Are Water Bears True Bears?

By Rida Fatima

Tardigrade
(Credit: Eye of Science/Science Photo Library)

Why do water bears exist? Are those bears actually there? It’s simple to respond “no,” as the only similarity between water bears and bears are that they are both animals. Water bears have a morphology that is somewhat similar to that of true bears, like the polar bear or the grizzly, but they are most closely linked to the enormous group of organisms known as the arthropods. This group of creatures, which consists of insects, spiders, millipedes, and crabs, is distinguished by its exoskeleton. However, due to their small size, water bears are invisible to the unaided eye. Their typical size is 1 mm. Over 200 years have passed since the discovery of water bears. They were first referred to as “little water bears” by German pastor and biologist Johann Goeze because of their diminutive size and fondness for wet conditions (Elleuche, 2021)

Water bear Size Comparison
(Figure 1: Tardigrades are extremely small compared to other animals. The water bear micrograph by Bob Goldstein and Vicky Madden/grasshopper and the cat photograph by S. Elleuche)

Why water bears are considered as best animals to be sent on mars?

It is known that some microorganisms, including as bacteria, algae, fungi, and archaea, can endure the extreme environments found on other planets and/or moons (e.g. on Mars). Would it also be feasible with regard to higher organisms, such as animals? Specifically, tiny invertebrates called tardigrades? Mars is a relatively unfavorable environment for invertebrates from Earth because of its nearly nonexistent atmosphere, extremely low atmospheric pressure and temperatures, absence of liquid water, and significant doses of cosmic, ionizing, and UV radiation. On the other hand, it is still likely the Solar System location that is friendliest to terrestrial life (apart from the Earth). Numerous studies have demonstrated that nematodes, rotifers, and of course tardigrades are among a few types of cryptobiotic invertebrates that are the best prospects to thrive in Martian circumstances. More than 1,200 species of water bears make up the Phylum Tardigrada (water bears), which can be found in practically every terrestrial, freshwater, and marine ecosystem on Earth, from the deepest oceans to the highest mountains. Studies on survival in harsh environments frequently employ tardigrades as a model multicellular organism because they are among the strongest metazoans on Earth.

Tardigrades in extreme environments
(Figure 2: Tardigrades in extreme environments. Łukasz Kaczmarek photo taken during the research.)

The capacity of tardigrades to enter cryptobiosis is responsible for their extraordinary resistance to harmful environments. The metabolic processes dramatically slow down or even stop in this state. Numerous studies shown that water bears are remarkably resilient to a wide range of environmental stresses, including a lack of liquid water, extremely high and low pressures, radiation, and numerous chemicals. Can we now question if this is sufficient for Mars survival? Additionally, studies have been carried out within the context of BARg operations (Biodiversity and Astrobiology Research group) (Kaczmarek, 2017).

Water Bear Genes Could Help Protect Space Explorers From Radiation

The genes that enable the resilient water bear to survive such extremes have been identified in a new analysis of the tardigrade genome, which may have ramifications for upcoming human space flight. One of the more resilient tardigrade species, Ramazzottius varieornatus, had its DNA examined by scientists from the University of Tokyo. They discovered numerous distinctive features of the genome through this study, including more copies of an antioxidant enzyme and a protein repair gene than were discovered in any other mammal. However, the gene of particular relevance codes for a protein that is specific to the species and probably shields it from radiation. The protein helps to repair radiation damage in addition to shielding the DNA in tardigrade cells from harmful radiation (Daley, 2016).

X-ray-damaged DNA is protected and repaired by a protein generated by the microscopic but tough tardigrades.

