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Marsquakes caused by tectonic activity, NASA’s InSight probe confirms – BBC Focus Magazine

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  • NASA’s InSight probe confirms that Mars’ quakes are caused by the movement of tectonic plates.
  • InSight has detected more that 450 quakes on Mars since it arrived in November 2018.
  • The probe also finds that the local magnetic field is 10 times stronger than expected.
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A NASA spacecraft sent to study the deep interior of Mars has confirmed the planet to be seismically active, or in other words, prone to quakes.

The spacecraft, called InSight, successfully touched down in the Elysium Planitia region of the Red Planet in November 2018 after travelling 300 million miles through space for almost seven months.

Scientists say understanding more about the seismic activity of planets other than Earth could reveal clues about how the Solar System formed.

Dr Bruce Banerdt, InSight principal investigator and lead author on one of the studies, said: “We finally have, for the first time, established that Mars is a seismically active planet.”

Read more about the InSight mission:

The first so-called “Marsquake” was recorded by InSight’s onboard sensors in April 2019. Since then, it has detected more than 450 quivers, much smaller than anything that would be felt on Earth.  But two of them were big enough for scientists to be able to trace them back to their source. They came from a geologically active area known as Cerberus Fossae, around 1,000 miles east of Elysium Planitia.

The InSight lander © PA Science

Researchers say this provides strong evidence that seismic activity on Mars is not only a consequence of the cooling and shrinking of the planet but also caused by tectonic plates running into each other or moving apart. The seismic energy released on Mars is something between that of the Earth and the Moon, the researchers said.

Dr Domenico Giardini, of ETH Zurich in Switzerland and lead author on one of the studies, added: “Marsquakes have characteristics already observed on the Moon during the Apollo era, with a long signal duration (10 to 20 minutes) due to the scattering properties of the Martian crust.”

The scientists hope reading the seismic waves on Mars will reveal information about what the planet’s interior looks like and how it is changing.

The findings also suggest a local magnetic field at the landing site that is 10 times stronger than anticipated. In addition, the researchers found Martian weather to be similar to that of Earth but with key differences, such as stronger daily atmospheric pressure and temperature fluctuations.

Nasa’s InSight lander © NASA/JPL-Caltech
Nasa’s InSight lander © NASA/JPL-Caltech

Dr Don Banfield, of the Centre for Astrophysics and Planetary Science at Cornell University in the US and a lead author on one of the studies, told the PA news agency: “The atmosphere is so thin that it can heat up and cool down much faster than Earth’s. At night, it cools to as low as about -95°C, while in daytime, it reaches temperatures near 0°C.”

Evidence of dust devils, which are whirls of Martian soil whipped up by the wind that spin like a tornado at nearly 60mph, were observed a month after InSight touched down on Mars.

Read more about Mars:

The team also detected a phenomenon known as “gravity waves”, which Dr Banfield described as “buoyancy oscillations of air parcels also observed regularly on Earth”. He told PA: “We are still working to understand what these waves can teach us about Mars. This will likely receive lots of attention over the coming years.”

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Preliminary findings from InSight’s first 10 months on Mars are published in a series of papers in Nature research journals. The £633 million NASA mission is expected to continue for another year.

Reader Q&A: Do all planets have magnetic fields?

Asked by: Daniel J Buhs, US

No, not all planets have magnetic fields. The four gas giants have extremely strong magnetic fields, Earth has a moderately strong magnetic field, Mercury has an extremely weak field, but Venus and Mars have almost no measurable fields.

Planetary magnetic fields are formed by the interaction between the convection of interior conducting material (molten rock and metal) and the planet’s own rotation. Mercury’s field is weak because it rotates so slowly. Venus doesn’t have an appreciable field because there appears to be little convection in its molten interior. Mars doesn’t have an appreciable field – although it did in the past – because its interior has solidified.

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Want to Buy Flights on Starship? Here's the New SpaceX Payload User's Guide, no Prices, Unfortunately – Universe Today

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The development of the Starship – SpaceX’s super-heavy launch system that will take cargo and crews to orbit, the Moon, and even Mars – has been fraught with setbacks and frustration. But Musk has no intention of stopping and is even planning ahead for the day when the Starship and Super Heavy are making regular flights.

In keeping with this, SpaceX recently released a Payload User’s Guide for consumers that lays out what kind of services the launch system will provide – once it’s up and running. While no price points have been established yet, the guide provides a good summary of the Starship’s technical specifications and capabilities.

