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Over the span of 135 shuttle flights between 1981 and 2011, no shuttle was ever launched, in space, or guided to re-entry on New Year’s in order to avoid any unforeseen problems with the onboard systems.
From the archives: “The capsule is out there like a wrecking ball."
The Catalog
I have compiled a catalog of over 1000 artificial objects in `deep space'. Version 1.0 of this catalog has been released online at https://planet4589.org/space/deepcat.
By deep space, I mean broadly space beyond the region where the US satellite catalog provides coverage. Note that the term has been used with a variety of definitions. In the context of the SGP4 orbit model [3], deep space' refers to orbital periods above 225 minutes, corresponding to altitudes of about 5900 km, a region normally thought of as
medium Earth orbit' these days. For our purposes a boundary somewhere beyond 50,000 km seems needed. It also appears desirable to exclude communications satellites on supersynchronous transfer orbits which have apogees typically in the 60,000 to 100,000 km range.
For definiteness I adopt a boundary I call [14] EL1:4, the Earth-lunar 1 to 4 orbit resonance in which a satellite in a circular orbit will complete four revolutions of the Earth for every one that the Moon does. EL1:4 is at 152066 km from Earth's center. The choice is motivated by the idea that satellites well within this distance can to first order ignore the Moon and be regarded as being in simple Keplerian orbits on short timescales (clearly, even much closer in at GEO, lunisolar perturbations are important on longer timescales). Satellites at this distance or beyond are more strongly affected by lunar perturbations and should be considered as part of a three-body system. This distinction is obviously not a sharp one and is somewhat arbitrary but it seems as good as any. It also echoes the Sun-Jupiter 1 to 4 resonance which approximately marks the inner edge of the asteroid belt and which serves as a good candidate for a boundary between the inner and outer solar system.
Space situational awareness (SSA), for all its challenges, is relatively mature in LEO and GEO. In comparison, the situation beyond GEO is chaotic. No organization is charged with maintaining SSA for deep space objects either in distant Earth orbit or beyond Earth orbit. There is no formal interface between the astronomers who accidentally detect deep space objects while searching for asteroids and the astronautics community. Organizations such as JPL keep track of their own active probes but not of their discarded rocket stages nor the probes of other nations. This situation has been tenable due to the low flight rate of deep space missions to date, but that is changing with the arrival of commercial lunar missions and deep space cubesats, and the increasing number of states carrying out deep space exploration. I present a historical database of about 1000 deep space objects and argue that the time has come to plan for internationally coordinated deep space traffic management.
In the 1960s, NASA commissioned Grumman Aircraft to build 15 space-worthy lunar modules, or LMs, for its Apollo program.
The fate of 14 modules is well-documented, but the last - LM-14 - is harder to account for in historical records. We attempted to track down and piece together the mystery of the seemingly missing moon lander.
Most experts we contacted weren't sure where it had gone, but we finally got a convincing answer (with documentation) from one space historian and artist.
- He believes the lander was scrapped and its aerospace-grade metal possibly reused in jet fighters.
The as-yet-unnamed craft could fly early next year.
An image taken from the International Space Station of a crewed Soyuz capsule launching to visit the facility on Sept. 25, 2019.
(Image credit: Christina Koch/NASA)
"I am concerned that the decisions are not being driven by what is most efficient." //
Bridenstine has decided that it is best to focus efforts on getting the core stage flying as soon as possible. Three SLS rocket flights by 2024 are probably all that Boeing can handle due to "performance issues" cited several times by Bowersox during Wednesday's hearing. This third flight would culminate in the Moon landing at the lunar south pole.
The NASA chief has also defended development of the Gateway as a critical component of a "sustainable" return to the Moon. Instead of emulating Apollo's "flags and footprints" missions from half a century ago, NASA would instead like to return to the Moon to stay and eventually send humans to Mars, using the Gateway as a staging point. //
added, "I am concerned that the decisions are not being driven by what is most efficient or effective and what is most cost efficient.”
This is an interesting viewpoint given that commercial rockets cost $100 to $200 million, at most, versus the $1 billion to $2 billion cost of a single SLS rocket—not including the hundreds of millions of dollars, at a minimum, the agency would have to invest in Exploration Upper Stage development contracts with Boeing. Moreover, one of the commercial rockets—the Falcon Heavy—already exists and has flown three successful missions. //
An SLS rocket with the better upper stage almost certainly wouldn't be ready by 2024, and NASA knows this.
"At this point, there is no path by which the Exploration Upper Stage will be ready for Artemis 3 in 2024," the NASA administration source told Ars. "Hence, it is not in the critical path (for the Moon landing)."
Get yourself a heat shield, and throw the parcel really hard—backward. //
The Earth’s atmosphere weighs as much as a layer of water 10 meters thick. To figure out whether a meteor is likely to make it through, you can imagine that it’s literally hitting a 10-meter layer of water. If the object weighs more than the water it would have to push aside to reach the surface, it will probably make it through. This works pretty well for a rough approximation!
