SpaceX Falcon 9 and Dragon poised at Cape Canaveral Space Launch Complex 40 in Florida for planned April 14 launch to the International Space Station on the CRS-6 mission. Credit: Ken Kremer/kenkremer.com
KENNEDY SPACE CENTER, FL – The skies are clear at the moment for today’s, April 14, second attempt to launch the SpaceX Falcon 9 rocket and Dragon resupply capsule on a critical mission for science bound for the International Space Station (ISS) and a bold effort to land the boosters first stage on a tiny barge in the vast expanse of the Atlantic Ocean.
The first attempt to launch the rocket and CRS-6 Dragon cargo capsule on Monday, April 13, was scrubbed just about three minutes before the scheduled blastoff at approximately 4:33 p.m. EDT from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida, due to a violation of the launch weather constraints.
Today’s second liftoff attempt 24 hours later, is slated for approximately 4:10 p.m. from SLC-41.
NASA Television plans live launch coverage starting at 3:00 p.m EDT:
You can watch the launch live on NASA TV here: http://www.nasa.gov/nasatv
SpaceX also plans live launch coverage beginning at 4:15 p.m. EDT: www.spacex.com/webcast
The launch window is instantaneous, meaning that the rocket must liftoff at the precisely appointed time. Any delays like on Monday due to weather or technical factors will force a scrub.
SpaceX Falcon 9 and Dragon erected at Cape Canaveral pad 40 in Florida in advance of April 14 launch to the International Space Station on the CRS-6 mission. Credit: Ken Kremer/kenkremer.com
Another delay would likely result in at least a 48 hour scrub.
U.S. Air Force weather forecasters from the 45th Weather Squadron currently rate the chances of favorable conditions at launch time as 60 percent GO for liftoff of the sixth SpaceX commercial resupply services mission (CRS-6) to the ISS. That’s the same as Monday’s launch attempt.
Air Force meteorologists will be watching for storms or thick clouds moving close to the launch site, as happened in the final hour prior to Monday’s try.
The Falcon 9 first stage is outfitted with four landing legs and grid fins to enable the landing attempt, which is a secondary objective of SpaceX. Cargo delivery to the station is the overriding primary objective and the entire reason for the CRS-6 mission.
Infographic shows how SpaceX Falcon 9 will fly back to Earth after next launch on CRS-6 mission to ISS. Credit: SpaceX
Overall CRS-6 is the sixth SpaceX commercial resupply services mission and the seventh trip by a Dragon spacecraft to the station since 2012.
CRS-6 marks the company’s sixth operational resupply mission to the ISS under a $1.6 Billion contract with NASA to deliver 20,000 kg (44,000 pounds) of cargo to the station during a dozen Dragon cargo spacecraft flights through 2016 under NASA’s original Commercial Resupply Services (CRS) contract.
Dragon is packed with more than 4,300 pounds (1915 kilograms) of scientific experiments, technology demonstrations, crew supplies, spare parts, food, water, clothing and assorted research gear for the six person Expedition 43 and 44 crews serving aboard the ISS.
The ship will remain berthed at the ISS for about five weeks.
Watch for Ken’s continuing onsite coverage of the CRS-6 launch from the Kennedy Space Center and Cape Canaveral Air Force Station.
The SpaceX Falcon 9 with the Dragon vessel for the CRS-6 launch is poised upright to the International Space Station for a launch at 4:10 PM eastern time from Cape Canaveral. Credit: Alex Polimeni/AmericaSpace
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
Learn more about SpaceX, Mars rovers, Orion, Antares, MMS, NASA missions and more at Ken’s upcoming outreach events:
Apr 11-14: “SpaceX, Orion, Commercial crew, Curiosity explores Mars, MMS, Antares and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
Apr 18/19: “Curiosity explores Mars” and “NASA Human Spaceflight programs” – NEAF (NorthEast Astronomy Forum), 9 AM to 5 PM, Suffern, NY, Rockland Community College and Rockland Astronomy Club
Introducing Landing Complex 1, formerly Launch Complex 13, at Cape Canaveral in Florida. Credit: SpaceX
And if you’re interested in looking back, here’s an archive to all the past Carnivals of Space. If you’ve got a space-related blog, you should really join the carnival. Just email an entry to [email protected], and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community – and community is what blogging is all about. And if you really want to help out, sign up to be a host. Send an email to the above address.