At first, it didn’t seem to matter that the scientists transplanted Dsup to grown human cells. The discrepancy, however, was “kept in the incubator for a time with the expectation that the difference would eventually become extremely obvious and that a critical attribute of Dsup lay concealed somewhere in that microscopic difference.” When the cells were reexamined under the microscope a while later, much to our great astonishment, their form and number had altered dramatically, exceeding our expectations. Particularly, over time, the Dsup assisted in DNA repair. This could be a significant advancement in the protection of human astronauts who would be exposed to high levels of cosmic radiation on upcoming missions to Mars and other planets. However, at the moment, it required genetic alterations to do this, which is not going to happen anytime soon. “Once Dsup can be introduced into people, it probably can enhance radio-tolerance”. The protein, according to the researchers, only provides about half the necessary protection, and it’s probable that the tardigrade uses additional defense mechanisms to defend itself from radiation. (Daley, 2016).

The discovery also settles a dispute that arose a year ago after a group of researchers from the University of North Carolina, Chapel Hill, published research asserting tardigrades have amassed roughly around 6000 genes from archaea, bacteria, fungus, and plants which are accounting for nearly 1/6th of the total genome. Furthermore, the concept was that through a process called as horizontal transfer, this particular specie had “borrowed” the genes that gave it its abilities from many other different species. However, after a back-and-forth with some other team that differed with the findings, the researchers rapidly came to the conclusion that the bulk of those genes were a result of contamination during the investigation. This new study took extra efforts to avoid contamination and examined genes obtained through horizontal transfer as well. According to their research, 1.2% of tardigrade genetic material originates from other species, which is not unusual in the animal realm (Daley, 2016). This fact highlights how remarkable the water bears are. Most of these extraordinary talents were independently developed by tardigrades.

References

China Mars Mission, Tianwen-1 Arrives in Orbit

Tianwen-1 Team
(Image Credit: China Aerospace Science and Technology Corporation (CASC))

Hot on the heels of the UAE mission which arrived earlier this week, the Chinese Tianwen-1 mission has also arrived at the red planet and entered orbit. Meaning “Questions to Heaven”, this mission will further extend our knowledge of our new frontier when the second phase lands a rover on the planet, designed to use ground-penetrating radar to learn more about the geological structure. Meanwhile, the orbiter will continue to study the planet using seven remote sensing devices.

Tianwen-1 Orbiter Instruments

A new Space Race is exactly what our struggling world needs right now. My hope is that we can see a new era of cooperation and scientific competition, from which will arise new technologies, new partnerships and a unity that we are sorely lacking. I am firmly convinced that, as nations continue to mount efforts such as this to study the planet, SpaceX will succeed in delivering the capability to get cargo and shortly there after, crew sent to our new home. Much like the Space Station, where astronauts from different nations come together to work and experience the awe of space travel, national boundaries become meaningless during such endeavors. This is sure to be true on Mars as well, where the urgency of research and survival will outshine petty politics that are then millions of miles away.

See this excellent eoportal resource for solid background on the mission.

References:

SpaceX Falcon 9 Launch 1:18am Eastern, August 7th 2018

I think that Brian Shields from Orlando’s WFTV 9 said it best: “Who’s staying up tonight!”

I’m really delighted to see how excited the local news is in Florida. I like to think that after nearly a decade of downtime since the Shuttle was mothballed, and far more years than that since there was palpable excitement across the country and the world for the promise of space flight, they are delighted to see this industry returning to their area, and with real conviction!

This flight is important, because it is the first reuse of their new Block 5 model first stage booster. Specifically, this will be the second flight of booster B1046, which was first flown on May 11th 2018 for Bangabandhu-1, Bangladesh’s first communications satellite.

So – stay up, or set an alarm, for the Merah Putih mission! (press kit)

References:

Mars Dust Storm and the Stalwart Opportunity

Mars Dust Storm 6/6/2018
(Image Credit: Mars Reconnaissance Orbiter)

Owing to the major differences between ostensibly similar planets of Earth and Mars, the red planet is now experiencing a massive dust storm the size of North America. Right in the midst of this maelstrom is the little Opportunity rover, hunkered down as best as it can against the fury of the bringer of war.

What is truly amazing, however, is that the rover is expected to weather the storm with little difficulty, only experiencing a brief suspension of it’s ongoing mission objectives.

