Chris joins Matt to chat about Hycean planets, JWST and much more

And in the meantime, I'm trying to tell you we're coming in too fast. I think they know it, and I think that's why we don't have a God-damned reentry plan.

John Leonard "Jack" Swigert Jr. (August 30, 1931 – December 27, 1982) was an American NASA astronaut, test pilot, mechanical engineer, aerospace engineer, United States Air Force pilot, and politician. In April 1970, as command module pilot of Apollo 13, he became one of twenty-four astronauts who flew to the Moon.

Space News

Illness delays spacewalk

• A lengthy session of Extravehicular Activity (EVA) by Expedition 65 spacewalkers Aki Hoshide and Mark Vande Hei has been postponed, reportedly due to a crew medical issue.

• NASA on Monday announced that Tuesday’s planned U.S. EVA-77—the 77th station-based excursion conducted in U.S.-built Extravehicular Mobility Units (EMUs), without the presence of the Space Shuttle—will now occur after this weekend’s launch of the SpaceX CRS-23 Dragon cargo mission and a

• Original plans called for Hoshide (designated “EV1”, with red stripes on his suit for identification) and Vande Hei (“EV2”, clad in a pure white ensemble) to depart the Quest airlock of the International Space Station (ISS) around 8:30 a.m. EDT Tuesday for six hours and 50 minutes. Their primary task was to install a Modification Kit at the base of the P-4 truss in readiness for next year’s arrival of a third ISS Roll-Out Solar Array (iROSA).

• Additionally, Hoshide and Vande Hei—who already boast seven previous EVAs and 48 hours and 3 minutes of spacewalking time between them—would Remove & Replace (R&R) a Floating Potential Measurement Unit (FPMU) to measure the accumulation of electrical charges across the station’s solar arrays

• pair of critical Russian spacewalks early next month to commence outfitting the newly-arrived Nauka (“Science”) lab.

• But in a clipped statement on Monday, NASA revealed that U.S. EVA-77 is postponed, “due to a minor medical issue involving Vande Hei”. The agency stressed that the incident does not constitute “a medical emergency” and the spacewalk’s objectives are by no means time-critical. Indeed, responding to an AmericaSpace question at a recent pre-flight news conference ahead of Northrop Grumman Corp.’s NG-16 Cygnus cargo mission, ISS Program Manager Joel Montalbano explained that the “Mod Kit” was being installed early in order to circumvent problems down the road. The iROSA array itself is not due to be delivered until next spring, tentatively aboard SpaceX’s CRS-25 Dragon.

• As previously reported by AmericaSpace, the Boeing-led iROSA concept promises to furnish an electrical power hike of 20-30 percent for the station to support future commercial and payload requirements.

JAMES WEBB HAS FINISHED TESTING

• After successful completion of its final tests, NASA’s James Webb Space Telescope is being prepped for shipment to its launch site.

• Engineering teams have completed Webb’s long-spanning comprehensive testing regimen at Northrop Grumman’s facilities.

• Webb’s many tests and checkpoints were designed to ensure that the world’s most complex space science observatory will operate as designed once in space.

• Now that observatory testing has concluded, shipment operations have begun. This includes all the necessary steps to prepare Webb for a safe journey through the Panama Canal to its launch location in Kourou, French Guiana, on the northeastern coast of South America.

• Since no more large-scale testing is required, Webb’s clean room technicians have shifted their focus from demonstrating it can survive the harsh conditions of launch and work in orbit, to making sure it will safely arrive at the launch pad.

• Webb’s contamination control technicians, transport engineers, and logistics task forces are all expertly prepared to handle the unique task of getting Webb to the launch site. Shipping preparations will be completed in September

• “NASA's James Webb Space Telescope has reached a major turning point on its path toward launch with the completion of final observatory integration and testing,” said Gregory L. Robinson, Webb's program director at NASA Headquarters in Washington. “We have a tremendously dedicated workforce who brought us to the finish line, and we are very excited to see that Webb is ready for launch and will soon be on that science journey.”

