A newly found asteroid, 2013 EC can be seen in the lower left corner of the red box in this image. Screen capture from Virtual Telescope webcast on 3/3/2013.
A newly found asteroid will pass just inside the orbit of the Moon, with its closest approach on March 4, 2013 at 07:35 UTC. Named 2013 EC, the asteroid is about the size of the space rock that exploded over Russia two and a half weeks ago, somewhere between 10-17 meters wide. The asteroid that sparked the Russian meteor is estimated to have been about 17 meters wide when it entered Earth’s atmosphere.
2013 EC was discovered by the Mt. Lemmon Observatory in Arizona on March 2. There is no chance this asteroid will hit Earth.
2013 EC will come within 396,000 kilometers from Earth, (246,000 miles, or around 1.0 lunar distances, 0.0026 AU.
The Moon’s distance from the Earth varies between 363,104 km (225,622 miles) at perigee (closest) and 406,696 km (252,088 miles) at apogee (most distant point).
Gianluca Masi from the Virtual Telescope Project had a live view of the asteroid when it was about twice the distance of the Moon, and a replay of that webcast is available below. (Views of the asteroid start at about 31:00 in the video.)
“That we are finding all these asteroids recently does not mean that we are being visited by more asteroids,” Masi said during the webcast, “just that our ability to detect them has gotten so much better. Our technology has improved a lot over the past decades.”
SpaceX Dragon berthing at ISS on March 3, 2013. Credit: NASA
Kennedy Space Center – After overcoming a frightening thruster failure that could have spelled rapid doom on the heels of a breathtakingly beautiful launch, the privately developed Dragon spacecraft successfully berthed at the International Space Station (ISS) a short while ago, at 8:56 a.m. EST Sunday morning, March 3, 2013 – thereby establishing an indispensable American Lifeline to the massive orbiting lab complex.
Hearts sank and hopes rose in the span of a few troubling hours following Friday’s (Mar. 1) flawless launch of the Dragon cargo resupply capsule atop the 15 story tall Falcon 9 rocket from Cape Canaveral Air Force Station, Florida and the initial failure of the life giving solar arrays to deploy and failure of the maneuvering thrusters to fire.
“Congrats to the @NASA/@SpaceX team. Great work getting #Dragon to the #ISS…our foothold for future exploration!” tweeted NASA Deputy Administrator Lori Garver.
Space station Expedition 34 crew members Kevin Ford and Tom Marshburn of NASA used the station’s 58 foot long Canadian supplied robotic arm to successfully grapple and capture Dragon at 5:31 a.m. Sunday as the station was flying 253 miles above northern Ukraine. See the grappling video – here.
SpaceX Dragon holding at 10m capture point. ISS crew standing by for “go” to perform grapple. Credit: NASA
“The vehicle’s beautiful, space is beautiful, and the Canadarm2 is beautiful too”, said station commander Kevin Ford during the operation.
The capsule pluck from free space came one day, 19 hours and 22 minutes after the mission’s launch.
Ground controllers at NASA’s Johnson Space Center in Houston then commanded the arm to install Dragon onto the Earth-facing port of the Harmony module – see schematic.
Schematic shows location of Dragon docking port for CRS-2 mission and ISS modules. Credit: NASA
Originally, Dragon capture was slated only about 20 hours after launch. But that all went out the window following the serious post-launch anomalies that sent SpaceX engineers desperately scrambling to save the flight from a catastrophic finale.
The $133 million mission dubbed CRS-2 is only the 2nd contracted commercial resupply mission ever to berth at the ISS under NASA’s Commercial Resupply Services (CRS) contract. The contract is worth $1.6 Billion for at least a dozen resupply flights.
Following the forced retirement of NASA’s space shuttle orbiters in July 2011, American was left with zero capability to launch either cargo or astronauts to the primarily American ISS. NASA astronauts are 100% reliant on Russian Soyuz capsules for launch to the ISS.
Both the Falcon 9 rocket and Dragon spacecraft were designed and built by SpaceX Corporation based in Hawthorne, Calif., and are entirely American built.
The Falcon 9/Dragon commercial system restores America’s unmanned cargo resupply capability. But the time gap will be at least 3 to 5 years before American’s can again launch to the ISS aboard American rockets from American soil.
