What was Alvar Nunez Cabeza de Vaca known for?
Cabeza de Vaca, Álvar Núñez (1490–1557) Spanish explorer. In 1528, he was shipwrecked off the Texas coast. He and three fellow survivors became the first Europeans to explore the American Southwest, eventually settling in Mexico (1536).
Who were pioneers in exploration?
Here are 15 of the most celebrated – and notorious – explorers during the Age of Exploration, before and after.
- Marco Polo (1254-1324)
- Zheng He (c.
- Henry the Navigator (1394-1460)
- Christopher Columbus (1451-1506)
- Vasco da Gama (c.
- John Cabot (c.
- Pedro Álvares Cabral (c.
- Amerigo Vespucci (1454-1512)
Why is Sirius called the Dog Star?
Today, Sirius is nicknamed the “Dog Star” because it is part of the constellation Canis Major, Latin for “the greater dog.” The expression “dog days” refers to the period from July 3 through Aug. 11, when Sirius rises in conjunction with the sun.
What star is brighter than the sun but not hotter?
Betelgeuse is, however, much bigger and brighter. It is about 500 times bigger than our sun. If you put Betelgeuse into our solar system, it would swallow up Mercury, Venus, Earth, and Mars!!! Also it is about 10,000 times brighter than our sun (because a larger star is brighter).
What star has the highest luminosity?
List of stars more luminous than any closer star
| Name | Constellation | Bolometric luminosity (Solar lum.) |
|---|---|---|
| Sun | 1 | |
| Alpha Centauri A | Centaurus | 1.519 |
| Sirius | Canis Major | 25.4 |
| Vega | Lyra | 40.12 |
Which star has the greatest brightness?
For example, the brightest star in the sky, Sirius, sends us about 10 times as much light as the average first-magnitude star. On the modern magnitude scale, Sirius, the star with the brightest apparent magnitude, has been assigned a magnitude of −1.5. Other objects in the sky can appear even brighter.
How old is WR 102?
WR 102ka
| Observation data Epoch J2000. Equinox J2000. | |
|---|---|
| Radius | 92 R ☉ |
| Luminosity | 3,200,000 L ☉ |
| Temperature | 25,100 K |
| Age | <3 Myr |
Do stars have mass?
Massive stars have a minimum mass of 5–10 M ☉. The combination of the radius and the mass of a star determines the surface gravity. Giant stars have a much lower surface gravity than main sequence stars, while the opposite is the case for degenerate, compact stars such as white dwarfs.
Where are the most massive stars in the Milky Way?
The most massive star inside it is, NGC 3603-B, which is a Wolf-Rayet star located at the centre of the HD 97950 cluster which is contained within the large, overall star-forming region. Within our own Milky Way, massive star-forming regions, like NGC 3603, house many stars over 100 times our Sun’s mass.
Is R136a1 a supergiant?
R136a1’s dimensions are far smaller than the largest stars: red supergiants are several hundred to over a thousand R ☉, tens of times larger than R136a1. Despite the large mass and modest dimensions, R136a1 has an average density less than 1% of the Sun’s.
What is the fastest motion of the stars?
Bai et al. Astronomers have spotted the fastest star ever, moving at 8 per cent of the speed of light. The star, called S4714, orbits close to the supermassive black hole at the centre of the Milky Way and could be the best place in the galaxy to test Albert Einstein’s theory of general relativity.
What is the velocity of stars?
In the Milky Way, stars usually have velocities on the order of 100 km/s, whereas hypervelocity stars typically have velocities on the order of 1000 km/s.
How fast do stars move in the Milky Way?
around 10 kilometers per second
Which star is nearest the Earth after the sun?
Alpha Centauri A
Which is the nearest planet to the sun?
Mercury
What is the nearest planet to Earth?
How many planet do we have?
eight planets
Which planet is known as Red Planet?
Mars
Why Mars is red?
Well, a lot of rocks on Mars are full of iron, and when they’re exposed to the great outdoors, they ‘oxidize’ and turn reddish – the same way an old bike left out in the yard gets all rusty. When rusty dust from those rocks gets kicked up in the atmosphere, it makes the martian sky look pink.
Is it hot on Mars?
Temperatures on Mars average about -81 degrees F. However, temperature’s range from around -220 degrees F. in the wintertime at the poles, to +70 degrees F. over the lower latitudes in the summer.