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Lovejoy gets a big head and grows an extra tail: up to the minute details on the death of a comet

December 15th, 2011 Comments off

lovejoy_iontail


3:52 pm (EST) Thursday

I just got off the phone with Jack Ireland and Alex Young, solar scientists who work at Goddard and are following Comet Lovejoy’s demise closely. Look what’s happening to the comet!

First, see how bulbous and weird the head of the comet is? That’s because the incredible brightness of the comet’s head is overwhelming the detectors on the SOHO satellite. The photons are “bleeding” out to form that cross-like pattern.

It gets interestinger and interestinger: Two distinct tails have formed. “The thick white tail is primarily dust breaking away from the comet nucleus,” Ireland explained in an email. “It’s the Sun’s radiation and solar wind that knocks the material off the comet nucleus.”

But to the left of the dust tail, do you see that faint wispy second stream? That is a tail of charged particles (ions) being deflected to the side by the magnetic field carried by the solar wind.

The coolest thing is that this is all happening right now.

Word is that the comet will pass behind the sun at around 7 pm tonight (EST). It may or may not come out the other side in its orbit. It depends how massive the comet is and how long it survives the pounding of the solar wind.

lovejoy-bighead

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.




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Comet Lovejoy plunges into the sun!

December 15th, 2011 Comments off

3:52 pm (EST) Thursday

I just got off the phone with Jack Ireland and Alex Young, solar scientists who work at Goddard and are following Comet Lovejoy’s demise closely. Look what’s happening to the comet!

First, see how bulbous and weird the head of the comet is? That’s because the incredible brightness of the comet’s head is overwhelming the detectors on the SOHO satellite. The photos are “bleeding” out to form that cross-like pattern.

It gets interestinger and interestinger: Two distinct tails have formed. It gets interestinger and interestinger: Two distinct tails have formed.

“The thick white tail is primarily dust breaking away from the comet nucleus,” Ireland explained in an email. “It’s the Sun’s radiation and solar wind that knocks the material off the comet nucleus.”

But to the left of the dust tail, do you see that faint wispy second stream? That is a tail of charged particles (ions) being deflected to the side by the magnetic field carried by the solar wind.

The coolest thing is that this is all happening right now.

Word is that the comet will pass behind the sun at around 7 pm tonight (EST). It may or may not come out the other side in its orbit. It depends how massive the comet is and how long it survives the pounding of the solar wind.


lovejoy_iontail


Set the controls for the heart of the Sun, Lovejoy!



As tweeted minutes ago earlier by Phil Plait on Bad Astronomy, Comet Lovejoy has begun it’s searing plunge into the sun. Here’s a still image from the video Phil tweeted out:


lovejoyplunge_600.jpg


And here is the image of the comet from NASA’s The Sun Today site:


lovejoy_suntoday_600


Go to Helioviewer.org to find out all the details about Lovejoy and how you can observe it!


While you’re at it, check out the VIDEO on Helioviewer.org of Lovejoy in mid-plunge.


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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.




Highlights of this week’s exoplanet feast at Goddard

October 21st, 2011 Comments off
Spiral signpost of planets

Spiral signpost of planets

This week, it’s been a feast of exoplanet science at Goddard, which hosted the Signposts of Planets meeting Oct. 18-20. The three-day conference gathered an international crowd of observers, computer modelers, and instrument builders to explore the relationship between exoplanets and the circumstellar disks in which they form.

Circumstellar what?

Circumstellar simply means “disks of gas and dust around a star or stars.” Astronomers have discovered some 687 planets around other stars, but ironically they rarely are able to “see” one directly. What the Hubble telescope and other instruments see are dusty disks.

Circumstellar disks are the “signposts of planets” referenced by the name of the conference. Want to find planets? Look for dusty disks.

Here is Goddard astrophysicist and Signpost meeting organizer Marc Kuchner explaining the lowdown on circumstellar disks, back when we only knew of about 400 extrasolar worlds:


The conference produced some show-stoppers in terms of new discoveries announced. Four were the subject of press releases:

Spiral signposts
At the meeting, Goddard astronomer Carol Grady announced the discovery of a type of exoplanet telltale predicted but never actually imaged before. In some circumstellar disks, the tug of a planet’s gravity can create subtle spiral features in the gas and dust. That is good news, because it means that disks with spirals could lead astronomers to planets.

