Last week, we poured our morning coffee, powered up our laptop and phone, and prepared to engage the day.
It wasn’t long before the messages started pouring in. ‘Bright fireball over the U.S. West Coast!’ ‘Major event lights up the California skies!’ and variations thereof. Memories of Chelyabinsk came immediately to mind. A bit of digging around ye ole web revealed video and a few authentic stills from the event.
Now, I always like to look these over myself before reading just what other experts might think. Chelyabinsk immediately grabbed our attention when we saw the first videos recording the shock wave of sound generated by the blast. ‘That sucker was close,’ we realized.
Thursday’s (Wednesday evening Pacific Time) event was less spectacular, but still interesting: the nighttime reentry of the Long March CZ-7 rocket body NORAD ID 2016-042E as it broke up over the U.S. West Coast.
How do we know this, and what do we look for? Is that flash a meteor, bolide, reentry or something stranger still?
Most good meteor footage comes from video recorders that are already up and running when the event occurs, to include security and dashboard cameras, and mobile phones already recording another event, such as a concert or game. How fast can YOU have your smartphone camera out and running? We only recently learned that a quick double tap of the home button will bring the camera on our Android to bear, no unlock needed.
If the event occurs on a Friday or Saturday night with lots of folks out on the town on a clear evening, we might see multiple captures come streaming-in of the event. Just such a fireball was witnessed over the United Kingdom on Friday evening, September 21st, 2012.
Likewise, the fakes are never far behind. We’ve seen ’em all, though you’re welcome to try and stump us. Such ‘meteor-wrongs’ that are commonly circulated as authentic are the reentry of Mir, the 1992 Peekskill meteor, Chelyabinsk, the reentry of Hayabusa, and screen grabs from the flick Armageddon… has anyone ever been fooled by this one?
Meteors generally have a very swift motion, and occur with a greater frequency as the observer rotates forward into the path of Earth’s motion around the Sun past local midnight. Remember, it’s the front of the windshield that picks up the bugs rolling down the highway.
Evening meteors, however, can have a dramatic slow, stately motion across the sky, as they struggle to catch up with the Earth. If they reach a brilliance of magnitude -14 — about one whole magnitude brighter than a Full Moon — said meteor is known as a bolide.
Sometimes, such a fireball can begin shedding fiery debris, in a dramatic display known as a meteor train or meteor precession. Such an event was witnessed over the northeastern United States on July 20th, 1860.
Bright meteors may exhibit colors, hinting at chemical competition. Green for nickel (Not kryptonite!) is typically seen. MeteoriteMen’s Geoffrey Notkin once told us a good rule of thumb: if you hear an accompanying sonic boom a few minutes after seeing a meteor, it’s close. Folks often think what they saw went down behind a hill or tree, when it was actually likely more than 50 miles distant — if it hit the ground at all.
Is that a meteor or a reentry? Reentries move slower still, and will shed lots of debris. Here’s what we’re looking at to judge suspect sighting as a reentry:
Heavens-Above: A great clearing house for satellite passes by location. One great tool is that Heavens-Above will generate a pass map for your location juxtaposed over a sky chart.
Aerospace Corp current reentries: Follows upcoming reentries of larger debris with refined orbits.
Space-Track: The U.S. Joint Space Operations Command’s tracking center for artificial objects in orbit around Earth. Access is available to backyard satellite spotters with free registration. The most accurate source for swiftly evolving orbital elements.
SeeSat-L: This message board always lights up with chatter whenever a possible reentry lights up the skies worldwide.
Stranger Skies
Bizarre sights await the keen eyed. A tumbling rocket booster can often flare in a manner similar to Iridium satellites. Satellites way out in geostationary orbit can flare briefly into naked eye visibility during ‘GEOSat flare season’ near the weeks surrounding either equinox.
Some gamma ray bursts, such as GRB 080319B flare up briefly above magnitude +6 into naked eye visibility from far across the Universe. As of yet, there’s never been a reliable observer sighting of such an event, though it should be possible… probably someone far back in humanity’s history witnessed just such a brief flash in the sky, pausing silently to wonder just what it was…
Going further back still, a nearby supernova or gamma-ray burst would leave a ghostly blue afterglow from Cerenkov radiation as it pummeled our atmosphere… though it would be a deadly planet-sterilizing indigo glow, not something you’d want to see. Thankfully, we live in the ‘Era of Mediocrity,’ safely outside of the 25-50 light year ‘kill zone’ for any potential supernova.
And what if those lights in the sky really were the vanguard of an alien invasion force? Well, if they really did land rayguns ablaze on the White House lawn, you’ll read it first here on Universe Today!
KENNEDY SPACE CENTER, FL – SpaceX founder Elon Musk’s daring dream of rocket recycling and reusability is getting closer and closer to reality with each passing day. After a breathtaking series of experimental flight tests aimed at safely landing the firms spent Falcon 9 first stages on land and at sea over the past half year the bold effort achieved another major milestone by just completing the first full duration test firing of one of those landed boosters.
On Thursday, July 28, SpaceX engineers successful conducted a full duration static engine test firing of the 156-foot-tall (47-meter) recovered Falcon 9 first stage booster while held down on a test stand at the company’s rocket development test facility in McGregor, Texas. The engines fired up for about two and a half minutes.
The SpaceX team has been perfecting the landing techniques by adopting lessons learned after each landing campaign attempt.