We’ve been sending gender-diverse crews to space since 1983. We’ve had women do every job a man does in space. Every one. Space walks? Check. Shuttle commander? Check. Space Station commander? Check. Record for long-duration flights? Check. So what’s going to be the new gender-bias thing NASA needs to start — start? — paying attention to?By the time I flew in space in the ‘90s, those things had changed; they’d evolved, emerged, progressed and been accommodated for. By then a crew member was just a crew member. The same is true today. They get what they need physically, personally and emotionally to support them in spaceflight. Not a big deal. So why the continued insistence on making it a big deal? //
And why keep bringing up the NASA-doesn’t-make-a-spacesuit-that-fits-a-woman story? The truth behind the cancellation last April of the “all-female spacewalk” was that it was a woman’s call! After doing her first spacewalk, Anne McClain realized that the task on the next one would require a longer arm reach than she had. Sure, they could have redesigned the choreography for that spacewalk, taken the time and the effort to delay the mission, replan and retrain for it. “But why?” she said. Let crewmate Nick Hague do it — he’s trained and he has a longer reach. Need a different tool to get the job done? Go to the toolbox and get a different tool. //
Dr. Mark’s big pitch is that diversity demands attention, especially in situations like a long space flight during which people have to understand their differences and get along. Well, what about six men and women on the Space Shuttle or the International Space Station representing multiple nationalities, different ethnicities and religions, and — in their home countries — competitive political ideologies? That’s not diverse enough for you? NASA has been doing this quietly and efficiently and without fanfare for the better part of the past 36 years.
An Iranian space rocket appears to have exploded on the launch pad at the Imam Khomeini Space Center. It would be the third such failure this year.
Here on Earth, the ability to generate electricity is something we take for granted. We can count on the sun to illuminate solar panels, and the movement of air and water to spin turbines. //
Since 2015, NASA and the United States Department of Energy have been working on the Kilopower project, which aims to develop a small, lightweight, and extremely reliable nuclear reactor that they believe will fulfill this critical role in future off-world exploration. Following a series of highly successful test runs on the prototype hardware in 2017 and 2018, the team believes the miniaturized power plant could be ready for a test flight as early as 2022. Once fully operational, this nearly complete re-imagining of the classic thermal reactor could usher in a whole new era of space exploration. //
it’s more like an evolved version of the radioisotope thermoelectric generators (RTGs) which NASA has used to power everything from the Voyager missions to the Curiosity rover. There’s no dangerous high pressure steam, finicky turbines to spin, or coolant pumps to fail. Thermal energy is passively carried away from the reactor core using sodium-filled heat pipes, which lead to the “hot” side of a Stirling engine array. With a large deployable radiator on the other side, the Stirling engines would use the temperature differential to produce reciprocal motion that can drive a small generator.
The Kilopower has been designed as a self-regulating system where everything happens automatically and without the need for external control. There would naturally be sensors for basic diagnostics, for example checking temperatures at key points in the system, the RPMs of the Stirling engines, and the output of the generators. But outside of monitoring for these possible signs of trouble, the human crew could largely ignore the Kilopower and go about their mission.
At one point in time, the United Launch Alliance (ULA) - infamous for partially enforcing a monopoly over US launch markets and relying on old but proven technology - was actively pursuing advanced tech that could eventually enable orbital propellant depots and create what was described as a "cislunar economy".
Led in large part by former Vice President of Advanced Programs George Sowers (2006-2012, 2015-2017), ULA has pursued orbital refueling and propellant depots for the better part of a decade. //
Apparently, after he began a renewed push for propellant depots and reusable upper stages in 2015, Boeing quite literally tried to have him fired, clearly taking the depot concept as a direct threat to a big slice of pork: NASA's Space Launch System (SLS) Core Stage (booster) contract. //
"Senator [Richard] Shelby [R - AL] called NASA and said if he hears one more word about propellant depots, he’s going to cancel [NASA's] space technology program." //
NASA has spent more than $2B annually on SLS alone in FYs 2017, 2018, and 2019, accounting - as of October 2019 - for nearly $6.5B spent on SLS in the last three years alone. SLS funding is likely to be increased yet again by Congress in FY2020. Since the Constellation Program's (2005-2010) Ares V rocket was rebirthed as the SLS program in 2011, NASA has spent more than $16B on the rocket alone, while its launch debut has slipped more than 4 years (late 2017 to late 2021). //
Whatever the end result, Sowers' blunt description of how Boeing (and SLS) have stunted US spaceflight innovation for years is simultaneously depressing and unsurprising, but serves as an extremely rare instance of candor from a former executive of a traditional US aerospace company.
