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Astronomers Solve the Mystery of 'Hanny's Voorwerp' 123

KentuckyFC writes "In 2007, a Dutch school teacher named Hanny van Arkel discovered a huge blob of green-glowing gas while combing though images to classify galaxies. Hanny's Voorwerp (meaning Hanny's object in Dutch) is astounding because astronomers have never seen anything like it. Although galactic in scale, it is clearly not a galaxy because it does not contain any stars. That raises an obvious question: what is causing the gas to glow? Now a new survey of the region of sky seems to have solved the problem. The Voorwerp lies close to a spiral galaxy which astronomers now say hides a massive black hole at its center. The infall of matter into the black hole generates a cone of radiation emitted in a specific direction. The great cloud of gas that is Hanny's Voorwerp just happens to be in the firing line, ionizing the gas and causing it to glow green. That lays to rest an earlier theory that the cloud was reflecting an echo of light from a short galactic flare up that occurred 10,000 years ago. It also explains why Voorwerps are so rare: these radiation cones are highly directional so only occasionally do unlucky gas clouds get caught in the crossfire."

Comment Re:Unfair? Maybe. Overdue? Definitely. (Score 1) 67

That's cool! I appreciate your concerns about Constellation. There's a lot of bad press and unfortunate misinformation floating around, yet despite that it's extremely important to listen to the criticism.

Ares may be a polished turd, but it's the best turd ever built to date. It has the most thorough fault detection, caution and warning and abort systems of any human rated launch vehicle. First stage is reusable, just like Shuttle solid rocket motors. Hypergol and cryogenic handling is safer and more efficient than legacy systems. Block II first stages may even eliminate hydrazine completely in favor of electromechanial thrust vector control actuators. If first stage leaks, at a case or nozzle joint, the resulting side thrust can be easily countered until the end of first stage burn. Since it's not a side-mount, the escaping gas won't harm anything. We've got fault detection in both the forward and aft skirt in case of leaks on either end of the case.

1. "Black zones": In the event of an uncontained failure, the launch abort system can escape cleanly even near max Q. Ares has no "black zones", despite what the tinfoil crew may claim. Escaping from an uncontained failure is not just a requirement for solid boosters; liquid engines can blow up, too.

2. Thermal Protection Systems (TPS): Orion has sufficient thermal protection to make a worst case straight in ballistic re-entry at any point during ascent, and the capsule floats well enough and has enough life support on board to safely come down anywhere on the planet. The competing lightweight commercial capsules, launched on EELV's, do not have TPS scaled for re-entry from a lunar mission, and it's unknown if they'd even survive the heat of a ballstic North Atlantic re-entry.

3. Failsafe insertion: Ares inserts Orion in an elliptical orbit with a negative perigee altitude. If something goes horribly wrong on Orion, they come down safely in half a rev. Contrast this with the CCTS approach, naively copied from commercial satellite launching - they put their capsule (and upper stage) into a long lifetime circular orbit. If the capsule has a failure, they're stuck up there. Depending on which version you look at, the commercial crew aren't even wearing launch and entry suits.

Ares I is the safest rocket ever built. I'm proud to be a part of it. Regardless what goes on at the executive level, Constellation remains the Program of Record and it will literally take an act of Congress to kill it. Until then, Obama's proposed budget is just that: proposed.

Comment Re:Unfair? Maybe. Overdue? Definitely. (Score 1) 67

no possibility of practical stage re-use.

The solid rocket motors are reusable. I'm sorry, but you're wrong.

Once the rocket segments have been poured and cured they're effectively "loaded" and have to be handled with great care to make sure there's no possibility of accidental ignition -- something totally avoided with liquid fuel rockets where the oxidiser and fuel are kept completely separately

Red herring argument. Cryogenic liquid oxygen is way more dangerous and expensive to handle than loaded solid propellant.

I'm just glad that the Ares-I got cancelled before it killed yet more astronauts.

It isn't canceled. Constellation won't be canceled unless congress approves the Obama budget. Unless that happens, NASA is required by law to continue working the program of record. Just curious: which space industry do you work in? Your British spelling makes me curious :)

Comment Re:Unfair? Maybe. Overdue? Definitely. (Score 1) 67

CxP takes Shuttle and other legacy technology and tries to make it safer than any of the previous systems ever were. Apollo and Shuttle were developed without any idea what the reliability would be or what the risks were. Constellation was given the go-ahead with the understanding that it would be made much MUCH safer. Unfortunately, we actually tried to make it that much safer and the peanut gallery wondered why it was costing so much.

Comment Re:Constellation was a joke (Score 2, Interesting) 67

Funny thing is, the baselined CCDev trajectories are standard commercial satellite trajectories. The EELV upper stage inserts the crew capsule directly into a circular decay for at least a week. This was rationalized away by requiring scale up RCS on the crew capsule with enough delta-V to deorbit the capsule in the event of a service module engine failure. To their credit, Boeing's commercial capsule does this. Can't say for sure about Lockmart or Space-X.

Comment Re:Constellation was a joke (Score 2, Interesting) 67

ULA has no idea what they're getting into, trying to man-rate Delta and Atlas. Yet even as an Ares I engineer I'm helping them to get there. As for Space-X, they're the Moller Skycar of the spaceflight business. In the past, even mentioning Direct would have gotten you dismissed as a tinfoil hatter yourself, but actually, one of the proposed HLV's to come out of Hanley's study last week had 4 segment solids with an SSME or RS-68 core. Very Direct-like, but without the woo.

Comment Re:Not to sound like a tinfoil hat... (Score 1) 67

Obama *is* a darn politician. NASA's charter is not to buy off-the-shelf hardware, but rather to R&D low technology readiness level (TRL) projects and to and operate missions that no commercial entity would consider. I work in a small section of CxP, and coincidentally have also been an advisor to some CCTS work. I can assure you, NASA (and our contractors, of course) have our human spaceflight shit together way more than ULA/Boeing/Space-X et. al. In fact, ULA would even be attempting to human-rate their launch vehicles if it wasn't for NASA funding them to do the work! Private (that is, commercial) industry is not anywhere near ready for human spaceflight. Oh, and you know those

Man Put On "No-Fly List" While In Air To NYC 300

An unnamed man flying from Nigeria to New York City found out he was added to a no-fly list somewhere above the Atlantic Ocean, when the plane stopped to refuel in San Juan, Puerto Rico. Officials won't say what he did or why he was added to the list after he had already boarded a flight. He was not immediately charged with a crime and Customs and Border Protection will only say that he is a "potential person of interest." From the article: "The man, a citizen of Gambia, was not on the no-fly list when he boarded the aircraft in Dakar, Senegal, said a US official who spoke on condition of anonymity because he was not authorized to discuss the issue publicly."

Comment Re:Oh really? (Score 1) 533

I'd love to brighten the lives of regular Chinese people, but what can you do when their government insists on doing the very opposite? It's not like the Berlin Airlift where you can just drop uncensored internet from the sky like candy.

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