Calling all light-bucket scope owners: the folks at the European Space Agency want to enlist you in the quest to monitor Comet 67P/Churyumov-Gerasimenko from our Earthbound perspective through perihelion later this summer.
“We are looking to bring an entire community of professional and amateur observers together,” said Rosetta Coordinator of Amateur Observations for Comet 67/P C-G Padma A. Yanamandra-Fisher in a recent press release. “When else can you observe a comet at the same time a spacecraft is viewing it at close proximity and escorting it to perihelion, and be able to correlate both sets of findings?
The Rosetta story thus far has been an amazing tale of discovery. We’ve extensively chronicled the historic approach of the Rosetta spacecraft as the rubber-duck-shaped comet grew in its view here at Universe Today. The world also held its collective breath as the Philae lander, the little washing Euro- washing machine-sized spacecraft that could, descended on to the alien surface. Heck, Philae even knocked a Kardashian out of the top trending spot worldwide, a feat in and of itself.
Prospects in 2015: As of this writing, Comet 67P/C-G is 1.9 AU from the Sun and closing. The ‘P’ in ‘67/P’ stands for ‘short term (less than 200 years) periodic,’ and the comet orbits the Sun once every 6.44 years. Perihelion for 67/P occurs on August 13th, 2015 when the comet reaches a distance of 1.24 AU ( 191 million kilometres) from the Sun.
Discovered in 1969 by the Kiev University’s Klim Ivanovych Churyumov while examining a photograph taken by Svetlana Gerasimenko, this is the comet’s seventh apparition. Currently shining at +18th magnitude in the constellation Aquarius, Comet 67P C-G will vault up in the early morning sky for northern hemisphere observers and cross the ecliptic plane in the last week of July, at 43 degrees elongation west of the Sun.
The comet is expected to reach a maximum brightness of +11th magnitude near perihelion. Historically, 67P – like most comets – tend to under-perform before perihelion, only to have an energetic lingering outburst phase post-perihelion.
“With each apparition we see it (67P) behave differently.” Yanamandra-Fisher said. “These legacy data sets will aid in our knowledge of this comet, especially when used in combination with the data gathered by the Rosetta spacecraft and the new ground observations made this year.”
The path of 67/P through the morning sky as seen from latitude 30 degrees north. Image credit: Starry Night Education software
Time on professional scopes is always chronically in short supply, with more astronomers and targets to observe than there are telescopes available. That’s where amateur observers come in. Many private backyard observatories have instruments that would be the envy of many a major institution. Though the press release suggests that the minimum aperture size needed to observe 67P this summer is 14-inches (35 cm), we urge 10” or 12” inch scope owners – especially those who have the latest generation of Mallincam and faint object CCD imagers – to give it a try. We’ve seen some amazing results with these, even during quick casual observing sessions such as public star parties! The Rosetta team is looking for everything from professional grade images, to sketches and visual observations with magnitude estimations.
Of course, hunting faint comets is a daunting task at best. +10th magnitude is generally our cut-off for ‘is interesting enough to alert the public’ in terms of novae or comets, though we’ll let 67/P ‘into the club’ due to its celebrity status.
To add to the challenge, the comet is only visible against a dark sky during a brief pre-dawn window. You’ll need a planetarium program (we use Starry Night Pro) to generate good finder charts down to 15th magnitude or so. Keep in mind, comets also typically appear a bit fainter visually than stars of the same magnitude due to the fact that said brightness is spread out over a broad surface area.
“This is truly interactive science that people of all observing levels can participate in- from amateurs to professionals.” Yanamandra-Fischer said in closing.
Other comets to watch for in 2015 include still bright 2014 Q2 Lovejoy, C/2013 US10 Catalina, C/2014 Q1 PanSTARRS, and 19P/Borrelly.
What’ll happen as 67P approaches perihelion? Will those two gigantic lobes crack and separate as Rosetta and the world looks on? Now, I’d pay to see that!
A light bucket scope at the Bruneau Dunes observatory suitable for a faint comet quest. Image credit: David Dickinson
Nothing lasts forever, not even black holes. According to Stephen Hawking, black holes will evaporate over vast periods of time. But how, exactly, does this happen?