And continuing, relentless cuts to NASA’s budget are significantly increasing that human spaceflight gap and consequently forces more payments to Russia.
“Today we marked another milestone in our aggressive efforts to make sure American companies are launching resupply missions from U.S. shores,” said NASA Admisistrator Charles Bolden in a NASA statement.
“Our NASA-SpaceX team completed another successful berthing of the SpaceX Dragon cargo module to the International Space Station (ISS) following its near flawless launch on the Falcon-9 booster out of Cape Canaveral, Florida Friday morning. Launching rockets is difficult, and while the team faced some technical challenges after Dragon separation from the launch vehicle, they called upon their thorough knowledge of their systems to successfully troubleshoot and fully recover all vehicle capabilities. Dragon is now once again safely berthed to the station.”
“I was pleased to watch the launch from SpaceX’s facility in Hawthorne, CA, and I want to congratulate the SpaceX and NASA teams, who are working side by side to ensure America continues to lead the world in space.”
“Unfortunately, all of this progress could be jeopardized with the sequestration ordered by law to be signed by the President Friday evening. The sequester could further delay the restarting of human space launches from U.S. soil, push back our next generation space vehicles, hold up development of new space technologies, and jeopardize our space-based, Earth observing capabilities,” said Bolden.
ISS crew given GO for second stage capture of SpaceX Dragon with ISS on March 3, 2013. Credit: NASA
Dragon is loaded with about 1,268 pounds (575 kilograms) of vital supplies and provisions to support the ongoing science research by the resident six man crew, including more than a ton of vital supplies, science gear, research experiments, spare parts, food, water and clothing.
NASA says that despite the one-day docking delay, the Dragon unberthing will still be the same day as originally planned on March 25 – followed by a parachute assisted splashdown in the Pacific Ocean off the coast of Baja California.
Dragon will spend 22 days docked to the ISS. The station crew will soon open the hatch and unload all the up mass cargo and research supplies. Then they will pack the Dragon with about 2,668 pounds (1,210 kilograms) of science samples from human research, biology and biotechnology studies, physical science investigations, and education activities for return to Earth.
Canadian built robotic arm grapples SpaceX Dragon on March 3, 2013. Credit:
Dragon is the only spacecraft in the world today capable of returning significant amounts of cargo to Earth.
Orbital Sciences Corp also won a $1.9 Billion cargo resupply contract from NASA to deliver cargo to the ISS using the firm’s new Antares rocket and Cygnus capsule.
NASA hopes the first Antares/Cygnus demonstration test flight from NASA’s Wallops Island Facility in Virginia will follow in April. Cygnus cargo transport is one way – to orbit only.
“SpaceX is proud to execute this important work for NASA, and we’re thrilled to bring this capability back to the United States,” said Gwynne Shotwell, President of SpaceX.
“Today’s launch continues SpaceX’s long-term partnership with NASA to provide reliable, safe transport of cargo to and from the station, enabling beneficial research and advancements in technology and research.”
The SpaceX CRS-3 flight is slated to blast off in September 2013.
The Dragon approaches the ISS over sub-Saharan Africa. Credit: NASA/Chris Hadfield.
SpaceX’s Dragon spacecraft has arrived at the International Space Station! After overcoming a problem with its thrusters after reaching orbit on on Friday, today, Dragon successfully approached the Station, where it was captured by Expedition 34 Commander Kevin Ford and crewmate Tom Marshburn using the station’s Canadarm2 robotic arm. Dragon was grappled at 5:31 a.m. EST, and was berthed to the Earth-facing port of the Harmony module at approximately 8:56 a.m. EST on March 3.
Below, Canadian astronaut Chris Hadfield snapped a photo of Dragon as it approached the station over sub-Saharan Africa. “A surreal juxtaposition,” Hadfied said via Twitter.
Launch of SpaceX Falcon 9 on CRS-2 mission on March 1, 2013 from Cape Canaveral, Florida. Credit: Jeff Seibert
Kennedy Space Center – Barely 11 minutes after the spectacular Friday morning, March 1 launch of the SpaceX Falcon 9 rocket and unmanned Dragon capsule bound for the International Space Station (ISS), absolute glee suddenly threatened to turn to total gloom when the mission suffered an unexpected failure in the critical propulsion system required to propel the Dragon to the Earth orbiting outpost.
