
Some sections of the tabloid media became excited this week about “cracks” being discovered “on the International Space Station”, with one or two predicting the end of the ISS is now nigh.
The cause of the reports was the announcement by Energia NPO, the company responsible for fabricating the Russian-built elements of the ISS, that “superficial fissures” have been found in the outer skin of the Zarya module.

Zarya – also called the Functional Cargo Block (FCB) – was the first module of the ISS to be launched (November 1998), and was initially responsible for providing electrical power, storage, propulsion, and guidance to the ISS during the early years of assembly. However, as more specialised units, notably the Russian Zvezda module (attached to the aft end of Zarya), were launched, the role of the Zarya module has been gradually downgraded to the point where today it is primarily used for internal and external storage space.
Thus far, neither NASA nor Roscosmos have indicated whether or not the fissures have caused any internal pressurisation issues for the station. However, similar fissures – likely the result of exposure to extremes of temperature as the ISS passes between direct sunlight and the cold shadow of Earth and back every 45 minutes – were discovered on the Zvezda Module in 2019, and despite repairs in 2020 and 2021, they continue to be an annoyance.
Whether the Zarya fissures will become a similar issue can only be determined in time – but they are a reminder that while the ISS is not in imminent risk of a major failure, it is genuinely showing its age, particularly the three original modules – Zvezda, Zarya and Unity – all of which are at least 25 years old (including fabrication / construction time), and are potentially becoming increasingly vulnerable to fatigue. Such issues might also cause Russia to make further noises about withdrawing from the ISS after 2024, this time of the grounds of the station’s increasing age, so they can start work on their own space station.
The Accident – the Strangest Brown Dwarf
Brown Dwarfs are sometimes called “failed stars”, in that they have a mass that sits above the most massive gas giant planets we have so far discovered, but below that of the smallest stars. This leaves them incapable of achieving hydrogen fusion, hence the idea they have “failed” as stars. However, they are massive enough to give off considerable infra-red radiation, which tends to point to them being extremely old.
In reviewing data returned by the Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE), citizen scientist Dan Caselden has discovered the strangest brown dwarf to so far be discovered – so strange it has been given the nickname “The Accident”.
Located around 50 light years from Earth, it is officially called WISEA J153429.75-104303.3 and classified a Class Y substellar object – the oldest and coolest classification of such brown dwarfs. All of which is really not that interesting; astronomers have discovered many brown dwarfs in local space around our solar system over the last 30 years.

What is strange about The Accident is firstly, it is spinning about its axis at a speed of 200 kilometres a second (that’s 720,000 km/h)- 25% faster than the next fastest stellar object of its kind.
The second – and more intriguing – thing is that The Accident has the oddest brightness pattern of any brown dwarf. Due to their nature, these objects only give off light in the infra-red wavelengths, and The Accident’s output is – at least in part – at the end of that part of the spectrum that points to it being really old: perhaps 13 billion years old – almost as old as the galaxy itself (13.6 billion years. This extreme age is also supported by The Accident’s rotational speed, something that could only be achieved via thousands of encounters with massive stellar objects down the aeons.
But there’s a twist: The Accident is not consistent in its infra-red brightness, as it also “shines” in parts of the infra-red that indicate that it is a lot, lot, younger than the other data suggest, making the object an anomaly – and accident of nature, so to speak, hence its nickname. This difference in brightness has puzzled scientists, and has led to The Accident starting to get a lot of attention to determine what might be going on inside it.
Some of this attention is also devoted to studying it on the basis of its age – if it really is 13 billion years old, then it formed at a time when the galaxy was a very different place in terms of chemistry, a time when many elements we take for granted (carbon and methane being just two) simply could not exist. Thus, understanding its nature and composition could reveal more about the galaxy’s formation and birth. What’s more, that so strange an object should be found so relatively close to Earth suggests there could be many of these unusual brown dwarfs awaiting discovery.
Virgin Group Ups and Downs
Sir Richard Branson is having some ups and downs in his space endeavours.
The ups are with Virgin Orbit, the smallsat launching service that uses the LauncherOne rocket, lifted to altitude by a modified 747 before being launched, to place payloads of up to 300 KG to a Sun-synchronous orbit or 500 KG to low Earth orbit.
Following the first successful launch of a commercial payload to orbit at the end of June, the company has now passed a critical Federal Aviation Administration (FAA) environmental review that could allow it to use Andersen Air Force Base, on the island of Guam in the western Pacific Ocean, as a base for launch operations.

If final approval is granted – and the FAA do have reservations about Virgin Orbit being able to operate from such a remote location – the company plan to use Guam to make up to 25 air launches over a period of 5 years, possibly commencing before the end of 2021.
Following the success of the June launch, Branson noted that Virgin Orbit is to be capable of highly responsive launches from almost any point in the world. To this end, the company has already signed an agreement with Spaceport Cornwall (Newquay Airport) in the UK, and the Brazilian government has selected the company to provide launch services out of that country’s Alcântara Space Centre. These, together with Guam and their existing facilities at the Mojave Air and Space Port mean that Virgin Galactic may soon have four launch locations around the world from which it can reach a variety of orbital inclinations as required by customers.

The down is with Virgin Galactic, the sub-orbital, tourist-focused service. Following its first successful passenger-carrying flight in July (see: Space Sunday: Unity 22 Flies), the FAA announced on September 2nd that the the sub-orbital VSS Unity is grounded, following a review of that flight, forcing a halt to the company’s operations.
The review has been triggered following an article appearing in The New Yorker magazine stating the pilots on VSS Unity ignored a warning triggered during the vehicle’s powered ascent that should have caused them to abort the flight and return the the ground. The warning indicated the vehicle was not climbing at a sufficiently steep angle to remain within it’s “entry glide cone” – the volume of space in which it can make a safe unpowered glide back to a successful runway landing at the end of the flight – during its return to Earth, and so could miss the runway entirely.
While the company has defined The New Yorker’s report as “inaccurate”, telemetry from the Unity 22 mission shows that the vehicle did exceed the limits of FAA-defined “protected airspace” for one minute and 41 seconds during the descent to landing, further justifying the FAA’s decision to order the grounding, preventing any further operations by Virgin Galactic for the next few weeks.

Continue reading “Space Sunday: the ISS, SLS, brown dwarfs and other bits”