The actor Stephen Hawking is best known for his cameo appearances in Futurama and Star Trek, you might surprised to learn that he’s also a theoretical astrophysicist. Is there anything that guy can’t do?
One of the most fascinating theories he came up with is that black holes, the Universe’s swiffer, can actually evaporate over vast periods of time.
Quantum theory suggests there are virtual particles popping in and out of existence all the time. When this happens, a particle and its antiparticle appear, and then they recombine and disappear again.
When this takes place near an event horizon, strange things can happen. Instead of the two particles existing for a moment and then annihilating each other, one particle can fall into the black hole, and the other particle can fly off into space. Over vast periods of time, the theory says that this trickle of escaping particles causes the black hole to evaporate.
Wait, if these virtual particles are falling into the black hole, shouldn’t that make it grow more massive? How does that cause it to evaporate? If I add pebbles to a rock pile, doesn’t my rock pile just get bigger?
It comes down to perspective. From an outside observer watching the black hole’s event horizon, it appears as if there’s a glow of radiation coming from the black hole. If that was all that was happening, it would violate the law of thermodynamics, as energy can neither be created nor destroyed. Since the black hole is now emitting energy, it needs to have given up a little bit of its mass to provide it.
Let’s try another way to think about this. A black hole has a temperature. The more massive it is, the lower its temperature, although it’s still not zero.
From now and until far off into the future, the temperature of the largest black holes will be colder than the background temperature of the Universe itself. Light from the cosmic microwave background radiation will fall in, increasing its mass.
Viewed in visible light, Markarian 739 resembles a smiling face. Inside are two supermassive black holes, separated by about 11,000 light-years. The galaxy is 425 million light-years away from Earth. Credit: Sloan Digital Sky Survey
Now, fast forward to when the background temperature of the Universe drops below even the coolest black holes. Then they’ll slowly radiate heat away, which must come from the black hole converting its mass into energy.
The rate that this happens depends on the mass. For stellar mass black holes, it might take 10^67 years to evaporate completely.
For the big daddy supermassive ones at the cores of galaxies, you’re looking at 10^100. That’s a one, followed by 100 zero years. That’s huge number, but just like any gigantic and finite number, it’s still less than infinity. So over an incomprehensible amount of time, even the longest living objects in the Universe – our mighty black holes – will fade away into energy.
One last thing, the Large Hadron Collider might be capable of generating microscopic black holes, which would last for a fraction of a second and disappear in a burst of Hawking radiation. If they find them, then Hawking might want to the acting on hold and focus on physics.
The LHC. Image Credit: CERN
Nothing is eternal, not even black holes. Over the longest time frames we’re pretty sure they’ll evaporate away into nothing. The only way to find out is to sit back and watch, well maybe it’s not the only way.
Does the idea of these celestial nightmares evaporating fill you with existential sadness? Feel free to share your thoughts with others in the comments below.
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Light makes life, and sometimes, life returns the favor. There’s nothing more magical than watching fireflies flit across a starlit field on a summer’s night. Growing up in Northern Maine, summer was an all-too swiftly passing season, and fireflies had to put on their displays in a brief profusion of frenzied activity around late July and early August before the weather turned once again towards another long harsh winter.
Fireflies remind us of the ephemeral nature of existence, that’s for sure. And they’re much more welcome by summertime campers on vigil for the August Perseids than oh, say the ubiquitous mosquito or vicious black flies…
A recent amazing capture (see the intro image) came to us courtesy of Steed Yu. Shooting from the shores of Lake Natron in Tanzania, he managed to capture an amazing composition of fireflies and those ‘fireflies of the cosmos,’ in the form of a star-dappled southern hemisphere sky.
Taken on February 24th 2015 just south of the equator, this is simply an amazing image. Don’t forget, though it’s towards the end winter time up here in the northern hemisphere in late February, it’s the tail end of the summer south of the equator.