An alarming issue with the Dragons thrust pods prevented three out of four from initializing and firing.
For several hours the outlook for the $133 million mission appeared dire, but gradually began to improve a few hours after launch.
“It was a little frightening,” said SpaceX CEO Elon Musk at a Friday afternoon media briefing for reporters gathered at the Kennedy Space Center, commenting on the moments after the glitch appeared out of nowhere.
“We noticed after separation that only one of the four thruster pods engaged or was ready to engage,” Musk explained. “And then we saw that the oxidizer pressure in three of the four tanks was low.”
Launch of SpaceX Falcon 9 on CRS-2 mission on March 1, 2013 from Cape Canaveral, Florida. Credit: Jeff Seibert/Wired4Space.com
The situation progressed onto the road to recovery after SpaceX engineers immediately sprang into action and frantically worked to troubleshoot the thruster problems in an urgent bid to try and bring the crucial propulsion systems back on line and revive the mission.
By late Saturday afternoon sufficient recovery work had been accomplished to warrant NASA, ISS and SpaceX managers to give the go-ahead for the Dragon to rendezvous with the station early Sunday morning, March 3.
“The station’s Mission Management Team unanimously agreed that Dragon’s propulsion system is operating normally along with its other systems and ready to support the rendezvous two days after Friday’s launch on a Falcon 9 rocket from the Cape Canaveral Air Force Station in Florida,” NASA announced in a statement on Saturday, March 2.
A failure to ignite the thrusters within 1 or 2 days would have resulted in unacceptable orbital decay and a quick and unplanned fiery reentry into the earth’s atmosphere, said Musk.
Reentry would cause a total loss of the mission – carrying more than a ton of vital supplies, science gear, research experiments, spare parts, food, water and provisions to orbit for the stations six man crew.
Shortly after the Dragon achieved orbit and separated from the second stage, the solar arrays failed to deploy and the live webcast stopped prematurely.
Falcon 9 SpaceX CRS-2 launch on March 1, 2013 to the ISS – shot from the roof of the Vehicle Assembly Building. Credit: Ken Kremer/www.kenkremer.com
During the course of the Friday afternoon briefing, Musk and NASA officials received continuous updates indicating the situating was changing and slowly improving.
Musk confirmed that SpaceX was able to bring all four of Dragon’s thruster pods back up and running. Engineers were able to identify and correct the issue, normalizing the pressure in the oxidation tanks.
The problem may have been caused by stuck valves or frozen oxidizer in the lines. Dragon has four oxidizer tanks and four fuel tanks.
“We think there may have been a blockage of some kind or stuck check valves going from the helium pressure tank to the oxidizer tank,” Musk hypothesized. “Whatever that blockage is seems to have alleviated.”
Three of the four thruster pods must be active before the Dragon would be permitted to dock, said Mike Suffredini, NASA program manager for the ISS. There are a total of 18 Draco thrusters.
SpaceX and the ISS partners conducted a thorough review process to assure that the thrusters will work as advertised and allow the Dragon to safely enter the stations keep out zone and physically dock at the berthing port onto the Earth-facing port of the Harmony module.
“SpaceX said it has high confidence there will be no repeat of the thruster problem during rendezvous, including its capability to perform an abort, should that be required,” NASA said in a statement.
Dragon is now slated to be grappled early Sunday morning at 6:31 a.m. by NASA Expedition 34 Commander Kevin Ford and NASA Flight Engineer Tom Marshburn – that’s one day past the originally planned Saturday morning docking.
Video: Falcon 9 SpaceX CRS-2 launch on March 1, 2013 bound for the ISS – shot from the roof of the Vehicle Assembly Building. Credit: Matthew Travis/Spacearium
NASA says that despite the one-day docking delay, the Dragon unberthing and parachute assisted return to Earth will still be the same day as originally planned on March 25.
There are numerous docking opportunities available in the coming days if SpaceX and NASA determined that more time was needed to gain confidence that Dragon could safely carry out an attempt.
Musk said the Dragon could stay on orbit for several additional months if needed.
We have to review the data with NASA before docking to make sure it’s safe, Musk emphasized on Friday.
Falcon 9 SpaceX CRS-2 launch on March 1, 2013. Credit: Mike Killian/www.zerognews.com
The mission dubbed CRS-2 will be only the 2nd commercial resupply mission ever to berth at the ISS. SpaceX is under contract to NASA to conduct a dozen Dragon resupply flight to the ISS over the next few years at a cost of about $1.6 Billion.