What are the lessons learned so far from the first stage landings and especially the hard landings? Are there any changes being made to the booster structure? How well did the landing burn scenario perform?
During SpaceX’s recent CRS-9 launch campaign media briefings at NASA’s Kennedy Space Center on July 18, I asked SpaceX VP Hans Koenigsmann for some insight.
“We learned a lot … from the landings,” Hans Koenigsmann, SpaceX vice president of Flight Reliability, told Universe Today during the recent media briefings for the SpaceX CRS-9 space station cargo resupply launch on July 18.
“There are no structural changes first of all.”
“The key thing is to protect the engines,” Koenigsmann elaborated, while they are in flight and “during reentry”.
The SpaceX Falcon 9 first stage is outfitted with four landing legs at the base and four grid fins at the top to conduct the landing attempts.
“In general I think the landing concept with the legs, and the number of burns and the way we perform those seems to work OK,” Koenigsmann told Universe Today.
After separating from the second stage at hypersonic speeds of up to some 4000 mph, the first stage engines are reignited to reverse course and do a boost backburn back to the landing site and slow the rocket down for a soft landing, via supersonic retropulsion.
Proper engine performance is critical to enabling a successful touchdown.
“The key thing is to protect the engines – and make sure that they start up well [in space during reentry],” Koenigsmann explained. “And in particular the hot trajectory, so to speak, like the ones that comes in after a fast payload, like the geo-transfer payload basically.”
“Those engines need to be protected so that they start up in the proper way. That’s something that we learned.”
Elon Musk’s goal is to radically slash the cost of launching rockets and access to space via rocket reuse – in a way that will one day lead to his vision of a ‘City on Mars.’
SpaceX hopes to refly a once flown booster later this year, sometime in the Fall, using the ocean landed Falcon from NASA’s CRS-8 space station mission launched in April, says Koenigsmann.
But the company first has to prove that the used vehicle can survive the extreme and unforgiving stresses of the violent spaceflight environment before they can relaunch it.
The July 28 test firing is part of that long life endurance testing and involved igniting all nine used first stage Merlin 1D engines housed at the base of a used landed rocket.
The Falcon 9 first stage generates over 1.71 million pounds of thrust when all nine Merlin engines fire up on the test stand for a duration of up to three minutes – the same as for an actual launch.
Watch the engine test in this SpaceX video:
Video Caption: Falcon 9 first stage from May 2016 JCSAT mission was test fired, full duration, at SpaceX’s McGregor, Texas rocket development facility on July 28, 2016. Credit: SpaceX
Just 10 minutes after launching the JCSAT-14 telecom satellite to a Geostationary Transfer Orbit (GTO), the used first stage relit a first stage Merlin 1D engine.
It conducted a series of three recovery burns to maneuver the rocket to a designated landing spot at sea or on land and rapidly decelerate it from supersonic speeds for a propulsive soft landing, intact and upright using a quartet of landing legs that deploy in the final moments before a slow speed touchdown.
However, although the landing was upright and intact, this particular landing was also classed as a ‘hard landing’ because the booster landed at a higher velocity and Merlin 1D first stage engines did sustain heavy damage as seen in up close photos and acknowledged by Musk.
“Most recent rocket took max damage, due to v high entry velocity. Will be our life leader for ground tests to confirm others are good,” Musk tweeted at the time.
Nevertheless it all worked out spectacularly and this was the first one to be recovered from the much more demanding, high velocity trajectory delivering a satellite to GTO.
Indeed prior to liftoff, Musk had openly doubted a successful landing outcome, since this first stage was flying faster and at a higher altitude at the time of separation from the second stage and thus was much more difficult to slow down and maneuver back to the ocean based platform compared to ISS missions, for example.
So although this one cannot be reflown, it still serves another great purpose for engineers seeking to determining the longevity of the booster and its various components – as now audaciously demonstrated by the July 28 engine test stand firing.
“We learned a lot even on the missions where things go wrong with the landing, everything goes well on the main mission of course,” said Koenigsmann.
Altogether SpaceX has successfully soft landed and recovered five of their first stage Falcon 9 boosters intact and upright since the history making first ever land landing took place just seven months ago in December 2015 at Cape Canaveral Air Force Station in Florida.
See the stupendous events unfold in up close photos and videos herein.
Following each Falcon 9 launch and landing attempt, SpaceX engineers assess the voluminous and priceless data gathered, analyze the outcome and adopt the lessons learned.
CRS-9 marks only the second time SpaceX has attempted a land landing of the 15 story tall first stage booster back at Cape Canaveral Air Force Station – at the location called Landing Zone 1 (LZ 1).
Watch this exquisitely detailed up close video showing the CRS-9 first stage landing at LZ 1, as shot by space colleague Jeff Seibert from the ITL causeway at CCAFS- which dramatically concluded with multiple shockingly loud sonic booms rocketing across the Space Coast and far beyond and waking hordes of sleepers:
Video caption: This was the second terrestrial landing of a SpaceX Falcon 9 booster on July 18, 2016. It had just launched the CRS9 Dragon mission towards the ISS. The landing took place at LZ1, formerly known as Pad 13, located on CCAFS and caused a triple sonic boom heard 50 miles away. Credit: Jeff Seibert
The history making first ever ground landing successfully took place at Landing Zone 1 (LZ 1) on Dec. 22, 2015 as part of the ORBCOMM-2 mission. Landing Zone 1 is built on the former site of Space Launch Complex 13, a U.S. Air Force rocket and missile testing range.