• While shipment operations are underway, teams located in Webb’s Mission Operations Center (MOC) at the Space Telescope Science Institute (STScI) in Baltimore will continue to check and recheck the complex communications network it will use in space. Recently this network fully demonstrated that it is capable of seamlessly sending commands to the spacecraft. Live launch rehearsals are underway within the MOC with the explicit purpose of preparing for launch day and beyond. There is much to be done before launch, but with integration and testing formally concluded, NASA’s next giant leap into the cosmic unknown will soon be underway.

• Once Webb arrives in French Guiana, launch processing teams will configure the observatory for flight. This involves post-shipment checkouts to ensure the observatory hasn’t been damaged during transport, carefully loading the spacecraft’s propellant tanks with hydrazine fuel and nitrogen tetroxide oxidizer it will need to power its rocket thrusters to maintain its orbit, and detaching ‘remove before flight’ red-tag items like protective covers that keep important components safe during assembly, testing, and transport.

• Then engineering teams will mate the observatory to its launch vehicle, an Ariane 5 rocket provided by ESA (European Space Agency), before it rolls out to the launch pad. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

• The James Webb Space Telescope is an amazing feat of human ingenuity, made more impressive by the obstacles Webb personnel overcame to deliver this amazing space science observatory. Earthquakes, a devastating hurricane, snowstorms, blizzards, wildfires, and a global pandemic are only some of what the people behind Webb endured to ensure success.

• Webb’s story is one of perseverance – a mission with contributions from thousands of scientists, engineers, and other professionals from more than 14 countries and 29 states, in nine different time zones.

• 
  

• “To me, launching Webb will be a significant life event – I’ll be elated of course when this is successful, but it will also be a time of deep personal introspection. Twenty years of my life will all come down to that moment,” said Mark Voyton, Webb observatory integration and test manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We’ve come a long way and worked through so much together to prepare our observatory for flight. The telescope’s journey is only just beginning, but for those of us on the ground who built it, our time will soon come to an end, and we will have our opportunity to rest, knowing we put everything on the line to make sure our observatory works. The bonds we formed with each other along the way will last far into the future.”

• ‘Flagship’ missions like Webb are generational projects. Webb was built on both the legacy and the lessons of missions before it, such as the Hubble and Spitzer space telescopes, and it will in turn provide the foundation upon which future large astronomical space observatories may one day be developed.

• “After completing the final steps of the James Webb Space Telescope’s testing regimen, I can’t help but see the reflections of the thousands of individuals who have dedicated so much of their lives to Webb, every time I look at that beautiful gold mirror,” said Bill Ochs, Webb project manager for NASA Goddard

• Probably a december launch 2021

Few Interesting Launches coming up

Today - Friday 27th Astra Rocket 3.3 - Third Rocket 3 orbital launch attempt and first Rocket 3 commercial flight. Vehicle also known as Rocket 3.3 consists of equipment attached to the upper stage to verify the rocket's performance during launch. The Rocket 3 is a family of 11.6 m (38 ft) launch vehicles that have a payload capacity of 25–150 kg (55–331 lb) to a 500 km (310 mi) Sun-synchronous orbit. It consists of two stages. The first stage has 5 Astra engines called "Delphin"

28th Falcon 9 SpaceX CRS-23 - to ISS and a big ride share rocket, The ELaNa 37 mission will launch on this flight and also a UK satellite called Amber IOD-3

• A British company that equips spy planes and drones to track satellite telephones has raised capital to launch a handful of tiny surveillance spacecraft to listen for signals from ships operating clandestinely.

• Horizon Space Technologies, a recently established subsidiary of Berkshire, England-based Horizon Technologies, is prime contractor for the U.K. government’s cubesat signals intelligence program called IOD-3 Amber.

• Amber IOD-3, its first satellite, is part of the In-Orbit Demonstration (IOD) program run by government-backed nonprofit Satellite Applications Catapult.

• With funding from the U.K. government’s innovation agency, the Amber IOD-3 cubesat is being built by AAC Clyde Space to provide data for the country’s National Maritime Information Centre (NMIC). L3Harris Technologies is assisting with the payload’s development.

• deployment from the International Space Station shortly after arrival. Houston-based NanoRacks arranged for the cubesat’s deployment from the ISS

• The British government aims to use Horizon’s data to counter activities ranging from illegal fishing to human trafficking across its coastal waters.

