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Musk says Starship may be ready for orbital launch next month, but FAA review continues – Spaceflight Now – Spaceflight Now

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Elon Musk, the billionaire founder of SpaceX, said Friday the company’s huge new Starship rocket could be ready for its first orbital test launch from South Texas as soon as November, but the schedule comes with two big uncertainties that may push the launch to next year.

“If all goes well, Starship will be ready for its first orbital launch attempt next month, pending regulatory approval,” Musk tweeted.

The new schedule update from Musk came the day after SpaceX test-fired the newest Starship vehicle, known as Ship 20 or SN20, at the company’s development facility near Boca Chica Beach east of Brownsville, Texas. A vacuum-rated Raptor engine, similar to the engines Starship will use in space, ignited for several seconds on a launching stand at SpaceX’s Starbase complex Thursday night.

SpaceX briefly fired the privately-developed rocket again later the same night.

It was the first test-firing of a Raptor vacuum engine mounted to a Starship rocket. The vacuum variant of the methane-fueled Raptor engine has a larger nozzle to improved performance in the airless environment of space.

Three vacuum-rated Raptor engines will fly on orbital-class Starship missions. Three sea level Raptor variants, with smaller nozzles, will be used for vertical Starship landings after returning from space.

Unlike the Starship prototypes flown on the recent atmospheric hops, Ship 20 is covered in thousands of heat-resistant tiles to protect the craft’s stainless steel structure from the scorching heat it will encounter during re-entry into Earth’s atmosphere.

The Starship will launch on top of a huge reusable first stage booster called the Super Heavy. Made of stainless steel, the entire stack stands 394 feet (120 meters) tall, higher than any rocket ever built.

Fitted with up to 33 Raptor engines, the Super Heavy will propel the Starship into space with twice the thrust of NASA’s Apollo-era Saturn 5 moon rocket, and nearly double the power of NASA’s Space Launch System heavy-lift rocket.

In August, SpaceX teams in South Texas briefly stacked the entire Starship rocket on a launch mount for a fit check and photo opportunity. At the time, SpaceX connected 29 Raptor engines — four fewer than the booster will use on an operational flight — to the Super Heavy and rolled the booster to the ever-expanding launch complex, just east of the company’s build site.

After the fit check, SpaceX removed the Raptor engines from the Super Heavy, designated Booster 4, as attention turned to preparing Ship 20 for cryogenic proof testing in September.

SpaceX then readied Starship for its first static fire tests this week. More test-firings may occur before Ship 20 is mounted on top of the Super Heavy booster again.

Meanwhile, SpaceX plans to perform cryogenic proof testing of Booster 4 some time in the coming weeks, likely followed by a series of test-firings, culminating in a static fire with its full complement of Raptor engines.

Outfitting of the launch pad tower at Boca Chica has also continued since its initial construction over the summer. Earlier this week, crews lifted massive arms, nicknamed “chopsticks,” onto the launch tower that SpaceX aims to use for catching descending Super Heavy boosters.

Although SpaceX has moved forward with great speed at Boca Chica, the chances of the Super Heavy and Starship vehicles being ready for flight next month are uncertain. Musk often sets aspirational schedule goals, and in September 2019 said he wanted to attempt the first orbital launch attempt with Starship within six months.

Another schedule hurdle might be the Federal Aviation Administration, which is reviewing the environmental impacts of SpaceX’s operations in South Texas. The FAA issued a draft environmental report last month after consultation with several federal and state agencies.

The draft report marks a re-evaluation of the FAA’s original environmental impact statement before SpaceX started construction of the Boca Chica site in 2014. At that time, SpaceX planned to launch Falcon 9 and Falcon Heavy rockets from South Texas, but the scope of the project has since changed to focus on development of Starship and Super Heavy.

The FAA held public hearings Monday and Wednesday, and some 120 people voiced their opinions on the project’s environmental impacts. The public comments were more than two-to-one in favor of the FAA finalizing the draft programmatic environment assessment, and issuing SpaceX a launch license for the Starship orbital test flight.

Many of the comments in favor of SpaceX came from members of the public outside Texas. The share of people who identified themselves as local residents and voiced opposition was higher.

