SpaceX Launches Falcon Heavy Rocket on Historic Maiden Voyage
February 6th, 2018Update: Astronomers Spot Musk’s Roadster
Via: Virtual Telescope:
The car was about as bright as magnitude 15.5, requiring a large (more than 16? – 400 mm in diameter) to be seen visually.
Below is a video, obtained with 54 images taken back to back, from 11:12 to 12:15 UT, 8 Feb. 2018.
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Update: Was Roadster Spectacle and Subsequent Final Burn a Demonstration for the Pentagon?
Ok, now we’re getting somewhere. Couple more category ticks: [???] and War.
Via: Robert Walker:
No, it wasn’t left in that orbit which was a temporary holding orbit. Immediately after the launch it was in a temporary orbit with maximum altitude 7,000 km, then five hours later they did a final burn to put it on an interplanetary orbit out to beyond the orbit of Mars. They could have done that right away without going into the orbit at all – but as a requirement for future military launches, apparently they had to prove that their final stage could withstand spending a long time in the Van Allen belts. That’s why they deliberately kept it going through the Van Allen belts over and over for five hours before sending the payload into its interplanetary orbit.
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Update: What Is Powering the Communications Package on the Roadster Payload?
On Live Views of Starman, there’s a video feed from the Roadster hurtling through space. Within a few seconds of watching that with my jaw hanging slack, I wondered, “What’s powering the coms package on that thing?”
At first, I wondered if it was the battery pack from the Roadster itself. But if it’s using the car’s battery, how long would that last at -270C?
I wasn’t able to find anything out about this. Can anyone help me out here?
Update: Email From “A Source That Works At A Rocket Company”
He asked not to be identified, so I’ve removed his name and his employer:
Hi Kevin,
I’d be happy to explain how the Falcon Heavy launch worked and answer any questions you have.
The basic idea of how the batteries don’t freeze is that they are in the sunlight (so long as they’re not in the shadow of the earth), and the whole stage is on what’s called a “barbeque roll” rotation with a period of 1-2 minutes. That roll keeps the sun-facing side of the vehicle from getting too hot, and the space-facing side from getting too cold. Deep space is the temperature of the microwave background radiation, which is 2.7 Kelvin, and the Sun is of course around 5800 K (but it doesn’t take up half the sky, only as much area as the moon approximately). When you time-average those two exposures together, the result is approximately room temperature. This is the same reason that the Earth is also approximately at room temperature
As far as I know, there has never been a rocket 2nd stage which included solar panels; they all run on batteries. So you get a fixed amount of time before the batteries run out. Sputnik 1 had batteries to last something like 4 days. Rocket 2nd stages tend to have batteries good for roughly 3 hours, unless you need to do a longer mission profile such as a direct insertion to geostationary orbit. In that case, it takes the stage about six hours to climb up from low Earth orbit to the geostationary belt which is roughly six Earth radii up (quite far out there!). So for a direct GEO mission, you need to add on extra batteries for the 2nd stage so it can stay alive and do its final burn six hours later. That six hour number is dictated solely by the mass & radius of the Earth, Newton’s gravitational constant, and the rotation rate of the Earth. The characteristics of the rocket have nothing to do with it (unless I suppose you took a faster but less fuel-efficient route by blasting yourself up faster, but nobody does that).
During that six hour coast phase, the vehicle gets to experience a ton of trapped solar particles bouncing around in the Earth’s magnetic field, also known as the Van Allen belts. The radiation levels are much much higher than down in low orbit where for instance the ISS resides, and they are actually also generally higher than the radiation levels once you get up into the operational GEO orbit. The electronics controlling the 2nd stage have to be designed to withstand that onslaught in a way that they don’t have to be designed for for a regular LEO or GTO insertion mission profile.
Just for reference, it doesn’t take all that much power to send down the live video stream you saw yesterday. I haven’t looked up the FCC filings (which are public!), but on some previous missions they have used a 20 watt transmitter operating near 2200 MHz for video. That power level and frequency are quite sufficient even for going further away from the Earth’s surface like they did yesterday; all you need is a bigger dish on the ground to pick it up. Remember, NASA picked up live video from the Moon in 1969 using a 70 meter dish. Probably yesterday SpaceX was using something like a 15 meter dish. They didn’t have to go install it themselves, either, there are plenty of dishes already in existence that are available to rent for missions like this.
