UNI - [ Comet Whacked Neptune 200 Years Ago ]

Comet Whacked Neptune 200 Years Ago | Article Source

Comet Whacked Neptune 200 Years Ago | Universe Today Comet Whacked Neptune 200 Years Ago | Universe Today

Home Carnival of Space Contact Us Guide to Space Privacy Policy Forum July 21st, 2010Comet Whacked Neptune 200 Years Ago

Written by Nancy Atkinson

Neptune. Credit: NASA

Researchers studying Neptune's atmosphere found evidence that a comet may have hit the planet about two centuries ago. Was this a "cold-case" file re-opened, or did they discover a way to travel back in time to witness a long-ago event? To make the discovery, a team from the Max Planck Institute for Solar System Research actually used the Herschel Space Telescope's PACS (Photodetector Array Camera and Spectrometer) instrument, along with what was learned from observations from when the Shoemaker-Levy 9 hit Jupiter sixteen years ago.

The 1994 impact on Jupiter was watched and documented by Voyager 2, Galileo and Ulysses, and today this data helps scientists detect cometary impacts that happened many, many years ago. In fact, just in February of this year, scientists from Max Planck discovered strong evidence for a comet impact on Saturn about 230 years ago. These "dirty snowballs" leave traces of water, carbon dioxide, carbon monoxide, hydrocyanic acid, and carbon sulfide in the atmosphere of the gas giant planets. These molecules can be detected in the radiation the planet radiates into space.

So, the team turned their attention to Neptune, and used the PACS to analyze the long-wave infrared radiation of Neptune.

The atmosphere of Neptune mainly consists of hydrogen and helium with traces of water, carbon dioxide and carbon monoxide. However, the scientists detected an unusual distribution of carbon monoxide in the stratosphere, the upper layer of the atmosphere, and found a higher concentration than in the layer beneath, the troposphere. "The higher concentration of carbon monoxide in the stratosphere can only be explained by an external origin," said MPS-scientist Paul Hartogh, principal investigator of the Herschel science program. "Normally, the concentrations of carbon monoxide in troposphere and stratosphere should be the same or decrease with increasing height," he said.

Another theory suggested that a constant flux of tiny dust particles from space introduces carbon monoxide into Neptune’s atmosphere. However, the newest observations from PACS does not lend credence to that idea, and the team concluded the only explanation for these results is a cometary impact. Such a collision forces the comet to fall apart while the carbon monoxide trapped in the comet’s ice is released and over the years distributed throughout the stratosphere.

"From the distribution of carbon monoxide we can therefore derive the approximate time, when the impact took place," said Thibault Cavalié from MPS, which showed the impact was about 200 years ago.
PACS was developed at the Max Planck Institute for Extraterrestrial Physics, and it analyzes the long-wave infrared radiation, also known as heat radiation, that the cold bodies in space such as Neptune emit.

Source: Max Planck

Filed under: Neptune, Observatories

Tags: Herschel Telescope, Neptune

Comment policy: Be nice and brief. Don't advertise your stuff, or promote your personal theories. We'll delete any comments that break these policies. Click here for more details.

10 Responses to “Comet Whacked Neptune 200 Years Ago”Torbjorn Larsson OM Says:
July 21st, 2010 at 11:14 am

Something whacked this way comes.

Hooray for thermodynamical imbalances!

Navneeth Says:
July 21st, 2010 at 12:21 pm

Scientists from Max Planck? Are they called Plancklets?

Torbjorn Larsson OM Says:
July 21st, 2010 at 2:59 pm

Navneeth, that is cute!

Wonder if Plancklets believe in Heisenberg or Schroedinger, and if so if they keep a Planck Mass?

Aqua Says:
July 21st, 2010 at 4:53 pm

Hmm… a comet hits Saturn +/-230 years ago, then another hits Neptune +/-200 years ago. Given the approximate dates, I wonder if this is more than simply coincidence? The planetary alignment that allowed the Voyager missions to reach the outer planets occurs every 176 years and happened in the late 1970's. Those alignments may also disturb the orbits of cometary objects in the Kuiper belt and/or the Oort Cloud. Given long transit times of cometary bodies from those two sources, I wonder if this could this be part of a suspect 'coincidence'?