“What we’re finding is that once these systems reach ages of a few million years, their disks begin to show a wealth of structure — rings, divots, gaps and now spiral features,” said John Wisniewski, a collaborator at the University of Washington in Seattle. “Many of these structures could be caused by planets within the disks.”

The newly imaged disk surrounds SAO 206462, a star located about 456 light-years away in the constellation Lupus.

Baby planet

Baby planet

Baby planet
Also at the conference, astronomer Adam Kraus explained how he used the mammoth Keck telescopes on Mauna Kea in Hawaii to image an infant planet. “LkCa 15 b is the youngest planet ever found, about 5 times younger than the previous record holder,” said Kraus, who is based at the University of Hawaii’s Institute for Astronomy.

Kraus did the work using a technique called interferometry, which allows a telescope to achieve the detail-resolving power equivalent to that of a much larger telescope.

Cool findings
In another report at the Signpost meeting, astronomer Kevin Luhman of Penn State University described his observations of a star with a cool planet-like companion. The object, a gaseous not-quite-a-star called a brown dwarf, has an outer temperature described as comparable to “a hot summer day in Arizona.”

Coolest brown dwarf ever

Coolest brown dwarf ever

Luhman commented:

“Its mass is about the same as many of the known extra-solar planets — about six to nine times the mass of Jupiter — but in other ways it is more like a star. Essentially, what we have found is a very small star with an atmospheric temperature about cool as the Earth’s.”

OK, not quite a planet — but not quite a star either. Brown dwarfs lie in between. But they lie along a spectrum of objects that exoplanet researchers study.

Ever since brown dwarfs first were discovered in 1995, astronomers have been trying to find new record holders for the coldest brown dwarfs because these objects are valuable as laboratories for studying the atmospheres of planets with Earth-like temperatures outside our solar system.

Comet storm

Comet storm

And last but not least, comet storms!

NASA’s Spitzer Space Telescope has detected signs of icy bodies raining down in an alien solar system. The downpour resembles our own solar system several billion years ago during a period known as the “Late Heavy Bombardment,” which may have brought water and other life-forming ingredients to Earth.

Carey Lisse, senior research scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland., announced the finding at the Signposts conference. The research will be published in the Astrophysical Journal.

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.








There goes the neighborhood: What will the Webb Telescope reveal about our solar system?

June 7th, 2011 Comments off
Astronomer Heidi Hammel talks about how the Webb Telescope can be used to study our solar system.

Astronomer Heidi Hammel talks about how the Webb Telescope can be used to study our solar system.


The James Webb Space Telescope will look far back in cosmic time to study the origins of the universe.  But that doesn’t mean the observatory will turn a blind eye to the planets. Yesterday, at a conference at the Space Telescope Science Institute (STScI) in Baltimore,  noted planetary astronomer Heidi Hammel gave us a quick tour of the solar system from Webb’s (future) point of view.

UPDATE: A webcast video of Hammel’s talk is now available on the STScI website.

The conference, Frontier Science Opportunities with the James Webb Space Telescope (June 6-8), is all about what Webb can and will do once it makes it into space. It’ll be a while: As Matt Mountain, director of STSciI, mentioned in his opening remarks to the conference, Webb won’t see the cold of space, some 1 million miles from Earth, until at least 2017.

Hammel is known to be a great speaker, and she didn’t disappoint. First she took Mercury, Venus, and Earth out of the lineup. Her Powerpoint slides?

Mercury? No.

Venus? No.

Earth? No.



Webb’s orbit and the size and shape of its sunshield leave these planets in an “exclusion zone” hidden from the observatory’s view. (Its planned orbital perch is a point called L2, opposite from Earth with respect to the sun.) Ok, fine. What about Mars?

Yes. According to a March 9, 2010 White Paper about Webb and the solar system, the observatory could measure a number of important things in Mars’ atmosphere, like dust and carbon dioxide gas, that affect its climate.