SpaceX also successfully recovered first stages three times in a row at sea this year on an ocean going drone ship barge using the company’s OCISLY Autonomous Spaceport Drone Ship (ASDS) on April 8, May 6 and May 27.
OCISLY is generally stationed approximately 400 miles (650 kilometers) off shore and east of Cape Canaveral, Florida in the Atlantic Ocean. The barge arrives back in port at Port Canaveral several days after the landing, depending on many factors like weather, port permission and the state of the rocket.
The rocket apparently ran out of liquid oxygen fuel in the final moments before touchdown, hit hard, tipped over and pancaked onto the deck.
“Looks like early liquid oxygen depletion caused engine shutdown just above the deck,” Musk explained via twitter at the time.
“Looks like thrust was low on 1 of 3 landing engines. High g landings v sensitive to all engines operating at max.”
“We learned a lot even on the mission where things go wrong with the landing,” Koenigsmann explained. “Everything goes well on the main mission of course.”
“That’s actually something where you have successful deploy and the landing doesn’t quite work- and yet its the landing that gets all the attention.”
“But even on those landings we learned a lot. In particular on the last landing [from Eutelsat launch] we learned a lot.”
“We believe we found a way to operationally protect these engines and to make it safer for them to start up – and to come up to full thrust and stay at full thrust.”
What exactly does “protecting the engines” mean “in flight?”
“Yes I mean protecting the engines during reentry,” Koenigsmann told me.
“That’s when the engines get hot. We enter with the engines facing the flow. So its basically the engines directly exposed to the hot flow. And that’s when you need to protect the engines and the gases and liquids that are in the engines. To make sure that nothing boils off and does funny things.”
“So all in all these series of drone ship landings has been extremely successful, even when we didn’t recover all the first stages [fully intact].”
Watch for Ken’s continuing SpaceX and CRS-9 mission coverage where he reported onsite direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Video caption: SpaceX Falcon 9 lifts off with Dragon CRS-9 resupply ship bound for the International Space Station on July 18, 2016 at 12:45 a.m. EDT from Space Launch Complex 40 at Cape Canaveral Air Force Station, Fl, as seen in this up close video from Mobius remote camera positioned at pad. Credit: Ken Kremer/kenkremer.com
Watch this CRS-9 launch and landing video compilation from space colleague Mike Wagner:
Video caption: SpaceX CRS-9 Launch and Landing compilation on 7/18/2016. Local papers reported 911 calls for a loud explosion up to 75 miles away. This sonic boom seemed louder than the first landing at the Cape in Dec. 2015. Credit: USLaunchReport
Ever since Musk founded SpaceX is 2002, with the intention of eventually colonizing Mars, every move he has made has been the subject of attention. And for the past two years, a great deal of this attention has been focused specifically on the development of the Falcon Heavy rocket and the Dragon 2 capsule – the components with which Musk hopes to mount a lander mission to Mars in 2018.
Among other things, there is much speculation about how much this is going to cost. Given that one of SpaceX’s guiding principles is making space exploration cost-effective, just how much money is Musk hoping to spend on this important step towards a crewed mission? As it turns out, NASA produced some estimates at a recent meeting, which indicated that SpaceX is spending over $300 million on its proposed Mars mission.
These estimates were given during a NASA Advisory Council meeting, which took place in Cleveland on July 26th between members of the technology committee. During the course of the meeting, James L. Reuter – the Deputy Associate Administrator for Programs at NASA’s Space Technology Mission Directorate – provided an overview of NASA’s agreement with SpaceX, which was signed in December of 2014 and updated this past April.
In accordance with this agreement, NASA will be providing support for the company’s plan to send an uncrewed Dragon 2 capsule (named “Red Dragon”) to Mars by May of 2018. Intrinsic to this mission is the plan to conduct a propulsive landing on Mars, which would test the Dragon 2‘s SuperDraco Descent Landing capability. Another key feature of this mission will involve using the Falcon Heavy to deploy the capsule.
The terms of this agreement do not involve the transfer of funds, but entails active collaboration that would be to the benefit parties. As Reuters indicated in his presentation, which NASA’s Office of Communications shared with Universe Today via email (and will be available on the STMD’s NASA page soon):
“Building on an existing no-funds-exchanged collaboration with SpaceX, NASA is providing technical support for the firm’s plan to attempt to land an uncrewed Dragon 2 spacecraft on Mars. This collaboration could provide valuable entry, descent and landing (EDL) data to NASA for our journey to Mars, while providing support to American industry. We have similar agreements with dozens of U.S. commercial, government, and non-profit partners.”
Further to this agreement is NASA’s commitment to a budget of $32 million over the next four years, the timetable of which were partially-illustrated in the presentation: “NASA will contribute existing agency resources already dedicated to [Entry, Descent, Landing] work, with an estimated value of approximately $32M over four years with approximately $6M in [Fiscal Year] 2016.”
According to Article 21 of the Space Act Agreement between NASA and SpaceX, this will include providing SpaceX with: “Deep space communications and telemetry; Deep space navigation and trajectory design; Entry, descent and landing system analysis and engineering support; Mars entry aerodynamic and aerothermal database development; General interplanetary mission advice and hardware consultation; and planetary protection consultation and advice.”
