14 posts tagged stars
The Horsehead Nebula, a part of the optical nebula IC434 and also known as Barnard 33, was first recorded in 1888 on a photographic plate taken at the Harvard College Observatory. Its coincidental appearance as the profile of a horse’s head and neck has led to its becoming one of the most familiar astronomical objects. It is, in fact, an extremely dense cloud projecting in front of the ionized gas that provides the pink glow so nicely revealed in this GIF.
Explanation: The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51, also known as NGC 5194, is one of the brightest and most picturesque galaxies on the sky. The aboveimage is a digital combination of a ground-based image from the 0.9-meter telescope at Kitt Peak National Observatory and a space-based image from the Hubble Space Telescope highlighting sharp features normally too red to be seen. Anyone with a good pair of binoculars, however, can see this Whirlpool toward the constellation of the Hunting Dogs (Canes Venatici. M51 is a spiral galaxy of type Sc and is the dominant member of a whole group of galaxies. Astronomers speculate that M51’s spiral structure is primarily due to its gravitational interaction with a smaller galaxy just off the top of the image.
As a double-winner of the Nobel Prize, Marie Curie brought global prestige to the Nobel institution in the early part of the Twentieth Century. But few names of Women scientists have been noticed, leave alone, celebrated in the annals of Nobel Prize history ever since. For instance, how many have heard of Dorothy Hodgkin who won the Chemistry Nobel in 1964 for determining the structures of important biochemical substances using X-ray techniques, and was a key figure in the famous Pugwash Conferences on Science and World Affairs? And, how many have cared to know who Maria Goeppert-Mayer was? (She was a co-laureate of the Physics Nobel in 1963 tor findings related to nuclear shell structure, and remains the only woman after Marie curie, to have won the Nobel Prize in this category.)
Similar fundamental, anxious questions could be raised about Gerty Cori, the first Nobel Prize winning woman of America and the first female medical scientist to be inducted into the Nobel hall of fame (for identifying the course of catalytic conversion of glycogen), as well as Rita Levi-Montalcini, the Italian neurologist who co-win the Nobel Prize for Medicine in 1986 (for discovery of the Nerve Growth Factor) and is the oldest living, longest-lived Nobel laureate today. (She completed 102 Years in April 2011).
On the 40th anniversary of the famous ‘Blue Marble’ photograph taken of Earth from space, Planetary Collective presents a short film documenting astronauts’ life-changing stories of seeing the Earth from the outside – a perspective-altering experience often described as the Overview Effect.
Credit: Karl Glazebrook & Ivan Baldry (JHU)
Explanation: What color is the universe? More precisely, if the entire sky were smeared out, what color would the final mix be? This whimsical question came up when trying to determine what stars are commonplace in nearby galaxies. The answer, depicted above, is a conditionally perceived shade of beige. To determine this, astronomers computationally averaged the light emitted by one of the largest sample of galaxies yet analyzed: the 200,000 galaxies of the 2dF survey. The resulting cosmic spectrum has some emission in all parts of the electromagnetic spectrum, but a single perceived composite color.
Distant rocky planet ‘could be future human home’
While Gliese 581d shows potential, it would take around 300,000 years to get there with current space traveling technology.
A survey of the galactic region around our solar system by the European Southern Observatory (ESO) has turned up a surprising lack of dark matter, making its alleged existence even more of a mystery.
Dark matter is an invisible substance that is suspected to exist in large quantity around galaxies, lending mass but emitting no radiation. The only evidence for it comes from its gravitational effect on the material around it… up to now, dark matter itself has not been directly detected. Regardless, it has been estimated to make up 80% of all the mass in the Universe.
A team of astronomers at ESO’s La Silla Observatory in Chile has mapped the region around over 400 stars near the Sun, some of which were over 13,000 light-years distant. What they found was a quantity of material that coincided with what was observable: stars, gas, and dust… but no dark matter.
“The amount of mass that we derive matches very well with what we see — stars, dust and gas — in the region around the Sun,” said team leader Christian Moni Bidin of the Universidad de Concepción in Chile. “But this leaves no room for the extra material — dark matter — that we were expecting. Our calculations show that it should have shown up very clearly in our measurements. But it was just not there!”
Based on the team’s results, the dark matter halos thought to envelop galaxies would have to have “unusual” shapes — making their actual existence highly improbable.
Still, something is causing matter and radiation in the Universe to behave in a way that belies its visible mass. If it’s not dark matter, then what is it?
“Despite the new results, the Milky Way certainly rotates much faster than the visible matter alone can account for,” Bidin said. “So, if dark matter is not present where we expected it, a new solution for the missing mass problem must be found.
“Our results contradict the currently accepted models. The mystery of dark matter has just became even more mysterious.”
An explorer adventures into an unknown world, yet it seems that he has been there before…
music by Alison Melville and Ben Grossman, and foley by Leon Lo. Sound design / mix by Malcolm Sutherland.
The animation is all hand-drawn; a mix of drawing / pastels on paper and digital animation.