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  • Writer's pictureMatt Russell

#191 - John Kiss - To Boldly Grow

This week we are joined by John Kiss, Professor & Dean of the College of Arts & Sciences at UNCG to talk about growing plants in Space. We first take a look at some rocket news and the latest news on the mass gap.

“This nebula had such a resemblance to a comet in its form and brightness that I endeavoured to find others so that astronomers would not confuse these same nebulae with comets just beginning to shine”

Born OTD 290 years ago!!! Charles Messier 26 June 1730 the French astronomer who published an astronomical catalogue consisting of 110 nebulae and faint star clusters, which came to be known as the Messier objects.

Adelaide Ames (June 3, 1900 – June 26, 1932) the American astronomer and research assistant at Harvard University her study of galaxies Brighter Than the Thirteenth Magnitude, became the Shapley-Ames catalogue. Cecilia Payne-Gaposchkin was her close friend


John Kiss

John’s research focuses on the gravitational and space biology of plants, and he has published 112 peer-reviewed papers. He also has been invited to present seminars based on his research at universities throughout the US and in another 12 countries. He served as PI on grants from NASA, USDA, NSF, and the NIH (career total = $6.0 million) as well as PI on eight spaceflight experiments on the Space Shuttle and the International Space Station. In 2014, he received the NASA Outstanding Public Leadership Medal “for exceptional contributions in spaceflight research in the fundamental biology of plants in support of NASA’s exploration mission.”


Few bits of news.

NASA will rename its Washington headquarters after its first black female engineer, Mary Jackson, whose story was told in the hit film "Hidden Figures."


Musk Crew dragon smashing it!

Solar panels producing more power than expected, could stay at the station for a long time, but the astronauts, bob and chunky, will be coming home probably August 2nd and this will speed up the process of validating the Dragon for normal operations. The return should be epic as for the last 9 years we’ve only seen people return to the Russian steps, but this will be a sea drop either off the coast of Florida or Gulf of Mexico.


Relativity Space get another major contract.

Relativity Space the private American company headquartered in Los Angeles founded in 2015 by Tim Ellis and Jordan Noone. The dudes with the most impressive 3D printer EVER. Relativity is developing its own 3D printed launchers and rocket engines for commercial orbital launch services.

Iridium have signed up to launch 6 NEXT sat missions on the Terran 1 launcher from about 2023.

Terran 1 can be 95% printed, the company hope in 60 days. They use the 3D printed Aeon 1 engine, a methane/LOX engine with only 100 parts. This has been tested extensively already. Like a miny Falcon 9 the Terran has 9 engines on the frst stage and 1 on the second and can carry a 1 ¼ tonnes to LEO for about $12 million.

75 NEXT sats went up on seven Falcon 9’s but these NEXT sats are actually spares, that using this cheap non-rideshare option Iridium can launch individual sats to specific orbital planes. Falcon 9 too big fro this and Electron too small, this rocket is in the goldilocks zone as far as Iridium are concerned. It must have helped that Zach Dunn who oversaw the Iridium SpaceX launches has joined Iridium.


Astronomers may have found an object that solves a long mystery. Minding the gap.

In a nut shell, astronomers have found hundreds of black holes and neutrons stars. We reported a few months ago that astronomers had found a really huge Neutron star of about 2.5 Solar masses and this is thought to be approaching a maximum size for such a dense object. But astronomers have not detected any blackholes at a mass below 5 Solar masses. So the question is.

Is there naturally a gap here, that there are no object like Stella remnants between 2.5 and 5 solar masses, or is it a bias in how we discover these objects? Is there really a mass gap, a mass dip, or a straightforward distribution of masses arising from supernova events

Back in 1964, a sounding rocket took off from White sands in new mexico, carrying an instrument designed to map the x-ray emissions coming from space, they are blocked by the earth’s atmosphere. As the rocket rotated it scans the sky and from this geiger counter reading, Astronomers discovered an extremely bright X-Ray source Cygnus X-1 (Yes Rush have a song on the playlist called Cygnus X-1)

NASA launched their Uhuru Satellite in 1970 which led to the discovery of 300 new X-ray sources.