For their part, SpaceX has not yet disclosed how much their Martian mission plan will cost. But according to Jeff Foust of SpaceNews, Reuter provided a basic estimate of about $300 million based on a 10 to 1 assessment of NASA’s own financial commitment: “They did talk to us about a 10-to-1 arrangement in terms of cost: theirs 10, ours 1,” said Reuter. “I think that’s in the ballpark.”
As for why NASA has chosen to help SpaceX make this mission happen, this was also spelled out in the course of the meeting. According to Reuter’s presentation: “NASA conducted a fairly high-level technical feasibility assessment and determined there is a reasonable likelihood of mission success that would be enhanced with the addition of NASA’s technical expertise.”
Such a mission would provide NASA with valuable landing data, which would prove very useful when mounting its crewed mission in the 2030s. Other items discussed included NASA-SpaceX collaborative activities for the remainder of 2016 – which involved a “[f]ocus on system design, based heavily on Dragon 2 version used for ISS crew and cargo transportation”.
It was also made clear that the Falcon Heavy, which SpaceX is close to completing, will serve as the launch vehicle. SpaceX intends to conduct its first flight test (Falcon Heavy Demo Flight 1) of the heavy-lifter in December of 2016. Three more test flights are scheduled to take place between 2017 and the launch of the Mars lander mission, which is still scheduled for May of 2018.
In addition to helping NASA prepare for its mission to the Red Planet, SpaceX’s progress with both the Falcon Heavy and Dragon 2 are also crucial to Musk’s long-term plan for a crewed mission to Mars – the architecture of which has yet to be announced. They are also extremely important in the development of the Mars Colonial Transporter, which Musk plans to use to create a permanent settlement on Mars.
And while $300 million is just a ballpark estimate at this juncture, it is clear that SpaceX will have to commit considerable resources to the enterprise. What’s more, people must keep in mind that this would be merely the first in a series of major commitments that the company will have to make in order to mount a crewed mission by 2024, to say nothing of building a Martian colony!
In the meantime, be sure to check out this animation of the Crew Dragon in flight:
Welcome back to Constellation Friday! Today, in honor of our dear friend and contributor, Tammy Plotner, we examine the Caelum constellation. Enjoy!
In the 2nd century CE, Greek-Egyptian astronomer Claudius Ptolemaeus (aka. Ptolemy) compiled a list of the then-known 48 constellations. Until the development of modern astronomy, his treatise (known as the Almagest) would serve as the authoritative source on astronomy. This list has since come to be expanded to include the 88 constellation that are recognized by the International Astronomical Union (IAU) today.
One of these constellations is Caelum, which was discovered in in the 1750s by French astronomer Nicolas Louis de Lacaille, and is now counted among the 88 IAU-recognized constellations. It is the eight-smallest constellation, with an area just less than that of Corona Australis (another southern constellation), and is bordered by the Dorado, Pictor, Horologium, Eridanus, Lepus and Columba constellations.
Name and Meaning:
The name Caelum, in Latin, literally means “chisel”, though the word can also mean ‘the heavens’. According to an antiquated school of thought, the sky (caelum, ‘sky, heaven, the heavens’) is rounded, spinning, and burning; and the sky is called by its name because it has the figures of the constellations impressed into it – just like an engraved (caelare) vessel. In Lacaille’s imagination, he saw this constellation as therefore representing “les Burins”, or the tools of a sculptor.
Notable Features:
The constellation of Caelum has very little to offer observers using either binoculars or telescopes, with only four primary stars visible to the unaided eye and only eight stars with Bayer/Flamsteed designations. However, Gamma Caeli is a widely separated binary star system with a distance of 0.22°. It is composed of a magnitude 4.5 red giant and a magnitude 6.34 white giant.
For an extreme challenge, try locating Alpha Caeli. At an approximate distance of 65.7 light years from Earth, this yellow-white F-type main sequence dwarf with an apparent magnitude of +4.44 has an an extremely faint companion. It is magnitude 13, with a position angle of 121º and a separation 6.6″.
If you like long-term variable stars, you could always look for R Caeli, a long-term Mira-type that ranges from from 6.7 to 13.7 every 391 days. Or how about X Caeli, a Delta-Scuti type star? It’s changes are much faster – but far less noticeably. It changes by one tenth of a magnitude (6.3 to 6.4) every three hours and fourteen minutes.
For those looking for Deep Sky Objects, a big telescope is necessary. This is because NGC 1679 is about all there is to see, and it doesn’t appear lightly. Located about two degree south of Zeta Caeli, there’s not even a magnitude guess at this small spiral galaxy – but it does measure about 3.2 arc minutes, and appears to be an irregularly-shaped galaxy. There are indications that it may be a dwarf starburst galaxy.
History of Observation:
Caelum was introduced by Nicolas Louis de Lacaille in the 1750s to help chart the southern hemisphere skies. Lacaille gave the constellation the French name Burin, which was originally Latinized to Caelum Scalptorium (“The Engravers’ Chisel”). English astronomer Francis Baily would alter shorten this name to Caelem, as suggested by fellow astronomer John Herschel.
In Lacaille’s original chart, the constellation was shown both as two types of chisels – a burin (a steel-engraving chisl) and an échoppe (an etching chisel) – although it has come to be recognized simply as a chisel.
