Friday, August 17, 2018

Astronomers Discover Rogue World with Wild Auroras

Astronomers using the National Science Foundation's Karl G. Jansky Very Large Array (VLA) have discovered a free-floating world with a powerful magnetic field four million times stronger than the one around Earth. This rogue planet is a world drifting in space between stars.
Known as SIMP J01365663+0933473 by astronomers, this newly-discovered world is only 20 light-years from Earth. This is the first ever planetary-mass object to be detected by radio telescopes and the first time scientists have measured the magnetic field of one of these rogue worlds.
It is suspected that the aurora produced on this world are more similar to Jupiter's than Earth's due to a suspected moon.. On Earth, the aurora are a by-product of solar wind particles bombarding the planet's magnetic field. To contrast, Jupiter's auroras are produced primarily by charged particles coming from its volcanically active moon Io.
"This particular object is exciting because studying its magnetic dynamo mechanisms can give us new insights on how the same type of mechanisms can operate in extrasolar planets," said Melodie Kao at Arizona State University, lead scientist of this study. "We think these mechanisms can work not only in brown dwarfs, but also in both gas giant and terrestrial planets."
It is currently estimated that there might be one Jupiter-mass rogue planet for every four stars in our galaxy. Observations of these free-floating worlds have helped to readjust this estimate over time.

Image Credits: Caltech/Chuck Carter/NRAO/AUI/NSF

Thursday, August 16, 2018

Photo of the Week

Photo of the Week
This week for Photo of the Week, we would like to feature a fantastic photo of the Milky Way. Taken over Norah Head, New South Wales, Australia, this lovely photo features the Norah Head LIghthouse underneath the beautiful Milky Way Galaxy. Like a beacon of light, this lighthouse shines brightly while contrasting with the natural splendour of the stars of our home galaxy.
For more fantastic photos, be sure to check out @scneicdreamsphotography and while at it, take a look at some of their other services such as astro workshops and wedding photography: https://www.instagram.com/scenicdreamsphotography/

Wednesday, August 15, 2018

Hydrogen Wall May Have Been Detected at the Edge of the Solar System

  NASA's New Horizons spacecraft has recently spotted an ultraviolet glow that appears to be emanating from near the edge of the solar system. According to a new study released by scientists working on the mission, this could be the long-sought wall of hydrogen that represents the boundary of our solar system where the sun's influence diminishes greatly.
  As the sun travels through our galaxy, it produces a constant stream of charged particles known as the solar wind. This inflates as a safety bubble around the solar system called the heliosphere. Beyond this bubble, uncharged hydrogen atoms in interstellar space should slow and accumulate when they collide with solar wind particles, creating scattered ultraviolet light.
  Signs of this light scattering were observed 30 years ago by the two Voyager spacecraft. New Horizons is the first spacecraft in a position to reaffirm the Voyagers' observations. For the last 7 years the spacecraft has made seven separate observations that appear to support the decades-old observations.
  “We’re seeing the threshold between being in the solar neighborhood and being in the galaxy,” said team member Leslie Young of the Southwest Research Institute, located in Boulder, Colorado.
  “It’s really exciting if these data are able to distinguish the hydrogen wall,” said physicist David McComas of Princeton University, who was not involved in the new work. 

Read the full study here: https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2018GL078808 

Image Credit: Adler Planetarium/IBEX/NASA 

Tuesday, August 14, 2018

How Much Salt is Too Much?

The risk of cardiovascular disease and stroke has been found to increase in individuals who consume more than 5g or 2.5 teaspoons of sodium a day. In a study of 94,000 individuals from 18 different countries aged 35-70 years old over the course of 8 years, the majority of communities consumed an average sodium intake of 3-5 grams or 1.5-2.5 teaspoons a day.

China was the only country from the study where a majority (80% of communities) consumed an excess of 5g of sodium a day. “Only in the communities with the most sodium intake — those over 5g/day — which is mainly in China, did we find a direct link between sodium intake and major cardiovascular events like heart attack and stroke,” explains lead author Dr. Andrew Mente from the Population Health Research Institute of McMaster University.

These results contradict The World Health Organization which recommends individuals consumed less than 2g of sodium a day and The American Heart Association which recommends an intake of less than 1.5g of sodium a day. Dr. Mente argues, “These recommendations are primarily based on individual-level data from short-term trials of blood pressure without data relating low sodium intake to reduced cardiovascular events from randomised trials or observational studies.” The study led by Dr. Mente instead uses community-level sodium and potassium consumption, cardiovascular disease, and mortality in order to form a conclusion.

Read more about this fascinating discovery at:
http://www.sci-news.com/medicine/salt-consumption-heart-06297.html

Read the study at:
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31376-X/fulltext


Monday, August 13, 2018

NASA's Parker Solar Probe Blasts Off on Mission to the Sun

  On Sunday August 12 at 3:31 a.m. EDT, NASA"s Parker Solar Probe began its journey for a rendezvous with the Sun. Carried by a United Launch Alliance Delta IV Heavy rocket, the probe was launched from Cape Canaveral Air Force Station in Florida.
  “It was a very quiet launch countdown, it went off like clockwork,” said Omar Baez, NASA Launch Director. “Parker Solar Probe has been one of our most challenging missions to date. I’m very proud of the team that worked to make this happen. We at NASA and the Launch Services Program are thrilled to be part of this mission.”
  The Parker Solar Probe's mission is to ultimately 'touch' the sun. Using gravity assists from Venus seven times over nearly seven years, the probe will gradually bring its orbit closer to the Sun. The goal is to get the probe to fly directly through the Sun's atmosphere, breezing by 6.1 million kilometres (3.8 million miles) from the surface.
  Facing brutal heat and radiation, the spacecraft will fly close enough to witness the solar wind speed up from subsonic to supersonic speeds and observe their birth. This will only be possible thanks to the probe's 4.5-inch-thick, carbon-carbon composite heat shield. The front surface of the probe will be able to withstand temperatures of up to 1350 °C  (2500 °F) while the back and insides will be withstand up to 350 °C (650 °F).


Image: Long exposure view of the rocket streaking through a thick cloud layer during the ascent into space via NASA/Bill Ingalls

Sunday, August 12, 2018

This Week in Science History: Launch of the International Cometary Explorer

On August 12, 1978, the International Cometary Explorer (ICE) was launched. The ICE was a part of the Internation Sun-Earth Explorer (ISEE) program which consisted of 3 satellites: ISEE-1 and ISEE-3 (the principal US contribution to the International Magnetospheric Study),  and ISEE-2 (built and managed by ESA). On October 22, 1977,  ISEE-1 and -2 were launched into almost coincident orbits. The orbital period was 57 hours. On August 12, 1978, ISEE-3 was launched and  inserted into a "halo" orbit between the Earth and Sun. Later, ISEE-3 was renamed the International Cometary Explorer (ICE) after the completion of its mission in 1982 when it was used to intercept the comet P/Giacobini-Zinner. On September 11, 1985, the spacecraft flew through the tail of the comet.

Read more at: https://heasarc.gsfc.nasa.gov/docs/heasarc/missions/isee3.html

Photo of the Week

 This week we would like to feature a stunning star trails shot captured by photographer Steve Ryan. Taken during the Perseid Shower five years ago, this photo was compiled specifically to highlight the meteors. Instead of the usual smooth lines visible in a typical star trails photo, this shot combined frames that were taken consecutively of each other with some that were taken minutes apart to create the segmented effect visible in the round circles of the trails.

 For more fantastic photos, be sure to check out Ryan's Flickr account at: https://www.flickr.com/photos/juniorvelo/