• All passenger ships and most ocean-going vessels above a certain tonnage are required by law to be fitted with Automatic Identification Systems (AIS) transponders, enabling them to be tracked by coastal stations and satellites equipped with AIS receivers. However, ships can deactivate AIS transponders to avoid detection.

• Horizon’s satellites will supplement AIS data by picking up faint electronic signals from navigation radars and satellite phones, enabling the tracking of vessels even if they turn off AIS.

• Six satellites will enable worldwide coverage with latency under one hour.

• The market for radio-frequency mapping (RFM) networks has been expanding in recent years

• BRanson investing in companies like this in exchange for contracts for virgin orbit.

Septemeber 2nd

First flight of the Firefly Alpha commercial smallsat launcher. 26 rideshare payloads will be launched through Firefly's Dedicated Research and Education Accelerator Mission (DREAM) program.

Firefly Alpha (Firefly α) is a two-stage orbital expendable launch vehicle developed by the American aerospace company Firefly Aerospace to cover the commercial small satellite launch market. Alpha is intended to provide launch options for both full vehicle and ride share customers ...600kg to SSO or a tonne to LEO

Firefly's experimental orbit transfer vehicle (OTV) will also be tested on this flight

Mini Neptunes

Science story of the week

Mini Neptunes

We investigate a new class of habitable planets composed of water-rich interiors with massive oceans underlying H2-rich atmospheres, referred to here as Hycean worlds. With densities between those of rocky super-Earths and more extended mini-Neptunes, Hycean planets can be optimal candidates in the search for exoplanetary habitability and may be abundant in the exoplanet population. We investigate the bulk properties (masses, radii, and temperatures), potential for habitability, and observable biosignatures of Hycean planets. We show that Hycean planets can be significantly larger compared to previous considerations for habitable planets, with radii as large as 2.6 Earth radii (2.3 Earth radii) for a mass of 10 Earth masses (5 Earth masses). We construct the Hycean habitable zone (HZ), considering stellar hosts from late M to sun-like stars, and find it to be significantly wider than the terrestrial-like HZ. While the inner boundary of the Hycean HZ corresponds to equilibrium temperatures as high as ~500 K for late M dwarfs, the outer boundary is unrestricted to arbitrarily large orbital separations. Our investigations include tidally locked `Dark Hycean' worlds that permit habitable conditions only on their permanent nightsides and `Cold Hycean' worlds that see negligible irradiation. Finally, we investigate the observability of possible biosignatures in Hycean atmospheres. We find that a number of trace terrestrial biomarkers which may be expected to be present in Hycean atmospheres would be readily detectable using modest observing time with the James Webb Space Telescope (JWST). We identify a sizable sample of nearby potential Hycean planets that can be ideal targets for such observations in search of exoplanetary biosignatures.

A mini-Neptune (sometimes known as a gas dwarf or transitional planet) is a planet less massive than Neptune but resembles Neptune in that it has a thick hydrogen–helium atmosphere, probably with deep layers of ice, rock or liquid oceans (made of water, ammonia, a mixture of both, or heavier volatiles).[1]

A gas dwarf is a gas planet with a rocky core that has accumulated a thick envelope of hydrogen, helium, and other volatiles, having as a result a total radius between 1.7 and 3.9 Earth radii (1.7–3.9 R⊕). The term is used in a three-tier, metallicity-based classification regime for short-period exoplanets, which also includes the rocky, terrestrial-like planets with less than 1.7 R⊕ and planets greater than 3.9 R⊕, namely ice giants and gas giants.

A new class of exoplanet very different to our own, but which could support life, has been identified by astronomers, which could greatly accelerate the search for life outside our Solar System.

“Hycean planets open a whole new avenue in our search for life elsewhere”

Nikku Madhusudhan

In the search for life elsewhere, astronomers have mostly looked for planets of a similar size, mass, temperature and atmospheric composition to Earth. However, astronomers from the University of Cambridge believe there are more promising possibilities out there.

The researchers have identified a new class of habitable planets, dubbed ‘Hycean’ planets – ocean-covered planets with hydrogen-rich atmospheres – which are more numerous and observable than Earth-like planets.

The researchers say the results, reported in The Astrophysical Journal, could mean that finding biosignatures of life outside our Solar System within the next few years is a real possibility.