The large concerns in a situation like this, of course, are that the solar panels may become covered with too much dust to properly funciton, or that the sun is obscured for too long causing a sharp decline in temperature of the rover. Neither eventuality is expected to slow down the scrappy piece of tech, and NASA appears to be in good shape to claim yet another of the ongoing victories in their rover program.

Reference: cnet

SpaceX Block 5 Launch set for 4:12pm EDT today

Drone Ship: Just Read the Instructions
(Image Credit: SpaceX)
Watch Live – current liftoff target is 5:47pm EDT.

A quick note that the SpaceX Block 5 launch, which we have been tracking and very excited for, is scheduled for 4:12pm EDT this afternoon! It will be launching the Bangabandhu 1 communications satellite for the government of Bangladesh from NASA’s Kennedy Space Center in Florida. The plan is to land this new and improved booster on the drone ship “Of Course I Still Love You” which is stationed in the Atlantic patiently waiting. We hear reports of heavy seas, so hopefully the four diesel powered azimuth thrusters are up to the challenge!

NASA’s InSight Mars Lander Launch Preparations

NASA InSight Lander attaches to Atlas 5 Rocket

The InSight Mars Lander has been connected to the Atlas 5 rocket at Space Launch Complex 3-East Vandenberg Air Force Base, with a projected launch window of May 5th – June 8th. Regardless of when during that window the rocket flies, the lander is scheduled to arrive at Mars on November 26th. This close alignment of Earth and Mars which allows for a direct trip, only happens for this window of time once every 26 months.

The mission of the InSight lander (aka Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) is to study the crust, mantle and core of the red planet to learn more about the early formation of planets in our solar system. This launch will also send two ‘CubeSat’s to space, where they will follow InSight to Mars and provide essential communication services.

Now that human spaceflight to Mars is seeming more and more realistic, it’s fun to closely observe a new launch like this, and to realize that while it’s still a long trip, it is not a year of travel. Before you even have a chance to get through your collected works of Shakespeare on your tablet or re-calibrate the hydroponics systems to optimize lettuce production, it will be time to buckle up for landing!

(Thanks to spaceflightnow.com for the excellent discussion of this new NASA lander)

Mars – Trace Gas Orbiter

Trace Gas Orbiter
(Paris Air Show, 2015)

The Trace Gas Orbiter, which is part of a joint venture between the European Space Agency (ESA) and the Russian space agency Roscosmos, has been orbiting Mars for over a year and is now in position to begin its research. These readings and results started to be gathered on April 21st and are now flowing back home for analysis and review.

Specifically, this probe is investigating the methane which is present in the Martian atmosphere, because it is very often associated with the former (or current!) presence of life. On Earth, an overwhelming percentage of the available methane is the result of biological processes. To add stakes to the game, current scientific understanding of the Martian atmosphere says that what is there should be destroyed by ongoing chemical reactions in several hundred years, though there it remains.

The orbiter has 2 main scientific instruments through which it will make this survey:
* the main spectrometer, NOMAD, operates in the infrared, ultraviolet and visible parts of the electromagnetic spectrum.
* the color camera, CaSSIS, will build detailed 3D maps of the planet’s terrain.

The craft will eventually serve in a new capacity as a communications depot once the ExoMars Rover arrives in 2021, relaying signals from the ground based explorer back to mission control.

Mars Terrain Exhibiting Familiar Earth Effect

Mars Frost Heaves
One of the hesitations to considering life on other worlds, for many, will be how to cope with the truly unsettling experience of leaving behind everything you know in exchange for an alien landscape. Well, our nearby neighbor may be more welcoming than many realize, if only you take the time to appreciate the little things. Take, for example, the new beautiful image from the Mars Reconnaissance Orbiter which appears to show a familiar process of frost heaves, which has led to boulders being forced to the surface.

So, now you can have a blue sunset, frost heaves, and a giant statue of Elon Musk in the town square. What more can you ask for.
(Quartz Media LLC)