Hammel speculated that Webb’s infrared eyes could help solve the mysterious nature of methane releases observed on Mars. Where does the methane come from? Webb might help us figure it out.

Jupiter? Saturn? Yes, yes. There is much Webb could learn about the atmospheres of these giant gas planets — which are, by the way, the best nearby examples we have of the scores of giant gaseous exoplanets being discovered in other solar systems.

Titan, Saturn’s largest moon? Yes. Webb could add a decade of observations of Titan’s surface and atmosphere to the work of the Cassini orbiter, and during a time in Titan’s seasonal cycle not yet explored in the infrared band, according to the White Paper.

Uranus and Neptune? An enthusiastic thumbs up from Hammel to the idea of studying these cool, distant bodies with the Webb’s infrared camera and spectrographs. She cited several scientific puzzles that Webb might help solve, including shifts in the wavelengths of light emitted by Uranus as the planet rotates and Neptune’s inexplicably warm polar region.

In general, Hammel said, “Neptune’s atmosphere is so dynamic, and little is known.” Anything Webb contributes will be helpful.

Last but not least, the region beyond Neptune, realm of Pluto and the other icy dwarf planets, is also fair game for Webb.  As the White Paper explains:

“Beyond Neptune, a class of cold, large bodies that include Pluto, Triton and Eris exhibits surface deposits of nitrogen, methane, and other molecules that are poorly observed from the ground, but for which JWST might provide spectral mapping at high sensitivity and spatial resolution difficult to match with the current generation of ground-based observatories.”

And comets, too. At least comets slow enough for Webb to track.

There has been much public hand wringing lately over growth in the Webb budget and slips in the launch date. But in the scientific community, two generations eagerly await the lofting of the giant Webb observatory into orbit. Many of them are up at STScI today sharing their plans.

“There’s a lot of great science that’s going to come out of this and I’m really looking forward to it,” Hammel said. “There is a wide range of interesting planetary phenomena observable by JWST, especially in the outer solar system.”

This NASA video goes into detail about planet studies — here and elsewhere in the universe — and the James Webb Space Telescope:

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.


That Was The Week that Was, January 10-14, 2011. . . A Digest of Goddard People, Science, & Media, PLUS Historical Tidbits and Our Best Stuff in the Blogpodcastotwitterverse

January 14th, 2011 Comments off

image of coronal hole on sunOn January 10, the Solar Dynamics Observatory snapped this image of the sun in extreme ultraviolet light, capturing a dark coronal hole.

image of hanny's voorwerpMONDAY January 10: Observations of distant galaxies help solve a centuries-old molecular mystery.

Gateway to space: Goddard scientist Harley Thronson, University of Texas partner Dan Lester, and aerospace industry colleague Ted Talay explain today in the Space Review how the United States can maintain a presence in space after the Shuttle and the ISS programs conclude.

Hanny’s what? You probably can’t pronounce it correctly, but the Hubble Space Telescope has snapped a picture of Hanny’s Voorwerp.

Hubble says: Tiny red dwarf stars, smaller than our sun, can unleash powerful eruptions that may release the energy of more than 100 million atomic bombs.

Fermi surprise: Thunderstorms spew antimatter into space!


TUESDAY January 11: The latest Earth-observing satellite developed by NASA, Glory, arrived Tuesday at Vandenberg Air Force Base, Calif., in preparation for a Feb. 23 launch.

Tropical storm warning: NASA’s Aqua satellite flew over the low pressure area known as System 93P in the Southern Pacific Ocean early today and saw rainfall already occurring over Vanuatu.


photo of snow on plant stemWEDNESDAY January 12: Global surface temperatures in 2010 tied 2005 as the warmest on record. And also get the science behind the news: Do annual temperature rankings matter?

Inconstant Crab: X-ray emission from the Crab Nebula is weakening.

Magnificent magnification: As many as 20 percent of the most distant galaxies currently detected appear brighter than they actually are because of the magnifying effect of gravity from other galaxies.

Comet rendezvous: On this day in 2005, NASA launched Deep Impact, the first space mission to probe beneath the surface of a comet. Six months later, on July 3, the spacecraft jettisoned an impactor that crashed into comet Tempel 1. The crash provided the most up-close data and images of a comet in the history of space exploration.