These are summarized early in the guide, where it states that “Starship has the capability to transport satellites, payloads, crew, and cargo to a variety of orbits and Earth, Lunar, or Martian landing sites… The uncrewed Starship allows for the transport of satellites, large observatories, cargo, refueling tanks or other unmanned assets.”

Artist’s impression of SpaceX’s Starship deploying cargo to Low Earth Orbit (LEO). Credit: SpaceX

What follows is a detailed treatment of the Starship‘s payload fairing’s interface. The fairing is described as a “clamshell structure” that contains an integrator and remains closed until the time of deployment. Measuring 9 meters (29.5 ft) in diameter from the outside, SpaceX claims their fairing is “the largest usable payload volume of any current or in development launcher.”

The guide goes on to say that the geometry of the Starship allows for a 22 m (72 ft) extended payload volume, which can facilitate of novel payloads, rideshare opportunities, and the deployment of entire constellations of satellites (such as SpaceX’s Starlink internet satellites) in a single launch.

The spacecraft also takes a page from NASA’s Space Shuttle, offering the option of placing trunnion-style interfaces on the surface of the interior to accommodate more cargo. Attention is also given to how the launch system will also accommodate standard payload interface systems and electrical interfaces.

The guide then goes on to describe the payload environment in terms of its ability to handle axial and lateral accelerations (which will range from -2 g to 6 g axially and -2 g to 2 g laterally) as well as acoustics and shocks.

Artist’s rendering of a Starship taking off from a lunar base. Credit: SpaceX

In this respect, SpaceX is relying on industry standards and their own experience with the Falcon family of rockets (particularly the Falcon Heavy):

“Utilizing strong heritage and lessons learned from the development of the Falcon 1, Falcon 9 and Falcon Heavy launch systems, SpaceX is designing Starship and Super Heavy to provide as benign of a payload environment as possible.”

What follows, predictably, is a rundown of the launch system’s mass-to-orbit capabilities, based on the absence and presence of parking orbit refueling (POR). To Low Earth Orbit (LEO), which they define as a circular orbit of up to 500 km (310 mi), which in both cases would exceed 100 metric tons (110 US tons).

To Geostationary Transfer Orbit (GTO), the system will be able to send 21 metric tons (23 US tons) without POR and over 100 with it. Potential landing sites are also specified for missions that require payload returns. They include SpaceX’s existing facilities at the Kennedy Space Center in Florida and Boca Chica, Texas.

As for payload deliveries to the Moon and Mars, they indicate that “Starship was designed from the onset to be able to carry more than 100 tons of cargo to Mars and the Moon.”

Artist’s illustration of a SpaceX Starship lands on Mars. Credit: SpaceX

As for crewed missions, that’s where things get especially interesting. In keeping with SpaceX’s vision of making life “multi-planetary,” the Starship crew configuration emphasizes moving people in style. As they wrote:

“Drawing on experience from the development of Dragon for the Commercial Crew Program, the Starship crew configuration can transport up to 100 people from Earth into LEO and on to the Moon and Mars. The crew configuration of Starship includes private cabins, large common areas, centralized storage, solar storm shelters and a viewing gallery.”

No price information is available yet, but since the launch system is intended to be entirely-reusable, one has to assume it will be competitive with other launch services (and even SpaceX’s previous launch vehicles). What’s more, cost-effectiveness is something that is written right into SpaceX’s mission statement.

At present, it remains unknown when the Starship and Super-Heavy will begin making commercial flights. With the issues they’ve been experiencing testing the Starship prototypes, it is clear that the 2022 deadline for missions to the Moon may not happen. However, Musk is known for being optimistic about his timelines, not to mention his tenacity and perseverance in the face of setbacks.

Further Reading: SpaceX

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SpaceX's Third Starship Prototype Collapsed Last Night – Universe Today

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Top Image Credit: LabPadre w/ Maria Pointer

SpaceX just cannot catch a break! Last night, during the same cryogenic proof test that killed the previous two prototypes, SpaceX’s SN3 prototype experienced a structural failure. On-site video footage provided by famed NASASpaceFlight member BocaChicaGal shows the SN3 experiencing what appears to be a leak, followed by the fuselage collapsing.

The cryogenic proof test consists of the vehicle’s fuel tanks being filled to capacity with nitrogen (and sometimes oxygen) that is cooled to cryogenic temperatures. This test is carried out after an ambient pressure test, where the vehicle is filled with gas at room temperature to see if it can handle the kinds of pressure conditions it will experience during flight.