NASA TV coverage of rendezvous and grapple on Sunday, March 3 will begin at 3:30 a.m. EST. Coverage of berthing operations on NASA TV will begin at 8 a.m.
SpaceX’s live coverage at http://www.spacex.com/webcast begins at 6:00 a.m. Eastern.
Enhanced-color HiRISE image of impact craters from MSL's ballast weights (NASA/JPL-Caltech)
During its “seven minutes of terror” landing on August 6, 2012, NASA’s Mars Science Laboratory dropped quite a few things down onto the Martian surface: pieces from the cruise stage, a heat shield, a parachute, the entry capsule’s backshell, a sky crane, one carefully-placed rover (obviously) and also eight tungsten masses — weights used for ballast and orientation during the descent process.
Two 75 kilogram (165 lb) blocks were released near the top of the atmosphere and six 25 kg (55 lb) weights a bit farther down, just before the deployment of the parachute. The image above, an enhanced-color image from the HiRISE camera aboard the Mars Reconnaissance Orbiter, shows the impact craters from four of these smaller tungsten masses in high resolution. This is part of a surface scan acquired on Jan. 29, 2013.
These four craters are part of a chain of six from all the 55 kg weights. See below for context:
CLICK TO PLAY – Before-and-after images of the 55 kg-mass landing sites (NASA/JPL/MSSS)
Captured by MRO’s Context Camera shortly after the rover landed, the animation above shows the impact site of all six 55 kg masses. These impacted the Martian surface about 12 km (7.5 miles) from the Curiosity rover’s landing site.
A mosaic has been assembled showing potential craters from the larger ballast blocks as well as other, smaller pieces of the cruise stage. Check it out below or download the full 50mb image here.
HiRISE images of MSL’s impact craters (NASA/JPL/University of Arizona)
It’s time for another giveaway. This time we’re giving out 10 copies of the Sun Surveyor App for iOS. This is an app that helps photographers know where the Sun is going to be, to get that perfect mountain photo.
Sun Surveyor calculates Sun and Moon positions, Sun and Moon rise & set times, solar noon, golden hour and blue hour times, moon phases, sun shadow ratios and many other pieces of related information. A 3D Compass, Augmented Reality View and Interactive Map enable use as a visualizer, tracker and predictor of Sun and Moon paths, with many practical uses for photographers & filmmakers, stargazers, solar industry & real estate professionals, architects and others.
Sun Surveyor is available for iOS and Android. But this promotion is open to iOS users only, unfortunately (iOS lets developers give away free copies of their apps, but Google Play doesn’t).
This Giveaway is now closed. Thank you for your interest!
Curiosity Rover's Self Portrait at 'John Klein' Drilling Site, which combines dozens of exposures taken by the rover's Mars Hand Lens Imager (MAHLI) during the 177th Martian day, or sol, of Curiosity's work on Mars (Feb. 3, 2013). Credit: NASA/JPL-Caltech/MSSS
A problem with the memory on the Curiosity rover’s main computer has caused engineers to switch the rover over to a redundant onboard computer. This caused the rover to go into “safe mode,” which was anticipated in the computer switch. And so now over the next few days, the team will be shifting the rover from safe mode to operational status. They are also troubleshooting the condition that affected operations yesterday.
The @MarsCuriosity Twitter feed posted: “Don’t flip out: I just flipped over to my B-side computer while the team looks into an A-side memory issue.”
JPL said the condition is related to a glitch in flash memory linked to the other, now-inactive, computer in response to a memory issue on the computer that had been active.
The intentional swap occurred at about 2:30 a.m. PST on Thursday, Feb. 28.
“We switched computers to get to a standard state from which to begin restoring routine operations,” said Richard Cook. .
Like many spacecraft, Curiosity carries a pair of redundant main computers in order to have a backup available if one fails. Each of the computers, A-side and B-side, also has other redundant subsystems linked to just that computer. Curiosity is now operating on its B-side, as it did during part of the flight from Earth to Mars. It operated on its A-side from before the August 2012 landing through Wednesday.
“While we are resuming operations on the B-side, we are also working to determine the best way to restore the A-side as a viable backup,” said JPL engineer Magdy Bareh, leader of the mission’s anomaly resolution team.