The white stuff: Goddard gets a light dusting of the white stuff. It was no Snowpocalypse, but it was pretty.


photograph of technician and webb telescope mirrorsTHURSDAY January 13: On this day in 1997, NASA scientists announced the discovery of three black holes in three normal galaxies, suggesting that nearly all galaxies may harbor supermassive black holes.

La Nina: A new Ocean Surface Topography Mission (OSTM)/Jason-2 satellite image of the Pacific Ocean captures stronger La Nina cooling in the Pacific.

Two-faced: Hubble Space Telescope captures two radically different views of the Whirlpool Galaxy.

Not-so-heavy metal video: Learn about beryllium, the wonder metal at the heart of the Webb Telescope.

ICESat away: On this day in 2003, NASA launched the ICESat mission. It was the first mission specifically designed to study Earth’s polar regions with a space-based laser altimeter. The mission led to advances in measuring changes in the mass of the Greenland and Antarctic ice sheets, polar sea ice thickness, vegetation-canopy heights, and the heights of clouds and aerosol particles. The ICESat mission ended in February 2010 with the failure of the last of its three lasers. After a controlled maneuver to bring the craft out of orbit, ICESat entered Earth’s atmosphere over the Barents Sea on August 30, 2010. A follow-on mission, ICESat-2, is slated for launch in 2015.

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.




That Was The Week That Was, November 29-December 4, 2010. . . A Digest of Goddard People, Science, & Media, PLUS Historical Tidbits and Our Best Stuff in the Blogpodcastotwitterverse

December 3rd, 2010 Comments off






sateliite image of mexico and central americaMONDAY November 29: The MODIS Image of the Day features southern Mexico and Central America, a striking true-color image of green vegetation and rugged tan mountain tops.

Chimps in space! On this day in 1961, Enos the chimp blasted off on a test flight aboard a Mercury Atlas 5. He experienced a peak acceleration of 7.6 g’s during launch and endured two orbits in just over 3 hours before returning to Earth safely.

More awesomeness: The NASA Blueshift Weekly Awesomeness Round Up features colliding galaxies, a runaway star, and Comet Hartley 2 in 3D.


image of tiger stripe heat map on enceladusTUESDAY November 30: Today NASA’s Cassini spacecraft dipped near the surface of Saturn’s moon Enceladus imaged shadowy regions of the tortured south polar terrain and the brilliant jets that spray out from it.

WEDNESDAY December 1: New images and data from a Cassini fly by Aug. 13, 2010, give scientists a unique Saturn-lit view of active fissures in the south polar region of Saturn’s moon Enceladus.

A week in the sun: The SDOmision2009 YouTube channel features the “7 day sun” video. For seven days (November 13-19), the Solar Dynamics Observatory’s HMI instrument watched as a small sunspot group morphed, merged, and grew into two large sunspots.


soho-cme-202THURSDAY December 2: Today, NASA’s solar and heliospheric observatory (SOHO) marks 15 years in space. SOHO is perhaps best known for its observations of coronal mass ejections, or CMEs. SOHO has, over the years, emerged into the greatest comet-finder of all time. As of November 1, 2010, SOHO had spotted more than 1,940 of comets.

Poison bugs: After days of wild speculation in the press, including false rumors about life discovered on Saturn’s moon Titan, NASA announced discovery of a bacteria that is the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic.

Sofia science: NASA’s Stratospheric Observatory for Infrared Astronomy, or SOFIA, completed the first of three science flights today to demonstrate the aircraft’s potential to make discoveries about the infrared universe. A Goddard team has an instrument aboard the observatory called SAFIRE, “the Far-Infrared Imaging Spectrometer for SOFIA.”

Chimps in space! (See December 2)

Chimps in space! (See Nov. 29)

Black ops: A team led by Goddard’s John Hagopian wins an innovation award for developing an exotic coating that is “blacker than black” and may be used someday to damp stray light pollution on spacecraft. Each year, the Goddard Office of the Chief Technologist bestows the award on those who exemplify the best in research and development at the center. Also, don’t miss the video about Hagopian’s work.

