Table of Contents
Do stars have arms?
Most sea stars have five arms, although some can grow as many as 50 arms. Most sea stars have five arms, although some can grow as many as 50 arms.
Does the Milky Way have 4 arms?
The exact number of arms, and their shapes, is difficult to determine from our location within the Milky Way. Astronomers think the Milky Way has 4 main spiral arms and a number of fragments of arms, called spurs. Astronomers have many ways to observe our galaxy.
Why do stars form in arms?
The stars and gas and dust clouds in the disk congregate in a spiral pattern. Star formation occurs in the spiral arms because the gas clouds are compressed in the arms to form stars. The very luminous, short-lived O and B-stars and H II regions around them enhance the spiral outline.
What galaxy has no arms?
When a spiral galaxy has no arms, S0, it is termed lenticular. These galaxies are so similar to E7 that identifying them can be tricky. Lenticular galaxies also occur with barred spiral and are classified as SB0.
Do all starfish have 5 arms?
All starfish resemble stars, and though the most common have only five arms, some of these animals can grow up to 40 arms. The amazing sea creatures—part of a group of animals known as echinoderms—travel using their tube feet. They can regenerate lost limbs and swallow large prey using their unusual stomachs.
Can starfish sting you?
Starfish do not attack humans, but can inflict painful stings with the release of venom, when they are accidently stepped upon or handled (picked up). It is mainly the deep sea divers who are at risk. Immediate medical attention has to be sought in case of severe stings.
Is there a black hole in Milky Way?
For several years the scientific community has agreed that there is a mass at the center of the Milky Way galaxy and that the mass is a supermassive black hole—it has been named Sagittarius A*.
Why Milky Way is spiral?
The Milky Way is a huge collection of stars, dust and gas. It’s called a spiral galaxy because if you could view it from the top or bottom, it would look like a spinning pinwheel. The Sun is located on one of the spiral arms, about 25,000 light-years away from the center of the galaxy.
Do all galaxies rotate?
Astronomers have discovered that all galaxies rotate once every billion years, no matter how big they are. “But regardless of whether a galaxy is very big or very small, if you could sit on the extreme edge of its disk as it spins, it would take you about a billion years to go all the way round.”
What are the 3 main galaxies?
What Kinds of Galaxies Are There? Astronomers classify galaxies into three major categories: elliptical, spiral and irregular.
How many arms and legs does a starfish have?
With 10, 40 or the classic five limbs, starfish – more accurately, ‘seastars’ – prowl the craggy intertidal zone, while brittle and basket stars prefer the deepest, muddy parts of the ocean. The underside of each limb is studded with hydraulically operated tube ‘feet’, tipped with suction cups for feeding and locomotion.
How many arms does a sea star have?
While the characteristic sea star figure that we tend to visualize in our minds has a total of five arms, these organisms refuse to be limited by our assumptions when it comes to their number of limbs. With more than 2,000 species of sea stars in our ocean today, there are individuals that present with 10, 20 or even 50 arms.
Why are stars shaped the way they are?
Stars are shaped like stars, says Henry Reich in the Minute Physics video above, because of imperfections in the back of our eyeballs. Most intriguingly, says Reich, this biological explanation means that every one of us sees stars slightly differently.
Why do sea stars appear as black dots?
Usually appearing as a dot that is either black or reddish in coloration, these spots are photosensitive, enabling sea stars to recognize shapes as they navigate over the seafloor and around both peers and prey. Sea stars are iconic creatures and are far more unique than they appear at first sight.