Finding Caelum:
Though it is quite small and faint, locating Caelum is not difficult if you know where to look. Using stellar coordinates, you can find it by looking to the first quadrant of the southern hemisphere (SQ1), and then tracing it to between latitudes +40° and -90°. Or, start by picking out Canopus (the brightest of Carina‘s stars), pan due east, and then spot the small chisel between its neighbors.
Caelum is bordered by Dorado and Pictor to the south, Horologium and Eridanus to the east, Lepus to the north, and Columba to the west. The Caelum constellation occupies an area of 125 square degrees, and can be seen during the month of January at around 9 pm.
Seeing a fireball erupt in the sky is not an unusual occurrence. Especially during late July, when the Delta Aquirid meteor shower is so near to peaking. At times like this, dozens of fiery objects can be observed streaking across the atmosphere. But on this occasion, the light show that was spotted over Las Vegas earlier this week had a stranger cause.
The fireball appeared on Wednesday July 27th, at around 9:30 p.m. (Pacific Time), and could be seen from California to Utah. News and videos of the fiery apparition were quickly posted on social media, where astronomers began to notice something odd. And as it turned out, it was NOT the result of a meteor shower, but was in fact was the second stage of a rocket hitting the atmosphere, courtesy of the Chinese National Space Agency.
Such was the conclusion of Phil Plait, an astronomer and writer for Slate. After seeing a video shot of the display, he took to Twitter to question the explanation that it was the result of the Delta Aquirids. Based on his observations, he asserted that the event was actually the result of space debris burning up in the atmosphere.
His posts encouraged Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics, to do some checking. After looking into the matter, McDowell determined that the cause was a spent stage of a Chinese rocket falling back to Earth. As he posted on Twitter:
“Observation reports from Utah indicate the second stage from the first Chang Zheng 7 rocket, launched Jun 25, reentered at 0440 UTC.”
The Chang Zheng 7 is the latest in a line of Chinese rockets. It’s name translates to “Long March”, in honor of Mao’s forces marching into China’s interior during the Second Sino-Japanese War (1937-1945). A liquid-fueled carrier rocket designed to handle medium to heavy payloads, this rocket was developed to replace the Chinese Space Agency’s Long March 2F crew-rated launch vehicle.
This rocket is expected to play a critical role in creation of the Chinese Space Station, and will serve as the launch vehicle for the Tianzhou robotic cargo spacecraft in the meantime. Monday, June 25th was the inaugural launch of the rocket, and after the second stage was spent, it re-entered the Earth’s atmosphere at 04:36 UTC (9:36 p.m. Pacific Time) on Wednesday.
The 2nd stage then began to burn up as it moved across the sky from southwest to northeast, moving at speeds of 20,000 km/h (12,427 mph). It eventually disintegrated after becoming visible all across the south-western US, burning up at an altitude of about 100 km (62.13 mi). At this point, observers reported hearing a large boom, and many were fortunate enough to get the whole thing on video (as you can see from the ones included here).
While discarded space vehicles burn up in the atmosphere all the time, this was one of those rare occasions when the object happened to weight 6 metric tons (6.6 short tons)! We’re just fortunate that space launches are so rigorously planned so as to prevent them from causing accidents and extensive property damage, unlike certain meteorites that show up uninvited (looking at you Chelyabinsk meteor!)
CAPE CANAVERAL AIR FORCE STATION, FL — Riding atop the crackling roar of an Atlas V rocket, a clandestine surveillance satellite for our nation’s spy masters was carried aloft by a powerful booster from the Florida space coast to an undisclosed orbit at breakfast time today, Thursday, July 28.
The United Launch Alliance (ULA) Atlas V rocket carrying the NROL-61 surveillance satellite for the National Reconnaissance Office (NRO) lifted off from Space Launch Complex-41 right at the appointed time of 8:37 a.m. EDT this morning with approximately 1.5 million pounds of thrust.
The top secret NROL-61 satellite bolted on top and inside the 4 meter diameter nose cone was launched in support of US national defense and is vital to US national security.
“Thank you to the entire mission team for years of hard work and collaboration on today’s successful launch of NROL-61. We are proud the U.S. Air Force and NRO Office of Space Launch have entrusted ULA with delivering this critical asset for our nation’s security,” said Laura Maginnis, ULA vice president of Custom Services, in a statement.
“Our continued one launch at a time focus and exceptional teamwork make launches like today’s successful.”
The launch was webcast live by ULA and featured video recorded call in questions about spaceflight from the general public – especially children!
The rocket roared off pad 41 atop an ever expanding plume of smoke and ash into a brilliant and cloudless blue sky under absolutely ideal weather conditions with clear lines of sight enjoyed by hordes of spectators gathered here from near and far, and lining the space coast beaches and surrounding viewing areas.
Many local area hotels were packed with space enthusiasts hoping for a space spectacular at this unusually convenient launch time – and they were not disappointed!!
Because the Atlas rocket was equipped with a pair of powerful solid rocket boosters to augment its liftoff thrust, the smoke plume was visible for as long as we could see it.
The rocket soon arced over, racing southeasterly to orbit and towards the African continent.
Virtually everything about the clandestine payload, its mission, purpose and goals are classified top secret on a mission of vital importance to America’s national security and defense needs.
The NRO is the government agency that runs a vast fleet of powerful orbital assets hosting a multitude of the most advanced, wide ranging and top secret capabilities.