The photographer had this to say about his ‘Carnival of Fireflies’:
The Night of Lake Natron belongs to the stars. Without any artificial light disturbing the pure sky, one can easily see the Southern Milky Way, as well as sparkling starlights scattered in it, such as the most distinctive constellation Southern Cross and our nearest stellar neighbours Alpha Centauri. The Night of Lake Natron belongs to the firefly too. These glowing elves were flying up and down among the lush grass on both sides of a ravine stream, like a flowing “Firefly Way”, as if to contest with the Milky Way. On the quiet starry night, the fireflies held a grand carnival.
Fireflies shine through a method known as bioluminescence, producing a cold light via a chemical process using the chemical luciferin that causes their abdomen to glow. This aids mating and mate selection, and even firefly larvae have been known to glow. Other deep sea and cave-dwelling species of fish and insects have been known to use a similar signaling method in the absence of ambient light.
You can see the stars of the southern Milky Way and the Southern Cross high above the African night shining in their own particular fashion via nuclear fusion, using the proton-proton chain reaction to shed their ancient photons of light onto the nighttime scene from beyond the cold dust lanes of the Coal Sack.
We’ve managed to observe the sky from the southern hemisphere five times from three different continents over the years, and can attest that all of the ‘good stuff’ is in the southern sky, where the core of our home Milky Way galaxy arcs high overhead.
Such ‘Firefly Time-lapse Astronomy’ is as easy as parking a DSLR with a wide-field of view lens on a tripod and shooting 10-60 second time exposures. Fellow Universe Today writer Bob King wrote a piece last year on his firefly astronomy adventures.
And check out this amazing video sequence by Vincent Brady taken in the summer of 2013 from Lake of the Ozarks, Missouri:
Humans have also mastered the art of creating light and luminescence via technology as well. This has served as a way to ‘push back the night,’ and our 24 hour civilization has come to rely on this mimicry of nature as we demonstrate our prowess at illumination. This often has a cost, however, as we banish the beauty of the night sky to a distant memory. We’ve also had the dubious pleasure of observing and conducting impromptu sidewalk star parties from downtown Tampa and the Las Vegas strip, arguably some of the most light-polluted locales in the world. On such nights, only the Moon, planets and perhaps the odd bright double stars are the only viable targets.
Even in light pollution conscious Flagstaff, Arizona, the problem persists. Image credit: Dave Dickinson
But all is not lost. Perhaps wasteful light pollution is only an adolescent phase that civilizations go through. One SETI search strategy has even suggested that we may be able to detect ET via light pollution from alien cities on the night side of prospective planets … perhaps some race of ‘intelligent fireflies’ straight out of science fiction will use bio-chemical signaling for communication?
All great thoughts to ponder on the star-filled summer nights ahead, as fireflies swarm around us. We move that if we ever become an interstellar species that we bring the noble firefly along for the ride… but please, let’s leave light pollution and mosquitoes behind.
Infographic shows how SpaceX Falcon 9 will fly back to Earth after next launch on CRS-6 mission to ISS. Credit: SpaceX
KENNEDY SPACE CENTER, FL – Now just a day away, all systems are “GO” for blastoff of the next SpaceX Falcon 9 rocket carrying the Dragon CRS-6 cargo capsule on Monday, April 13, on a mission to the International Space Station (ISS) and a near simultaneous historic attempt to soft land the boosters first stage on a barge in a remote area of the Atlantic Ocean, hundreds of miles offshore from the US eastern seaboard.
In advance of Mondays launch attempt, SpaceX engineers successfully completed the practice countdown dress rehearsal and required static fire engine test this afternoon, Saturday, April 11, to ensure everything is ready with the rocket and first Stage Merlin 1-D engines for a safe and successful mission to the orbiting outpost.
The Dragon capsule has already been loaded with most of the cargo bound for the space station and was mated to the Falcon 9 booster earlier this week.
Although it is raining heavily now around the Florida Space Coast region along with multiple tornado warning threats, NASA and SpaceX officials are hopeful that weather conditions will clear sufficiently to permit Monday’s planned launch.
U.S. Air Force weather forecasters from the 45th Weather Squadron currently rate the chances of favorable conditions at launch time as 60 percent GO for liftoff of the sixth SpaceX commercial resupply services mission (CRS-6) to the ISS.
