adplus-dvertising
Connect with us

Science

Building Earth's largest telescope on the far side of the moon – CBC.ca

Published

 on


NASA engineers are studying the feasibility of building a massive, kilometre-wide radio telescope on the moon that would dwarf anything we could build on Earth.

The telescope, which would be constructed by robots, would take the form of a huge, wire-mesh antenna in a dish shape that would hang suspended in a three-kilometre-wide crater on the far side of the moon. 

The Lunar Crater Radio Telescope would provide a unique perspective on the early universe, though it likely won’t be built for decades, according to NASA robotics engineer Saptarshi Bandyopadhyay, who is leading the project.

“We all want to know what happened. How did the universe evolve? What happened after the Big Bang?” Bandyopadhyay told Quirks & Quarks host Bob McDonald.

In the 14 billion years since that event, the light waves from that era have been stretched out from tiny fractions of a millimetre to more than 10 metres as the universe expanded. They’re now extremely long radio waves, and those can’t be seen on Earth “because the ionosphere absorbs it,” said Bandyopadhyay.

“So we want to go somewhere away from [Earth] so that we can get a picture of the Big Bang and evolution of the universe.”  

Telescope size presents challenges

The problem, however, is that in order to capture those wavelengths, not only does this telescope need to be on the moon, it needs to be very large, which makes it hard to build.

There are giant radio telescopes on Earth, which observe shorter radio wavelengths that do penetrate the atmosphere. The 300-metre-wide Arecibo telescope in Puerto Rico — recently demolished in a catastrophic accident — or the 500-metre-wide FAST telescope in China represent significant engineering challenges.

Deployment of the Lunar Crater Radio Telescope would be done by robotic rovers, that would unfold the massive aluminum-mesh antenna. (Saptarshi Bandyopadhyay)

Standalone, self-supporting, dish-shaped radio telescopes can only get to a certain size, based on the strength of the materials they’re made from and the need to resist wind loads. To avoid these issues, the largest radio telescopes are built into natural features in the terrain. Arecibo and FAST, for example, were built in natural, dish-shaped sinkholes. 

Building such a telescope on the moon is, in one sense, easier. The lower gravity on the moon means a larger structure can be built with lighter materials. No atmosphere means no windstorms or other earthly environmental risks, though there are challenges from the moon’s harsh temperatures.  

According to Bandyopadhyay, the moon also has no shortage of appropriately shaped terrain structures in the form of ubiquitous impact craters. 

“These craters seem like natural places to put this dish-shaped telescope because the crater also looks like a bowl.”  

To find a crater candidate, Bandyopadhyay and his team combed over detailed pictures taken by NASA’s Lunar Reconnaissance Orbiter and discovered more than 80,000 suitable craters on the far side of the moon.

Origami-inspired transport and construction 

While the location would provide advantages, there are unique and significant challenges to building on the moon, in particular the harsh working conditions and the difficulty of transporting materials.  

The team studied a range of scenarios for how a telescope might be constructed and transported to the moon. The one they have arrived at is inspired by Japanese paper folding, said Bandyopadhyay.

“Origami is the art of folding paper into smaller and more interesting designs. But in space, origami is extensively used to take these large structures, like a large dish of one kilometre, and we can literally fold it multiple times and make it into a pretty small structure.”

The Lunar Crater Radio Telescope would be sensitive to frequencies that are blocked by Earth’s ionosphere, and would also be shielded from radio noise from Earth broadcasts. (Saptarshi Bandyopadhyay)

The antenna would be built on Earth in the form of a large, but extremely lightweight net-like structure made of conductive aluminum wire. It would be carefully folded into a package that would fit inside the nose cone of a large rocket, possibly the Space Launch System that NASA is currently developing.

Once launched, the antenna would be carried to the moon and land on the floor of the crater into which it would be installed. Then it would need to be deployed.  

“We will have these robots that will go down … to the lander and then pull lift wires that will connect to the lander sitting at the crater floor,” Bandyopadhyay said.

These lift wires would be anchored on the crater rim and as they are winched up, the antenna would unfold and deploy. Ultimately the net-like antenna would be suspended over the crater floor, looking a little like a dish-shaped spider web.  

The tension in the wires would be adjusted to result in the appropriate dish shape to receive radio signals from space and reflect them to a receiver.

All of this technology (the launch rocket possibly excepted) is available today, said Bandyopadhyay.  

The robots, for example, are currently being tested at NASA’s Jet Propulsion Laboratory.  

“These robots are called DuAxel, and they are actively being built at JPL for over a decade now. And these robots have the speciality that they can go down almost steep terrain like just cliff faces.”

[embedded content]

For now, this is an early stage engineering feasibility study, rather than a fully developed mission proposal, but Bandyopadhyay suggests it would certainly be expensive and would be a very high-profile endeavour for NASA.  

“Cost is a big uncertainty right now. Right now, all I can say is we think this will be a flagship-class mission.”

Given that, it’s likely decades away, at least. 

“Space is hard,” said Bandyopadhyay. “I would be surprised if I could see this launched and deployed before I retired, and I’m a young scientist.”

Written and produced by Jim Lebans

Let’s block ads! (Why?)

728x90x4

Source link

Continue Reading

News

The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

Published

 on

 

TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

Source link

Continue Reading

News

B.C. sets up a panel on bear deaths, will review conservation officer training

Published

 on

 

VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

The Canadian Press. All rights reserved.