Let me know if there’s anything else you’d like explained.
Follow up email:
Also,
“Also, the livestream from the car cut out after about 4 hours 40 minutes. So it probably used up the car’s battery, and or some other battery, to keep itself warm and to send the video stream back to Earth, and that’s all she wrote.”
There are two possible reasons they cut off the video stream. #1, the payload was actually on its way back down so they went out of range of their round stations. I haven’t checked the orbital mechanics to verify whether or not this was a contributing factor. #2, I think they wanted to cut the feed before the (still risky) 3rd ignition of the 2nd stage, in case it went poorly. Interestingly, there were visual sightings from Los Angeles of what turned out to be that 3rd burn, propelling the vehicle on its Earth-escape trajectory.
I suspect they still had enough battery to keep the video downlink going, and assuming they did record that data, perhaps they’ll leak some of it out in the future now that they know the vehicle didn’t fail during that 3rd burn
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Via: space.com:
The first Falcon Heavy rocket built by the private spaceflight company SpaceX soared on its maiden voyage today (Feb. 6) — a historic test flight that also sent a car toward Mars and included two confirmed booster landings.
Billed as the world’s most powerful booster since NASA’s Saturn V, the Falcon Heavy rocket lifted off from Launch Pad 39A here at Kennedy Space Center (KSC) — the same site used by NASA’s Apollo moon missions and space shuttles — at 3:45 p.m. EST (2045GMT).
“I’m really excited about today,” SpaceX CEO Elon Musk told reporters after the launch. “I’m really proud of the SpaceX team. They’ve done an incredible job of creating the most advanced rocket in the world, and the biggest rocket in the world.”
Standing 23 stories tall, the Falcon Heavy rocket is SpaceX’s largest rocket yet. Its first stage is powered by three core boosters based on SpaceX’s Falcon 9 rockets, with 27 engines (nine per booster) firing in unison to produce about 5 million lbs. of thrust (22,819 kilonewtons) at liftoff. While SpaceX hoped all three boosters would return to Earth and land, the center core missed its mark – a minor hiccup in an otherwise successful launch, Musk said.
Satire: FBI Warns Republican Memo Could Undermine Faith In Massive, Unaccountable Government Secret Agencies
February 6th, 2018Via: The Onion:
“If we take away the people’s faith in this shadowy monolith exempt from any consequences, all that’s left is an extensive network of rogue, unelected intelligence officers carrying out extrajudicial missions for a variety of subjective, and occasionally personal, reasons.” At press time, Wray confirmed the massive, unaccountable government secret agencies were unaware of any wrongdoing for violating constitutional rights.
Research Credit: Eileen
EHANG 184 AAV Manned Flight Tests
February 6th, 2018Via: Ehang:
China Deploys Experimental Railgun Aboard Warship
February 5th, 2018Via: news.com.au:
WANT to win a war? Build a better gun. Now China appears to have taken a huge stride ahead of the United States with the first experimental deployment of a new ‘supergun’ aboard a warship.
The first images began circulating on the internet last week.
They showed a Chinese amphibious assault ship — usually used to deploy troops and tanks on a beach — fitted with an enormous cannon on its bows.
Overnight, Beijing’s official mouthpieceThe People’s Daily Online published an article reporting speculation the unusually large single-barrelled weapon was an electromagnetic rail gun.
U.S. Treasury Set to Borrow Nearly $1 Trillion This Year
February 5th, 2018Via: CNBC:
Don’t look now, but the U.S. government needs to borrow more money at exactly the wrong moment — when interest rates are spiking.
Last week, in a development first reported by The Washington Post, the Treasury Department quietly released data estimating its 2018 borrowing needs would check in at $955 billion, then top $1 trillion in the next two fiscal years. Those sums are considerably higher than last year’s $519 billion in debt issued last year, and an upward revision to estimates released by the Treasury in late 2017.