Static fire engine test completed on April 11, 2015 in advance of April 13 launch attempt to the International Space Station. Credit: SpaceX
SpaceX and NASA are targeting blastoff of the Falcon 9 and Dragon CRS-6 spacecraft for Monday, April 13, slated at approximately 4:33 p.m. EDT from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida.
NASA Television plans live launch coverage starting at 3:30 p.m EDT: http://www.nasa.gov/multimedia/nasatv/index.html
SpaceX also plans live launch coverage beginning at 4:15pm EDT: www.spacex.com/webcast
The launch window is instantaneous, meaning that the rocket must liftoff at the precisely appointed time. Any delays due to weather or technical factors will force a scrub.
If all goes well with Mondays launch attempt, the Dragon spacecraft will rendezvous with the Earth orbiting outpost Wednesday, April 15, after a two day orbital chase.
In the event of a scrub for any reason, the backup launch day is 24 hours later on Tuesday, April 14, at approximately 4:10 p.m.
The Falcon 9 first stage is outfitted with four landing legs and grid fins to enable the landing attempt, which is a secondary objective of SpaceX. Cargo delivery to the station is the overriding primary objective and the entire reason for the CRS-6 mission.
The SpaceX plan is to direct the spent 1st stage on a precision guided rocket assisted descent from high altitude to accomplish a pinpoint soft landing onto a tiny platform in the middle of a vast ocean.
The ocean-going barge is known as the ‘autonomous spaceport drone ship’ (ASDS). It is being positioned some 200 to 250 miles offshore of the Carolina’s in the Atlantic Ocean along the rockets flight path flying along the US Northeast coast to match that of the ISS.
The ASDS measures only 300 by 100 feet, with wings that extend its width to 170 feet.
A SpaceX Falcon 9 rocket and Dragon cargo ship are set to liftoff on a resupply mission to the International Space Station (ISS) from launch pad 40 at Cape Canaveral, Florida. File photo. Credit: Ken Kremer – kenkremer.com
This marks the 2nd attempt by SpaceX to recovery the 14 story tall Falcon 9 first stage booster on the ASDS barge.
The first attempt in January during the CRS-5 mission was largely successful, as I wrote earlier at Universe Today, despite making a ‘hard landing’ on the ASDS. The booster did make it to the drone ship, positioned some 200 miles offshore of the Florida-Carolina coast, northeast of the launch site in the Atlantic Ocean. The rocket broke into pieces upon hitting the barge.
Overall CRS-6 is the sixth SpaceX commercial resupply services mission and the seventh trip by a Dragon spacecraft to the station since 2012.
CRS-6 marks the company’s sixth operational resupply mission to the ISS under a $1.6 Billion contract with NASA to deliver 20,000 kg (44,000 pounds) of cargo to the station during a dozen Dragon cargo spacecraft flights through 2016 under NASA’s original Commercial Resupply Services (CRS) contract.
Dragon is packed with more than 4,300 pounds (1915 kilograms) of scientific experiments, technology demonstrations, crew supplies, spare parts, food, water, clothing and assorted research gear for the six person Expedition 43 and 44 crews serving aboard the ISS.
Dragon cargo vessel ready for mating to SpaceX Falcon 9 rocket for CRS-6 mission launch to the International Space Station (ISS) scheduled for April 13, 2015. Credit: SpaceX
The ship will remain berthed at the ISS for about five weeks.
The ISS cannot function without regular deliveries of fresh cargo by station partners from Earth.
Watch for Ken’s continuing onsite coverage of the CRS-6 launch from the Kennedy Space Center and Cape Canaveral Air Force Station.
Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.
Dragon cargo vessel being mated to SpaceX Falcon 9 rocket for CRS-6 mission launch to the International Space Station (ISS) scheduled for April 13, 2015. Credit: SpaceX
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Learn more about SpaceX, Mars rovers, Orion, Antares, MMS, NASA missions and more at Ken’s upcoming outreach events:
Apr 11-13: “SpaceX, Orion, Commercial crew, Curiosity explores Mars, MMS, Antares and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings
Apr 18/19: “Curiosity explores Mars” and “NASA Human Spaceflight programs” – NEAF (NorthEast Astronomy Forum), 9 AM to 5 PM, Suffern, NY, Rockland Community College and Rockland Astronomy Club
Seasonal flows spotted by HiRISE on northwestern slopes in Hale Crater. (NASA/JPL/University of Arizona)
As the midsummer Sun beats down on the southern mountains of Mars, bringing daytime temperatures soaring up to a balmy 25ºC (77ºF), some of their slopes become darkened with long, rusty stains that may be the result of water seeping out from just below the surface.
