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To find out what happens at the centre of a black hole, we may need to consider its event horizon - and think about where we're looking from, says Chanda Prescod-Weinstein

Feedback is amused that marine researchers worried about microplastics dressed up as coral polyps and a Greek sea goddess to visit a Comic-Con. Their awareness-raising went down a storm

Ants and other insects are capable of astounding navigational feats. Perhaps an appreciation of this could aid conservation efforts, says Robert Barrie

Anil Ananthaswamy's Why Machines Learn: The elegant maths behind modern AI explores the mechanics of the AI revolution, but doesn't examine its ethics

Events like the Olympics and Paralympics can be inspiring. But to get more kids moving, we need to address the "enjoyment gap" by shifting the emphasis from competitive sport to activity and play

Characterizing near-Earths asteroids (NEAs) is critical if we hope to eventually stop one from hitting us. But so far, missions to do so have been expensive, which is never good for space exploration. So a team led by Patrick Bambach of the Max Planck Institute for Solar System Research in Germany developed a mission concept that utilizes a relatively inexpensive 6U CubeSat (or, more accurately, two of them) to characterize the interior of NEAs that would cost only a fraction of the price of previous missions. 

The mission, known as the Deep Interior Scanning CubeSat mission to a rubble pile near-Earth asteroid, or DISCUS, was initially floated in 2018. Its central architecture involves two separate 6U CubeSats equipped with a powerful radar. They would travel to opposite sides of an NEA and direct a radar to pass through the NEA’s interior.

To understand more about the mission architecture, it’s best to look at the type of asteroid best suited to being visited by DISCUS. The authors suggest one about the size of Itokawa, the target of the first Hayabusa mission. It’s about 330 meters in diameter, right in the size range the mission planners were looking for, and is designated as a “rubble pile,” meaning the interior is relatively sparse.

Understanding how to stop an asteroid strike is one of DISCUS’s primary mission drivers. Fraser discusses how we can do it.

A sparse interior is critical to the mission objectives, as an asteroid’s density can dramatically impact the scientific toolkit needed to characterize it. For DISCUS, the mission team plans a radar antenna known as a half-dipole. This would transmit at a relatively low frequency, which is more likely to pass through larger objects. Additionally, they plan to use a radar technique known as stepped-frequency modulation, which changes the radar’s frequency to allow for the broadest range of characterizations.

The opposing spacecraft on the other side of the asteroid would then receive these radar signals, analyze whatever waveform deformations occurred, and correlate that to the materials the radar had to pass through. Calculations show that this technique should enable a resolution of a few tens of meters for the interior of an asteroid about the size of Itokawa.

However, they also have to be run through another spectral analysis technique called computed radar tomography. This technique is often used in radiology diagnoses on Earth—the name CT scan comes from—but it can also be used to analyze the interiors of solid objects in the solar system.

The radar techniques DISCUS uses are also used on Earth, as described in this video on bistatic radar.
Credit – Nicole Bienert YouTube Channel

However, the science payload is only one part of the DISCUS package and would ideally only take up 1U of the 6U allotted on each probe. The other five would be taken up by a series of off-the-shelf components, including a propulsion system (2U), communication system (1U), and avionics suite (1U). The dipole antenna and solar panels would deploy outside the standard CubeSat housing, allowing for better power collection and signal strength.

One of the most critical selections is the propulsion system, which would enable an acceleration of around 3.2 km/s, allowing DISCUS to match speeds with at least some NEAs. Alternatively, the mission plans to slingshot the craft around the Moon to get a boost of up to 4 km/s and gain access to even more asteroids.

A particular asteroid stood out to the team as they developed the mission design in 2018. Asteroid 1993 BX3 came within 18.4 times the distance to the Moon back in 2021 and was traveling at a speed that DISCUS could match, so the mission design team was hoping to have a prototype up and running to allow for a launch to that particular asteroid.

