s mansion was based off of Stourhead house.
  • The corporate font for the National Trust font is based on an inscription in the grotto. It was created in 1748 but was accidentally destroyed by mistake in the 1960’s, so the one there now is a replica.
  • King Alfred’s tower, a folly on the Stourhead estate, was built near Egbert’s stone, where it was said that Alfred the Great, King of Wessex rallied the Saxons in May 878 before the Battle of Edington.
  • King Alfred’s tower is the start of a 28 mile footpath called the Leland Trail that runs to Ham Hill country park.
The View From Apollo
The view of the lake from the Temple of Apollo

link to information about the Stour Valley Way (Long Distance Walkers Association):