“Hycean planets open a whole new avenue in our search for life elsewhere,” said Dr Nikku Madhusudhan from Cambridge’s Institute of Astronomy, who led the research.

Many of the prime Hycean candidates identified by the researchers are bigger and hotter than Earth, but still have the characteristics to host large oceans that could support microbial life similar to that found in some of Earth’s most extreme aquatic environments.

These planets also allow for a far wider habitable zone, or ‘Goldilocks zone’, compared to Earth-like planets. This means that they could still support life even though they lie outside the range where a planet similar to Earth would need to be in order to be habitable.

Thousands of planets outside our Solar System have been discovered since the first exoplanet was identified nearly 30 years ago. The vast majority are planets between the sizes of Earth and Neptune and are often referred to as ‘super-Earths’ or ‘mini-Neptunes’: they can be predominantly rocky or ice giants with hydrogen-rich atmospheres, or something in between.

Most mini-Neptunes are over 1.6 times the size of Earth: smaller than Neptune but too big to have rocky interiors like Earth. Earlier studies of such planets have found that the pressure and temperature beneath their hydrogen-rich atmospheres would be too high to support life.

However, a recent study on the mini-Neptune K2-18b by Madhusudhan’s team found that in certain conditions these planets could support life. The result led to a detailed investigation into the full range of planetary and stellar properties for which these conditions are possible, which known exoplanets may satisfy those conditions, and whether their biosignatures may be observable.

The investigation led the researchers to identify a new class of planets, Hycean planets, with massive planet-wide oceans beneath hydrogen-rich atmospheres. Hycean planets can be up to 2.6 times larger than Earth and have atmospheric temperatures up to nearly 200 degrees Celsius, depending on their host stars, but their oceanic conditions could be similar to those conducive for microbial life in Earth’s oceans. Such planets also include tidally locked ‘dark’ Hycean worlds that may have habitable conditions only on their permanent night sides, and ‘cold’ Hycean worlds that receive little radiation from their stars.

Planets of this size dominate the known exoplanet population, although they have not been studied in nearly as much detail as super-Earths. Hycean worlds are likely quite common, meaning that the most promising places to look for life elsewhere in the Galaxy may have been hiding in plain sight.

However, size alone is not enough to confirm whether a planet is Hycean: other aspects such as mass, temperature and atmospheric properties are required for confirmation.

When trying to determine what the conditions are like on a planet many light years away, astronomers first need to determine whether the planet lies in the habitable zone of its star, and then look for molecular signatures to infer the planet’s atmospheric and internal structure, which govern the surface conditions, presence of oceans and potential for life.

Astronomers also look for certain biosignatures which could indicate the possibility of life. Most often, these are oxygen, ozone, methane and nitrous oxide, which are all present on Earth. There are also a number of other biomarkers, such as methyl chloride and dimethyl sulphide, that are less abundant on Earth but can be promising indicators of life on planets with hydrogen-rich atmospheres where oxygen or ozone may not be as abundant.

“Essentially, when we’ve been looking for these various molecular signatures, we have been focusing on planets similar to Earth, which is a reasonable place to start,” said Madhusudhan. “But we think Hycean planets offer a better chance of finding several trace biosignatures.”

“It's exciting that habitable conditions could exist on planets so different from Earth,” said co-author Anjali Piette, also from Cambridge.

Madhusudhan and his team found that a number of trace terrestrial biomarkers expected to be present in Hycean atmospheres would be readily detectable with spectroscopic observations in the near future. The larger sizes, higher temperatures and hydrogen-rich atmospheres of Hycean planets make their atmospheric signatures much more detectable than Earth-like planets.

The Cambridge team identified a sizeable sample of potential Hycean worlds which are prime candidates for detailed study with next-generation telescopes, such as the James Webb Space Telescope (JWST), which is due to be launched later this year. These planets all orbit red dwarf stars between 35-150 light years away: close by astronomical standards. Already planned JWST observations of the most promising candidate, K2-18b, could lead to the detection of one or more biosignature molecules.

“A biosignature detection would transform our understanding of life in the universe,” said Madhusudhan. “We need to be open about where we expect to find life and what form that life could take, as nature continues to surprise us in often unimaginable ways.”