Ask Question, Ask an Expert

+61-413 786 465

Ask Physics Expert


Please read the given news and prepare 2 (two pages) about:

1) How we put satellites in orbit and

2) Why satellites should eventually fall back to earth.

CAPE CANAVERAL, Florida (AP) — The 6-ton NASA satellite on a collision course with Earth clung to space Friday, apparently flipping position in its ever-lower orbit and stalling its death plunge.

The old research spacecraft was targeted to crash via the atmosphere sometime Friday night or early Saturday, putting Canada and Africa in the potential crosshairs, though most of the satellite should burn up during re-entry. The United States was not entirely out of the woods; the possible strike zone skirted Washington State.

‘It just doesn't want to come down,’ said Jonathan McDowell of the Harvard-Smithsonian Center for the Astrophysics.

McDowell state the satellite's delayed demise describes how unreliable predictions can be. That said, ‘The best guess is that it will still splash in the ocean, just because there is more ocean out there.’

Until Friday, increased solar activity was causing the atmosphere to expand and the 35-foot, bus-size satellite to free fall more rapidly. However late Friday morning, NASA said the sun was no longer the main factor in the rate of descent and that the satellite's position, shape or both had modified by the time it slipped down to a 100-mile orbit.

‘In the last 24 hrs, something has happened to the spacecraft,’ said NASA orbital debris scientist Mark Matney.

On Friday night, NASA said it predicted the satellite to come crashing down between 11:45 p.m. and 12:45 a.m. EDT Saturday. This was going to be passing over the Atlantic, Pacific and Indian oceans at that time, and also Canada and Africa.

‘The risk to public safety is very remote,’ NASA said in a statement.

Any surviving wreckage is expected to be limited to a 500-mile swath.

The Upper Atmosphere Research Satellite, or UARS, will be the biggest NASA spacecraft to crash back to Earth, uncontrolled, as the post-Apollo 75-ton Skylab space station and the more than 10-ton Pegasus 2 satellite, both in 1979.

Russia's 135-ton Mir space station slammed via the atmosphere in 2001; however it was a controlled dive into the Pacific.

Some 26 pieces of the UARS satellite - representing 1,200 pounds of heavy metal - are expected to rain down somewhere. The biggest surviving chunk should be no more than 300 pounds (that is, 136 kilograms).

Earthlings can take comfort in the fact that no one has ever been hurt by falling space junk - to anyone's knowledge - and there has been no serious property damage. NASA put the chances that somebody somewhere on Earth would get hurt at 1-in-3,200. But any one person's odds of being struck were estimated at 1-in-22 trillion; given there are 7 billion people on the planet.

‘Keep in mind that we have bits of debris re-entering the atmosphere every single day,’ Matney said in short remarks broadcast on NASA TV.

In any case, finders definitely are not keepers.

Any surviving wreckage belongs to the NASA, and it is against the law to keep or sell even the smallest piece. There are no toxic chemicals on board, however sharp edges could be dangerous, so the space agency is warning the public to keep hands off and call police.

The $740 million UARS was launched in the year 1991 from space shuttle Discovery to study the atmosphere and the ozone layer. At time, the rules were not as firm for safe satellite disposal; now a spacecraft should be built to burn up upon re-entry or have a motor to propel it into a much higher, long-term orbit.

NASA shut UARS down in 2005 after lowering its orbit to hurry its end. The potential satellite-retrieval mission was ruled out following the 2003 shuttle Columbia disaster, and NASA didn’t want the satellite hanging around orbit posing a debris hazard.

Space junk is a growing problem in the low-Earth orbit. More than 20,000 pieces of debris, at least 4 inches in diameter, are being tracked on a daily basis. Such objects pose a serious threat to the International Space Station.

Physics, Academics

  • Category:- Physics
  • Reference No.:- M9394

Have any Question? 

Related Questions in Physics

Question in an old-fashioned amusement park ride passengers

Question: In an old-fashioned amusement park ride, passengers stand inside a3.0-m-tall, 5.0-m-diameter hollow steel cylinder with their backsagainst the wall. The cylinder begins to rotate about a verticalaxis. Then the ...

A hunter wishes to cross a river that is 1 km wide and that

A hunter wishes to cross a river that is 1 km wide and that flows with a speed of 3 km/h. The hunter uses a small powerboat that moves at a maximum speed of 11 km/h with respect to the water. What is the time necessary f ...

Question storm clouds build up large negative charges as

Question: Storm clouds build up large negative charges, as described in the chapter. The charges dwell in charge centers, regions of concentrated charge. Suppose a cloud has -25 C in a 1.0-km-diameter spherical charge ce ...

Question a package of mass m is released from rest at a

Question: A package of mass m is released from rest at a warehouse loading dock and slides down a 3.0 m-high frictionless chute to a waiting truck. Unfortunately, the truck driver went on a break without having removed t ...

Question situation two electrons each with mass m and

Question: Situation: two electrons, each with mass m and charge q, are released from positions very far from each other. With respect to a certain reference frame, electron A has initial nonzero speed v toward electron B ...

Describe the effect on speed frequency and wavelength of a

Describe the effect on speed, frequency, and wavelength of a sound traveling from warm to cold air. (hint:cold air is more dense than warm air).

Suppose that your users manual lists your cars weight at

Suppose that your user's manual lists your car's weight at 2800 pounds, and you calculate a weight of 2900 pounds based on measurements of the car's tire areas and pressure. What is the percent error between your experim ...

Question a projectile is launched from ground level to the

Question: A projectile is launched from ground level to the top of a cliff which is 195 m away and 135 m high. If the projectile lands on top of the cliff 4.7 s after it is fired, find the initial velocity of the project ...

Question a standard biological microscope is required to

Question: A standard biological microscope is required to have a magnification of 200Ã-. When paired with a 10Ã- eyepiece, what power objective is needed to get this magnification? Part A: Assume that the length of the t ...

Question a rock thrown with speed 120ms and launch angle

Question: A rock thrown with speed 12.0m/s and launch angle 30.0 degrees (above the horizontal) travels a horizontal distance of d = 15.5m before hitting the ground. From what height was the rock thrown? Use the value g ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Why might a bank avoid the use of interest rate swaps even

Why might a bank avoid the use of interest rate swaps, even when the institution is exposed to significant interest rate

Describe the difference between zero coupon bonds and

Describe the difference between zero coupon bonds and coupon bonds. Under what conditions will a coupon bond sell at a p

Compute the present value of an annuity of 880 per year

Compute the present value of an annuity of $ 880 per year for 16 years, given a discount rate of 6 percent per annum. As

Compute the present value of an 1150 payment made in ten

Compute the present value of an $1,150 payment made in ten years when the discount rate is 12 percent. (Do not round int

Compute the present value of an annuity of 699 per year

Compute the present value of an annuity of $ 699 per year for 19 years, given a discount rate of 6 percent per annum. As