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The test began late on Thursday (April 2nd) and continued into the morning until the SN3 suffered a rupture during what appeared to be the end of the test. This comes a little over a month after the second prototype (SN1) exploded on the Boca Chica facility’s launch pad on the evening of Feb. 28th, 2020, during a similar cryogenic proof test.

During that test, the liquid oxygen tanks blew out the bulkhead, which sent the vehicle’s fuselage to collapse inward and jump several meters into the air. The wrecked prototype then fell to the landing pad on its side, followed shortly thereafter by the methane tanks exploding out of the top bulkhead and flying 150 to 300 meters (500 – 1000 ft) from the pad.

The previous failure (also experienced during the cryogenic proof test) happened on November 20th, 2019. At this time, the Mk. 1 prototype suffered a failure that caused its top bulkhead to explode (and the nose cone to be hurled beyond the facility) followed by a secondary explosion from the bottom bulkhead.

In response to both incidents, Musk responded by saying that these types of failures are expected during load tests and would provide information vital to the construction of future prototypes. In fact, the design of the SN3 (Serial incorporated lessons learned from these two previous vehicles and took advantage of improved manufacturing techniques, where each ring consisted of a single welded piece of steel.

Another notable feature on the SN3 was the new, internally mounted deployable leg design, which was visible in photos shared by Musk via Twitter on March 30th. These legs were included to accommodate the short hop test flights that the SN3 would have conducted. Musk noted at the time that the legs would be longer with the SN4 and subsequent prototypes since they would be making higher flights.

Responding to this latest setback, Musks tweeted, “We will see what data review says in the morning, but this may have been a test configuration mistake.” This was posted to his official Twitter account in the early morning hours of April. 3rd. About ten hours prior, he related how the SN3 passed its ambient temperature pressure test the night before and that they were proceeding to the cryogenic test.

Four hours after that, he tweeted, “Some valves leaked at cryo temp. Fixing & will retest soon.” These tests took place just a week after the SN3 underwent final assembly and was delivered to the test facility in Boca Chica, events that were shared by Musk and LabPadre via Twitter. LabPadre was also on hand to witness the rupture experienced by SN3 and captured it on video (shown below).

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At the time, it was clear that Musk intended to move ahead with testing as quickly as possible. Had things gone as planned and the SN3 passed the cryogenic proof test, Musk and his teams of engineers at Boca Chica would have proceeded with a static fire test, followed by a hop test that would see the prototype fly to an altitude of 150 m (500 ft), the same height achieved by the Starship Hopper.

These were originally scheduled to take place between April 1st and April 3rd (static fire test) and April 6 to April 8 for the flight test. However, those timelines were contingent on the successful completion of the cryogenic proof test. As he did after the previous failures, Musk has stated that rather than attempt to salvage the wrecked prototype, his company will be proceeding with the construction of the next vehicle (SN4).

This prototype has already begun construction at Boca Chica and was visible during the ambient temperature pressure test on Thursday, April 2nd. It is unclear right now when it will be assembled and put through its paces, but it seems likely at this point that the 150-m flight tests SpaceX hoped to make with SN3 will now be performed by SN4.

Of course, we should remind ourselves that test likes these happen for a reason. In short, they ensure that failure does not take place during a crucial point – like a crewed mission! In the meantime, onwards and upwards for the Starship and SpaceX!

Further Reading: NASA SpaceFlight

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Great Barrier Reef endures third mass bleaching event in five years – The Weather Network

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Scientists that are monitoring the Great Barrier Reef in Australia report that it has suffered its third mass bleaching event in five years. The reef is considered to be the largest living structure in the world, but warming temperatures are straining the corals and are causing these bleaching events to become increasingly common.

A study that was published in April 2018 found that half of the Great Barrier Reef had died since 2016 when this region of the world experienced abnormally warm temperatures. The El Niño and La Niña weather patterns contributed to the extreme conditions, however, neither event was occurring when this year’s mass bleaching took place.


Bleached branching coral (foreground) and normal branching coral (background). Keppel Islands in the Great Barrier Reef. Credit: Acropora/ Wikimedia Commons. CC BY-SA 3.0

Oceans cover over 70 per cent of the Earth’s surface and have the capacity to store more than 1,000 times the amount of heat than the atmosphere, which is why aquatic environments are particularly sensitive to the greenhouse gas emissions we release.

Corals start to bleach when the water becomes too hot and causes them to expel the colourful algae that live on them. The coral relies on the algae because it is their primary food source, while the coral provides the algae with a protected environment and nutrients needed for photosynthesis. The absence of the colourful algae leaves the coral with a stark white appearance.