Uncle Fred Says:
July 21st, 2010 at 6:16 pm

If Neptune is mostly Gaseous, how exactly does a Comet "Wack it? ..just curious…

Lawrence B. Crowell Says:
July 21st, 2010 at 7:51 pm

It impacts it just as Shoemaker-Levy 9 hit Jupiter in 1994. The comet generates an enormous shock wave as it enters increasingly dense gas.

You don't hear a lot about Neptune. At UT Mars has 833 pages and Neptune has 16. Though Neptune muscles out Uranus with only 5. It's cold an lonely out there, and astronomically these frigid small gas giants get the Rodney Dangerfield award of "no respect."

vagueofgodalming Says:
July 22nd, 2010 at 3:39 am

I wonder if this is more than simply coincidence?

I had the same thought, but made the opposite hypothesis: that there's a hitherto un-modelled atmospheric process that mimics a two hundred year cometary signature in the upper atmosphere.

Easy enough to test: (1): look at Uranus; (2) track Neptune and Saturn over time: if you get slow decay with new peaks, it's comets, if not, it's something else.

It's my version of Occam's Razor: given two explanations, the more boring one is true. Applies only to press releases, not actua;l scientific papers.

Uncle Fred Says:
July 22nd, 2010 at 5:12 am

@LC:
lol, I understand thanks.

It's too bad we don't hear more about these two worlds. I think modern Cassini type probes for Uranus and Neptune and their various icy moons should be one of NASA's top priorities going forward.

John Mendenhall Says:
July 22nd, 2010 at 8:17 am

Bjorn, they believe in Heisenberg and Schroedinger simultaneously, but they avoid observing Planck mass because one of them would become real and the other one would disappear.

Tauridborn Says:
July 22nd, 2010 at 10:49 am

-Aqua

No. The planetary alignment could not have affected the oort cloud. If the as-yet-undetected oort cloud was affected by planetary alignments, we would have gotten a shower of comets in the seventies. Also, the Saturn impact would be before the planetary alignment (assuming the method is accurate).

Leave a Reply

You must be logged in to post a comment.

« First Quasar Gravitational Lens Discovered (w/video) New Technique Could Track Down Dark Energy » Categories2012 (14)Archive (93)Asteroids (215)Astrobiology (100)Astronomy (5621)Astronomy For Kids (28)Astrophotos (265)Astrosphere (102)Black Holes (155)Blog (60)Book Reviews (209)Carnival of Space (107)Cassini (6)Chandra (59)China (13)Citizen Science (18)Climate (5)Comets (65)Commercial Space (15)Constellation (71)Cosmology (68)Dark Energy (26)Dark Matter (48)Earth (94)Earth Observation (292)Eclipses (23)Enceladus (10)Environment (58)esa (21)Europa (8)Evolution (5)Extrasolar Planets (250)Extreme Life (27)Fraser's News (2)galaxies (115)Gamma Ray Bursts (28)Giveaways (3)Gravitational Lensing (29)Hubble (285)IYA 2009 (52)IYA Live Telescope Library (39)James Webb (5)Jupiter (86)Mars (833)Mercury (32)Meteor Showers (20)Meteorites (52)Military (17)milky way (21)Missions (515)Moon (264)NASA (374)Natural Disasters (15)Neptune (16)Observatories (146)Observing (182)Orion (9)Physics (117)Planet News (11)Planetary Formation (17)Pluto (43)Podcasts (235)Questions (8)Radio Astronomy (4)Satellites (244)Saturn (475)Science (89)SETI (26)Skywatching (29)Solar Astronomy (89)Solar System (41)Space Exploration (220)Space Flight (329)Space Shuttle (414)Space Station (306)Space Tourism (50)Spitzer (38)Sponsors (2)sun (6)supernova (2)Technology (34)Telescope Reviews (28)Titan (38)Uncategorized (21)Universe Today News (5)Uranus (5)Venus (41)What's Up (91)Where In the Universe? (117)Email newsletter

Daily Edition
Weekly Edition

Close Prev Next