The most recent NRO payload, known as NROL 37, was just launched by ULA last month on their Delta IV Heavy – the most powerful rocket in the world on June 11 – read my story here.
The venerable ULA Atlas V rocket sports a 100% record of launch success and its unusual for technical issues to hold up a launch. The ever changeable Florida weather is another matter entirely.
The NROL-61 mission counts as ULA’s sixth launch of 2016 and the 109th overall since the company was founded in 2006.
The 20 story tall Atlas V launched in its 421 configuration – the same as what will be used for manned launches with the crewed Boeing ‘Starliner’ space taxi carrying astronaut crews to the International Space Station.
This was the sixth Atlas V to launch in the 421 configuration.
The Atlas 421 vehicle includes a 4-meter diameter Extra Extended Payload Fairing (XEPF) payload fairing and two solid rocket boosters that augment the first stage. The Atlas booster for this mission was powered by the RD AMROSS RD-180 engine and the Centaur upper stage was powered by the Aerojet Rocketdyne RL10C-1 engine.
The RD-180 burns RP-1 (Rocket Propellant-1 or highly purified kerosene) and liquid oxygen and delivers 860,200 lb of thrust at sea level.
The strap on solids deliver approximately 500,000 pounds of thrust.
The solids were jettisoned about 2 minutes after liftoff.
Virtually everything about the clandestine payload, its mission, purpose and goals are classified top secret.
The NRO is the government agency that runs a vast fleet of powerful orbital assets hosting a multitude of the most advanced, wide ranging and top secret capabilities.
The possible roles for the reconnaissance payload include signals intelligence, eavesdropping, imaging and spectroscopic observations, early missile warnings and much more.
The NRO was formed in response to the Soviet launch of Sputnik and secretly created on September 6, 1961.
“The purpose is overseeing all satellite and overflight reconnaissance projects whether overt or covert. The existence of the organization is no longer classified today, but we’re still pressing to perform the functions necessary to keep American citizens safe,” according to the official NRO website.
Watch for Ken’s continuing on site reports direct from Cape Canaveral Air Force Station, the Kennedy Space Center and the ULA Atlas launch pad.
Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Learn more about SLS and Orion crew vehicle, SpaceX CRS-9 rocket launch, ISS, ULA Atlas and Delta rockets, Juno at Jupiter, Orbital ATK Antares & Cygnus, Boeing, Space Taxis, Mars rovers, NASA missions and more at Ken’s upcoming outreach events:
July 27-28: “ULA Atlas V NRO Spysat launch July 28, SpaceX launch to ISS on CRS-9, SLS, Orion, Juno at Jupiter, ULA Delta 4 Heavy NRO spy satellite, Commercial crew, Curiosity explores Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
Welcome, come in to the 468th and 469th Carnival of Space – we combined these two since it’s summer break for a lot of folks! The Carnival is a community of space science and astronomy writers and bloggers, who submit their best work each week for your benefit. I’m Susie Murph, part of the team at Universe Today and CosmoQuest. So now, on to this week’s stories! Continue reading “Carnival of Space #468-469”
Atomic theory has come a long way over the past few thousand years. Beginning in the 5th century BCE with Democritus‘ theory of indivisible “corpuscles” that interact with each other mechanically, then moving onto Dalton’s atomic model in the 18th century, and then maturing in the 20th century with the discovery of subatomic particles and quantum theory, the journey of discovery has been long and winding.
Arguably, one of the most important milestones along the way has been Bohr’ atomic model, which is sometimes referred to as the Rutherford-Bohr atomic model. Proposed by Danish physicist Niels Bohr in 1913, this model depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits (defined by their energy levels) around the center.
Atomic Theory to the 19th Century:
The earliest known examples of atomic theory come from ancient Greece and India, where philosophers such as Democritus postulated that all matter was composed of tiny, indivisible and indestructible units. The term “atom” was coined in ancient Greece and gave rise to the school of thought known as “atomism”. However, this theory was more of a philosophical concept than a scientific one.
It was not until the 19th century that the theory of atoms became articulated as a scientific matter, with the first evidence-based experiments being conducted. For example, in the early 1800’s, English scientist John Dalton used the concept of the atom to explain why chemical elements reacted in certain observable and predictable ways. Through a series of experiments involving gases, Dalton went on to develop what is known as Dalton’s Atomic Theory.
This theory expanded on the laws of conversation of mass and definite proportions and came down to five premises: elements, in their purest state, consist of particles called atoms; atoms of a specific element are all the same, down to the very last atom; atoms of different elements can be told apart by their atomic weights; atoms of elements unite to form chemical compounds; atoms can neither be created or destroyed in chemical reaction, only the grouping ever changes.
Discovery of the Electron:
By the late 19th century, scientists also began to theorize that the atom was made up of more than one fundamental unit. However, most scientists ventured that this unit would be the size of the smallest known atom – hydrogen. By the end of the 19th century, this would change drastically, thanks to research conducted by scientists like Sir Joseph John Thomson.
Through a series of experiments using cathode ray tubes (known as the Crookes’ Tube), Thomson observed that cathode rays could be deflected by electric and magnetic fields. He concluded that rather than being composed of light, they were made up of negatively charged particles that were 1ooo times smaller and 1800 times lighter than hydrogen.