The image above, captured by the HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter on Feb. 20, shows mountain peaks within the 150-km (93-mile) -wide Hale Crater. Made from data acquired in visible and near infrared wavelengths the long stains are very evident, running down steep slopes below the rocky cliffs.
These dark lines, called recurring slope lineae (RSL) by planetary scientists, are some of the best visual evidence we have of liquid water existing on Mars today – although if RSL are the result of water it’s nothing you’d want to fill your astro-canteen with; based on the first appearances of these features in early Martian spring any water responsible for them would have to be extremely high in salt content.
According to HiRISE Principal Investigator Alfred McEwen “[t]he RSL in Hale have an unusually “reddish” color compared to most RSL, perhaps due to oxidized iron compounds, like rust.”
See a full image scan of the region here, and watch an animation of RSL evolution (in another location) over the course of a Martian season here.
Perspective view of Hale crater made from data acquired by ESA’s Mars Express. Credit: ESA/DLR/FU Berlin (G. Neukum)THEMIS image of channels in the southeastern ejecta of Hale crater. Credit: NASA/JPL-Caltech/Arizona State University. (Source.)
Hale Crater itself is likely no stranger to liquid water. Its geology strongly suggests the presence of water at the time of its formation at least 3.5 billion years ago in the form of subsurface ice (with more potentially supplied by its cosmic progenitor) that was melted en masse at the time of impact. Today carved channels and gullies branch within and around the Hale region, evidence of enormous amounts of water that must have flowed from the site after the crater was created. (Source.)
The crater is named after George Ellery Hale, an astronomer from Chicago who determined in 1908 that sunspots are the result of magnetic activity.
UPDATE April 13: Conditions for subsurface salt water (i.e., brine) have also been found to exist in Gale Crater based on data acquired by the Curiosity rover. Gale was not thought to be in a location conducive to brine formation, but if it is then it would further strengthen the case for such salt water deposits in places where RSL have been observed. Read more here.
Apollo 13 images via NASA. Montage by Judy Schmidt.
To celebrate the 45th anniversary of the Apollo 13 mission, Universe Today is featuring “13 MORE Things That Saved Apollo 13,” discussing different turning points of the mission with NASA engineer Jerry Woodfill.
Very quickly after the explosion of Oxygen Tank 2 in Apollo 13’s service module, it became apparent the Odyssey command module was dying. The fuel cells that created power for the Command Module were not working without the oxygen. But over in the Aquarius lunar lander, all the systems were working perfectly. It didn’t take long for Mission Control and the crew to realize the Lunar Module could be used as a lifeboat.
The crew quickly powered up the LM and transferred computer information from Odyssey to Aquarius. But as soon as they brought the LM communications system on line another problem developed.
The Apollo 13 crew couldn’t hear Mission Control.
Screenshot from Apollo footage of Jim Lovell and Jack Swigert. Credit: NASA
The crew radioed they were getting lots of background static, and at times, they reported communications from the ground were “unreadable.”
Additionally, the Manned Space Flight Network (MSFN) tracking stations around the world were having trouble “hearing” the Apollo 13 spacecraft’s radio broadcasting the tracking data.
“Without reliable knowledge of where the vehicle was or was going might result in disaster,” said NASA engineer Jerry Woodfill.
What was going on?
The dilemma was that two radio systems were using the same frequency. One was the transmitter from the LM’s S-band antenna. The other was the broadcast from the spent third stage of the Saturn V, known as the S-IVB.
The seismic station at the Apollo 12 site. The seismometer monitors the level of ground motion to detect arriving seismic waves. The instrument (left) is protected by metal foil against the varying temperatures on the lunar surface that produce large thermal stresses . Credit: NASA
As part of a science experiment, NASA had planned for crashing Apollo 13’s S-IVB into the Moon’s surface. The Apollo 12 mission had left a seismometer on the Moon, and an impact could produce seismic waves that could be registered for hours on these seismometers. This would help scientist to better understand the structure of the Moon’s deep interior.