The spacecraft remained in communications at all scheduled communication windows on Wednesday, but it did not send recorded data, only current status information. The status information revealed that the computer had not switched to the usual daily “sleep” mode when planned. Diagnostic work in a testing simulation at JPL indicates the situation involved corrupted memory at an A-side memory location used for addressing memory files.
Scientific investigations by the rover were suspended Wednesday and today. Resumption of science investigations is anticipated within several days. This week, laboratory instruments inside the rover have been analyzing portions of the first sample of rock powder ever collected from the interior of a rock on Mars.
Mount St. Helens shortly after its eruption in 1980. Credit: Landsat
Turn a camera to a location for four decades, and you can see a lot of change. Streets appear or disappear. Trees grow and eventually, die. Houses spring up and slowly decay.
Landsat is the longest-running Earth observation program, with four decades of observations behind it. Today, to celebrate the launch of Landsat 5 on this day in 1984, here are five Landsat images that helped us better understand the Earth and at times, how humans affect its environment.
Mount St. Helens
When Washington State’s Mount St. Helens exploded in May 1980, it killed 57 people and obliterated much of the surrounding countryside. For American volcanologists, however, St. Helens was an easy target to study both up close and with the Landsat satellite. This 1980 image shows the devastated countryside in the weeks after the eruption. Landsat photos from every year since demonstrate how the area has recovered in the past two decades.
3-D Antarctica
A 3-D map of Antarctica using 1,100 images from the Landsat 7 satellite. Credit: Landsat/USGS
That image up there was years in the making. First, scientists collected 1,100 images of Antarctica using the Landsat 7 satellite. That process took three years, between 1999 and 2001. They combined elevation data and field measurements. Next came the painstaking process of stitching it together. It was finally released to the public in 2007. An unexpected benefit? Spying the continent from space allowed scientists to better track Emperor penguins. That brown stain on the image is actually where the penguins were sitting when the pictures were taken.
Rushing to Kuwait’s rescue
Oil well fires burn in Kuwait during the 1991 Persian Gulf War. Credit: Landsat/USGS
As Iraq pulled out from Kuwait during the Persian Gulf War in 1991, Iraqi troops set fire to some 650 oil wells. The environmental devastation was enormous. This Landsat image, among many others, was crucial for Kuwaiti emergency responders to figure out where the fires were burning and how best to approach them.
Landsat’s Van Gogh image
NASA once compared this image of phytoplankton surrounding Gotland to Vincent Van Gogh’s “Starry Night.” Credit: Landsat/USGS
Are those stars and nebulas we see above? Not quite, but NASA points out it does look very similar to the Vincent Van Gogh image “Starry Night.” That 2005 snapshot from Landsat 7 actually shows phytoplankton surrounding the Swedish island of Gotland in the Baltic Sea. The picture was voted the top snapshot by NASA visitors to the “Earth As Art” contest held in 2012.
Shrinking Aral Sea
The Aral Sea has shrunk to half its size in just 40 years. Credit: Landsat/USGS
The series of Landsat images above show just how much of the Aral Sea disappeared between 1977 and 2006. The body of water, located between Uzbekistan (south) and Kazakhstan, used to be the fourth-largest lake in the world. The Soviets tapped into the sea several decades ago to irrigate the surrounding area. While local authorities are working to reverse the damage, the sea is still about half the size it used to be.
There’s more Landsat magic to come in the next few years. The Landsat Data Continuity Mission left Earth last month and will take more pictures of the Earth in even better resolution than its ancestors. Take a look at its launch video below.
Dragon launches on the SpaceX Falcon 9 on March 1, 2013. Credit: John O'Connor/nasatech
Just after 10 am Eastern time, the SpaceX successfully launched their Dragon capsule on a second resupply mission to the International Space Station. The launch, rocket stage and spacecraft separations went perfectly, but the Dragon experienced an anomaly at about the time the solar arrays should have deployed. The SpaceX webcast announced that the spacecraft experienced a problem and then ended the webcast. NASA TV has not offered information either. We’ll provide more information as soon it becomes available.
Update: (10:44 EST) Elon Musk, SpaceX CEO just tweeted: “Issue with Dragon thruster pods. System inhibiting 3 of 4 from initializing. About to inhibit override.” Then minutes later he added, “Holding on solar array deployment until at least two thruster pods are active.”
