The average density of matter in a white dwarf is 109 kg/m3. Many white dwarfs are approximately the size of the Earth, but their mass is typically about 0.4–1.4 solar masses.

Reliance on the surface temperature stars have got different colours?

Hotter stars tends to look a bluish colour, cooler stars are dark red. The colours in descending order of temperature: blue, white, yellow, orange and then red. Our sun has a surface temperature of 5 500oc and appears yellow so it is between those extremes. Temperatures of some well-known stars are presented in the table.

The date of Easter is closely connected with the full Moon?

The Sunday of the Resurrection occurs the first sunday after first full Moon after a spring equinox.
We are calculating another dates connected with the liturgical year, for example:

• Palm Sunday is a moveable feast which falls on the Sunday before Easter
• Great Thursday is the feast or holy day on the Thursday before Easter
• Good Friday is the Friday before Easter
• Holy Saturday is the day before Easter
• Ascension is the fortieth day after Easter
• Pentecost is the fiftieth day after Easter Sunday

The Southern hemisphere has summer when the Northern Hemisphere has winter?

The seasons of the northern hemisphere and southern hemisphere are opposites.

In the whole European Union occurs a daylight saving time(DST)?

In spring the clock jumps forward from 01:00 standard time to 02:00 DST and the day has 23 hours, whereas in autumn the clock jumps backward from 02:00 DST to 01:00 standard time, repeating that hour, and the day has 25 hours.

The longest human's stay in space runs 741 days?

The record belongs to Russian Siergiej Awdiejew born in 1956. This time is a sum of three missions in years: 1992/93, 1995/96 and 1998/99.

The oldest man in the space had got 77 years?

29th October 1998 on the shuttle's deck Discovery flew into space american senator, 77-old John Lenn.

First footprint on the Moon's surface will look a million years from now probably the same as it looked in 1969?

The Moon has no atmosphere and no liquid water, so erosion is very slow. It is mainly caused by the impact of tiny micrometeoroids on the Moon's surface. Erosion on the Earth is the result of flowing water, falling rain, and blowing wind.

Galileo Galilei wrongly believes that there are oceans on the Moon?

The Lunar maria are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich compositions, and hence appear dark to the naked eye. Now we have got e. g. Sea of Serenity (Mare Serenitatis), Sea of Nectar (Mare Nectaris ) and Ocean of Storms ( Oceanus Procellarum).

There are two inferior and five superior planets in our Solar System?

Inferior planet is used in reference to Mercury and Venus, which are closer to the Sun than the Earth is. Whereas superior planet is used in reference to Mars, Jupiter, Saturn, Uranus, Neptune, and all the known dwarf planets, including Ceres and Pluto, which are farther from the Sun than the Earth is.

There are four terrestrial planets and four Jovian planets in our Solar System?

A terrestrial planet is a planet that is primarily composed of silicate rocks. Earth's solar system has four terrestrial planets: Mercury, Venus, Earth and Mars. A gas giant (sometimes also known as a Jovian planet after the planet Jupiter) is a large planet that is composed mostly of some combination of hydrogen, helium, and water existing in various physical states. There are four gas giants in our Solar System; Jupiter, Saturn, Uranus and Neptune.

You can study astronomy at six Polish universities?

• University of Warsaw
• Nicolaus Copernicus University in Torun
• Jagiellonian University in Cracow
• University of Wrocław
• Adam Mickiewicz University in Poznan
• University of Gdansk
• University of Zielona Gora.

A light-year or lightyear is a unit of measurement of length?

It is the distance light travels in vacuum in one year.

It takes about 8 minutes 30 seconds for light to travel from the Sun to the Earth?

For comparison, it takes about 1 minut for light to travel from the Earth to the Moon.
The star Proxima Centauri, the nearest star to the Sun, is at a distance of 4.22 light years.

There are 88 constellations?

The International Astronomical Union (IAU) divides the sky into 88 official constellations with precise boundaries, so that every direction or place in the sky belongs within one constellation.

The largest moon in the entire Solar System is Jupiter's moon – Ganymede?

Discovery of the moon is generally credited to Galileo Galilei who documented its existence in 1610 . He discovered four Jupiter's moons: Io, Europa, Ganymede and Callisto.

The Sun is shining about 5 billion years and will be shining consecutive 5 billion years?

The Sun's current age, determined using computer models of stellar evolution and nucleocosmochronology, is thought to be about 4.57 billion years. The Sun is about halfway through its main-sequence evolution, during which nuclear fusion reactions in its core fuse hydrogen into helium. in 4-5 billion years, it will enter a red giant phase. Following the red giant phase, intense thermal pulsations will cause the Sun to throw off its outer layers, forming a planetary nebula. The only object that will remain after the outer layers are ejected is the extremely hot stellar core, which will slowly cool and fade as a white dwarf.