In Apollo 13’s nominal flight plan, the lander’s communications system would only be turned on once the crew began preparing for the lunar landing. This would have occurred well after the S-IVB had crashed into the Moon. But after the explosion, the flight plan changed dramatically.
The flight profile of an Apollo mission to the Moon, distances not to scale. Note the Saturn V 3rd stage flight path. Credit: NASA.
But with both the Saturn IVB and the LM’s transmitters on the same frequency, it was like having two radio stations on the same spot on the dial. Communications systems on both ends were having trouble locking onto the correct signal, and instead were getting static or no signal at all.
The Manned Space Flight Network (MSFN) for the Apollo missions had three 85 foot (26 meter) antennas equally spaced around the world at Goldstone, California, Honeysuckle Creek, Australia and Fresnedillas (near Madrid), Spain.
According to historian Hamish Lindsay at Honeysuckle Creek, there was initial confusion. The technicians at the tracking sites immediately knew what the problem was and how they could fix it, but Mission Control wanted them to try something else.
“The Flight Controllers at Houston wanted us to move the signal from the Lunar Module across to the other side of the Saturn IVB signal to allow for expected doppler changes,” Hamish quoted Bill Wood at the Goldstone Tracking Station. ”Tom Jonas, our receiver-exciter engineer, yelled at me, ‘that’s not going to work! We will end up locking both spacecraft to one up-link and wipe out the telemetry and voice contact with the crew.’”
At that point, without the correct action, Houston lost telemetry with the Saturn IVB and voice contact with the spacecraft crew.
But luckily, the big 64 meter Mars antenna at Goldstone was already being switched over to help with the Apollo emergency and “their narrower beam width managed to discriminate between the two signals and the telemetry and voice links were restored,” said Wood.
That stabilized the communications. But then it was soon time to switch to the tracking station at Honeysuckle Creek.
The Honeysuckle antenna by night. Photo by Hamish Lindsay.
There, Honeysuckle Creek Deputy Director Mike Dinn and John Mitchell, Honeysuckle Shift Supervisor were ready. Both had foreseen a potential problem with the two overlapping frequency systems and before the mission had discussed it with technicians at Goddard Spaceflight Center about what they should do if there was a communication problem of this sort.
When Dinn had been looking for emergency procedures, Mitchell had proposed the theory of getting the LM to switch off and then back on again. Although nothing had been written down, when the emergency arose, Dinn knew what they had to do.
“I advised Houston that the only way out of this mess was to ask the astronauts in the LM to turn off its signal so we could lock on to the Saturn IVB, then turn the LM back on and pull it away from the Saturn signal,” said Dinn.
It took an hour for Mission Control in Houston to agree to the procedure.
“They came back in an hour and told us to go ahead,” said Mitchell, “and Houston transmitted the instructions up to the astronauts ‘in the blind’ hoping the astronauts could hear, as we couldn’t hear them at that moment. The downlink from the spacecraft suddenly disappeared, so we knew they got the message. When we could see the Saturn IV downlink go way out to the prescribed frequency, we put the second uplink on, acquired the LM, put the sidebands on, locked up and tuned away from the Saturn IVB. Then everything worked fine.”
Dinn said they were able to “pull” the frequencies apart by tuning the station transmitters appropriately.
Technicians at the Honeysuckle Creek tracking station near Canberra, Australia work to maintain communications with Apollo 13. Credit: Hamish Lindsay.
This action, said Jerry Woodfill, was just one more thing that saved Apollo 13.
“The booster stage’s radio was de-turned sufficiently from the frequency of the LM S-Band so that the NASA Earth Stations recognized the signal required to monitor Apollo 13’s orbit at lunar distances,” explained Woodfill. “This was altogether essential for navigating and monitoring the crucial mid-course correction burn which restored the free-return trajectory as well as the set-up of the subsequent PC+2 burn to speed the trip home needed to conserve water, oxygen and water stores to sustain the crew.”
You can hear some of the garbled communications and Mission Control issuing instructions how to potentially deal with the problem at this link from Honeysuckle Creek’s website.
As for the S-IVB science experiment, the 3rd stage crashed successfully on the Moon, providing some of the first data for understanding the Moon’s interior.
