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Join Amateur Astronomer Frank Hitchens for Science Literacy, Space Week Celebrations – Kingston Herald

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Both Science Literacy Week, a celebration of Canadian science in Canadian culture, and World Space Week are coming soon. What better way to celebrate than by learning from a Canadian amateur astronomer? Frank Hitchens, who hails from Perth, Ont., is the star of two upcoming KFPL events centred on the cosmos.

On Sept. 24, during Science Literacy Week, Hitchens will host Eye in the Sky: The Hubble Space Telescope, a discussion about the telescope from its launch in 1990 to its retirement in 2011. Hubble was one of the most productive tools for gathering information from beyond our planet. Canada has a storied history with Hubble, contributing the Canadarm, which helped maintain and repair the telescope during its two decades of operation.

The event takes place from 2-3 p.m.at the Isabel Turner Branch. Register online.

Hitchens will return to the Isabel Turner Branch during World Space Week for Voyager: Quest for the Titans, Oct. 5 from 6:30-7:30 p.m. Learn about Voyager I, the space probe that is the most distant manufactured object from Earth, over 23 billion kilometres away. Voyager, launched in 1977, collected valuable information on Saturn, its moon Titan, and Jupiter and continues communicating with Earth.

Register online

“It will be great having Frank back at KFPL to discuss Hubble and Voyager,” said Jake Miller, Librarian, Adult Programming. “So much of what we learned during the past four decades is because of these magnificent instruments. These sessions will be a great entry point for those picking up astronomy. Spaces are already filling up!”


Release | image: Kingston Frontenac Public Library

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Squirrels, volcanoes, and ancient DNA – TownAndCountryToday.com – Town and Country TODAY

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ATHABASCA — What does the research into ground squirrels dating back 50,000 years have to do with ancient DNA or volcanoes? 

Those are some of the fascinating details Scott Cocker, a paleoecologist and PhD student at the University of Alberta (U of A), will be discussing in a Zoom presentation hosted by Science Outreach – Athabasca Sept. 27 at 7 p.m. 

“I’m interested in the ground squirrels themselves because we jokingly refer to them as furry botanists,” Cocker said in a Sept. 15 interview. “They were grabbing plants; they were grabbing whatever they could grab before they went into hibernation. So, they would store all this stuff in their nest and then the nest is what we find 40,000 years later or whatever have you … frozen in the permafrost with all those seeds or with bones of other animals. They are basically like little archives of the Ice Age and Yukon.” 

Cocker realized while everyone was distracted by larger creatures like woolly mammoths and woolly rhinos, they didn’t offer as much information on life at the time as ground squirrel nests could. 

“The ecosystem and the environment, we call that the mammoth steppe and for a long time that’s what everyone referred to; the mammoth steppe this, the mammoth steppe that, and it’s just because the mammoths are big and charismatic,” he said. “But my whole thesis is that if you really want to understand the mammoth steppe and the environment that they were living in, you actually have to look to things like the ground squirrels because they tell us way more about the environment than the mammoths do.” 

Throw in some new sequencing of DNA which allows scientists to accurately identify a species from just small pieces of DNA. 

“In the last 20 years, it’s something that’s been developed,” he said. “We can work with modern DNA really easily because stranded DNA are in the count of millions … but once that organism dies and sits around for a while, then the DNA starts to degrade, and it breaks down over time and so we end up with these really short little pieces of DNA.” 

Then mix in the aftermath of a volcanic eruption in southern Alaska 25,000 years ago which covered the area with up to a metre of ash and it changes how all fauna lived and you have the basics of Cocker’s presentation. 

“How did that impact the animals and plants at the time of the eruption? Because it definitely was one of the largest in the last million years in this part of the world,” Cocker said. “It completely covered the plants. Think about (the) ground squirrels or the voles and mice and stuff that … rely on foraging and you’re half the size of the ash fall, you’re gonna struggle.” 

