Because Congress failed to avert a shutdown, 800,000 federal employees have been told to stay home. What else is affected?

Well, they did it. The US government is officially on a partial shutdown, with Congress having failed to reach an agreement by midnight on Monday.

The shutdown will have far-reaching effects throughout the US. Though some services – mail delivery, Social Security and Medicare benefits – are not affected, others, like national parks and routine safety inspections of food, are curtailed as the majority of federal employees tasked with their operation have been ordered not to report to work on Tuesday.

A look at how a shutdown will affect other services across the federal government:

Federal workers

About 800,000 federal employees are not furloughed and will not be paid. Already hit hard by several unpaid furlough days caused by sequestration this year some workers have begun lobbying to receive back pay in the event of a shutdown. While Congress agreed to retroactively pay them during previous shutdowns, the fractured nature of this Congress makes such a step unlikely.

US military

The military's 1.4 million active-duty personnel will stay on duty, but their paychecks initially faced a threat of delay. Amid the division, the House passed – and Obama signed – a bill to ensure their checks would still be delivered on time. "You and your families deserve better than the dysfunction we're seeing in Congress," Obama said.

About half of the Defense Department's civilian employees are furloughed.

Food programs

The Wic program, which provides low-income pregnant women, new mothers and children up to the age of five with healthy food, is not funded as of Tuesday morning. "No additional federal funds would be available," says the Department of Agriculture, though it suggests that some states – some, not all – may have a state-run fund that can fill in the gaps for women who need help purchasing things like formula. They estimate the state funds would last about a week.

School lunches for low-income students are not affected. Food stamps are not affected.

Public health

The Centers for Disease Control and Prevention are facing a reduced ability to detect and investigate disease outbreaks. The annual influenza program – the one that tracks the flu and helps people get flu shots – has been shut down. The CDC has also stopped offering its usual assistance to state and local authorities, who rely on the agency for help in tracking unusual outbreaks.

The National Institutes of Health will continue to treat patients at its hospital center, but no new clinical trials will begin.

Animals

National Zoo (@NationalZoo) None of our live animal cams will broadcast during the #shutdown. The cams require federal resources, primarily staff, to run and broadcast.

The animals at the National Zoo are being cared for, but the zoo, like all Smithsonian museums, is closed to the public. The live animal cams have been shut down. That's right, Congress' inability to reach a deal means no more panda cam, America.

Science

Nasa will furlough almost all of its employees, though it will continue to keep workers at Mission Control in Houston and elsewhere to support the International Space Station, where two Americans and four others are deployed. The National Weather Service will keep forecasting weather and issuing warnings, and the National Hurricane Center will continue to track storms.

Travel and tourism

National parks and monuments are closed, including the Grand Canyon, Yosemite, the National Mall and the Statue of Liberty. Park rangers spent Tuesday morning erecting barricades to prevent people from accessing these public spaces.

Federal air traffic controllers will remain on the job and airport screeners will keep funneling passengers through security checkpoints, though some airports have warned of delays at security. Federal inspectors will continue enforcing safety rules.

The State Department will continue processing foreign applications for visas and US applications for passports, since fees are collected to finance those services. Embassies and consulates overseas will continue to provide services to American citizens.

Courts

Federal courts will continue operating normally for about 10 business days after the start of a shutdown, roughly until the middle of October. If the shutdown continues, the judiciary would have to begin furloughs of employees whose work is not considered essential. But cases will continue to be heard.

The US supreme court is scheduled to begin its new term on October 7. In previous government shutdowns, it continued to operate as normal.

Mail

Deliveries will continue as usual because the US Postal Service receives no tax dollars for day-to-day operations. It relies on income from stamps and other postal fees to keep running.

District of Columbia

The city, which does not have autonomy over its own budget, briefly flirted with the idea of using the potential shutdown to make a stand when mayor Vince Gray moved to designate all city employees "essential," thereby avoiding the cuts in services like libraries that were expected. Some District politicians were willing to go so far as to get arrested over the show of defiance, but on Friday the city's lawyers approved using a $144m contingency fund to make up the difference when the federal government funds dry up.

Weddings, however, are on hold in the city.

Homeland security

The majority of the Department of Homeland Security's employees will stay on the job, including uniformed agents and officers at the country's borders and ports of entry, members of the Coast Guard, Transportation Security Administration officers, Secret Service personnel and other law enforcement agents and officers. US Citizenship and Immigration Services employees will continue to process green card applications.

Veterans services

Most services offered through the Department of Veterans Affairs will continue because lawmakers approve money one year in advance for the VA's health programs. Veterans will still be able to visit hospitals for inpatient care, get mental health counseling at vet centers or get prescriptions filled at VA health clinics. Operators will still staff the crisis hotline and claims workers will still process payments to cover disability and pension benefits.

But those veterans appealing the denial of disability benefits to the Board of Veterans Appeals will have to wait longer for a decision because the board will not issue any decisions during a shutdown.