Joyce Hamilton, who said she was a member of the local community, worried that SpaceX would damage the “fragile and unique coastline” at Boca Chica Beach.

“In fact, we’ve already seen the damaging impact of a recent launch failure with a wide and destructive debris field along the beach and surrounding wetlands,” Hamilton said. “I’d like to just end by urging the FAA to conduct a serious comprehensive environmental impact study.”

Rebecca Hinojosa, a Brownsville resident, said SpaceX has been a destructive influence on the community through gentrification, and displaced residents who once lived near the Boca Chica site. SpaceX bought out homes in the area as it constructed the facility.

Others were supportive of the FAA allowing SpaceX to go ahead with no delay, citing the positive economic effects of SpaceX’s presence in the Rio Grande Valley.

“Elon Musk chose our community to be the next home of his SpaceX operation, and very, very quickly after setting up, this area went from being one of the poorest areas, one of the most looked-down, in the entire nation … We’re no longer in that position. We’re now one of the most sought after zip codes to live and raise your children,” said Jessica Tetreau, a Brownsville city commissioner.

“I don’t just ask you,” she concluded. “I beg you to give them that permit.”

“As far as the environment goes, it seems to me that SpaceX has a good plan in place to mitigate the vast majority of environmental effects from the build and test sites,” said Michael O’Halloran, who did not identify himself as a local resident. “Starship and Super Heavy are clearly worth the gamble.”

Crews at SpaceX’s Starbase test site in South Texas stack the company’s first full-scale Starship launch vehicle for a fit check in August. Credit: SpaceX

The FAA is accepting written comments until Nov. 1, then will determine whether to finalize the draft environmental assessment or begin a new environmental impact statement if the environmental effects would be significant and could not be properly mitigated.

A new environmental impact statement would take months, or even years, to complete.

A decision by the FAA on which route to take is not expected immediately. The FAA said it is reviewing the environmental impacts from SpaceX’s Starship launch and re-entry operations, debris recovery, the launch pad integration tower and other launch-related construction, and local road closures at Boca Chica.

SpaceX can’t launch the Starship and Super Heavy vehicle until the FAA issues a license, which will only come after the completion of the environmental process.

NASA awarded SpaceX a contract to develop a version of the Starship rocket as a human-rated lander for the agency’s Artemis moon missions.

That contract award is currently on hold after Blue Origin, the space company founded by billionaire Jeff Bezos, filed suit in the U.S. Court of Federal Claims. A ruling on the lawsuit could come next month.

SpaceX is developing the privately-owned Starship vehicle as a fully reusable launch and space transportation system capable of ferrying more than 100 metric tons of cargo into low Earth orbit, more than any other rocket in the world. SpaceX eventually aims to develop an in-space refueling capability to extend Starship’s heavy-duty cargo carrying range into the solar system.

During an orbital launch attempt, a reusable Super Heavy first stage booster will detach from the Starship and come back to Earth for a vertical landing. For the first orbital mission, SpaceX plans to guide the the booster to a water landing in the Gulf of Mexico.

SpaceX is also modifying offshore oil drilling rigs to serve as floating Starship launch and landing platforms.

The Starship will continue into orbit and deploy its payloads or travel to its deep space destination, and finally return to Earth to be flown again. The Starship vehicle doubles as an upper stage and a refillable transporter to ferry people and cargo through space to destinations in Earth orbit, the moon, Mars, and other distant locations.

The reusable architecture, which builds upon SpaceX’s partially reusable Falcon 9 rocket, is designed to reduce the cost of each flight.

The Starship’s first orbital test flight, though audacious in scale, will aim to prove out the rocket’s basic launch and re-entry capabilities without fully testing out the complicated landing and recovery systems, according to a SpaceX’s filing with the Federal Communications Commission earlier this year.

On the first orbital mission, SpaceX plans for the Starship to re-enter the atmosphere after one trip around Earth, heading for a controlled landing at sea in the Pacific Ocean near Hawaii.

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Follow Stephen Clark on Twitter: @StephenClark1.

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Sechelt Skies: Sun, Earth and moon align for awesome tides – Coast Reporter

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There will be some interesting lunar action this December as Venus makes a close approach.