This effectively disproved the notion that the hydrogen atom was the smallest unit of matter, and Thompson went further to suggest that atoms were divisible. To explain the overall charge of the atom, which consisted of both positive and negative charges, Thompson proposed a model whereby the negatively charged “corpuscles” were distributed in a uniform sea of positive charge – known as the Plum Pudding Model.
These corpuscles would later be named “electrons”, based on the theoretical particle predicted by Anglo-Irish physicist George Johnstone Stoney in 1874. And from this, the Plum Pudding Model was born, so named because it closely resembled the English desert that consists of plum cake and raisins. The concept was introduced to the world in the March 1904 edition of the UK’sPhilosophical Magazine, to wide acclaim.
The Rutherford Model:
Subsequent experiments revealed a number of scientific problems with the Plum Pudding model. For starters, there was the problem of demonstrating that the atom possessed a uniform positive background charge, which came to be known as the “Thomson Problem”. Five years later, the model would be disproved by Hans Geiger and Ernest Marsden, who conducted a series of experiments using alpha particles and gold foil – aka. the “gold foil experiment.”
In this experiment, Geiger and Marsden measured the scattering pattern of the alpha particles with a fluorescent screen. If Thomson’s model were correct, the alpha particles would pass through the atomic structure of the foil unimpeded. However, they noted instead that while most shot straight through, some of them were scattered in various directions, with some going back in the direction of the source.
Geiger and Marsden concluded that the particles had encountered an electrostatic force far greater than that allowed for by Thomson’s model. Since alpha particles are just helium nuclei (which are positively charged) this implied that the positive charge in the atom was not widely dispersed, but concentrated in a tiny volume. In addition, the fact that those particles that were not deflected passed through unimpeded meant that these positive spaces were separated by vast gulfs of empty space.
By 1911, physicist Ernest Rutherford interpreted the Geiger-Marsden experiments and rejected Thomson’s model of the atom. Instead, he proposed a model where the atom consisted of mostly empty space, with all its positive charge concentrated in its center in a very tiny volume, that was surrounded by a cloud of electrons. This came to be known as the Rutherford Model of the atom.
The Bohr Model:
Subsequent experiments by Antonius Van den Broek and Niels Bohr refined the model further. While Van den Broek suggested that the atomic number of an element is very similar to its nuclear charge, the latter proposed a Solar-System-like model of the atom, where a nucleus contains the atomic number of positive charge and is surrounded by an equal number of electrons in orbital shells (aka. the Bohr Model).
In addition, Bohr’s model refined certain elements of the Rutherford model that were problematic. These included the problems arising from classical mechanics, which predicted that electrons would release electromagnetic radiation while orbiting a nucleus. Because of the loss in energy, the electron should have rapidly spiraled inwards and collapsed into the nucleus. In short, this atomic model implied that all atoms were unstable.
The model also predicted that as electrons spiraled inward, their emission would rapidly increase in frequency as the orbit got smaller and faster. However, experiments with electric discharges in the late 19th century showed that atoms only emit electromagnetic energy at certain discrete frequencies.
Bohr resolved this by proposing that electrons orbiting the nucleus in ways that were consistent with Planck’s quantum theory of radiation. In this model, electrons can occupy only certain allowed orbitals with a specific energy. Furthermore, they can only gain and lose energy by jumping from one allowed orbit to another, absorbing or emitting electromagnetic radiation in the process.
These orbits were associated with definite energies, which he referred to as energy shells or energy levels. In other words, the energy of an electron inside an atom is not continuous, but “quantized”. These levels are thus labeled with the quantum number n (n=1, 2, 3, etc.) which he claimed could be determined using the Ryberg formula – a rule formulated in 1888 by Swedish physicist Johannes Ryberg to describe the wavelengths of spectral lines of many chemical elements.
Influence of the Bohr Model:
While Bohr’s model did prove to be groundbreaking in some respects – merging Ryberg’s constant and Planck’s constant (aka. quantum theory) with the Rutherford Model – it did suffer from some flaws which later experiments would illustrate. For starters, it assumed that electrons have both a known radius and orbit, something that Werner Heisenberg would disprove a decade later with his Uncertainty Principle.
In addition, while it was useful for predicting the behavior of electrons in hydrogen atoms, Bohr’s model was not particularly useful in predicting the spectra of larger atoms. In these cases, where atoms have multiple electrons, the energy levels were not consistent with what Bohr predicted. The model also didn’t work with neutral helium atoms.
The Bohr model also could not account for the Zeeman Effect, a phenomenon noted by Dutch physicists Pieter Zeeman in 1902, where spectral lines are split into two or more in the presence of an external, static magnetic field. Because of this, several refinements were attempted with Bohr’s atomic model, but these too proved to be problematic.
In the end, this would lead to Bohr’s model being superseded by quantum theory – consistent with the work of Heisenberg and Erwin Schrodinger. Nevertheless, Bohr’s model remains useful as an instructional tool for introducing students to more modern theories – such as quantum mechanics and the valence shell atomic model.
We’re in for a celestial show from two of the sky’s glitterati this week. On Friday morning July 29 around 10:00 UT (5 a.m. CDT), the crescent Moon will occult the star Aldebaran from the eastern and southern U.S. south of a line from Toledo, Ohio through St. Louis, Tulsa and El Paso, Texas. North of that line, the Moon will slide just south of the star in a spectacular conjunction. But the real action lies within a half-mile of either side of the line, where lucky observers will see a grazing occultation.