Unfortunately, that didn’t happen, and there hasn’t been much work on the mission concept since the paperback in 2018. However, more and more missions are targeting NEAs, and CubeSats are becoming increasingly popular. Eventually, a CubeSat mission will visit one of these objects and likely will be based at least partially on some ideas from DISCUS.

Learn More:
Bambach et al. – DISCUS – The Deep Interior Scanning CubeSat mission to a rubble pile near-Earth asteroid
UT – Swarms of Orbiting Sensors Could Map An Asteroid’s Surface
UT – Swarming Satellites Could Autonomous Characterize an Asteroid
UT – Asteroid Samples Were Once Part of a Wetter World

Lead Image:
This illustration shows the ESA’s Hera spacecraft and its two CubeSats at the binary asteroid Didymos. Image Credit: ESA

The post A Pair of CubeSats Using Ground Penetrating Radar Could Map The Interior of Near Earth Asteroids appeared first on Universe Today.

You must have experienced this frustration: trying to get those stickers off of individual pieces of fruit without ripping the skin. I suppose it can be done with care, but I don’t have the time. Plus they now have ways to emboss the fruit without stickers, like using lasers.

My lunch apple, before:

My lunch apple, after sticker removal.  The unavoidable crater appears:

Now clearly this isn’t a cosmic issue, but it’s one Andy Rooney would have talked about, and now that he’s gone somebody has to!

Better fitness in children is linked to better cognition and health in later life, but the majority in the US and UK don't get nearly enough. Here's what parents can do

A comment by reader Chris Slater called my attention to this article from GeoNet, an organization described as providing “geological hazard information for Aotearoa New Zealand.”  It’s also

. . . . sponsored by the New Zealand Government through its agencies: Natural Hazards Commission Toka Tū Ake, GNS Science, Toitū Te Whenua Land Information New Zealand (LINZ), the National Emergency Management Agency (NEMA) and the Ministry of Business, Innovation and Employment (MBIE).

The hazards include volcanoes, earthquakes, landslides, and tsunamis.  Useful, right? And of course the monitoring is done using scientific methods (see here for earthquakes, for instance), because you must use modern science to make the best predictions.

But this is New Zealand, and so GeoNet had to drag in some indigenous knowledge to satisfy the Zeitgeist; in this case, the addition was arrant superstition. This article, which you can read by clicking on the headline, invokes gods as a cause of earthquakes.  It’s all metaphor, of course, but it’s done to satisfy the claim that both kinds of “knowledge” is the optimal mixture for understanding the world.

The subheadline echoes the headline:

The weaving together of different knowledge strands, Mātauranga Māori and western science, strengthens our understanding of our whenua (land) and supports conversations on how we can be better prepared for natural hazard events, such as an Alpine Fault earthquake, together.

Note the assertion that combining indigenous “ways of knowing” with what they persist in calling “western science” (which is no longer western) will make for a better understanding of nature.  But Mātauranga Māori doesn’t just include practical knowledge gleaned from trial and error: it also includes superstition, ethics, morality, legend, and religion.  And here they bring in the religion. 

An excerpt (my bolding)

The Alpine Fault is the longest naturally forming straight line on earth. It marks the meeting of two large tectonic plates and has formed over millions of years, stretching longer, lifting our landscape up out of the ocean, and creating the peaks of Kā Tiritiri o te Moana (Southern Alps) with every large earthquake it generates.

According to Ngāi Tahu creation stories, earthquakes are caused by Rūaumoko, the son of Ranginui (the Sky Father) and his wife Papatūanuku (the Earth Mother). Māori have experienced rū whenua, which means ‘the shaking of the land’ for centuries.

Science tells us that Rūaumoko rumbles the Alpine Fault about every 300 years, and the last time was in 1717. These big earthquakes have been happening for millions of years and the next one is not a case of if, but when. The next large Alpine Fault earthquake will be long and strong and significantly alter the landscape of Te Waipounamu as we know it. Landslides, liquefaction, river changes, flooding, tsunami, and aftershocks are all likely.