The link to the presentation can be found on the Science Outreach – Athabasca website and social media and will start at 7 p.m. Sept. 27. 

hstocking@athabasca.greatwest.ca 

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Why is NASA crashing a spacecraft into a harmless asteroid at 14,000mph? – Sky News

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A harmless asteroid millions of miles away is about to be rammed by a NASA spacecraft at 14,000mph. Why? The fate of the human race could one day depend on doing the same.

It has been 66 million years since an asteroid crashing into the Earth brought an end to the reign of the dinosaurs, scientists say, and they are keen to avoid a similar ending for humanity.

Sky News takes a look at NASA’s latest experiment – a $325m (£301m) planetary defence test – and answers some key questions about how it could prove useful down the line.

What is the Dart spacecraft?

Dart – a snappier nickname than Double Asteroid Redirection Test – is essentially a battering ram the size of a small vending machine.

It faces certain destruction in the fulfilment of its goal.

Dart weighs 570kg and has a single instrument: a camera used for navigating, targeting and chronicling its final demise.

More on Nasa

Where is the spacecraft going?

Dart is headed for a pair of asteroids about seven million miles from Earth. Its target is called Dimorphos, which is the smaller offspring of Didymos (that’s Greek for twin).

Dimorphos is roughly 525 feet (160 metres) across and it orbits the much larger Didymos at a distance of less than a mile (1.2km).

NASA insists there’s a zero chance either asteroid will threaten Earth – now or in the future. That’s why the pair was picked.

The spacecraft’s navigation is designed to distinguish between the two asteroids and, in the final 50 minutes, target the smaller one.

What happens on impact?

“This really is about asteroid deflection, not disruption,” said Nancy Chabot, a planetary scientist and mission team leader at Johns Hopkins University, which is managing the effort.

“This isn’t going to blow up the asteroid. It isn’t going to put it into lots of pieces.”

Instead, the impact will dig out a crater metres in size and hurl some two million pounds of rocks and dirt into space.

Why are scientists doing this?

The impact should be just enough to nudge the asteroid into a slightly tighter orbit around its companion space rock – demonstrating that if a killer asteroid ever heads our way, we’d stand a fighting chance of diverting it.

Cameras and telescopes will watch the crash, but it will take months to find out if it actually changed the orbit.

Observatories will track the pair of asteroids as they circle the sun, to see if Dart altered Dimorphos’ orbit.

In 2024, a European spacecraft named Hera will retrace Dart’s journey to measure the impact results.

Although the intended nudge should change the moonlet’s position only slightly, that will add up to a major shift over time, according to Ms Chabot.

“So if you were going to do this for planetary defence, you would do it five, 10, 15, 20 years in advance in order for this technique to work,” she said.

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Last West Coast Delta IV Heavy to launch with NROL-91 – NASASpaceFlight.com – NASASpaceflight.com

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United Launch Alliance’s (ULA) Delta IV Heavy rocket made its last West Coast launch on Saturday, carrying out a mission for the National Reconnaissance Office, as it moves one flight closer to retirement. Liftoff of the NRO Launch 91 (NROL-91) mission from Space Launch Complex 6 — at the Vandenberg Space Force Base in California — took place at 3:25 PM PDT (22:25 UTC).

Delta IV Heavy is the most powerful version of the Delta IV, one of two rockets developed under the US Air Force’s Evolved Expendable Launch Vehicle (EELV) program to meet the US Government’s launch needs in the early 21st century. Delta IV, alongside its former competitor-turned-stablemate Atlas V, is now being phased out as a new generation of launchers prepare to take their place.

One of the first steps in that transition was winding down Delta IV operations, with the last Delta IV Medium+ launch taking place in 2019. Delta IV Heavy, with its significantly higher payload capacity, has been kept in service to carry out a handful of national security launches that cannot be performed by Atlas V.

Saturday’s mission, NROL-91, is the final Delta IV launch from California’s Vandenberg Space Force Base, with the rocket’s remaining missions to be executed from the East Coast at Cape Canaveral.