Source link

Continue Reading

Science

Asteroid Apophis will visit Earth in 2029, and this European satellite will be along for the ride

Published

 on

Asteroid Apophis

The European Space Agency is fast-tracking a new mission called Ramses, which will fly to near-Earth asteroid 99942 Apophis and join the space rock in 2029 when it comes very close to our planet — closer even than the region where geosynchronous satellites sit.

Ramses is short for Rapid Apophis Mission for Space Safety and, as its name suggests, is the next phase in humanity’s efforts to learn more about near-Earth asteroids (NEOs) and how we might deflect them should one ever be discovered on a collision course with planet Earth.

In order to launch in time to rendezvous with Apophis in February 2029, scientists at the European Space Agency have been given permission to start planning Ramses even before the multinational space agency officially adopts the mission. The sanctioning and appropriation of funding for the Ramses mission will hopefully take place at ESA’s Ministerial Council meeting (involving representatives from each of ESA’s member states) in November of 2025. To arrive at Apophis in February 2029, launch would have to take place in April 2028, the agency says.

This is a big deal because large asteroids don’t come this close to Earth very often. It is thus scientifically precious that, on April 13, 2029, Apophis will pass within 19,794 miles (31,860 kilometers) of Earth. For comparison, geosynchronous orbit is 22,236 miles (35,786 km) above Earth’s surface. Such close fly-bys by asteroids hundreds of meters across (Apophis is about 1,230 feet, or 375 meters, across) only occur on average once every 5,000 to 10,000 years. Miss this one, and we’ve got a long time to wait for the next.

When Apophis was discovered in 2004, it was for a short time the most dangerous asteroid known, being classified as having the potential to impact with Earth possibly in 2029, 2036, or 2068. Should an asteroid of its size strike Earth, it could gouge out a crater several kilometers across and devastate a country with shock waves, flash heating and earth tremors. If it crashed down in the ocean, it could send a towering tsunami to devastate coastlines in multiple countries.

Over time, as our knowledge of Apophis’ orbit became more refined, however, the risk of impact  greatly went down. Radar observations of the asteroid in March of 2021 reduced the uncertainty in Apophis’ orbit from hundreds of kilometers to just a few kilometers, finally removing any lingering worries about an impact — at least for the next 100 years. (Beyond 100 years, asteroid orbits can become too unpredictable to plot with any accuracy, but there’s currently no suggestion that an impact will occur after 100 years.) So, Earth is expected to be perfectly safe in 2029 when Apophis comes through. Still, scientists want to see how Apophis responds by coming so close to Earth and entering our planet’s gravitational field.

“There is still so much we have yet to learn about asteroids but, until now, we have had to travel deep into the solar system to study them and perform experiments ourselves to interact with their surface,” said Patrick Michel, who is the Director of Research at CNRS at Observatoire de la Côte d’Azur in Nice, France, in a statement. “Nature is bringing one to us and conducting the experiment itself. All we need to do is watch as Apophis is stretched and squeezed by strong tidal forces that may trigger landslides and other disturbances and reveal new material from beneath the surface.”

The Goldstone radar’s imagery of asteroid 99942 Apophis as it made its closest approach to Earth, in March 2021. (Image credit: NASA/JPL–Caltech/NSF/AUI/GBO)

By arriving at Apophis before the asteroid’s close encounter with Earth, and sticking with it throughout the flyby and beyond, Ramses will be in prime position to conduct before-and-after surveys to see how Apophis reacts to Earth. By looking for disturbances Earth’s gravitational tidal forces trigger on the asteroid’s surface, Ramses will be able to learn about Apophis’ internal structure, density, porosity and composition, all of which are characteristics that we would need to first understand before considering how best to deflect a similar asteroid were one ever found to be on a collision course with our world.

Besides assisting in protecting Earth, learning about Apophis will give scientists further insights into how similar asteroids formed in the early solar system, and, in the process, how  planets (including Earth) formed out of the same material.

One way we already know Earth will affect Apophis is by changing its orbit. Currently, Apophis is categorized as an Aten-type asteroid, which is what we call the class of near-Earth objects that have a shorter orbit around the sun than Earth does. Apophis currently gets as far as 0.92 astronomical units (137.6 million km, or 85.5 million miles) from the sun. However, our planet will give Apophis a gravitational nudge that will enlarge its orbit to 1.1 astronomical units (164.6 million km, or 102 million miles), such that its orbital period becomes longer than Earth’s.

It will then be classed as an Apollo-type asteroid.

Ramses won’t be alone in tracking Apophis. NASA has repurposed their OSIRIS-REx mission, which returned a sample from another near-Earth asteroid, 101955 Bennu, in 2023. However, the spacecraft, renamed OSIRIS-APEX (Apophis Explorer), won’t arrive at the asteroid until April 23, 2029, ten days after the close encounter with Earth. OSIRIS-APEX will initially perform a flyby of Apophis at a distance of about 2,500 miles (4,000 km) from the object, then return in June that year to settle into orbit around Apophis for an 18-month mission.

Related Stories:

Furthermore, the European Space Agency still plans on launching its Hera spacecraft in October 2024 to follow-up on the DART mission to the double asteroid Didymos and Dimorphos. DART impacted the latter in a test of kinetic impactor capabilities for potentially changing a hazardous asteroid’s orbit around our planet. Hera will survey the binary asteroid system and observe the crater made by DART’s sacrifice to gain a better understanding of Dimorphos’ structure and composition post-impact, so that we can place the results in context.

The more near-Earth asteroids like Dimorphos and Apophis that we study, the greater that context becomes. Perhaps, one day, the understanding that we have gained from these missions will indeed save our planet.

 

728x90x4

Source link

Continue Reading

Trending