Hubble fix-it team: On this day in 1993, the STS-61 shuttle mission went into space to undertake the first Hubble Space Telescope servicing operation, repairing the observatory’s optics and perform routine servicing.


FRIDAY December 3: On this day in 1973, Pioneer 10 made the first spacecraft observations of Jupiter, passing within 81,000 miles of the cloudtops.

Lost: On this day in 1999, the Mars Polar Lander reached Mars. While attempting a direct entry into Mars’ atmosphere, the probe was lost.


SATURDAY December 4: NASA research physicist Brent Bos gives a presentation about the James Webb Space Telescope at the Imagination Station science center in Toledo, Ohio.

Let’s get started: On this day in 1998, the first International Space Station assembly flight, STS-88, launched.


_____________________________________________________________________________________________________ OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.



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Did I Forget To Mention? Happy 5 Years, Deep Impact Mission!

July 13th, 2010 2 comments
comet crash_202

This spectacular image of comet Tempel 1 was taken 67 seconds after it obliterated Deep Impact's impactor spacecraft.

In last week’s That Was The Week That Was, I neglected to celebrate a significant milestone: July 4, 2010, marked the 5th anniversary of the Deep Impact encounter with Comet 9P/Tempel. On July 4, 2005, the Deep Impact spacecraft hurled a heavy mass into the comet, excavating a crater and exposing fresh interior comet stuff to scientific analysis. Feel free to pause and feast on dramatic comet-smashing images and then catch up on the scientific findings.

Mike A’Hearn at the University of Maryland headed the Deep Impact science team, and NASA’s Jet Propulsion Laboratory in California managed the project. So why is gogblog nattering on about Deep Impact?

One Goddard connection to Deep Impact is asteroid and meteorite scientist Lucy McFadden. She was a member of the Deep Impact science team and led the mission’s education and public outreach effort. She recently joined Goddard as Chief of University and Post-doctoral Programs. Although her job here is administrative, she remains an active researcher.

In Deep Impact’s present configuration, the Goddard links increase.

First, some brief background. The spacecraft is very much alive, and it’s still working for planetary science. The reincarnation of Deep Impact is called EPOXI. It’s actually two missions in one: the Extrasolar Planet Observation and Characterization (EPOCh) mission and the Deep Impact Extended Investigation (DIXI).

Deep Impact Earth-Moon_202EPOCh scrutinized a small number of stars in order to learn more about planets that we know are orbiting those stars, and to search for clues to other planets that might be orbiting the same stars. It also imaged Earth to get insights into how we might recognize an Earth-like world around another star. DIXI will study comet 103P/Hartley 2 during a November 2010 encounter.

McFadden is now working with EPOCh’s observations of Earth — more on this in a  future blog post. And Goddard’s Drake Deming, a leading exoplanet scientist, heads the EPOCh component of EPOXI.

Yep, that’s a lot of acronyms. A little confusing, even. But stay tuned, because you’ll be seeing them more often in the future in the science press and on gogblog.



cell_phone_moon_50***INFO UPDATE: There is a new way to get involved in International Observe the Moon Night: invite yourself on the Facebook Event Page.

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center.




STEREO spacecraft captures comet’s fiery demise: in space, no one can hear a dirty snowball scream as it falls into the sun

June 3rd, 2010 6 comments

One minute you’re a comet soaring through space, free as a bird, and the next you’re solar road kill, evaporating in a psssstttt! of glory.

Scientists at the University of California, Berkeley, recently tracked a comet deeper into the sun’s extended atmosphere than ever before. The comet was consumed in the 100,000-degree heat, but we got to watch. Not a happy ending for the comet, but what a way to go!

These images come courtesy of NASA’s twin STEREO spacecraft, which observed the comet between March 12 and 14, 2010. (Goddard is one of six partners in the mission.) If you were a comet falling into the sun, what would you be thinking?

Ooohhh . . . pretty.

Ooohhh . . . pretty.

Hey, wait a minute, that's THE SUN!

Hey, that's THE SUN!

Getting kind of warm now . . .

Getting kind of warm now . . .

Oh no! Owwwwwwwww!!!!!

Oh no! Owwwwwwwww!!!!!

<silence>

( silence )

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center.