See below for a continuation of our live-blogging of the Dragon anomaly, as it happened..
Also, here’s the launch video from launch to separation (note, the separation video is spectacular!):
Dragon carries 18 Draco thrusters for attitude control and maneuvering, so there may be an issue with those. Dragon’s thruster problem may be preventing the spacecraft from going into array deploy attitude, thus preventing array deploy.
Only time will tell if this is a software or hardware problem. The SpaceX press kit describes what needs to happen for solar array deploy:
Dragon separates from Falcon 9’s second stage, and seconds later, Dragon will reach its preliminary orbit. It then deploys its solar arrays and begins a carefully choreographed series of Draco thruster firings to reach the space station.
If Dragon can’t make it to the ISS, then it would need to be decided if and how it can return back to Earth on a good trajectory with limited thruster control.
The SpaceX controllers are obviously working to try and resolve the problem.
Update: 11:10 EST An update from NASA TV at about 11:10 am, said that part of response to problem with Dragon may be reorganizing the burn sequences in order for the spacecraft to be able to approach to the ISS. Musk just tweeted: “About to pass over Australia ground station and command inhibit override.”
Update: 11:25 EST: A statement from SpaceX says that “One thruster pod is running. Two are preferred to take the next step which is to deploy the solar arrays. We are working to bring up the other two in order to plan the next series of burns to get to station.”
Update: 11:42 EST: Elon Musk just tweeted: “Thruster pod 3 tank pressure trending positive. Preparing to deploy solar arrays.” That is good news.
Update: 11:50 EST: Another Tweet from Musk, with some short but sweet news: “Solar array deployment successful” That means they were abe to get at least two of the four thruster pods working, per the minimum requirement. Now, to see if the thruster problem causes any issues with getting to the ISS.
Update: 12:05 EST: Elon Musk continues to be the best source of info. He’s just tweeted, “Attempting bring up of thruster pods 2 and 4.”
We’re assuming that means 1 and 3 are already working, since it was going to take at least 2 pods thrusting to enable solar array deploy.
Update: 12:14 EST: The latest statement from SpaceX : “After Dragon achieved orbit, the spacecraft experienced an issue with a propellant valve. One thruster pod is running. We are trying to bring up the remaining three. We did go ahead and get the solar arrays deployed. Once we get at least 2 pods running, we will begin a series of burns to get to station.”
So, they were able to deploy the arrays with just one thruster pod working, and they are now working to get at least one more working. One question to consider is if the spacecraft and arrays were able to be in the right position to gather sunlight and produce power.
Update: 12:42 EST: According to reports on Twitter, a NASA official has said that three Dragon thruster pods are needed to fly to the ISS, and at this point, only one pod is working.
SpaceX CRS-2 Launch on March 1, 2013. Credit: John O’Connor/nasatech
Update: 2:00 EST: This update from SpaceX: “SpaceX is still working through issues in Dragon’s propulsion system. The mission’s first rendezvous burn was delayed at least one orbit to about 2 p.m. EST.” (which is now)….stay tuned for updates. There will be a press conference sometime today, NASA has said, but has not yet set a specific time.
Update: 2:28 EST: NASA says the Dragon capsule Dragon will no longer be able to make its scheduled rendezvous with the station tomorrow. SpaceX indicated the rendezvous with the ISS will now not happen until at least Sunday morning. There will be a news briefing at 3pm EST.
Communication between the ISS crew and mission control confirms the delay for the rendezvous: “They are making progress recovering their prop system, but it’s not going to be in time to support the rendezvous and capture for tomorrow,” NASA’s spacecraft communicator told the crew. “So that is not going to happen tomorrow.”
“OK, copy, sounds like another off-duty day for us,” said ISS commander Kevin Ford. “We don’t wish that. We wish it gets fixed and gets up here to us. That’s really awesome they’re working their way through the problems. That’s what it’s all about.”
Update: 2:58 EST: Latest Tweet from Elon Musk has good news: “Pods 1 and 4 now online and thrusters engaged. Dragon transitioned from free drift to active control. Yes!!”