The new moon will occur very early on Dec. 4 and will pass below Venus, less than three degrees away, then by Saturn and Jupiter successively Dec. 7 through Dec. 9. The close pass by Venus will be neat for anyone with a decent telescope – you’ll be able to see the moon as a thin crescent and a remarkably similar-looking thin crescent of Venus about one fiftieth the size of the moon.

By about Christmas Day, Venus will appear lower in the southwest just after sunset as it heads west to pass between us and the sun (inferior conjunction) on Jan. 8. Mercury will join Venus over the next two weeks as Mercury moves east and out from behind the sun.  Their closest approach will be about three degrees on Dec. 28. By Jan. 8, Venus will be only 0.266 astronomical units (the Earth-sun mean distance) from Earth and just more than one minute of arc in apparent diameter – one thirtieth the size of the moon. This is discernible even with a pair of 7 x 30 binoculars as a reasonably large but very thin crescent. The convenient part is that, since Venus’ orbit is tipped to our own, it will pass about five degrees north of the sun and will be visible for a week or two both in the evening in the southwest and the morning in the southeast.

Something we’re all looking forward to: the winter solstice occurs at 0859 on Dec. 21 and the days begin to get longer.

One other neat thing about this month is that the new moon and lunar perigee – closest approach to Earth – occur only three hours apart on Dec. 4. As well, Earth’s perihelion – closest approach to the sun – occurs on Jan. 3. This means that on Dec. 4, the moon is just about as close as it gets to the Earth and the Earth is nearly as close as it gets to the sun. Since all three are in a nearly straight line all of the tidal effects add up. When two objects orbit each other gravitationally, they each have a gravitational field that decreases as the square of the distance away from each. That means that each body sees a slightly stronger pull of gravity on the side facing the other body and slightly weaker on the side opposite. Since Earth has liquid oceans, they will bulge slightly toward the moon when it’s overhead; on the side farthest away, they see a slightly lower pull from the moon so they bulge away from the moon.

As the TV advertisers say: “But, wait, there’s more!” The oceans also respond to the sun’s gravitational field in the same way. As far as I can figure out (and I’m hitting the limits on my long, long ago math degree), the tidal forces vary as the mass of the attracting body divided by the cube of its distance. If you look up all the mean values for the sun and the moon, you get values of 594 for the sun and 1,288 for the moon. Units are metric tons per cubic kilometre, whatever that actually means. Anyway, the ratio means that the sun exerts a tidal force on the Earth of about 46 per cent of that of the moon. For the Dec. 4 new moon, however, the tidal forces rise to 621 and 1,618 for sun and moon, respectively; this is a total of about 19 per cent greater tidal forces than average. The remaining complication is that the tidal bulges are at their peaks in the plane of Earth’s orbit; in our winter they’re near the Tropic of Capricorn sunward and the Tropic of Cancer away from the sun. That means we’ll see a big variation from day (lower) to night (higher). We seem to see the greatest range about two to three days after the new and full moon for reasons I don’t understand. But, I’d say we can expect some awesome tides the night of Dec. 6. We’ll see pretty much the same in early January too; a little more from the sun and a bit less from the moon.

The remaining complication is that the shape of our coastlines and ocean depths can hugely affect tides. Best examples: Bay of Fundy and Cook Inlet in Alaska (leads to Anchorage). In both cases, the shape and depths of each leads to a resonance period just about the same as the lunar tidal period so the water sloshes in and out like a kid on a swing in time with the moon’s pull. The whole subject is the sort of thing that highly nerdy careers are made of.

Bruce Fryer’s presentation on this and other subjects can be watched on YouTube by entering Sunshine Coast Astronomy in the search line. I found it excellent and will recommend any of the stuff on the channel. The next online Sunshine Coast Astronomy Club meeting is Dec. 10 at 7 p.m. Signup information will be available at sunshinecoastastronomy.wordpress.com.

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Could we really deflect an asteroid heading for Earth? An expert explains NASA's latest DART mission – Phys.Org

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Small asteroid impacts showing day-time impacts (in yellow) and night-time impacts (in blue). The size of each dot is proportional to the optical radiated energy of the impact. Credit: NASA JPL

A NASA spacecraft the size of a golf cart has been directed to smash into an asteroid, with the intention of knocking it slightly off course. The test aims to demonstrate our technological readiness in case an actual asteroid threat is detected in the future.