Uhuru is Swahili for Freedom and was chosen because the launch on a scout rocket took place from an Italian facility near Mombasa,

Extended Uhuru observations of Cygnus X-1 showed fluctuations in the X-ray intensity that occurs several times a second. This rapid variation meant that the energy generation must take place over a relatively small region of roughly 100,000 km, as the speed of light restricts communication between more distant regions. For a size comparison, the diameter of the Sun is about 1,400,000 km

1 years later, 1971, Luc Braes and George K. Miley from Leiden Observatory, and independently Robert M. Hjellming and Campbell Wade at the National Radio Astronomy Observatory detected radio emission from Cygnus X-1, and their accurate radio position pinpointed the X-ray source to the star AGK2 +35 1910 = HDE 226868, near Eta Cygni (only from our point of view) It is a supergiant star that is not capable of emitting the detected X-rays. The star must have a companion that could heat gas to the millions of degrees needed to produce the radiation source for Cygnus X-1

Louise Webster and Paul Murdin, at the Royal Greenwich Observatory later that year announced the discovery of this hidden companion, and using the doppler shift of the spectrum calculated the orbital parameters, that meant that this object was much more massive than a Neutron star and by 1973 everyone was in agreement ….This was our First Black Hole!!!! And since has been extensively studied leading to insights into blackholes and Quasars etc.

The Tulip and Cygnus X-1 Image Credit & Copyright: Ivan Eder

Roll on to today and hundreds of pretty much confirmed black holes and thousands of candidates, plus the knowledge that almost all galactic centres have Supermassive Black holes. Ligo has switched on and we have seen the merger of many black holes with many candidates.

So why is it that we have never seen a black hole with a mass less than 5 Solar masses, why would that be, stars don’t have this mass gap, and surely there is a point where Neutron stars spin slows and that causes them to reach a point when they become black holes?

One theory suggests that as Stars go supernova and there cores collapse that as this happens if it’s just enough mass to tip it over into blackhole forming territory then much more mass is withheld in the collapsing core, leaving behind a black hole naturally larger than 5 solar masses. Whereas Neutron star formation doesn’t hover up so much matter leaving you at a maximum 3 solar masses and nothing in-between.

Other theories dispute this, that they do not see a fundamental difference between an object that form an event horizon and those that don’t.

August 2017 the start of multimessenger astronomy we had that event where two Neutron stars merging together, the kilonova!! An event that creates all those heavy elements like gold. These merging Neutron stars formed huge neutron star that collapsed instantly into a black hole,’s mass? the mass gap

So is this the nail in the mass gap coffin, not really it could be that we have black holes in the 2.5 and 2.75 solar mass range caused by neutron star mergers but still have a mass gap caused by Stella collapse that should be visible.

The detection of the huge Neutron stars a few months ago chomped into the mass gap at the bottom end for sure, but it looks like we might have seen a bigger chomp back in November when a paper called. A noninteracting low-mass black hole–giant star binary system by Todd A. Thompson came out. This shows quite compelling evidence from orbital dynamics that a bright, rapidly rotating giant star 2MASS J05215658+4359220 has a companion in the region of 2.6 - 5 solar masses, this companion is dark and unseen and is highly likely to be a black hole. Some astronomers have suggested it might be a low brightness ordinary binary itself, Todd et al dispute this.

But the mystery is not solved of course this black hole could have formed in a Kilonova also.

Roll in the latest disovery

GW190814: Gravitational Waves from the Coalescence of a 23 Solar Mass Black Hole with a 2.6 Solar Mass Compact Object R. Abbott et al

Basically during Ligo/Virgo third observing run on August 14th 2019, there was a merger event between a huge 23 solar mass black hole and something in the region of 2.6 solar Mass region, the most uneven merger so far detected, but this second object also beats another record, It is either the lightest black hole or the heaviest neutron star (Quarkstar even) ever discovered in a double compact-object system. The merger was so distant that even though no light was detected there could have been an xray burst too faint to be detected from a quark star being swallowed by a big black hole.

The combination of mass ratio, component masses, and the inferred merger rate for this event challenges all current models of the formation and mass distribution of compact-object binaries.

This discovery of GW190814 could start to answer this mass gap question of the processes by which the lightest BHs or the most massive NSs form. Based on the inferred rate density estimations in the paper, they expect to detect more systems after a year at design sensitivity.

This discovery may prove to be the first hint of a larger population that could change our perspective on the formation and mass spectrum of compact objects.

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