Update: 4:11 EST: Here’s a brief synopsis of the press briefing:
During the press conference, Elon Musk indicated there was a blockage in the helium line leading to the oxidizer pressurization system, or perhaps a stuck valve, and the pressure was not high enough to turn on the thrusters. The engineering team cycled the valves several times, using pressure hammering to loosen up and debris that might be stuck in the valves. And now, the pressure is nominal, with all the oxidizer tanks holding the target pressure on all 4 pods, and so Musk said he is hopeful that all the thrusters will be able to work.
Musk said they decided to deploy Dragon arrays before two thrusters were online because the temperature of the array actuators was dropping rapidly. But they also deployed solar arrays partly to mitigate Dragon’s attitude rotation “like a skater extending arms during a spin,” he said.
Musk mentioned the batteries on board had 12-14 hours of life, so deploying the arrays early was not a question of running out of power, but making sure solar arrays didn’t get so cold that they couldn’t deploy later.
NASA’s Mike Suffredini said that at least 3 of the 4 pods have to be operational in order to make an approach to the ISS.
They will make a decision on when to make the rendezvous when they’ve ascertained if the thrusters are working.
Ken Kremer will provide a more detailed update later.
{End of live blogging}
Diagram of the Dragon capsule. Credit: SpaceX
The Dragon is carrying 544 kilograms (1,200 lbs) of scientific experiments and supplies to the space station, and docking was scheduled for Saturday at 6:30 a.m. ET (1100 GMT). That will likely change.
Dragon’s 18 Draco thrusters permit orbital maneuvering and attitude control. They are mounted on four pods: two of the pods contain five thrusters and the other two contain four thrusters. They are powered by nitrogen tetroxide/monomethylhydrazine, and the thrust is used to control the approach to the ISS, power departure from the ISS, and control Dragon’s attitude upon reentry.
As far as the solar arrays, each array is constructed of four panels. Each array measures 6.4 meters (21 feet). The arrays can draw up to 5,000 watts of power, which is about enough power to light about 85 light bulbs. For launch, the arrays are stowed in the unpressurized trunk of the Dragon and are covered by protective fairings. When the fairings jettison, the automated deployment of the arrays is triggered. On the way back to Earth the trunk is jettison and it, along with the arrays, burn up in the atmosphere.
If the arrays do not deploy, battery life on Dragon is only a few hours 12-14 hours, which would not be enough time to keep it alive until it would reach the ISS. It will be about 20 hours from launch until it approaches the ISS, if the mission continues on its scheduled timeline.
You may recall that during the previous mission to the ISS in October 2012 (the second flight to ISS, but first operational SpaceX resupply flight) one of the rocket’s first stage engines suffered an anomaly, where a combustion chamber ruptured. That engine was shut down, and the other engines fired longer to make up for it. The Dragon cargo made it to the correct orbit and continued on the ISS, but a satellite that was launched to orbit as a secondary payload by the Falcon 9 rocket was sent into the wrong orbit as a result of “a pre-imposed safety check required by NASA,” on October 7, and the ORBCOMM OG2 satellite later deorbited and fell back to Earth.
For this launch, all nine engines appeared to work nominally and all stages separated perfectly.
But obviously the SpaceX team saw the thruster problem immediately, as that’s when the webcast was ended.
A poster with a progression of images from Cape Espichel, Sesimbra in Spain. Left is a wide field starscape, center is Orion's deep sky objects and right is a closeup of M42. Credit and copyright: Miguel Claro.
Here’s an awesome sequence of images from skyscape photographer Miguel Claro. These images were captured from Cape Espichel, Sesimbra, Portugal, about 40 km away from Lisbon. This triple sequence poster contains a beautiful widefield view of the well-known winter constellations visible from the northern hemisphere; then a zoom in to focus on Orion; then Claro zooms in even more to find the Great Orion Nebula M42 and M43.
Claro took a single shot for each image with a DSLR camera, using between 10, 35 and 300 mm. “To do this work I´ve used the incredible Vixen Polarie mounting travel, to avoid the Earth rotation, and a Canon 60Da, a camera sensitive to the infrared/H-alpha wavelengths,” Claro said.
Below is an annotated version of the different objects in the image:
An annotated poster with a progression of images from Cape Espichel, Sesimbra in Portugal. Left is a wide field starscape, center is Orion’s deep sky objects and right is a closeup of M42. Credit and copyright: Miguel Claro.
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