"To look forward to the Moon, we need to learn from the past." //
The reality is that, even with a healthy budget increase, NASA can barely afford a human landing program on the Moon in the 2020s—at least using its Space Launch System rocket and usual ways of doing business, as it appears set on doing. This is more than enough for a space agency that has not flown a human into deep space for 47 years.
Talk of Mars is historically unsupportable with current budgets or NASA's existing technology. (As just one example, NASA at best can build one SLS rocket a year, and a single human mission to Mars would require six to eight SLS rocket launches). Past efforts to go to the Moon, Mars, or both have all ended in cancellation. So by talking about an all-of-the-above Moon-to-Mars exploration plan now, NASA's administration seems to be moving from the edge of the possible into the realm of the impossible
Although alternatives such as SpaceX’s Falcon Heavy exist, the space agency is legally required to launch its Europa Clipper spacecraft on the behind-schedule Space Launch System //
The current appropriations bill mandates Europa Clipper use the SLS and requires a “launch no later than 2023” on the rocket. //
Each SLS launch is estimated to run more than $1 billion. //
2025—or on something other than the SLS—it would be in violation of current law, which means the law must change or a working SLS must suddenly appear in order for Europa Clipper to take off in accordance with federal statute. //
The SLS has an undeniable advantage over Falcon Heavy: it enables a direct flight from Earth to Jupiter. Falcon Heavy will require gravity assists from other planets, and unless it uses an add-on “kicker stage”—an additional upper stage for extra loft—one of those gravity assists will require an encounter with Venus. According to Salute, a Venus flyby introduces “a riskier environment, radiation and temperature. And so we would like to avoid flying closer to Venus with this direct trajectory that SLS affords us.
NASA is rationing watts to keep its oldest mission going. //
Beyond Earth and its bubble of satellites; past Mars, where rovers explore; past Jupiter and its circling orbiter—outside the solar system entirely—two spacecraft are gliding across interstellar space. They have crossed over the invisible boundary that separates our solar system from everything else, into territory untouched by the influence of the sun. People have seen much deeper into the universe, thanks to powerful telescopes that catch the light of distant stars. But this is the farthest a human invention has ever traveled. These hunks of gleaming metal and circuitry—they are the furthermost tangible proof of our existence. //
They prepare for what may be the mission’s final years. “Someday we’re going to have to say goodbye,” says Candy Hansen, a scientist at the Planetary Science Institute who worked on the Voyager mission in the 1970s and 1980s.
But not yet. This summer, engineers instructed Voyager 2 to fire up a set of thrusters that the spacecraft hasn’t used since 1989.
Plasma shocks are the primary means of accelerating electrons in planetary and astrophysical settings throughout the universe. Which category of shocks, quasi-perpendicular or quasi-parallel, accelerates electrons more efficiently is debated. Although quasi-perpendicular shocks are thought to be more efficient electron accelerators, relativistic electron energies recently observed at quasi-parallel shocks exceed theoretical expectations. Using in situ observations at Earth’s bow shock, we show that such relativistic electrons are generated by the interaction between the quasi-parallel shock and a related nonlinear structure, a foreshock transient, through two betatron accelerations. Our observations show that foreshock transients, overlooked previously, can increase electron acceleration efficiency at a quasi-parallel shock by an order of magnitude. Thus, quasi-parallel shocks could be more important in generating relativistic electrons, such as cosmic ray electrons, than previously thought.
A NEW SOURCE OF SPACE RADIATION: Astronauts are surrounded by danger: hard vacuum, solar flares, cosmic rays. Researchers from UCLA have just added a new item to the list. Earth itself.
“A natural particle accelerator only 40,000 miles above Earth’s surface is producing ‘killer electrons’ moving close to the speed of light,” says Terry Liu, a newly-minted PhD who studied the phenomenon as part of his thesis with UCLA Prof. Vassilis Angelopoulos.
This means that astronauts leaving Earth for Mars could be peppered by radiation coming at them from behind–from the direction of their own home planet.
NASA’s THEMIS spacecraft ran across the particles in 2008 not far from the place where the solar wind slams into Earth’s magnetic field. Researchers have long known that shock waves at that location could accelerate particles to high energies–but not this high. The particles coming out of the Earth-solar wind interface have energies up to 100,000 electron volts, ten times greater than previously expected.
How is this possible? Liu found the answer by combining THEMIS data with computer simulations of the sun-Earth interface. When the solar wind meets Earth, it forms a shock wave around Earth’s magnetic field, shaped like the bow waves that form ahead of a boat moving through water. Within this “bow shock” immense stores of energy can be abruptly released akin to the sonic boom of an airplane.
Liu found that some electrons are shocked not just once, but twice or more, undergoing mirror-like reflections within the bow shock that build energy to unexpected levels. Most of the boosted particles shoot back into space away from Earth.
The Beresheet lunar lander carried thousands of books, DNA samples, and a few thousand water bears to the moon. But did any of it survive the crash?