[DrCaleb]

$1:

Juno will remain in its current orbit around Jupiter

Alas, poor Juno’s polar orbit. We knew it.

NASA’s Jupiter orbiter, which arrived at our largest planet in July, has been given new mission parameters: stay in its 53-day orbit instead of burning into a 14-day polar orbit. At perijove, the closest point to the planet, it skims just 2,600 miles (4,184 km) above the top layer of clouds. The probe then measures the weather and magnetic fields of the planet, trying to determine the interior of the planet. Because the craft flies over the ecliptic of Jupiter, it poses little risk of collision with any of the jovian moons.

A planned thruster firing in August went awry. That would have shrunk the orbit down, with a second burn bringing it closer to a roughly circular orbit so close that it would have fried the imaging instrument. The rest of the instruments are buried in a radiation-proof “vault” deep within the probe. Another attempt in October was thwarted by faulty helium valves, leading the team to skip a third attempt in October at perijove.

http://www.astronomy.com/news/2017/02/j ... nd-jupiter

[DrCaleb]

$1:

NASA’s longshot bet on a revolutionary rocket may be about to pay off

Franklin Chang-Díaz bounds up a handful of stairs and peers through a porthole cut into the side of a silver, tanker-truck-sized vacuum chamber. Inside, a blueish-purple light shines, unchanging and constant, like a bright flashlight. “It looks kind of boring,” Chang-Díaz admits. “But that plume is 3.5 million degrees. If you stuck your hand in that, it would be very bad.”

Truth be told, the plume does not look impressive at all. And yet the engine firing within the vacuum chamber is potentially revolutionary for two simple reasons: first, unlike gas-guzzling conventional rocket engines, it requires little fuel. And second, this engine might one day push spacecraft to velocities sufficient enough to open the Solar System to human exploration.

This has long been the promise of Chang-Díaz’s plasma-based rocket engine, Vasimr. From a theoretical physics standpoint, Vasimr has always seemed a reasonable proposition: generate a plasma, excite it, and then push it out a nozzle at high speed. But what about the real-world engineering of actually building such an engine—managing the plasma and its thermal properties, then successfully firing it for a long period of time? That has proven challenging, and it has led many to doubt Vasimr’s practicality.

Sure, the naysayers say, Chang-Díaz is a wonderful fellow. Hard worker. Brilliant guy. And at a time when the national discourse assails the value of Spanish-speaking immigrants, his story offers a powerful counter to that narrative. Speaking almost no English at the time, he immigrated to the United States from Costa Rica in 1969 to finish high school. Chang-Díaz then earned a doctoral degree in plasma physics from Massachusetts Institute of Technology. Later, as an astronaut, Chang-Díaz flew seven Space Shuttle missions, tying Jerry Ross’ record for most spaceflights by anyone, ever.

All the while, from his first days at Johnson Space Center when he installed an early Internet connection to work with data from his Boston-based plasma physics lab, Chang-Díaz nurtured dreams of linking his science background with his career as a flier. Slowly, he developed the theory of a plasma rocket and began to build prototypes. All along, the critics whispered it just wasn’t feasible.

Only, now it just might be. As part of a program to develop the next generation of in-space propulsion systems, NASA awarded Chang-Díaz’s company, Ad Astra, a three-year, $9 million contract in 2015. This unlocked an opportunity long awaited—a chance to prove the doubters wrong. Naturally, it won't be easy. Ad Astra must fire its plasma rocket for 100 hours, at a power level of 100 kilowatts, next year.

This February, the company has worked about halfway through that contract, and Ars has been keeping tabs on progress in the lab. So far, the immigrant from Costa Rica seems to be holding up his end of the bargain. NASA gave the company a sterling review after the first year of the agreement. Still, there is a ways to go. During a visit this month, the Vasimr engine fired at 100kW for 10 seconds and 50kW for one minute.

https://arstechnica.com/science/2017/02 ... o-pay-off/

[DrCaleb]

Live NASA event going on now, they say they've found 7 Earth sized planets in the 'goldilocks' zone in the 'Trappist' system.

40 light years away!

[DrCaleb]

0:

trappist-1.JPG [ 34.78 KiB | Viewed 782 times ]

[DrCaleb]

Correction - 7 planets in the system, only 3 are in the habitable zone. Trappist 1e, 1f and 1g.

[DrCaleb]

NASA story just popped up:

https://www.nasa.gov/press-release/nasa ... ets-around

[Robair]

You beat me to it.

Pretty cool. Something to aim your plasma rocket at!

[DrCaleb]

Robair Robair:

You beat me to it.

Pretty cool. Something to aim your plasma rocket at!

Yup!

3 more planets we can move to and completely fuck up also!

[Robair]

Maybe Trump will see real estate possibilities and increase funding.

[raydan]

DrCaleb DrCaleb:

Correction - 7 planets in the system, only 3 are in the habitable zone. Trappist 1e, 1f and 1g.

We're practically next door neighbours.

[Strutz]

DrCaleb DrCaleb:

NASA story just popped up:

https://www.nasa.gov/press-release/nasa ... ets-around

Very interesting for sure!

[DrCaleb]

raydan raydan:

DrCaleb DrCaleb:

Correction - 7 planets in the system, only 3 are in the habitable zone. Trappist 1e, 1f and 1g.

