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Can we ever see nebulas in the night?
REINA,
AGE 10, HONG KONG Answer: Yes, we can
definitely see nebulae at night. They are huge clouds of gas and dust where stars
form. Take a look for the constellation of Orion and there is a really good nebulae
just below the three stars that make up his belt. Look at the area in binoculars
and you will be able to see it. Without binoculars
it will look like a fuzzy patch but you must be away from the lights of cities
and towns to see it well. How do reflective telescopes
like Hubble work?
JESSICA, AGE 14, WELLINGBOROUGH Answer:
Reflecting telescopes work because they have very special mirror's
inside them. The main mirror has a slight curve on it and sits at the bottom of
the telescope tube. Light from a star falls down the telescope tube, hits the
main mirror and bounces back up the tube. It then lands on a much smaller secondary
mirror which sends the light out the side of the tube where the astronomer looks
to see the image. Can you see any other planets
with the Hubble telesope in another galaxy?
RICHARD,
AGE 17, MANSFIELD Answer: It's
possible for the Hubble Space Telescope to just about pick out planets outside
our own Solar System, but not possible for it to see planets in other galaxies.
They are too far away and the planets would be very hard to detect. We can make
out individual stars in nearby galaxies, but it may be a very long time, if ever
that we can see individual planets there too. Does
every star become a shooting star?
REINA, AGE 9, HONG KONG Answer:
It seems silly but stars are nothing to do with
shooting stars! A star is a big ball of gas many millions and millions of miles
away but a shooting star is a piece of rock or dust that falls through the sky.
What does sunlight tell astronomers? And how
large are stars?
ANONYMOUS Answer:
If we take a look at the light from the Sun, or any star we can tell what
it is made up of, what temperature it is and can even work out roughly how big
it is. What is a reflection nebula made of?
ANONYMOUS Answer:
There are three main types of nebula, dark, reflection and emission. They are
all made up of the same stuff but just appear different because of their varying
distance with stars. All the nebulae are generally
vast clouds of dust and hydrogen gas, with some smaller amounts of other gasses.
Hello, I'm a fourth year Architecture and
Planning student and intend to undertake a design project related to astronomy.
I have heard that it is possible to see stars during the daytime through a lone
tube but any evidence I read informs me that this is a myth. Can
you confirm that this is the case? If it is not possible, are there other ways
of seeing the stars during the day through a device or structure? Thank you.
RICHARD, AGE 21, BRISTOL Answer:
I'm afraid I can confirm it is a myth that you
can see stars through a long tube. There is a big BUT to this statement.
It is quite possible to see stars and planets during the daytime through a normal
astronomical telescope or binoculars if the object is bright enough. The
only reason we cannot generally see them in the daytime is because the sunlight
lights up the sky. It simply makes it harder to see them but they can still be
seen. I have often looked at Saturn, Jupiter and a number of stars in daylight!
What do radio telescopes tell the astronomer
about objects in space?
SARA, AGE 13 Answer:
Radio telescopes tell us many things about objects
in space. The great benefit of radio telescopes is that the radio signals they
pick up will travel through clouds in our sky but also through clouds of dust
in space. We can use a radio telescope to see things
we cannot see with a normal telescope such as the centre of our galaxy! | 
An astronomical telescope
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What
are special parts of the astronomical telescope?
KELLY, AGE
14, CHARLTON Answer: There
are two common types of astronomical telescopes. A refracting telescope, like
the ones you see sailors using. They have a lens at one end and an eyepiece (which
is just a collection of other lenses) at the other end. This
is all held together in a tube. So the light passes through the main lens, down
the tube, through the eyepiece and into your eye. The
other type of telescope is the reflecting type. It uses mirrors instead of a lens.
At the bottom of the tube is a large round mirror, at the top of the tube is a
smaller flat mirror set at an angle and then an eyepiece on the side.
The light from a star falls down the tube, hits the big round mirror, bounces
back up the tube and hits the second smaller flat mirror which sends the light
out the side of the tube into the eyepiece and into your eye.
The reflecting telescopes are cheaper and much more popular for astronomy.
Which constellation is Polaris in?
SARAH,
COLLINGWOOD Answer: The star Polaris,
also known as the Pole Star, is in the constellation of Ursa Minor. How
many stars are there in our galaxy?
LAUREN, AGE 10, VICTORIA Answer:
Our Galaxy, called the Milky Way has about 100
thousand million stars in it! This may sound like loads but there are other galaxies
that are much larger. How exactly does a
star form into a black hole?
MANILA GUPTA, AGE 18, DELHI,
INDIA 
Black hole |
Answer:
What a cracking question. I will try and answer
this as briefly as possible. Stars are created (generally speaking) out of clouds
of hydrogen gas and dust. Inside the star, the hydrogen
atoms smash together to form helium. It's this process that produces an outward
force on the star trying to push it apart. But gravity
is trying to pull the star back together again. For
many millions of years, the balance of the two forces is equal and the star is
stable. Eventually the star runs out of hydrogen in the core and starts to fuse
the helium atoms into another chemical. This continues for the heavier stars until
the core is made of iron. It is not possible to
fuse iron atoms together to produce more energy so suddenly there is no outward
pressure and the force of gravity wins. The core of the star catastrophically
collapses crushing it down into a range of different objects! For
the most massive stars in the universe this creates a black hole. A remnant of
the core of a super massive black hole with no dimension, yet of infinite mass!
How does the distance from the sun affect the
length of time it takes the planet to orbit the Sun?
RYAN
MCGUINNESS, AGE 14, BIRMINGHAM Answer:
All of the planets orbit the Sun in an elliptical orbit.
That means that their distance from the Sun varies as they go around it. When
the planet gets closer to the Sun it travels quicker and when it gets further
away it slows down. For us here on Earth, the Earth is closer to the Sun in winter
and so is travelling faster than in the summer when it is further away. The
difference between the two is about 1 km per second. More
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