The Double Asteroid Redirection Test (DART) lifted off aboard a SpaceX rocket from California on November 23, and will arrive at the target asteroid system in September, next year.

The mission will travel to the asteroid Didymos, a member of the Amor group of asteroids. Every 12 hours Didymos is orbited by a mini-moon, or “moonlet”, Dimorphos. This smaller half of the pair will be DART’s target.

Are we facing an extinction threat from asteroids?

We’ve all seen disaster movies in which an asteroid hits Earth, creating an similar to the one that killed off the dinosaurs millions of years ago. Could that happen now?

Well, Earth is actually bombarded frequently by small asteroids, ranging from 1-20 metres in diameter. Almost all asteroids of this size disintegrate in the atmosphere and are usually harmless.

There is an inverse relationship between the size of these object and the frequency of impact events. This means we get hit much more frequently by small objects than larger ones—simply because there are many more smaller objects in space.

Asteroids with a 1km diameter strike Earth every 500,000 years, on average. The most “recent” impact of this size is thought to have formed the Tenoumer impact crater in Mauritania, 20,000 years ago. Asteroids with an approximate 5km diameter impact Earth about once every 20 million years.

The 2013 Chelyabinsk meteoroid, which damaged buildings in six Russian cities and injured around 1,500 people, was estimated to be about 20m in diameter.

This animation shows DART’s trajectory around the Sun. Pink = DART | Green = Didymos | Blue = Earth | Turquoise = 2001 CB21 | Gold = 3361 Orpheus.

Assessing the risk

NASA’s DART mission has been sparked by the threat and fear of a major asteroid hitting Earth in the future.

The Torino scale is a method for categorising the impact hazard associated with a near-Earth object (NEO). It uses a scale from 0 to 10, wherein 0 means there is negligibly small chance of collision, and 10 means imminent collision, with the impacting object being large enough to precipitate a global disaster.

The Chicxulub impact (which is attributed to the extinction of non-avian dinosaurs) was a Torino scale 10. The impacts that created the Barringer Crater, and the 1908 Tunguska event, both correspond to Torino Scale 8.

With the increase of online news and individuals’ ability to film events, asteroid “near-misses” tend to generate fear in the public. Currently, NASA is keeping a close eye on asteroid Bennu, which is the object with the largest “cumulative hazard rating” right now. (You can keep up to date too).

With a 500m diameter, Bennu is capable of creating a 5km crater on Earth. However, NASA has also said there is a 99.943% chance the asteroid will miss us.

Brace for impact

At one point in their orbit around the Sun, Didymos and Dimorphos come within about 5.9 million km of Earth. This is still further away than our Moon, but it’s very close in astronomical terms, so this is when DART will hit Dimorphos.

Could we really deflect an asteroid heading for Earth? An expert explains NASA's latest DART mission
The DART mission dates and timeline events. Credit: Johns Hopkins University

DART will spend about ten months travelling towards Didymos and, when it’s close by, will change direction slightly to crash into Dimorphos at a speed of about 6.6km per second.

The larger Didymos is 780m in diameter and thus makes a better target for DART to aim for. Once DART has detected the much smaller Dimorphos, just 160m in diameter, it can make a last-minute course correction to collide with the moonlet.

The mass of Dimorphos is 4.8 million tonnes and the mass of DART at impact will be about 550kg. Travelling at 6.6km/s, DART will be able to transfer a huge amount of momentum to Dimorphos, to the point where it’s expected to actually change the moonlet’s orbit around Didymos.

This change, to the tune of about 1%, will be detected by ground telescopes within weeks or months. While this may not seem like a lot, 1% is actually a promising shift. If DART were to slam into a lone asteroid, its orbital period around the Sun would change by only about 0.000006%, which would take many years to measure.

So we’ll be able to detect the 1% change from Earth, and meanwhile the pair will continue along its orbit around the Sun. DART will also deploy a small satellite ten days before impact to capture everything.