A large Alpine Fault earthquake happening in our lifetimes is no doubt a scary thought! However, understanding how our whenua has moved in the past helps us prepare to move with it in the future. While we can’t predict when it will happen, we can work together to be better prepared for it by sharing our mātauranga (knowledge), science, and experiences of past earthquakes and emergencies to raise awareness, build understanding, and strengthen our relationships. The better connected we are beforehand, the easier it will be to support each other during and after a catastrophic event.

This is a hot mess.  Dragging in Māori religion not only doesn’t add anything to the prediction of earthquakes, but is likely to confuse students who think that religious mythology is inherent in this prediction. What on earth can it mean to say that “Science tells us that Rūaumoko rumbles the Alpine Fault about every 300 years. . “?  That is simply a flat-out lie.  The pressures on the tectonic plates makes them slip roughly once every 300 years. It’s not due to the actions of a god who decides to rumble the earth about every 300 years (does he get bored?).

It is a disservice—in fact, an insult—to geologists to add to their science the idea that gods are shaking the earth. It is an embarrassment to New Zealand’s government that they are more or less forced to mix indigenous myths with science to pretend that they can reinforce each other. And that pressure comes from trying to sacralize the indigenous people and satisfy, so they think, are the demands of the 1840 Treaty of Waitangi. But that treaty says nothing about indigenous ways of knowing being made coequal to modern science.

Yes, indigenous knowledge may be a useful addition to some limited scientific endeavors, but this is not one of them. Get the gods out of geology!

A tunable metasurface can control optical light in space and time, offering a path toward new ways of wirelessly and securely transmitting large amounts of data both on Earth and in space.

A tunable metasurface can control optical light in space and time, offering a path toward new ways of wirelessly and securely transmitting large amounts of data both on Earth and in space.

Ultrafine particles, UFPs, the smallest contributors to air pollution, hinder the function of mitochondria in human olfactory mucosa cells, a new study shows. The study showed that traffic-related UFPs impair mitochondrial functions in primary human olfactory mucosa cells by hampering oxidative phosphorylation and redox balance.

Chemists have for the first time established how Rembrandt applied special arsenic sulfide pigments to create a 'golden' paint.

Novel porous crystalline solid shows promise as an efficient and durable material for ammonia (NH3) capture and storage, report scientists. Made through a simple reprecipitation process, the proposed organic compound can reversibly adsorb and release NH3 via simple pressurization and decompression at room temperature. Its stability and cost-effectiveness make this material a promising energy carrier for future hydrogen economies.

Using the James Webb Space Telescope (JWST), astronomers imaged a new exoplanet that orbits a star in the nearby triple system Epsilon Indi. The planet is a cold super-Jupiter exhibiting a temperature of around 0 degrees Celsius and a wide orbit comparable to that of Neptune around the Sun. This measurement was only possible thanks to JWST's unprecedented imaging capabilities in the thermal infrared. It exemplifies the potential of finding many more such planets similar to Jupiter in mass, temperature, and orbit. Studying them will improve our knowledge of how gas giants form and evolve in time.

The 166-million-year-old fossils of an adult and a juvenile of the same extinct mammal species reveal that they had longer "childhoods" and lifespans than similar species today

Methane, a potent greenhouse gas, is converted to CO2 by microbes in tree bark, meaning trees are even better for the climate than we thought

When we take a break from exercise, it can feel like we quickly go back to square one. But this isn't the case, and there are various ways to minimise the decline

Today’s Jesus and Mo strip, called “Trump“, came with a short summary: “God wants you to stop projecting your own desires onto him.”

Clearly Mo is a Democrat!  But of course, anybody who wishes that Trump had been killed is morally off the rails, though I’ve heard that from a few people.

A brain circuit discovered in mice could explain why placebo treatments ease pain in people