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While the National Reconnaissance Office (NRO) keeps details of its satellites classified, the use of a Delta IV Heavy and the fact the launch is taking place from Vandenberg speak volumes. Delta IV Heavy missions carry satellites that have too great a mass for the most powerful Atlas V configurations to place into their destined orbits, indicating the satellite is very heavy, bound for a high orbit, or both. From its location on the West Coast, Vandenberg is an ideal launch site for low Earth orbit (LEO) reconnaissance satellites operating in polar and near-polar orbits, as well as some signals intelligence satellites in elliptical orbits.

Those signals intelligence satellites are typically launched by smaller rockets, so the combination of rocket and launch site suggests that NROL-91 will deploy one of the agency’s large imaging satellites, part of a program identified in previously leaked documents as Crystal. The NRO does not acknowledge the names or types of satellites it operates; instead, they are assigned an NROL designation prior to launch and a numerical USA designation upon reaching orbit. The satellite launched by the NROL-91 mission is expected to take on the designation USA-337, the next available number in this sequence.

Crystal, also known as KH-11, is the successor to a long line of Keyhole reconnaissance satellites that the NRO has operated since the 1960s. Earlier members of this series used small capsules to return photographic film to Earth for development. When it was introduced in 1976, the KH-11 did away with these, instead downlinking images electronically. Since then, the satellites have undergone further upgrades, with several different blocks of spacecraft identified.

NROL-91 will be the nineteenth Crystal satellite to be launched, and the fifth to fly aboard a Delta IV. Previous satellites had flown aboard Titan rockets, initially the Titan III(23)D and Titan III(34)D, and later the Titan IV. The fourteenth KH-11, USA-186, was the payload for the final Titan IV launch and was at the time also expected to be the last Crystal satellite. Failures in the procurement of the successor Future Imagery Architecture (FIA) saw additional Crystal spacecraft constructed, with the first bearing a conspicuous phoenix on its mission patch.

Declassified image taken by a KH-11 satellite, showing Iran’s Semnan launch site (Credit: NRO/US Government)

The Crystal satellites are believed to give the NRO its highest-resolution pictures of the Earth’s surface. They are rumored to resemble the Hubble Space Telescope but pointed toward the Earth, rather than out into space. Most have operated in a Sun-synchronous orbit (SSO) — a particular type of low, near-polar, orbit that allows them to cover most of the Earth’s surface, ensuring they pass over each point at the same local solar time every day, ensuring consistent lighting conditions.

Up until now, the only KH-11 not operated in Sun-synchronous orbit has been USA-290. Deployed by the NROL-71 mission in January 2019, it was the last-but-one KH-11 to launch prior to NROL-91. With an orbital inclination of 73.6 degrees, its orbit is lower than the other operational satellites, meaning that it does not pass as close to the Earth’s poles.

Hazard areas published ahead of the NROL-91 mission, to warn aviators and mariners to stay away from areas where debris from the launch is expected to fall, suggest that this mission is targeting the same inclination as USA-290, rather than the more typical SSO.

With Saturday’s launch marking the last Delta IV flight from Vandenberg, it is not clear whether this also means that NROL-91 was the final launch of a Crystal satellite. The now-abandoned optical element of the FIA program sought to develop a smaller, cheaper high-resolution imaging satellite using more modern technology. Future missions could follow this model, or alternatively, Crystal satellites could continue launching aboard a different rocket — such as Falcon Heavy or ULA’s next-generation vehicle, Vulcan.

Delta IV during rollout from the Horizontal Integration Facility to the launch pad ahead of the NROL-91 mission (Credit: United Launch Alliance)

The Delta IV Heavy is a two-stage expendable launch vehicle, with its first stage consisting of three Common Booster Cores (CBCs). A five-meter-diameter Delta Cryogenic Second Stage (DCSS) sits atop this, with the satellite housed within the payload fairing at the top of the rocket. Both stages of the rocket use cryogenic propellants: liquid hydrogen and liquid oxygen.

First flown in November 2002, Delta IV has made 42 flights prior to the NROL-91 mission, of which 13 have used the Heavy configuration. Other versions of the Delta IV have included the long-retired Delta IV Medium, which consisted of a single CBC, a four-meter DCSS, and several intermediate Medium+ configurations which augmented the Medium’s CBC with two or four solid rocket boosters and could fly with either version of the second stage.