This is NASA’s first mission dedicated to demonstrating a planetary defence technique. At a cost of US$330 million, it’s relatively cheap in space mission terms. The James Webb Telescope set to launch next month, costs close to US$10 billion.

There will be little to no debris from DART’s impact. We can think of it in terms of a comparable event on Earth; imagine a train parked on the tracks but with no brakes on. Another train comes along and collides with it.

The trains won’t break apart, or destroy one another, but will move off together. The stationary one will gain some speed, and the one impacting it will lose some speed. The trains combine to become a new system with different speeds than before.

So we won’t experience any impact, ripples or debris from the DART mission.

Could we really deflect an asteroid heading for Earth? An expert explains NASA's latest DART mission
Typical asteroid orbits remain between Mars and Jupiter, but some with elliptical orbits can pass close to Earth. Credit: Pearson

Is the effort really worth it?

Results from the mission will tell us just how much mass and speed is needed to hit an asteroid that may pose a threat in the future. We already track the vast majority of asteroids that come close to Earth, so we would have early warning of any such object.

That said, we have missed objects in the past. In October 2021, Asteroid UA_1 passed about 3,047km from Earth’s surface, over Antarctica. We missed it because it approached from the direction of the Sun. At just 1m in size it wouldn’t have caused much damage, but we should have seen it coming.

Building a deflection system for a potential major asteroid threat would be difficult. We would have to act quickly and hit the target with very good aim.

One candidate for such a system could be the new technology developed by the US spaceflight company SpinLaunch, which has designed technology to launch satellites into orbit at rapid speeds. This device could also be used to fire masses at close-passing asteroids.


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Double Asteroid Redirection Test launch could be key step forward in planetary defense


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'Unsettling': New Study Reveals Arctic Ocean Warming for Over a Century – Common Dreams

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New research published Wednesday revealed the Arctic Ocean has been warming for decades longer than scientists previously understood, raising fresh concerns as the polar region faces the growing threat of a total loss of the seasonal ice that is crucial to the survival of the imperiled marine ecosystem.

“We’re talking about the early 1900s, and by then we’ve already been supercharging the atmosphere with carbon dioxide.”

A study published in Science Advances found that “the recent expansion of Atlantic waters into the Arctic Ocean”—a phenomenon knows as “Atlantification”—offers “undisputable evidence of the rapid changes occurring in this region.”

“We reconstruct the history of Atlantification along the eastern Fram Strait during the past 800 years using precisely dated paleoceanographic records,” the study’s authors wrote, referring the the maritime passage between Greenland and Svalbard. “Our results show rapid changes in water mass properties that commenced in the early 20th century—several decades before the documented Atlantification by instrumental records.”

Study co-author Tessi Tommaso of the Institute of Polar Sciences at the National Research Council in Bologna, Italy, said in a statement that “when we looked at the whole 800-year timescale, our temperature and salinity records look pretty constant. But all of a sudden at the start of the 20th century, you get this marked change in temperature and salinity—it really sticks out.”

Francesco Muschitiello—one of the study’s authors and a Cambridge University geographer—told CNN that “the Arctic Ocean has been warming up for much longer than we previously thought. And this is something that’s a bit unsettling for many reasons, especially because the climate models that we use to cast projections of future climate change do not really simulate these type of changes.”

“We’re talking about the early 1900s, and by then we’ve already been supercharging the atmosphere with carbon dioxide,” he continued. “It is possible that the Arctic Ocean is more sensitive to greenhouse gases than previously thought. This will require more research, of course, because we don’t have a solid grip on the actual mechanisms behind this early Atlantification.”

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In September, Common Dreams reported that Arctic sea ice shrank to its second-smallest extent since record-keeping began more than four decades ago.

The new study also follows research published September in the journal Earth’s Future showing that the Last Ice Area—which is north of Canada and Greenland and is where the remaining summer sea ice will persist the longest as the climate emergency progresses—could disappear completely by 2100.

“Unfortunately, this is a massive experiment we’re doing,” study co-author Robert Newton, a climate researcher at Columbia University and co-author of the Last Ice Area study, said in a statement. “If the year-round ice goes away, entire ice-dependent ecosystems will collapse, and something new will begin.”

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