The Breakneck Rise of China’s Colossus of Electric-Car Batteries
February 3rd, 2018Via: Bloomberg:
The next global powerhouse in the auto industry comes from a small city in a tea-growing province of southeast China, where an unheralded maker of electric-vehicle batteries is planning a $1.3 billion factory with enough capacity to surpass the output of Tesla and dwarf the suppliers for battery-powered cars by GM, Nissan and Audi.
Contemporary Amperex Technology Ltd., or CATL, already sells the most batteries to the biggest electric-vehicle makers in the biggest EV market: China. Now it wants to use proceeds from a pending initial public offering backed by Goldman Sachs Group Inc. to get under the hoods of more European marques and secure customers in the U.S.
Syrian Rebels Down Russian Plane, Kill Pilot
February 3rd, 2018Via: Reuters:
Syrian rebels shot down a Russian warplane on Saturday and killed its pilot on the ground after he ejected from the plane, Russia’s defense ministry and Syrian rebels said.
The SU-25 came down in an area of northern Idlib province that has seen heavy air strikes and fighting on the ground between Syria’s government forces backed by Russia and Iran, and rebel groups opposed to President Bashar al-Assad.
Syrians opposed to Assad see Russia as an invading force they blame for the deaths of thousands of civilians since Moscow joined the war on the side of the government in 2015.
The U.S. State Department said it had seen reports about the incident and allegations that the United States provided missiles to groups in Syria.
“The United States has never provided MANPAD missiles to any group in Syria, and we are deeply concerned that such weapons are being used,” said State Department spokeswoman Heather Nauert. “The solution to the violence is a return to the Geneva process as soon as possible and we call on Russia to live up to its commitments in that regards.”
The Russian plane was shot down over the town of Khan al-Subl near the city of Saraqeb, close to a major highway where the Syrian army and Iranian-backed militias are trying to advance, a rebel source said.
Although the Russian pilot escaped the crash, he was killed by rebels who had tried to capture him, the source said.
Cellphone Radiation Linked To Tumors In Male Rats, Government Study Says
February 3rd, 2018Via: CBS:
High exposure to radiofrequency radiation — the radiation known as RFR and emitted from your cell phone — causes a rare cancer in male rats, according to draft conclusions released by the National Institutes of Health on Friday.
The two technical reports, one on mice and the other on rats, released by the NIH’s National Toxicology Program (NTP) show the exposure to the high levels of radiation resulted in tumors in the tissues surrounding nerves in the heart of male rats.
Both male and female rats that were exposed to high levels of RFR showed increased patterns of damage to their heart tissue, according to the researchers.
“The levels and duration of exposure to RFR were much greater than what people experience with even the highest level of cell phone use, and exposed the rodents’ whole bodies. So, these findings should not be directly extrapolated to human cell phone usage,” said NTP senior scientist Dr. John Bucher in a written statement. “We note, however, that the tumors we saw in these studies are similar to tumors previously reported in some studies of frequent cell phone users.”
Related: Dr. Martin Pall, Ph.D.: Electromagnetic Field Exposure – The Cellular Effect on Humans
Trump Says It Will Be Hard To Unify Country Without A ‘Major Event’
February 2nd, 2018Via: PBS:
Hours before his first State of the Union, President Donald Trump said Tuesday that he wants to unite the country amid “tremendous divisiveness” and hopes he can do so without a traumatic event affecting Americans.
Trump spoke about creating a more united country during a lunch with a number of television news anchors. Trump said the United States has long been divided, including during the impeachment of former president Bill Clinton. Trump also said that Americans usually come together during times of suffering.
“I would love to be able to bring back our country into a great form of unity,” Trump said. “Without a major event where people pull together, that’s hard to do. But I would like to do it without that major event because usually that major event is not a good thing.”
Airbus Tests Self-Flying Taxi
February 2nd, 2018Via: AFP:
Airbus said Friday that it had successfully held the first test flights of the Vahana, an electric, pilotless flying vehicle that it hopes will be able to ferry people around cities.
The Wednesday flight at a test range in the US state of Oregon lasted just under one minute, with the aircraft lifting up five metres (16 feet) from the ground and landing without control from a pilot, the European aerospace firm said in statement.