HOW WE CAN PROTECT MARINE ECOSYSTEMS

The ecosystems within oceans are complex and can stretch over vast areas, making conservation efforts unique and specific for each region. While the frequency of mass bleachings is worrisome, the good news is that coral reefs can recover if temperatures return back to normal.

Marine experts face many decisions when choosing how to best protect coral reefs and have found that increased monitoring and involvement from local governments and communities have been key factors in successful coral reef conservation projects.

See below for a look at the inspiring work that organizations are doing to conserve coral reefs across the world.

USAID Project REGENERATE, Maldives

The Maldives is a low-lying atoll nation in the Indian Ocean and their economy largely relies on coral reefs for their tourism and fishing industries. Despite experiencing mass bleachings in 1998, 2010, and 2016, the IUCN says that these coral reefs have shown a “great capacity for resilience.”

Maldives coral wiki cc
Coral reef in the Maldives. Credit: Tchami/ Wikimedia Commons. CC BY 2.0

Project REGENERATE is funded by the United States Agency for International Development (USAID) and helps local governments and researchers access science and technology and use education and monitoring while providing sustainable financing mechanisms to support resilient marine management.

Southern Leyte Coral Reef Conservation Project (LRCP), Philippines

Coral reefs located in the Southern Leyte province in the Philippines host some of the most biodiverse marine habitats in the world, but face many stressors including abnormally warm temperatures and pollution.

philippines coral reef wiki cc
A shark swimming through Tubbataha Reefs Natural Park, which is a protected area of the Philippines in the middle of the Sulu Sea. Credit: Nikswieweg/ Wikimedia Commons. CC BY-SA 3.0

Since 2002 the LRCP has worked with local stakeholders and researchers to increase data collection. The organization’s website says that learning more about the reefs will indicate how protected areas improve biodiversity and handle stressors that cannot be controlled, such as atmospheric temperatures.

North Bali Reef Conservation, Bali – Indonesia

Tianyar is a small fishing village on the northeastern coast of Bali and community work there is slowly repairing the damage that coral reefs have sustained over the past century. The North Bali Reef Conservation’s website says in the early 1900s coral was harvested and crushed into a fine white powder that would be painted onto homes of the wealthy. Pollution and disruption from the fishing industry have added further stress to reefs that were previously harvested or damaged by anchors dropped by visiting boats.

coral reef indonesia wiki cc
Coral reef in Indonesia. Credit: Nick Hobgood/ Wikimedia Commons. CC BY-SA 3.0

Some of the successful initiatives that the organization has created include a community recycling centre and the installation of over 3,000 artificial reefs that expand the habitat for many aquatic species.

Reef Rescuers, Seychelles

A mass bleaching event in 1998 killed up to 90 per cent of the coral reefs in some areas in Seychelles due to unusually warm temperatures. The reefs suffered another bleaching event in 2016, but by this point, the Reef Rescuers project was already underway.

seychelles wiki cc
Anse Source d’Argent, Seychelles. Credit: dronepicr/ Wikimedia Commons. CC BY 2.0

The project launched in 2010 and their website states that they were the world’s first large-scale coral reef restoration project. Their “coral gardening” technique involves collecting coral fragments from healthy sites, growing these fragments in underwater nurseries to maturity, and then replanting them into degraded reefs. They have successfully transplanted over 24,000 corals and have welcomed dozens of scientific divers from around the world to study their successful restoration techniques.

RangerBot, Great Barrier Reef, Australia

The Great Barrier Reef foundation designed the Rangerbot, which is the “world’s first autonomous underwater drone” that is dedicated to protecting coral reefs. This unique machine was designed to meet the foundation’s most pressing needs and is able to map expansive underwater areas, monitor coral bleaching indicators and water quality, and control pests like the Crown-Of-Thorns Starfish.

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The Crown-Of-Thorns Starfish resembles the biblical crown of thorns and is one of the largest starfish in the world. Credit: Matt Wright/ Wikimedia Commons. CC BY 2.5

In addition to the stress from warming temperatures, booming populations of Crown-Of-Thorns Starfish are challenging the Great Barrier Reef. These coral-eating starfish are not an invasive species but have been responsible for destroying significant amounts of coral reef. RangerBot is able to control the pests’ population by locating the starfish with SONAR and multiple cameras. The Crown-Of-Thorns are subsequently killed with a lethal injection from RangerBot.

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