We're practically next door neighbours.

It might seem like it's far away - 40,000,000 years one way by jet plane - but it's actually not. If the above plasma engine could accelerate a ship to a healthy percentage of the speed of light, say 40%, the trip could be done in a couple generations earth time and a probe could send telemetry back inside of 150 years or so!

You and I might not see it, but it would still be cool.

The fact though that so many Earth sized planets were found around a Red Dwarf is the really cool part. We've generally only been looking around stars like our Sun. We didn't think a Red Dwarf could form planets other than super Earths or Gas giants. Since Red Dwarfs are pretty common (if Jupiter were 75% heavier, it would be a Red Dwarf), that means our estimates of an average 8 planets per star in the galaxy is a little low. There may be all sorts of planets out there where liquid water may exist, and at least on Earth, where there is Water, there is life.

[DrCaleb]

Seeing a planet for yourself is a very cool experience. If you have a pair of binoculars, here's something special you can do tonight.

With your back facing North, find the brightest star you can see in the West. It's actually Venus. Now, hold your fist up, so that Venus is at the bottom of your fist, and near the top of your fist you should see a red star. That's Mars. Now, hold a finger up to Mars, and go up about the width of your finger and you should see a green star. Well, stars don't come in green. That's actually the planet Uranus.

Is should be visible through binoculars of about 10X magnification, if you are in a fairly dark place.

[DrCaleb]

$1:

Celebrate Supernova 1987A’s 30th birthday with a stellar image set

On the night of February 23, 1987, the first light reached Earth from the death of a massive star in the nearby Large Magellanic Cloud (LMC). For those in the Southern Hemisphere, a new star appeared in the sky and remained visible to the naked eye for months, peaking in brightness in May of that year before it faded from view. Dubbed SN 1987A, this event occurred a mere 166,000 light-years away and provided astronomers with unparalleled insight into the end stages of massive stars. In celebration of the 30th anniversary of this event, NASA is releasing new images and information about SN 1987A.

SN 1987A has greatly furthered our understanding of the supernova process and the stages that both precede and follow it. In a press release, Robert Kirshner of the Harvard-Smithsonian Center for Astrophysics and the Gordon and Betty Moore Foundation explained, “The 30 years' worth of observations of SN 1987A are important because they provide insight into the last stages of stellar evolution.”

Thirty years ago, astronomers’ understanding of supernovae was limited at best, simply because no nearby events had been observed with any appreciable resolution. But SN 1987A is located in the Tarantula Nebula of the Milky Way’s satellite galaxy, the LMC, and was the brightest supernova visible from Earth since 1604. Although ground-based telescopes were only able to resolve the resulting remnant as a small blob, the Hubble Space Telescope (HST) began taking high-resolution images of SN 1987A in 1990, revealing in detail the structure surrounding this former star.

Astronomers have continued to image SN 1987A in great detail with HST and other telescopes over the years, including the Chandra X-ray Observatory and, more recently, the Atacama Large Millimeter/submillimeter Array (ALMA). These images have revealed a ring-like structure around the supernova’s progenitor star that was ejected from the star 20,000 years before its explosive death. Not only is there a main ring surrounding the supernova remnant, but two outer rings as well that give the object an hourglass shape.

http://www.astronomy.com/news/2017/02/h ... nova-1987a

NASA's Chandra X-Ray telescope also has a page dedicated to the anniversary:



http://chandra.si.edu/deadstar/sn1987a.html

And there are animations of all the images taken over the past 30 years. This reminds us that the Universe is only static to our brief perceptions of it.

http://chandra.harvard.edu/photo/2007/s ... tions.html

[DrCaleb]

$1:

New NOAA satellite captures first solar images

NOAA’s new satellite successfully captures a large coronal hole on the surface of the sun.

The Solar Ultraviolet Imager (SUVI) onboard the satellite has taken its first solar images, and NOAA has stitched them together to create a video that you can watch after the break. The images, taken on January 29th, show a large coronal hole in the sun’s southern hemisphere.

The sun’s 11-year activity cycle is currently approaching solar minimum, and during this time powerful solar flares become scarce and coronal holes become the primary space weather phenomena – this one in particular initiated aurora throughout the polar regions. Coronal holes are areas where the sun’s corona appears darker because the plasma has high-speed streams open to interplanetary space, resulting in a cooler and lower-density area as compared to its surroundings.

SUVI is a telescope that monitors the sun in the extreme ultraviolet wavelength range. SUVI will capture full-disk solar images around-the-clock and will be able to see more of the environment around the sun than earlier NOAA geostationary satellites.

The sun’s upper atmosphere, or solar corona, consists of extremely hot plasma, an ionized gas. This plasma interacts with the sun’s powerful magnetic field, generating bright loops of material that can be heated to millions of degrees. Outside hot coronal loops, there are cool, dark regions called filaments, which can erupt and become a key source of space weather when the sun is active. Other dark regions are called coronal holes, which occur where the sun’s magnetic field allows plasma to stream away from the sun at high speed. The effects linked to coronal holes are generally milder than those of coronal mass ejections, but when the outflow of solar particles is intense – can pose risks to satellites in Earth orbit.

http://canadajournal.net/science/new-no ... 5960-2017/