Of the previous 42 missions, Delta IV has completed 41 successfully. Its only failure was the maiden flight of the Delta IV Heavy in 2004, during which all three CBCs shut down prematurely due to cavitation in the propellant lines. The rocket, which was carrying a mass simulator and a pair of small satellites, reached a lower orbit than had been planned.

Each Common Booster Core is powered by an Aerojet Rocketdyne RS-68A engine, capable of providing 312 kilonewtons of thrust at sea level. The upper stage and payload are mounted above the center core, while the others are attached to the port and starboard sides of the vehicle.

While the CBCs provide an initial boost through Earth’s atmosphere, the DCSS is responsible for completing the insertion of the NROL-91 payload into orbit. It is powered by a single cryogenic engine from Aerojet Rocketdyne’s RL10 family.

The NROL-91 payload, encapsulated in its fairing, is installed atop the rocket (Credit: United Launch Alliance)

Although the Delta IV program is being wound down, Saturday’s launch marks the first flight of a new engine variant, the RL10C-2-1, which replaces the RL10B-2 used on previous Delta IV missions. The RL10C was developed to reduce production costs by increasing standardization between the RL10A engines used on Atlas and the RL10Bs used on Delta. The RL10C-2-1 is expected to be used on the remaining Delta IV launches, as well as future Space Launch System (SLS) missions with the Interim Cryogenic Propulsion Stage (ICPS), which is derived from DCSS.

For NROL-91, Delta IV flew with a bisector, or two-part, payload fairing made of composite materials. This is one of two fairings that can be flown on Delta IV Heavy and has been used on previous Crystal launches. Most other national security missions have used a trisector — three-part — design of metallic construction, derived from a fairing previously used on the Titan IV.

Delta IV launches from Vandenberg Space Force Base take place from Space Launch Complex 6 (SLC-6), and with Saturday’s launch marking the last Delta IV mission from Vandenberg, this is expected to be the last time the complex is used in its current configuration. With no launch providers having made public plans to use SLC-6 going forward, the complex will likely be decommissioned and mothballed in the immediate future, closing another chapter in the eventful history of this launch pad.

SLC-6 was originally built in the 1960s but did not see a launch until 1995, after the first two programs that were meant to use it were both canceled at late stages of development. The first of these was the Titan IIIM, an upgraded version of the Titan III rocket that was to have launched the Manned Orbiting Laboratory (MOL), a crewed reconnaissance platform developed by the US Air Force. Construction of the launch complex began in March 1966 and was nearing completion when MOL was abandoned in 1969.

After MOL’s cancellation, SLC-6 was selected as a launch site for Space Shuttle missions to polar orbit. Such orbits could not safely be reached from the Kennedy Space Center, so a launch pad on the West Coast was deemed necessary for planned military Shuttle missions. After the pad had undergone extensive modifications, the orbiter Enterprise was used for fit checks in early 1985, and the complex was accepted into service later that year.

Space Shuttle Enterprise at SLC-6 in February 1985 (Credit: US Air Force)

The loss of Challenger in 1986, and the reviews of the Space Shuttle program that followed, saw plans for polar orbit missions canceled. At the time of the accident, the first launch from SLC-6 had been a few months away, with Discovery slated to deploy an experimental reconnaissance satellite during the STS-62-A mission. With Shuttle launches restricted to the Kennedy Space Center, SLC-6 was again placed into mothballs.

It would not be until the 1990s, when Lockheed selected SLC-6 for its Lockheed Launch Vehicle (LLV) rocket, later named Athena, that SLC-6 would finally host a launch. Four missions, two using the Athena I configuration followed by two using the Athena II configuration, were flown between August 1995 and September 1999. These launches did little to help SLC-6’s cursed reputation: the first and third missions failed to achieve orbit, while the second successfully deployed NASA’s Lewis satellite only for the spacecraft to malfunction and lose power less than three days later.

In a strange twist of fate, NROL-91 lifted off 23 years to the day after the fourth and final Athena launch from SLC-6, which successfully deployed a commercial Ikonos imaging satellite.