Later, on hearing that the stage had hit the Moon, Apollo 13 Commander Jim Lovell said, “Well, at least one thing worked on this mission!”
(Actually, in spite of the Apollo 13 accident, a total of four science experiments were successfully conducted on Apollo 13.)
In early 2010, NASA’s Lunar Reconnaissance Orbiter spacecraft imaged the crater left by the Apollo 13 S-IVB impact.
On April 14th 1970, the Apollo 13 Saturn IVB upper stage impacted the moon north of Mare Cognitum, at -2.55° latitude, -27.88° East longitude. The impact crater, which is roughly 30 meters in diameter, is clearly visible in the Lunar Reconnaissance Orbiter Camera’s (LROC) Narrow Angle Camera image. Credit: NASA/Goddard/Arizona State University.
Thanks to space historian Colin Mackellar from the Honeysuckle Creek website, along with technician Hamish Lindsay and his excellent account of the Honeysuckle Creek Tracking station and their role in the Apollo 13 mission.
When a massive star reaches the end of its life, it can explode as a supernova. How quickly does this process happen?
Our Sun will die a slow sad death, billions of years from now when it runs out of magic sunjuice. Sure, it’ll be a dramatic red giant for a bit, but then it’ll settle down as a white dwarf. Build a picket fence, relax on the porch with some refreshing sunjuice lemonade. Gently drifting into its twilight years, and slowly cooling down until it becomes the background temperature of the Universe.
If our Sun had less mass, it would suffer an even slower fate. So then, unsurprisingly, if it had more mass it would die more quickly. In fact, stars with several times the mass of our Sun will die as a supernova, exploding in an instant. Often we talk about things that take billions of years to happen on the Guide to Space. So what about a supernova? Any guesses on how fast that happens?
There are actually several different kinds of supernovae out there, and they have different mechanisms and different durations. But I’m going to focus on a core collapse supernova, the “regular unleaded” of supernovae. Stars between 8 and about 50 times the mass of the Sun exhaust the hydrogen fuel in their cores quickly, in few short million years.
Just like our Sun, they convert hydrogen into helium through fusion, releasing a tremendous amounts of energy which pushes against the star’s gravity trying to collapse in on itself. Once the massive star runs out of hydrogen in its core, it switches to helium, then carbon, then neon, all the way up the periodic table of elements until it reaches iron. The problem is that iron doesn’t produce energy through the fusion process, so there’s nothing holding back the mass of the star from collapsing inward.
… and boom, supernova.
The outer edges of the core collapse inward at 70,000 meters per second, about 23% the speed of light. In just a quarter of a second, infalling material bounces off the iron core of the star, creating a shockwave of matter propagating outward. This shockwave can take a couple of hours to reach the surface.
SN 1987A, an example of a Type II-P Supernova
As the wave passes through, it creates exotic new elements the original star could never form in its core. And this is where we get all get rich. All gold, silver, platinum, uranium and anything higher than iron on the periodic table of elements are created here. A supernova will then take a few months to reach its brightest point, potentially putting out as much energy as the rest of its galaxy combined.
Supernova 1987A, named to commemorate the induction of the first woman into the Rock and Roll Hall of Fame, the amazing Aretha Franklin. Well, actually, that’s not true, it was the first supernova we saw in 1987. But we should really name supernovae after things like that. Still, 1987A went off relatively nearby, and took 85 days to reach its peak brightness. Slowly declining over the next 2 years. Powerful telescopes like the Hubble Space Telescope can still see the shockwave expanding in space, decades later.
Evolution of a Type Ia supernova. Credit: NASA/CXC/M. Weiss
Our “regular flavor” core collapse supernova is just one type of exploding star. The type 1a supernovae are created when a white dwarf star sucks material off a binary partner like a gigantic parasitic twin, until it reaches 1.4 times the mass of the Sun, and then it explodes. In just a few days, these supernovae peak and fade much more rapidly than our core collapse friends.
So, how long does a supernova take to explode? A few million years for the star to die, less than a quarter of a second for its core to collapse, a few hours for the shockwave to reach the surface of the star, a few months to brighten, and then just few years to fade away.
Which star would you like to explode? Tell us in the comments below.
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