As the Moon’s orbital motion carries it eastward at the rate of one lunar diameter per hour, Aldebaran will appear to approach the sunlit northern cusp and then scrape along the Moon’s northern limb. You’ll need binoculars or a small telescope to see the initial approach, but once star reaches the semi-dark, earthlit portion of the Moon, the graze will be visible with the naked eye.
The edge or limb of the Moon appears smooth to the eye, but it’s rife with polar mountain peaks. As Aldebaran creeps along the craggy limb, it will repeatedly flash in and out of view as peaks and cliffs momentarily block it from sight. And here’s the truly amazing thing. Observers along the western section of the graze line, where the event takes place in fairly dark sky, can watch the star blink in and out of view without optical aid when it reaches the dark part of the lunar disk. Wow!
Aldebaran is no small star. An orange giant 67 light years from Earth, it’s 44 times the diameter of the Sun. That means that sometimes only a part of the star at a time will covered at a time in some cases, so the length of the flashes will vary. According to David Dunham, president of the International Occultation Timing Association (IOTA), Aldebaran will disappear for one-tenth of a second up to a second as the Moon rolls east, allowing some observers to sense the size of the star. Wow x 100!
Skywatchers further east along the graze line and in other areas where the occultation / conjunction takes place after sunrise shouldn’t pass up the chance to see the event. During last October’s occultation of Aldebaran, I was able to see and photograph the star in my 10-inch scope in daylight no problem. The moon will be closer to the Sun this time around, but give it try anyway. This is the best grazing occultation of Aldebaran visible from North America in the current 4-year series.
For the many who live either north or south of the graze line, the views will still be fantastic. You’ll either see an occultation and subsequent reappearance of the star at the dark limb … or a fine conjunction. The forecast looks good for my city, so I plan on heading out to watch an orange giant meet the skinny Moon. I wish you clear skies and happy shooting!
For more information about the event including detailed weather forecasts and grazing maps, check out the IOTA’s public announcement page. Click here for Universal Times for the disappearance and reappearance of the star for over 1,000 cities.
Ever since astronomers first began using telescopes to get a better look at the heavens, they have struggled with a basic conundrum. In addition to magnification, telescopes also need to be able to resolve the small details of an object in order to help us get a better understanding of them. Doing this requires building larger and larger light-collecting mirrors, which requires instruments of greater size, cost and complexity.
However, scientists working at NASA Goddard’s Space Flight Center are working on an inexpensive alternative. Instead of relying on big and impractical large-aperture telescopes, they have proposed a device that could resolve tiny details while being a fraction of the size. It’s known as the photon sieve, and it is being specifically developed to study the Sun’s corona in the ultraviolet.
Basically, the photon sieve is a variation on the Fresnel zone plate, a form of optics that consist of tightly spaced sets of rings that alternate between the transparent and the opaque. Unlike telescopes which focus light through refraction or reflection, these plates cause light to diffract through transparent openings. On the other side, the light overlaps and is then focused onto a specific point – creating an image that can be recorded.
The photon sieve operates on the same basic principles, but with a slightly more sophisticated twist. Instead of thin openings (i.e. Fresnel zones), the sieve consists of a circular silicon lens that is dotted with millions of tiny holes. Although such a device would be potentially useful at all wavelengths, the Goddard team is specifically developing the photon sieve to answer a 50-year-old question about the Sun.
Essentially, they hope to study the Sun’s corona to see what mechanism is heating it. For some time, scientists have known that the corona and other layers of the Sun’s atmosphere (the chromosphere, the transition region, and the heliosphere) are significantly hotter than its surface. Why this is has remained a mystery. But perhaps, not for much longer.
As Doug Rabin, the leader of the Goddard team, said in a NASA press release:
“This is already a success… For more than 50 years, the central unanswered question in solar coronal science has been to understand how energy transported from below is able to heat the corona. Current instruments have spatial resolutions about 100 times larger than the features that must be observed to understand this process.”
With support from Goddard’s Research and Development program, the team has already fabricated three sieves, all of which measure 7.62 cm (3 inches) in diameter. Each device contains a silicon wafer with 16 million holes, the sizes and locations of which were determined using a fabrication technique called photolithography – where light is used to transfer a geometric pattern from a photomask to a surface.
However, in the long-run, they hope to create a sieve that will measure 1 meter (3 feet) in diameter. With an instrument of this size, they believe they will be able to achieve up to 100 times better angular resolution in the ultraviolet than NASA’s high-resolution space telescope – the Solar Dynamics Observatory. This would be just enough to start getting some answers from the Sun’s corona.
In the meantime, the team plans to begin testing to see if the sieve can operate in space, a process which should take less than a year. This will include whether or not it can survive the intense g-forces of a space launch, as well as the extreme environment of space. Other plans include marrying the technology to a series of CubeSats so a two-spacecraft formation-flying mission could be mounted to study the Sun’s corona.
In addition to shedding light on the mysteries of the Sun, a successful photon sieve could revolution optics as we know it. Rather than being forced to send massive and expensive apparatus’ into space (like the Hubble Space Telescope or the James Webb Telescope), astronomers could get all the high-resolution images they need from devices small enough to stick aboard a satellite measuring no more than a few square meters.
This would open up new venues for space research, allowing private companies and research institutions the ability to take detailed photos of distant stars, planets, and other celestial objects. It would also constitute another crucial step towards making space exploration affordable and accessible.