Athena was far smaller than the rockets that SLC-6 had been designed to serve, but Boeing’s need to find a West Coast launch site for its Delta IV rocket would bring the pad a new lease of life. The first of 10 Delta IV flights from the pad — including the NROL-91 mission — took place in June 2006 when a Delta IV Medium+(4,2) flew the NROL-22 mission, deploying a signals intelligence satellite.

A Delta IV Medium+(5,2) launches from SLC-6 in 2012 (Credit: United Launch Alliance)

The Delta IV Medium and Medium+(4,2) each made a single flight from SLC-6, while the Medium+(5,2), with a five-meter upper stage, made three flights from the pad. Including Saturday’s launch, the Delta IV Heavy configuration has used the pad five times, with all of its launches deploying Crystal satellites.

Overall, NROL-91 is the fourteenth launch to take place from SLC-6. In keeping with previous Delta IV missions, the rocket has been assigned a flight number, or Delta number, which indicates its place in the history of the Delta series of rockets. These numbers have counted — with a handful of exceptions — up from the first Thor-Delta launch in 1960. While the Delta IV is a completely different rocket even compared to the Delta II that retired a few years ago, the tradition has been maintained, and the rocket that performed Saturday’s launch is be Delta 387.

Saturday’s countdown saw the Delta IV rocket filled with cryogenic propellants while critical systems are powered up and tested as the count proceeds toward liftoff. The ignition sequence for the three RS-68A engines began seven seconds before liftoff with the starboard booster before the port and center cores ignited two seconds later. This staggered start helps mitigate the effects of hydrogen build-up around the base of the vehicle, which has scorched the rocket or set fire to insulation on previous missions.

Liftoff occurred at T0. After Delta IV cleared the tower, it began a series of pitch and yaw maneuvers to attain its planned orbit, with the first of these beginning about 10 seconds after liftoff. Flying downrange, Delta 387 throttled down its center core to its partial thrust setting. It passed through the area of maximum dynamic pressure, or Max-Q, 89.6 seconds into the mission and reached Mach 1, the speed of sound, about 1.4 seconds later.

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With the side boosters firing at full thrust and the center core operating in partial thrust mode, the port and starboard cores depleted their propellant first. As they approached burnout, they began to throttle back before shutting down at the three-minute and 56.3-second mark in the mission. The spent boosters separated 2.2 seconds later, falling away from the center core as it throttled up to full thrust.

Booster Engine Cutoff (BECO), the end of first-stage flight, occurs five minutes and 37 seconds after liftoff. Six and a half seconds after BECO, the first stage separates and the DCSS begins preparations to ignite its RL10C-2-1 engine, including deployment of the extendible nozzle. RL10 ignition occurs under 13 seconds after stage separation. 10 seconds into the burn, Delta IV’s payload fairing separates, and the NROL-91 payload is exposed to space for the first time.

With fairing separation complete, NRO missions tend to enter a news blackout, with further mission details remaining classified other than a brief press release to confirm the successful deployment of the satellite. The DCSS can be expected to continue firing its engine for about 12 minutes as it inserts the satellite directly into orbit. Spacecraft separation will occur shortly afterward, before the DCSS restarts its engine for a deorbit burn.

With Delta 387’s mission complete, only two more Delta IV missions remain to be launched. These are both slated to fly from the Cape Canaveral Space Force Station, with the NROL-68 mission slated for liftoff early next year and NROL-70 to follow in the first months of 2024. The first flight of Vulcan, ULA’s replacement for both its Delta IV and Atlas V rockets, is also currently scheduled for the first half of next year.

While these milestone launches are still some months away, ULA will be back in action on Friday with an Atlas V slated to deploy a pair of communications satellites for commercial operator SES. This is one of three Atlas V launches currently slated for the tail end of 2022, with deployment of JPSS-2, a military weather satellite, slated for the start of November and the US Space Force 51 (USSF-51) mission tracking no earlier than December.

(Lead photo: Delta IV Heavy and NROL-91 ascend toward orbit. Credit: Jack Beyer for NSF)

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